Scipedia: Documents published in 2017

Pharmacogenomics-guided policy in opioid use disorder (OUD) management: An ethnically-diverse case-based approach

Scipedia content — Fri, 26 May 2017 11:05:45 +0200

Opioid use disorder (OUD) is characterized by a problematic pattern of opioid use leading to clinically-significant impairment or distress. Opioid agonist treatment is an integral component of OUD management, and buprenorphine is often utilized in OUD management due to strong clinical evidence for efficacy. However, interindividual genetic differences in buprenorphine metabolism may result in variable treatment response, leaving some patients undertreated and at increased risk for relapse. Clinical pharmacogenomics studies the effect that inherited genetic variations have on drug response. Our objective is to demonstrate the impact of pharmacogenetic testing on OUD management outcomes. We analyzed a patient who reported discomfort at daily buprenorphine dose of 24 mg, which was a mandated daily maximum by the pharmacy benefits manager. Regular urine screenings were conducted to detect the presence of unauthorized substances, and pharmacogenetic testing was used to determine the appropriate dose of buprenorphine for OUD management. At the 24 mg buprenorphine daily dose, the patient had multiple relapses with unauthorized substances. Pharmacogenetic testing revealed that the patient exhibited a cytochrome P450 3A4 ultrarapid metabolizer phenotype, which necessitated a higher than recommended daily dose of buprenorphine (32 mg) for adequate OUD management. The patient exhibited a reduction in the number of relapses on the pharmacogenetic-based dose recommendation compared to standard dosing. Pharmacogenomic testing as clinical decision support helped to individualize OUD management. Collaboration by key stakeholders is essential to establishing pharmacogenetic testing as standard of care in OUD management.

Predicting early onset of intoxication versus drinking—A population-based prospective study of Norwegian adolescents

Scipedia content — Fri, 26 May 2017 11:05:39 +0200

Recent research suggests that early onset of intoxication (EOI) may be of greater importance for a wide range of subsequent adverse outcomes than early drinking experiences without intoxication. However, research on antecedents of EOI is scarce. The present study identifies predictors of EOI and whether they differ from those of early onset of drinking (EOD). Data was drawn from the prospective Tracking Opportunities and Problems (TOPP) study of Norwegian families (n = 382), which followed up mothers and their children with six data collections from childhood (age 1.5) to adolescence (age 14.5). Self-reports from the adolescents (parenting practices, adolescents conduct problems and friends' deviant behaviour) and their mothers (adolescent temperament, socio-economic factors and household alcohol problems) were used to identify predictors of EOI and EOD. A variety of temperamental, socio-economic, and family factors predicted EOI, whereas EOD was predicted of substantially fewer variables. Particularly, when controlling for relevant covariates, low levels of shyness, own conduct problems and having friends with deviant behaviour prospectively predicted EOI, but not EOD. Future research and prevention efforts should take into consideration that EOI and EOD without getting drunk appear to be predicted by different risk factors in childhood and adolescence.

Development and validation of a short Italian UPPS-P Impulsive Behavior Scale

Scipedia content — Fri, 26 May 2017 11:05:34 +0200

Impulsivity is a multidimensional construct that plays a prominent role in the development, maintenance, and relapse of addictive disorders. The UPPS-P model of impulsivity, which distinguishes between five impulsivity components (positive urgency, negative urgency, lack of perseverance, lack of premeditation, sensation seeking), has been increasingly investigated during the last decade in relation to addictive and risky behaviors. Unfortunately, it currently lacks a validated scale that allows Italian researchers and clinicians to measure impulsivity based on the UPPS-P model. The current study fills this gap by testing the psychometric properties of a short 20-item Italian scale used to assess the five dimensions of the UPPS-P model in 188 volunteer participants from the community. Confirmatory factor analysis supported a model of five distinct, but interrelated, impulsivity components. The results indicated good internal consistency (Cronbachs α ranges from .73 to .84). Construct validity was evidenced by specific relations with measures of addictive behaviors and depressive symptoms. On the whole, this study demonstrated that the Italian short UPPS-P has good psychometric properties.

Drinking game participation, gender performance and normalization of intoxication among Nigerian university students

Scipedia content — Fri, 26 May 2017 11:05:29 +0200

Most research on drinking games (DGs) and the associated risks focuses on Western countries. In the Nigerian context, DGs activity has not attracted scholarly attention but growing media reports indicate that Nigerian youths play DGs, and that a number of gamers have died during or immediately after game-playing. Drawing on gender performance scripts, we explored the performance of gender through DGs practices and the factors that motivate DGs participation. Thirty-one in-depth interviews were conducted with male and female college students (aged 19–23 years) at a university in south-eastern Nigeria. The participants discussed the popularity of the DGs that students play on this campus, identifying the spaces where each game is played and the motivations for game-playing. Collective, contextual constructions of gender identities through ‘Fastest-Drinker’ DG were identified, and the participants also performed gender through ‘Truth-or-Dare’ and ‘Endurance’ DGs. Men dominated ‘First-to-Finish’ DGs, which are played at parties and bars, and consumed beer or stout, while women, who mainly played Truth-or-Dare games, drank spirits or sweetened alcoholic beverages. Boredom and fun seeking provoked game-playing among women while adherence to masculinity norms, which engendered the public performance of masculinity and gambling activities, motivated men to play DGs. To avoid ‘collective shame’, mens friendship groups provided support/care for inebriated game-playing members, but the immediacy of this support/care varied according to DGs type. DGs appear to normalize heavy drinking and the culture of intoxication on this campus. Measures to monitor alcohol sales outlets around campuses and interventions that target students' leisure spaces should be developed.

Experimentally induced states of mind determine abstinent smokers' level of craving in reaction to smoking-cues

Scipedia content — Fri, 26 May 2017 11:05:25 +0200

The present study aims to contribute to our knowledge on the causes of variations in experienced craving of (ex)smokers. The general idea is tested that when (ex)smokers are exposed to a smoking-cue, their level of craving is determined by the momentary state of mind through which the smoking-cue is interpreted. A cue-reactivity paradigm in temporary abstinent smokers is applied to trigger craving responses under different experimentally induced states of mind. Craving is assessed with a three-item self-report measure. In study 1 (N = 120) a self-affirmation procedure is applied right before abstinent smokers were exposed to their own smoking paraphernalia. In study 2 (N = 140) abstinent smokers received bogus feedback inducing a high or low self-efficacy and strong or weak positive outcome expectations. Study 1 showed a significant interaction: When involvement was high, self-affirmation increased the level of craving but when involvement was low self-affirmation lowered craving. Study 2 also showed a significant interaction: Only when the positive outcome expectation of smoking were high, self-efficacy lowered the level of craving. All analyses were controlled for the number of cigarettes smoked a day and number of past quit attempts. The present studies provide experimental evidence that levels of craving can be determined by momentary states of mind. This theoretical perspective can be integrated in existing conditioning and social cognitive learning perspectives on craving and substance use.

Prevalence and characteristics of addictive behaviors in a community sample: A latent class analysis

Scipedia content — Fri, 26 May 2017 11:05:19 +0200

While addictions to substances such as alcohol, tobacco, and other drugs have been extensively investigated, interest has been growing in potential non-substance-related addictive behaviors (e.g., excessive gambling, buying or playing video games). In the current study, we sought to determine the prevalence and characteristics of a wide range of addictive behaviors in a general population sample and to identify reliable subgroups of individuals displaying addictive behaviors. Seven hundred seventy participants completed an online survey. The survey screened for the presence and characteristics of the main recognized substance and behavioral addictions (alcohol, tobacco, cannabis, other drugs, gambling, compulsive shopping, intensive exercise, Internet and mobile phone overuse, intensive work involvement, and overeating) in a three-month period. Key aspects of addiction were measured for each reported behavior, including negative outcomes, emotional triggers (positive and negative emotional contexts), search for stimulation or pleasure, loss of control, and cognitive salience. Latent class analysis allowed us to identify three theoretically and clinically relevant subgroups of individuals. The first class groups problematic users, i.e., addiction-prone individuals. The second class groups at-risk users who frequently engage in potentially addictive behaviors to regulate emotional states (especially overinvolvement in common behaviors such as eating, working, or buying). The third class groups individuals who are not prone to addictive behaviors. The existence of different groups in the population sheds new light on the distinction between problematic and non-problematic addiction-like behaviors.

Self-control, future orientation, smoking, and the impact of Dutch tobacco control measures

Scipedia content — Fri, 26 May 2017 11:05:14 +0200

The pronounced discrepancy between smokers' intentions to quit and their smoking behavior has led researchers to suggest that many smokers are time inconsistent, have self-control problems, and may benefit from external efforts to constrain their consumption. This study aims to test whether self-control and future orientation predict smoking levels and to identify if these traits modify how cigarette consumption responds to the introduction of tobacco control measures. A sample of Dutch adults (N = 1585) completed a measure of self-control and the Consideration of Future Consequences Scale (CFCS) in 2001 and indicated their tobacco consumption each year from 2001 to 2007. In 2004, a workplace smoking ban and substantial tax increase on tobacco was introduced in the Netherlands. To identify the potential impact of these tobacco control measures we examined whether participants smoked or were heavy smokers (20 + cigarettes per day) each year from 2001 to 2007. Participants with high self-control and CFCS scores showed lower rates of smoking across the seven year period of the study. The 2004 smoking restrictions were linked with a subsequent decline in heavy smoking. This decline was moderated by self-control levels. Those with low self-control showed a large reduction in heavy smoking whereas those with high self-control did not. The effects were, however, temporary: many people with low self-control resumed heavy smoking 2–3 years after the introduction of the tobacco restrictions. The immediate costs which national tobacco control measures impose on smokers may assist smokers with poor self-control in reducing their cigarette consumption.

Free will in addictive behaviors: A matter of definition

Scipedia content — Fri, 26 May 2017 11:05:09 +0200

Certain people are at risk for using alcohol or other drugs excessively and for developing problems with their use. Their susceptibility might arise from a variety of factors, including their genetic make-up, brain chemistry, family background, personality and other psychological variables, and environmental and sociocultural variables. Moreover, after substance use has become established, there are additional cognitive-motivational variables (e.g., substance-related attentional bias) that contribute to enacting behaviors consistent with the persons motivation to acquire and use the substance. People who are at such risk are likely to choose to use addictive substances even though doing so entails negative consequences. In the sense of complete freedom from being determined by causal factors, we believe that there is no such thing as free will, but defined as ability to make choices from among multiple options, even though the choices are ultimately governed by natural processes, addicted individuals are free to choose. Although they might appear unable to exercise this kind of free will in decisions about their substance use, addictive behaviors are ultimately always goal-directed and voluntary. Such goal pursuits manifest considerable flexibility. Even some severely addicted individuals can cease their use when the value of continuing the use abruptly declines or when the subjective cost of continuing the use is too great with respect to the incentives in other areas of their lives. Formal treatment strategies (e.g., contingency management, Systematic Motivational Counseling, cognitive training) can also be used to facilitate this reversal.

Desire thinking as a mediator of the relationship between novelty seeking and craving

Scipedia content — Fri, 26 May 2017 11:05:03 +0200

The construct of craving has been shown to play a crucial role in the development and maintenance of addictive behaviors. Both novelty seeking and desire thinking have been identified, respectively, as important temperamental and cognitive predictors of craving. In the present study we aimed to explore the relative contribution of novelty seeking and desire thinking towards craving, hypothesizing a sequence of multiple mediating relationships starting from novelty seeking and moving onto imaginal prefiguration, verbal perseveration and craving in serial fashion. A convenience sample of 270 individuals completed measures assessing novelty seeking, desire thinking, and craving relating to a chosen activity. Findings showed that, controlling for age and gender, desire thinking components predicted craving over and above novelty seeking. The indirect effect from novelty seeking to craving, via desire thinking components, was significant thus supporting a multiple-mediational sequence. Finally, the relationship between imaginal prefiguration and craving was found to be partially mediated by verbal perseveration. The findings provide support for the conceptualization of desire thinking as an independent construct in predicting craving over and above novelty seeking.

Satisfying needs through Social Networking Sites: A pathway towards problematic Internet use for socially anxious people?

Scipedia content — Fri, 26 May 2017 11:04:58 +0200

Following the theoretical frameworks of the dual-factor model of Facebook use and the Self Determination Theory, the present study hypothesizes that the satisfaction of unmet needs through Social Networking Sites (SNSs) may represent a pathway towards problematic use of Internet communicative services (GPIU) for socially anxious people. Four hundred undergraduate students (females = 51.8%, mean age = 22.45 + 2.09) completed three brief scales measuring the satisfaction via SNSs of the need to belong, the need for self-presentation and the need for assertiveness, the Generalized Problematic Internet Use Scale 2 and the Social Interaction Anxiety Scale. Structural equation modeling was performed separately for males and females. A direct effect of social anxiety on GPIU was found among both genders. Socially anxious males and females tend to use SNSs for self-presentation purposes, as well as for the opportunity to be more assertive. The association between social anxiety and GPIU was partially mediated by the need for self-presentation only among males. The present results extend our understanding of the development of problematic use of Internet communicative services, based on the framework of the dual factor model of Facebook use and the Self Determination Theory. The fulfillment of an unmet need for self-presentation (i.e. the desire to create a positive impression of ones self in others) through SNSs could be one of the possible pathways to GPIU for socially anxious males.

The moderating role of smoking amount per day on the relations between anxiety sensitivity, smoking dependence, and cognitive–affective aspects of smoking among treatment seeking smokers

Scipedia content — Fri, 26 May 2017 11:04:53 +0200

The current study examined the moderating effects of smoking amount per day on the relation between anxiety sensitivity and nicotine dependence, cigarette smoking outcome expectancies, and reasons for quitting smoking among 465 adult, treatment-seeking smokers (48% female, Mage = 36.6, SD = 13.5). Smoking amount per day moderated the relation between anxiety sensitivity and nicotine dependence, smoking expectancies for negative consequences and appetite control as well as intrinsic reasons for quitting. However, no moderating effect was evident for negative reinforcement expectancies. The form of the significant interactions indicated across dependent variables lower levels of smoking amount per day suppressed the relation between anxiety sensitivity and smoking related dependent variable, such that the positive relation of anxiety sensitivity to smoking dependence and cognitive–affective aspects of smoking is weaker in heavier smokers and more robust in lighter smokers.

Which facets of impulsivity predict binge drinking?

Scipedia content — Fri, 26 May 2017 11:04:47 +0200

Impulsive binge drinking is a serious public health issue, and to reveal predisposing factors to this consumption pattern is, therefore, required. Impulsivity-related traits are important predictors of alcohol use and abuse. Nonetheless, previous research in binge drinking has been confounded by various definitions and cut-off scores, implying that existing studies contributed to limited comprehension on the specific role of different impulsivity facets. The current study thus disentangles the role of impulsivity facets in binge drinking by adopting a dimensional approach, considering the condition on a continuum, to avoid relying on debatable and non-definitive criteria. 162 students underwent assessment of alcohol consumption, including drinking patterns and impulsive traits, as captured in the UPPS-P framework (i.e., negative urgency, positive urgency, sensation seeking, lack of perseverance, lack of premeditation). Multiple regression analyses were utilized in order to investigate the predictive role of each impulsivity facet in binge drinking. Binge drinking was associated with sensation seeking. However, when statistically controlling for gender, age and global alcohol consumption, this effect disappeared, and negative urgency remained the only impulsivity component that significantly predicted binge drinking. We found the severity of binge drinking to be associated with negative urgency, suggesting that the binge drinking pattern is displayed in reaction to negative emotional states, and can be conceptualized as a maladaptive and short-term emotional coping. The study calls for prevention and treatment interventions designed to improve self-control, and more adaptive emotion regulation strategies.

Categories of alcohol outcome expectancies and their relationships to alcohol related consequences

Scipedia content — Fri, 26 May 2017 11:04:41 +0200

Extensive research has generally supported a significant and positive relationship of positive outcome expectancies with the amount of alcohol consumed among young adult drinkers, a group generally considered at high risk. Researchers have also naturally been interested in the relationships between these beliefs about drinking and the negative consequences experienced among those who abuse alcohol. Interestingly, those studies found significant positive associations of the number of alcohol outcome expectancies with drinking related consequences, independent of the amount of alcohol being consumed, suggesting that some consequences may be a function of beliefs rather than chemical effects. In addition, there has been evidence that age related differences may exist in the experience of positive outcome expectancies and their associations with consumption. One area that has not been examined is how different categories of alcohol outcome expectancies may be associated with different types of consequences among young adults. Young adults between ages 18–30 were assessed for different categories of alcohol outcome expectancies as well as different types of alcohol consequences. Study hypotheses were partially supported in that specific categories of expectancies were significantly associated with different types of consequences in multiple regression models, but not in the pattern that was predicted from a review of the literature. Expectancies with themes of personal power were consistently found to be significantly and positively associated with various types of consequences after controlling for alcohol consumption. The paper discusses the clinical relevance of these findings with regard to young adult drinkers.

“I cannot stand the boredom.” Binge drinking expectancies in adolescence

Scipedia content — Fri, 26 May 2017 11:04:36 +0200

Introduction: The main aim of this study is to improve our knowledge on binge drinking behavior in adolescents. In particular, we tested a model of predictors of binge drinking focusing on boredom proneness, we also examined the predictive and mediating role of drinking expectancies on binge drinking. Methods: A questionnaire designed to assess current drinking behavior, such as binge drinking, drinking expectancies and boredom proneness, was administered to 721 Italian adolescents (61% females) aged between 13 and 19 years (M = 15.98, SD = 1.61). Results: Structural equation modeling confirmed the evidence on drinking expectancies as predicted by boredom proneness and as predictive of adolescents' binge drinking. Interestingly, disinhibition and relief from pain seem to play a more important mediating role between boredom and alcohol outcome. Conversely, no mediation was found for interpersonal and social confidence expectancies on binge drinking. Conclusions: In general, the results suggest that preventative interventions on alcohol misuse should focus on personality traits and underlying drinking expectancies.

Exercise addiction in CrossFit: Prevalence and psychometric properties of the Exercise Addiction Inventory

Scipedia content — Fri, 26 May 2017 11:04:29 +0200

CrossFit is a mix of aerobic and anaerobic exercise regimes with the stated goal of improving fitness and physical performance. It is growing in popularity and has a strong community known to motivate and push the participants to maximal performance. The negative consequences of these extreme exercise patterns have rarely been described. The prevalence of injuries in CrossFit is high but exercise addiction and harmful exercise attitudes have not yet been assessed. The aim of this study was to measure the prevalence of exercise addiction in CrossFit and to evaluate the reliability and validity of the Exercise Addiction Inventory (EAI) in a CrossFit population. We invited crossfitters to participate in an online survey using Facebook groups. A total of 603 regular crossfitters completed the EAI and additional questions concerning exercise amounts and negative exercise attitudes and beliefs. We used principal component analyses and structural equation models to test the psychometric properties of the EAI and to describe the characteristics of the addicted crossfitters. We found that 5% of the crossfitters were addicted to exercise and that young males had a higher risk. The EAI had good internal reliability (0.73) and construct validity. Thus we found significant positive associations between exercise addiction and the tendency to exercise in spite of injury, feelings of guilt when unable to exercise, passion turning into obsession and taking medication to be able to exercise. Exercise addiction is prevalent in CrossFit and needs further exploration. The EAI is recommended for research in CrossFit communities and applied settings.

Gender differences in felt stigma and barriers to help-seeking for problem gambling

Scipedia content — Fri, 26 May 2017 11:04:22 +0200

Men and women differ in their patterns of help-seeking for health and social problems. For people experiencing problem gambling, feelings of stigma may affect if and when they reach out for help. In this study we examine mens and womens perceptions of felt stigma in relation to help-seeking for problematic gambling. Using concept mapping, we engaged ten men and eighteen women in group activities. We asked men and women about their perceptions of the pleasurable aspects and negative consequences of gambling, they generated a list of four hundred and sixteen statements. These statements were parsed for duplication and for relevance to the study focal question and reduced to seventy-three statements by the research team. We then asked participants to rate their perceptions of how much felt stigma (negative impact on ones own or familys reputation) interfered with help-seeking for gambling. We analyzed the data using a gender lens. Men and women felt that shame associated with gambling-related financial difficulties was detrimental to help-seeking. For men, the addictive qualities of and emotional responses to gambling were perceived as stigma-related barriers to help-seeking. For women, being seduced by the ‘bells and whistles’ of the gambling venue, their denial of their addiction, their belief in luck and that the casino can be beat, and the shame of being dishonest were perceived as barriers to help-seeking. Efforts to engage people who face gambling problems need to consider gendered perceptions of what is viewed as stigmatizing.

Addiction, cigarette smoking, and voluntary control of action: Do cigarette smokers lose their free will?

Scipedia content — Fri, 26 May 2017 11:04:16 +0200

Opinions differ widely as to whether addicts lose the ability to control their behavior and employ free will. This article reviews empirical findings regarding multiple questions relevant to the issue of free will among addicted smokers: Is smoking voluntary behavior? Can people quit smoking? Why don't people quit smoking? Why do smokers relapse when they try to quit? Do addicted smokers suffer from irresistible cravings? Are there some people who cannot quit? Are there conditions that make resistance impossible? Why would they smoke knowing it can kill them? The evidence reviewed here seems most consistent with the view that smokers retain control over their actions but cannot easily stop having frequent desires to smoke.

Hopelessness and alcohol use: The mediating role of drinking motives and outcome expectancies

Scipedia content — Fri, 26 May 2017 11:04:10 +0200

Heavy drinking is a considerable public health concern. There is a broad evidence-base examining the separate contributions of personality characteristics, motives and alcohol-expectancies on subsequent alcohol use to identify those at risk. However, little is known about the complex relationships by which these variables may interact to predict drinking behavior. Feelings of hopelessness and anxiety sensitivity are hypothesized to be distal predictors of alcohol use, with outcome expectancies and drinking motives more proximal. Therefore, the aim of the current study was to examine whether hopelessness and anxiety sensitivity influenced alcohol use via drinking to cope and alcohol - outcome expectancies. We recruited 230 participants to complete an online questionnaire consisting of the brief drinking motives questionnaire, the Substance Use Risk Profile scale and Brief Comprehensive Effects of Alcohol scale. We conducted path analyses using structural equation modelling. We demonstrated a significant direct effect of anxiety sensitivity on alcohol use, and a significant serial indirect effect of hopelessness through coping motives and alcohol outcome expectancies. These findings suggest feelings of hopelessness may predict alcohol consumption through a complex pathway and future research should use these findings to identify individuals at risk of increased alcohol use.

Testing a frequency of exposure hypothesis in attentional bias for alcohol-related stimuli amongst social drinkers

Scipedia content — Fri, 26 May 2017 11:04:05 +0200

To examine whether a group of social drinkers showed longer response latencies to alcohol-related stimuli than neutral stimuli and to test whether exposure to 1) an alcohol-related environment and 2) consumption related cues influenced the interference from alcohol-related stimuli. A 2 × 2 × 2 × 5 factorial design with Exposure Group (high, low) and Consumption Group (high, low) as between-participant factors and Word Type (alcohol, neutral) and Block (1–5) as within-participant factors was used. Forty-three undergraduate university students, 21 assigned to a high exposure group and 22 to a low exposure group, took part in the experiment. Exposure Group was defined according to whether or not participants currently worked in a bar or pub. Consumption Group was defined according to a median split on a quantity–frequency measure derived from two questions of the Alcohol Use Disorders Identification Test (AUDIT) questionnaire. A modified computerised Stroop colour naming test was used to measure response latencies. Exposure and consumption factors interacted to produce greater interference from alcohol-related stimuli. In particular, the low consumption group showed interference from alcohol-related stimuli only in the high exposure condition. Exposure did not affect the magnitude of interference in the high consumption group. Attentional bias is dependent upon exposure to distinct types of alcohol-related cues.

Epidemiology of alcohol use in the general population of Togo

Scipedia content — Fri, 26 May 2017 11:03:59 +0200

Alcohol use is responsible for a high level of mortality and morbidity throughout the world. The WHO global strategy recommends that the detrimental effects of alcohol use be reduced. The objective of this paper was to investigate, using data from the 2010 Togo STEPS survey, alcohol use and other health-related factors in the general population of Togo. This epidemiological investigation using the STEPwise approach was undertaken from December 1st, 2010, to January 23rd, 2011, throughout the five regions of Togo. Togo is a low-income country (World Bank) located in West Africa. The study involved 4800 people aged 15 to 64 who were representative of the population of Togo and who were selected using the one-stage cluster sampling method. The sample was young and predominantly male. Approximately one-third of the respondents were alcohol abstainers, with the majority of these being women. Approximately the same proportion of current drinkers (daily consumption) by gender was observed. The reported daily average consumption of alcohol was 13 g of pure alcohol for men and 9 g for women. The mean number of heavy drinking days over the previous 30 days was higher for men (3 days), and this included 37.5% of the men who drink. We suggest a comparative analysis of the prevalence of harmful alcohol use in Togo and the WHO African region.

Social determinants of HIV/HCV co-infection: A case study from people who inject drugs in rural Puerto Rico

Scipedia content — Fri, 26 May 2017 11:03:53 +0200

A new strategy for thevulnerability study of buildings exposed to open-airexplosions

Scipedia content — Thu, 25 May 2017 15:03:03 +0200

In this paper, a new methodology is described to evaluate the effect of open air explosions on equivalent structures to the facades of buildings. The structural damage is defined by vulnerability surfaces that are a function of the explosion magnitude, the distance to the structure and the detonation damage index developed in this article. The proposed index considers the structural load capacity degradation, the fracturing and the loss material due to the explosion. The structure is modeled by means of discrete elements (DEM) which allows describing the multifracturing state. The load capacity of the structure is quantified by a virtual compression test on the damaged structure. The forces on the structure caused by the explosion are modeled by a semi-empirical methodology, which avoids the fluid-dynamic analysis and reduces the computation time.

Assesment of the behavior factor prescribed by the Ecuadorian Construction Code for steel framed structures

Scipedia content — Thu, 25 May 2017 15:02:50 +0200

Incremental Dynamic Analysis (IDA) has been applied lately in order to evaluate the maximum lateral strength of buildings under variable seismic intensity. This variation on intensity is achieved by means of the progressive scaling of the amplitudes of the dynamic signal imposed to the models of the buildings. This numerical procedure was used in order to assess the seismic performance, via the assessment of the behavior factor q (used in many seismic codes worldwide) of the recent version of the Ecuadorian Construction Code. Likewise, the used approach is based on the adaptation of the FEMA P-695 Methodology including issues like the seismic input selection and the definition of the collapse threshold. In order to perform the above mentioned assessment, a set of archetypes representatives of the design space have been defined. These archetypes were designed according three different procedures: acceleration-based and displacement-based procedures and an energy-based alternative procedure. Results depict that some of the adopted values for the behavior factor does not fulfill the requirements of the methodology used, so the design is not able to guarantee an adequate performance of the buildings when they withstand destructive earthquakes.

Numerical analysis of an anomalous diffusion with a bimodal flux distribution

Scipedia content — Thu, 25 May 2017 15:02:16 +0200

A numerical study of unidimensional and steady state bimodal flux diffusion equation has been developed using the Finite Volume Method. In addition, with the Ficks flux, this equation has another flux named retention or secondary flux. The influence of each flux has been analysed in this work. The influence of several different parameters, such as boundary conditions or amplitude and frequency of the solution, in the numerical errors has been studied. Numerical results show the performance of the proposed model.

MOHID platform automaticcalibration employing a stochastic optimization method and realdata from an extreme climate event in Nova Friburgo‐RJ: Part2–sensitivity analysis and hydrological parameters estimation

Scipedia content — Thu, 25 May 2017 15:02:04 +0200

This is the second of two complementary articles that deal with the implementation of an automatic calibration routine coupled to a simulation model of runoff and hydraulic behavior of the drainage system of a watershed during flood events, built in the water Modeling System MOdelo HIDrodinâmico (MOHID). As a case study two watersheds located in the city of Nova Friburgo, State of Rio de Janeiro were analysed. This second article discusses the pertinent aspects related to the inverse problem technique and the coupling of MOHID platform to Luus‐Jaakola optimization method, aiming to estimate some of the key parameters required for modeling the drainage in watersheds and the flow in channels. The adopted strategy proved very effective in its ability to estimate the parameters which led to a satisfactory agreement between simulated and observed water levels at stations located along the studied rivers.

MOHID platform automatic calibration employing a stochastic optimization method and real data from an extreme climate event in Nova Friburgo‐RJ: Part1–digital terrain model preparation and processing of rainfall and level experimental data

Scipedia content — Thu, 25 May 2017 15:01:55 +0200

This is the first of two complementary articles that deal with the implementation of an automatic calibration routine coupled to a simulation model of runoff and the flow of two urban watersheds, both located in the city of Nova Friburgo, State of Rio de Janeiro, Brazil. The models were built in the MOHID Waters Modelling System. This first part presents the methodology of the construction of the Digital Terrain Model–DTM and the drainage network of the studied watersheds, made in the MOHID platform, as well as the acquisition of actual rainfall data and water levels through the site of the Instituto Estadual do Ambiente–INEA. The results were compared with ArcMap software and showed a good agreement regarding the delimitation of watersheds and the drainage network.

Evaluation of structural stress method and master curve for fatigue life prediction of a welded joint

Scipedia content — Thu, 25 May 2017 15:01:34 +0200

This paper presents a study on the structural hot spot stress method and the master curve method (Battelle) for evaluating the fatigue life of a T‐shaped welded joint. Both methods are based on the concept of structural stress, which is usually determined using finite element models. Using different types of shell finite element models, the results obtained by the two methods were compared to experimental data, verifying significant differences between the studied methods. The loading level had a great deal of influence over the accuracy of both methodologies, but on the other hand the hot spot method revealed to be more precise for the analyzed joint. The main differential for the Batelle method was the correction of the stress amplitude into an equivalent structural stress parameter, since, without this correction, the stresses on the weld toe were very similar between the Battelle and the hot spot methods. Comparing the master curve for the fatigue behavior of the Battelle method to the fatigue curve of hot spot method, with both curves expressed in terms of the nominal stress applied in the experiment, it was verified that the hot spot method is conservative. Among the different modeling techniques used, only one provided results that are not in agreement with the others. Using the Battelle method, the behavior of the bending stress component varied considerably according to the employed numerical model, indicating that can be a greater variability in the expected fatigue life for joints under more complex loading configuration.

Analysis of columns with shear deformation using finite element method and equivalent distributed loads

Scipedia content — Thu, 25 May 2017 15:01:01 +0200

This paper describes a procedure based on the concept of Equivalent Distributed Loads (EDL) applied to the Finite Elements Method (FEM) based on displacements and exact nodal solution of columns subject to shear deformation in accordance with the Timoshenko beam theory. The results obtained using this “EDL-FEM” methodology, in the cases studied, show that a high level of exactness in displacements, rotations as well as shear force and bending moment is obtained with a very small number of elements (one or two in the examples developed). Other methodologies based on displacements, such as reduced integration, require on the order of 40 elements to achieve similar results. The stability functions and buckling load for the Timoshenko beam are also determined in a direct and systematic way from the FEM with exact nodal solution.

Simulation of a cross-flow air classifier at high solid feed rates

Scipedia content — Thu, 25 May 2017 15:00:51 +0200

The cross-flow air classifier is a dry process device. The use of such separators is being evaluated to replace the wet classification methods in the production of manufactured sand. The influence of the solid feed rate is critical for the correct design of the process. One method to analize the influence of the feed is by using numerical simulation. In this work, the powder classification process is simulated by computational fluid dynamics (CFD). The particle-particle interaction is modeled with a discrete element method (DEM). Simulations are optimized to better represent the experimental data by choosing between two turbulence models and two models for the injection of solids. Dust classification at three different solid rates is simulated. It is established that the amount of solids has a great influence in the classification process. This fact indicates that the solids content is a critical parameter for a proper design of the device.

Computational fluid dynamics simulation of cooling system for copper smelter gases by Teniente Converter with evaporative cooler

Scipedia content — Thu, 25 May 2017 15:00:40 +0200

In the copper sulfides smelting process, the Teniente-type converter generates highly corrosive and toxic gases, which is why treating them is crucial in order to avoid environmental damage. The present study proposes a new methodology to simulate the capture and cooling system of smelting gases through the application of Computational Fluid Dynamics (CFD) to the gases that emanate from a Teniente-type converter, where a series of assumptions that allow the adaptation of the physical model for the CFD simulation are proposed along with the validation of the results using real industrial-scale instruments. By applying this method, it is possible to obtain a behavioral simulation model of the smelting gases with an acceptable relative error. In practical terms, this means that the tendencies that metallurgical gases show in the simulation flowing through the bell and the cooling chamber can be trusted to predict the thermal behavior of the gases contained in the gas management network.

Analysis of the coating integrity during a coronary stent deployment

Scipedia content — Thu, 25 May 2017 15:00:28 +0200

The cardiovascular diseases constitute one of the main causes of death worldwide. One of the main diseases is atherosclerosis, which causes narrowing of the arterial lumen. In order to solve this condition, several treatments have been developed, and Percutaneous Transluminal Coronary Angioplasty (PTCA) with the placement of stent have gained relevancy. Many of these devices are currently coated to increase the biocompatibility and to decrease the restenosis risks. The biomechanical studies of the stent-coating interface behavior are necessary given the associated risks to possibility of failures or breakages of the coating during stent deployment. In this study the possible occurrence of coating delamination during stent deployment and the influence of parameters as the thickness and material were studied. The study starts by obtaining a geometric model of a stent unit of the Sirius Carbostent stent for the further processing by the Finite Element Method. The simulation was developed by applying restrictions so that the modeled stent hinge simulates his behavior during stent deployment. Considering these aspects it was possible to evaluation the coating integrity. With this model it was possible to predict the occurrence of delamination during stent deployment and to determine that the delamination risks increases with increasing the coating thickness. Finally, it was obtained a general function that allows to determine the maximal contact stress for a stent hinge with an U shape.

Comparative analysis between the maxent and the weighted least square shape functions in a collocation meshless method

Scipedia content — Thu, 25 May 2017 15:00:02 +0200

In this article the behavior of a shape function based on the maximum entropy principle (maxent) is analyzed in a meshless collocation method, compared with a traditional fixed weighted least square shape function (FWLS). The maxent shape function used in this work has certain properties that are desired in a meshless collocation method, for example the positivity, the smooth and uniform aspect for different discretizations. Further, in the boundary, the approximation not depends of the shape function of the interior nodes, this property is know as a reduction of the shape function on the boundary. To compare this type of function, it was developed examples that include the solution of eliptical second order equations in 1D and 2D. The numerical results shown a better behavior of the maxent shape function compared with the FWLS, particularly in terms of the convergence and stability of the meshless collocations method that result.

Numerical analysis of gas-solids flow hydrodynamics and heat transfer in two outlet configuration industrial riser using mesoscale theory to predict the interfacial drag

Scipedia content — Thu, 25 May 2017 14:59:44 +0200

In the FCC process two configurations riser are numerically analyzed varying the upper outlet orientation using a 2 D CFD model which includes the Two Fluid Model (TFM), Kinetic Theory of Granular Flow (KTGF), and Energy Minimization Multi-Scale (EMMS) theory as drag model. This model is solved using the ANSYS Fluent® 14.5 software, solving the governing equations of mass, momentum, and energy balance, and the constitutive equations to calculate interfacial interaction, wall-solid phase interaction, and granular phase properties. The model proposed in this work properly predicts the gas-solid flow behavior, predicting different solid flow patterns in radial and axial riser directions, as well as concentrated and diluted zones at risers top and bottom respectively. The radial and axial solids concentration and velocities profiles fluctuations observed are produced by the high radial solid mix which is higher near the riser walls due to drag force considered by the model used. On the other hand, a rapid radial and axial thermal stabilization is observed reaching the steady state rapidly. The profiles obtained from riser configurations analyzed are very similar, so in future works other riser outlets configurations will be analyzed to try to improve the solid concentration and velocity profiles.

Study of the process of combustion in a high swirl engine using computational fluid dynamics

Scipedia content — Thu, 25 May 2017 14:59:32 +0200

The numerical simulation of spark ignition engines has uncertainties that compromise the reliability of the results due to the interrelationship between chemical dynamics and flow kinematics within the combustion chamber. This work evaluated the effect of using different reaction mechanisms applied to a G-equation combustion model and its interaction with the velocity field inside the combustion chamber of a CFR engine, which has special technical characteristics (high swirl and low rpm) that allowed the study of this phenomenon. The research was carried out numerically by computational fluid dynamics (CFD) techniques: using a G-equation combustion model (with and without reaction kinetics) and a RANS -k − ϵ- RNG turbulence model. The numerical simulation was compared and validated against reported experimental pressure indicator diagram. The influence of reaction mechanisms and swirl in the development of the flame front and associated variables within the combustion chamber was studied. Finally slight discrepancies were found between reaction mechanisms used in this study that could be important in simulations of spark ignited engines that are different from the one studied. It was noted that an increase in the intensity swirl yields a flame development deviation from the theoretical models. The current codes and simulation techniques require tuning of various parameters, and thus, the validation against experimental data is needed before drawing conclusions from the numerical cases.

A Lagrangian PFEM approach for non-Newtonian viscoplastic materials

Scipedia content — Thu, 25 May 2017 14:59:10 +0200

This paper presents the application of a stabilized mixed Particle Finite Element Method (PFEM) to the solution of viscoplastic non-Newtonian flows. The application of the proposed model to the deformation of granular non-cohesive material is analysed. A variable yield threshold modified Bingham model is presented, using a Mohr Coulomb resistance criterion. Since the granular material is expected to undergo severe deformation, a Lagrangian approach is preferred to a fixed mesh one. PFEM is the adopted technique. The detail of the discretization procedure is presented and the Algebraic Sub-Grid Scale (ASGS) stabilization technique is introduced to allow for the use of equal order interpolations for velocity and pressure in a consistent way. The matrix form of the problem is given. Finally, the differences between the regularized Bingham and the variable yield models are discussed in some examples.

A stabilized mixed explicit formulation for plasticity with strain localization

Scipedia content — Thu, 25 May 2017 14:58:49 +0200

This paper presents the application of stabilized mixed explicit strain/displacement formulation (MEX-FEM) [23, 24] for solving non-linear plasticity problems in solid mechanics with strain localization. In order to use the same linear interpolation order for displacements and strains, the formulation uses the variational subscales method. Compared to the standard irreducible formulation, the proposed formulation yields improved strain and stress fields, and it is capable of addressing nearly incompressible situations. This work investigates the effects of the improved strain and stress fields in problems involving strain softening and localization leading to failure for the Mohr-Coulomb and Drucker Prager plasticity models. Numerical examples validate the ability of the proposed formulation to correctly predict failure mechanisms with localized patterns of strain, virtually free of mesh dependence and without using tracking algorithm.

Comparison of the estimated modal parameters of structures from classical and operational modal analysis with mass changes

Scipedia content — Thu, 25 May 2017 14:58:39 +0200

The lack of standardization in vibration mode results has constituted the main shortcoming of operational modal analysis, subsequently resolved by means of the mass modification method. This is a major drawback for civil works, as it interrupts traffic on site, significantly increasing testing time and costs. The purpose of this study is to achieve a balance between traditional modal analysis (accompanied by numerical simulations of mass modification) and operational modal analysis (in conjunction with the mass modification method), thereby obtaining more optimal results with a narrower range of error, even when the signal has a high level of noise. It will thus be possible to reliably determine the modal parameters of the structure and their alteration due to mass modification. For this purpose, the proposed methodology is applied to a large span metal bridge, unique for its slenderness, with a span/depth ratio of 56.6, the lowest recorded on a bridge, as figured in the Guinness Book of Records since 2007.

Change point algorithms applied to the detection of vortex structures in turbulent flows

Scipedia content — Thu, 25 May 2017 14:58:30 +0200

The present work shows the application of a change point model (CPM) algorithm, based on non-parametric tests, to turbulent structures detection in an airflow. It seeks to detect the vortices generated in the wake of an airfoil, equipped with a passive flow control device (Gurney mini flap) in its trailing edge. By applying CPM models to the sample data, this paper seeks to determine the possible changes to the velocity fluctuations and compare the models effectiveness to traditional methods. The main objective of this study is to detect the characteristic frequencies of the turbulent structures immersed in the airflow. The results show that the CPM methodology, based on the Cramer- von Mises (CPM-CvM) test, produces results that coincide with values predicted by traditional methods (less than 9.5% of mismatch), validating its use as a real time alternative tool for the analysis of these types of flows. Finally, this work shows a new application of CPM for detecting changes in a time-dependent random signal, which has an a priori unknown distribution.

Estimation of modal parameters ofcivil structures from frequency response function

Scipedia content — Thu, 25 May 2017 14:58:18 +0200

This paper focuses on estimating the modal parameters of the dynamic system that constitutes the pedestrian footbridge of the Science Museum of the city of Valladolid (Spain). The work consists not only of calculating natural frequencies and damping factors associated to each of the estimated modes, as many commercial software provide from acceleration measurements of tests OMA (Operational Modal Analysis) and/or EMA (Experimental modal Analysis), but the aim of this paper is to calculate the generalized masses corresponding to each of the estimated modes of the structure. For this purpose, firstly a representation of the dynamic system is obtained in the state space by SSI technique (Stochastic Subspace Identification), and secondly, vibration modes are scaled from the estimation of the residues of the decomposition in partial fractions of the frequency response function (FRF) measurements. This method gets accurate estimations in the results whose vibration modes are excited, allowing the simulation of the dynamic response of the structure without the need for updating a finite element model of the structure under study.

Analysis of structure withdissipator spectra under design and control

Scipedia content — Thu, 25 May 2017 14:58:02 +0200

The structures of Quito, Ecuador, are designed for the spectrum of the Ecuadorian code of 2015, or using the study of microzoning of the city of 2012. These spectra consider in general the effect of the blind reverse faults belonging to the city area. In this article, it is pointed out the importance of checking the design for the deterministic control spectra developed for Quito in 2015 based on earthquakes simulated in the blinds faults. In this paper we considered two models of extended plasticity for the structural elements and one model of plasticity for the ADAS and TADAS devices. Then, the technique of multimodal pushover is described, as well as the method of the capacity spectrum used to calculate the performance point of the structure. This structure was initially calculated by using design spectra and it had to be reinforced with ADAS devices in order to avoid its collapse for the control spectrum which has higher ordinates than the design one.

中医阴阳五行描述了信号分子的传输通路

Yang Liu — Tue, 23 May 2017 09:51:02 +0200

信号分子在生命过程中起着重要作用，它的传输通路对调节生理功能和病理的发展具有决定性作用。但是我们对这些通路的认识仍不全面。中医用阴阳五行来描述人体内的生理过程，但至今还没找到科学依据支持中医理论。黄帝内经认为心肝脾肺肾（五行）各有其阳阴气，并指出了每个“行”的生理功能和五行之间的相互关系。我们用迭代筛选法，将信号分子与黄帝内经所列各“行”的生理功能和相互关系一一比较，找出了五行中阳阴气与信号分子之间的直接映射，而满足这些关系的概率大概为十万分之二到百万分之一。这使我们发现阴阳五行实际上描述了人体中信号分子的传输通路，中草药的功用是调节各个信号分子。通过这一映射关系，可以清楚地看到现代医学和中医对一些疾病，如血尿、 便秘、 痔病、 遗尿症、 尿频、 胆结石、 急性胆囊炎和高血压，所认定的发病机理和治疗策略是一致的，只是使用了不同的术语。

Traditional Chinese medicine describes the pathways of signaling molecules

Yang Liu — Tue, 23 May 2017 08:20:02 +0200

The pathways of signaling molecules are important to understanding how signaling molecules regulate physiological function and also in predicting the pathological development which is important to therapeutic strategy, however the thorough knowledge of these pathways is still lack. Traditional Chinese medicine (TCM) used Yang and Yin to describe the physiological processes in human body, but its scientific basis is unknown. Here we establish the direct mapping between Yang-Yin and signaling molecules. According to “Yellow Emperor’s Inner Canon” (YEIC), the fundamental doctrinal source for TCM, there are five groups of Yang and Yin, each has particular physiological functions and the different groups have particular relationships. We used the iterative selection method to compare these physiological functions with the functions of signaling molecules, and establish the direct mapping between Yang-Yin and signaling molecules. With the mapping, it is shown that the pathways of these signaling molecules are the same as the dialectical relationships of these Yang-Yins and agree well with TCM therapeutic strategies. The Chinese herbal medicine actually regulates the level of corresponding signaling molecule. With the mapping, it is clearly shown that the modern medicine and TCM identify the same pathogenesis of diseases, such as hematuria, constipation, hemorrhoidal disease, nocturnal enuresis, frequent urination, gall stone, acute cholecystitis and hypertension; and adopt the same treatment strategy. Modern medicine and TCM describes the same physiological process using different terminology. '''Key words''': Signaling molecules, traditional Chinese medicine, pathways, Yang and Yin, therapeutic strategy.

In vivo effects of mid-myocardial pacing on transmural dispersion of repolarization and conduction in canines

Scipedia content — Fri, 19 May 2017 11:54:09 +0200

In our previous in vitro study mid-myocardial relative to epicardial pacing decreased transmural dispersion of depolarization (TDR) and prevented ventricular arrhythmia. We therefore hypothesized that in vivo mid-myocardial pacing in canines has a similar effect. Using custom-made electrodes, monophasic action potentials were simultaneously recorded in vivo from left ventricular epicardial (Epi), mid-myocardial (Mid) and endocardial (Endo) layers of canines (n = 12). TDR was significantly increased at Epi (44.6 ± 6. 4 ms, 14.2 ± 5.1 ms, and 13.8 ± 5.4 ms for Epi, Mid and Endo pacing, respectively, P

Measurement of the blood flow rate and velocity in coronary artery stenosis using intracoronary frequency domain optical coherence tomography: Validation against fractional flow reserve

Scipedia content — Fri, 19 May 2017 11:54:04 +0200

The main objective of this study was to assess the blood flow rate and velocity in coronary artery stenosis using intracoronary frequency domain optical coherence tomography (FD-OCT). A correlation between fractional flow reserve (FFR) and FD-OCT derived blood flow velocity is also included in this study. A total of 20 coronary stenoses in 15 patients were assessed consecutively by quantitative coronary angiography (QCA), FFR and FD-OCT. A percutaneous coronary intervention (PCI) optimization system was used in this study which combines wireless FFR measurement and FD-OCT imaging in one platform. Stenoses were labelled severe if FFR ≤ 0.8. Blood flow rate and velocity in each stenosis segment were derived from the volumetric analysis of the FD-OCT pull back images. The FFR value was ≤ 0.80 in 5 stenoses (25%). The mean blood flow rate in severe coronary stenosis (n = 5) was 2.54 ± 0.55 ml/s as compared to 4.81 ± 1.95 ml/s in stenosis with FFR > 0.8 (n = 15). A good and significant correlation between FFR and FD-OCT blood flow velocity in coronary artery stenosis (r = 0.74, p

Relative diagnostic, prognostic and economic value of stress echocardiography versus exercise electrocardiography as initial investigation for the detection of coronary artery disease in patients with new onset suspected angina

Scipedia content — Fri, 19 May 2017 11:53:58 +0200

We hypothesised that stress echocardiography (SE), may be superior to exercise ECG (ExECG), for predicting CAD and outcome, and cost-beneficial, when performed as initial investigation in newly suspected angina. All patients seen in 2011, with suspected angina, no history of CAD, pre-test likelihood of CAD of > 10% and who underwent SE or ExECG as first line were identified retrospectively. Cost to diagnosis was calculated by adding the cost of all tests, up to and including coronary angiography (CA), on an intention-to-treat basis. Follow-up data on cardiac death and myocardial infarction (MI) were collected, 26 months after the presentation of the last study patient. A total of 456 patients underwent ExECG (224 (49%) negative, 93 (20%) positive, 139 (31%) inconclusive) and 241 underwent SE (200 (83%) negative, 35 (15%) positive, 6 (2%) inconclusive) as first line. In patients subsequently undergoing CA, CAD was present in 46% (37/80) of patients with positive ExECG vs. 72% (23/32) patients with positive SE (p = 0.01). Mean cost to diagnosis was £456 for the ExECG vs. £360 for the SE group (p = 0.002). Over a mean follow-up period of 31 ± 5 months, cardiac events were 2% each in negative SE vs. negative ExECG (p = 0.9). SE is superior to ExECG for prediction of CAD and is cost-beneficial when used as initial test in patients with no history of CAD presenting with suspected angina.

A feasible method for non-invasive measurement of pulmonary vascular resistance in pulmonary arterial hypertension: Combined use of transthoracic Doppler-echocardiography and cardiac magnetic resonance. Non-invasive estimation of pulmonary vascular resistance

Scipedia content — Fri, 19 May 2017 11:53:51 +0200

Transthoracic Doppler-echocardiography (TTE) can estimate mean pulmonary arterial pressure (MPAP) and pulmonary capillary wedge pressure (PCWP) reliably, and cardiac magnetic resonance (CMR) is the best modality for non-invasive measurement of cardiac output (CO). We speculated that the combined use of TTE and CMR could provide a feasible method for non-invasive measurement of pulmonary vascular resistance (PVR) in pulmonary arterial hypertension (PAH). Right heart catheterization (RHC) was undertaken in 77 patients (17M/60F) with PAH, and simultaneous TTE was carried out to evaluate MPAP, PCWP and CO. Within 2 days, CO was measured again with CMR in similar physiological status. Then, PVR was calculated with the integrated non-invasive method: TTE-derived (MPAP–PCWP)/CMR-derived CO and the isolated TTE method: TTE-derived (MPAP–PCWP)/TTE-derived CO, respectively. The PVR calculated with integrated non-invasive method correlated well with RHC-calculated PVR (r = 0.931, 95% confidence interval 0.893 to 0.956). Between the integrated non-invasive PVR and RHC-calculated PVR, the Bland–Altman analysis showed the satisfactory limits of agreement (mean value: − 0.89 ± 2.59). In comparison, the limits of agreement were less satisfactory between TTE-calculated PVR and RHC-calculated PVR (mean value: − 1.80 ± 3.33). Furthermore, there were excellent intra- and inter-observer correlations for the measurements of TTE and CMR (P

Olmesartan reverses not only vascular endothelial dysfunction but cardiac diastolic dysfunction in hypertensive patients with heart failure with preserved ejection fraction — ORION study

Scipedia content — Fri, 19 May 2017 11:53:46 +0200

Could early septal involvement in the remodeling process be related to the advance hypertensive heart disease?

Scipedia content — Fri, 19 May 2017 11:53:40 +0200

Quantitative imaging analyses showed an earlier septal wall involvement in hypertension. We planned to determine the effect of hypertension on regional myocardial performance index (MPI) in a hypertensive patient population. We evaluated 119 hypertensive patients who were divided into gr. I: 57 patients without left ventricular hypertrophy (LVH), (53.1 ± 10 years), and gr. II: 62 patients with LVH (55.1 ± 9 years) using conventional and tissue doppler imaging. They were compared with gr. III, a sex-age-matched normal control group (37 subjects, 53.0 ± 10 years). We detected basal septal and basal lateral contraction time (CT), isovolumetric CT and relaxation time (IVRT) and MPI. EF was 68 ± 5 % in gr. I, 69 ± 5 % in gr. II, 69 ± 4 % in gr. III. LV mass index was 122 ± 11 g/m2 in gr. I, 148 ± 13 g/m2 in gr. II and 118 ± 13 g/m2 in gr. III. Concentric LVH was detected in gr. II (relative wall thickness = 0.49 ± 0.8). LV septal and lateral MPI were abnormal in both hypertensive groups (p

Letter to Editor

Scipedia content — Fri, 19 May 2017 11:53:35 +0200

Long-term dual antiplatelet treatment and bleeding complications in diabetic patients treated with drug eluting stent implantation

Scipedia content — Fri, 19 May 2017 11:53:30 +0200

Dual antiplatelet treatment (DAPLT) for at least 12 months is recommended after drug eluting stent (DES) implantation, but concerns regarding the extended use of this treatment persist due to increased risk of bleeding. In this study are assessed the incidence, correlates, and clinical significance of bleeding complications in diabetic patients after long-term DAPLT post DES implantation. We studied 610 consecutive diabetic patients after DES implantation. The primary end point was the occurrence of any bleeding according to the BARC and TIMI definitions. The incidence of overall bleeding was higher in patients on DAPLT (21.1% vs. 4.4%, p

Carotid intima-media thickness and carotid plaque represent different adaptive responses to traditional cardiovascular risk factors

Scipedia content — Fri, 19 May 2017 11:53:23 +0200

To assess the effects of each traditional cardiovascular risk factor (hypertension, diabetes mellitus, dyslipidemia, and smoking), including the presence of coronary artery disease (CAD), on carotid intima-media thickness (CIMT) and to assess the degree of carotid plaque occurrence. A total of 553 outpatients (216 men and 337 women, mean age 67.06 ± 12.44 years) who underwent a carotid artery ultrasound were screened for carotid plaque and CIMT measurements. The CIMT medians were higher in males (P

Controlled heart rate and blood pressure reduce the life threatening aortic events and increase survival in patients with type B aortic dissection: A single center experience

Scipedia content — Fri, 19 May 2017 11:53:15 +0200

Assessment of various parameters using simple non-invasive tests in patients with cardiovascular diseases with or without cardiac rehabilitation

Scipedia content — Fri, 19 May 2017 11:53:07 +0200

Cardiac rehabilitation (CR) improves cardiac function and exercise capacity in patients with cardiovascular disease (CVD). Simpler techniques are needed for use by physicians in the examination room to assess the usefulness of CR. We enrolled 46 consecutive CVD patients in a CR program (CR group) and prospectively followed them for 3 months. We compared them to 18 age-, gender- and body mass index-matched CVD patients without CR (non-CR group). Various parameters were measured at baseline and after 3 months using 3 simple non-invasive tests: severity of atherosclerosis [arterial velocity pulse index and arterial pressure volume index (API)] were determined using PASESA®, an autonomic nerve total activity amount index and a coefficient of variation of the R–R interval (CVRR) were determined using eHEART®, and peripheral resistance index, pressure rate product, stroke volume and cardiac index were determined using nico®]. There were no significant differences in patient characteristics including percentages (%) of ischemic heart disease and heart failure between the non-CR and CR groups. Systolic blood pressure (SBP), diastolic BP, heart rate and API at baseline significantly decreased and CVRR at baseline significantly increased after 3 months in the CR group, but not in the non-CR group. In addition, ΔAPI (Δ = the value after 3 months minus the value at baseline) was positively associated with ΔSBP in the CR group. In conclusion, CR significantly decreased BP and improved atherosclerosis and sympathetic nerve activity. These findings suggest that simple non-invasive tests may be useful for assessing the effects of CR.

Conduction abnormalities and ventricular arrhythmogenesis: The roles of sodium channels and gap junctions

Scipedia content — Fri, 19 May 2017 11:46:23 +0200

Ventricular arrhythmias arise from disruptions in the normal orderly sequence of electrical activation and recovery of the heart. They can be categorized into disorders affecting predominantly cellular depolarization or repolarization, or those involving action potential (AP) conduction. This article briefly discusses the factors causing conduction abnormalities in the form of unidirectional conduction block and reduced conduction velocity (CV). It then examines the roles that sodium channels and gap junctions play in AP conduction. Finally, it synthesizes experimental results to illustrate molecular mechanisms of how abnormalities in these proteins contribute to such conduction abnormalities and hence ventricular arrhythmogenesis, in acquired pathologies such as acute ischaemia and heart failure, as well as inherited arrhythmic syndromes.

Electrophysiological mechanisms of long and short QT syndromes

Scipedia content — Fri, 19 May 2017 11:46:16 +0200

The QT interval on the human electrocardiogram is normally in the order of 450 ms, and reflects the summated durations of action potential (AP) depolarization and repolarization of ventricular myocytes. Both prolongation and shortening in the QT interval have been associated with ventricular tachy-arrhythmias, which predispose affected individuals to sudden cardiac death. In this article, the molecular determinants of the AP duration and the causes of long and short QT syndromes (LQTS and SQTS) are explored. This is followed by a review of the recent advances on their arrhythmogenic mechanisms involving reentry and/or triggered activity based on experiments conducted in mouse models. Established and novel clinical risk markers based on the QT interval for the prediction of arrhythmic risk and cardiovascular mortality are presented here. It is concluded by a discussion on strategies for the future rational design of anti-arrhythmic agents.

Mitral regurgitation — Unmet need for improved management strategies

Scipedia content — Fri, 19 May 2017 11:46:11 +0200

The management of mitral regurgitation (MR) is challenging — patients may be asymptomatic, oligosymptomatic, older with comorbidities, or clinically symptomatic and not appropriate for surgery. The current review assesses morbidity, mortality, and risk factors associated with functional and organic MR, with a focus on severe MR. A structured literature review was conducted in MEDLINE, Embase, the Cochrane Library, and via hand-searching of conference proceedings. Prospective randomised controlled trials and observational studies including adult patients with MR reporting on treatment response rates, survival, time-to-treatment failure, quality of life, and adverse events were eligible for inclusion. In total, 32 publications met the inclusion criteria (9 in functional, 18 in organic, and 5 in functional/organic). Despite study heterogeneity, an increased risk of mortality and morbidity was observed which increased with MR severity. Risk factors associated with mortality and morbidity included advancing age, presence of atrial fibrillation, increasing effective regurgitant orifice, ejection fraction, left ventricle end systolic diameter, diabetes, and increasing New York Heart Association class. The current review represents one of the most comprehensive conducted in the medical/conservative management of MR. An increased risk of mortality and morbidity, which appeared to rise with greater severity, was associated with MR (versus no MR). An unmet need exists in the management of patients with severe symptomatic MR and a high surgical risk as they have a poor prognosis and limited treatment options. Further research into alternative medical strategies and patient management is needed to improve prognoses and reduce mortality and morbidity.

Chronic total occlusions — Current techniques and future directions

Scipedia content — Fri, 19 May 2017 11:46:00 +0200

Chronic total occlusions (CTOs) of coronary arteries represent a common and significant challenge to interventional cardiology. Medical therapy is often regarded as an adequate long term strategy in the management of these lesions with surgical intervention for refractory symptoms. Extensive collateralisation is used as a marker of distal coronary perfusion, further reinforcing non-invasive strategies. This together with relatively low percutaneous success rates outside of specialised centres has meant that rates of percutaneous intervention have remained low. Increasing evidence suggests that CTOs are not a benign entity. Further, symptom control and quality of life improve significantly with successful percutaneous revascularisation. Both factors have reignited interest in percutaneous modalities. The Japanese have been pioneers in the field of CTO intervention although their success rates have been difficult to replicate. New techniques and equipment developed in North America offer an alternative to the Japanese approach. These techniques focus on time, radiation and contrast minimisation. This review will assess the histopathology of CTO and shifting paradigms in CTO treatment strategies.

QRS complex fragmentation and survival following left ventricular assist device implantation

Scipedia content — Fri, 19 May 2017 11:45:54 +0200

In patients with heart disease, the presence of a fragmented QRS complex (fQRS) on the surface electrocardiogram (ECG) is associated with an increased risk of mortality. We sought to evaluate the prevalence and location of fQRS before and after left ventricular assist device (LVAD) implantation and any associated risk of mortality. Twelve-lead surface ECGs before (pre-LVAD, n = 98) and after (early [

Regression of cardiac amyloidosis following stem cell transplantation: a comparison between echocardiography and cardiac magnetic resonance imaging in long-term survivors

Scipedia content — Fri, 19 May 2017 11:45:48 +0200

AL amyloidosis and multiple myeloma result in extracellular deposition of insoluble fibrillary protein in tissue and organs. Untreated median survival is very poor, and even worse with cardiac involvement. Chemotherapy and peripheral blood stem cell transplantation (PBSCT) have been shown to dramatically improve survival, with hematologic remission documented. Regression of cardiac changes has previously been shown, as assessed by echocardiography (TTE) and cardiac magnetic resonance imaging (CMR). This study is a comparison of TTE and CMR in long-term survivors of cardiac amyloidosis with regression. Four long-term survivors with cardiac amyloidosis and regression of cardiac features on TTE were identified. Mean age was 60 years and average survival was 139 months from the time of diagnosis of cardiac involvement. Statistically significant regression of the cardiac features of cardiac amyloidosis were demonstrated on TTE. In these survivors, post-PBSCT structural assessments were similar between TTE and CMR. Classical strain imaging features of cardiac amyloidosis were only present in 50%. All patients had diffuse, patchy gadolinium enhancement on CMR after PBSCT. Treatment of cardiac amyloidosis with chemotherapy and PBSCT may result in regression of abnormalities on TTE with marked improvement in survival. Post treatment, TTE and CMR structural assessments appear similar. Gadolinium imaging suggests that microscopic residual infiltration persists despite macroscopic regression. Significant cardiac improvements with prolonged survival are seen nonetheless. Multimodality imaging has a vital role in the management of cardiac amyloidosis.

Assessment of speckle tracking strain predictive value for myocardial fibrosis in subjects with Chagas disease

Scipedia content — Fri, 19 May 2017 11:45:42 +0200

One of the most challenging issues of chronic Chagas disease is to provide earlier detection of heart involvement. Two-dimensional speckle tracking (2-D ST) echocardiography, a new imaging modality with useful applications in several cardiac diseases, has been validated for subjects with myocardial infarction against cardiac magnetic resonance (CMR). Here we hypothesize that the longitudinal global strain (LGS) has an incremental value to ejection fraction for predicting myocardial fibrosis in subjects with Chagas disease. This observational study comprised 58 subjects with Chagas disease, confirmed by two positive serologic tests. All subjects underwent conventional Doppler echocardiogram plus speckle tracking strain, and cardiac magnetic resonance. The ROC curve analysis revealed that both LGS (area under the curve: 0.78, p = 0.001) and ejection fraction (area under the curve: 0.82, p

Successful revascularization improves long-term clinical outcome in patients with chronic coronary total occlusion

Scipedia content — Fri, 19 May 2017 11:45:35 +0200

Following the development of breakthrough techniques for percutaneous coronary intervention (PCI) in the treatment of chronic total occlusions (CTO), the initial success rate of PCI in CTO lesions (CTO-PCI) has improved, however, there are few reports regarding the effects of successful CTO revascularization on long-term mortality in Japan. The aim of this study was to compare the long-term clinical outcomes of patients with successful versus failed CTO recanalization and to identify related factors. From all PCI procedures performed in our hospital between 2006 and 2013, CTO-PCIs were extracted and classified into two groups: PCI success (n = 656 patients) and PCI failure (n = 82 patients). Patients with successful procedures only on a second attempt, CTO-PCI in small branches, or CTOs in more than one vessel were excluded. Survival was determined from a telephone interview or the consultation history in the outpatient clinic. Initial angiographic success was achieved in 88.9% of the patients. A Kaplan–Meier plot with log-rank analysis showed that cumulative all-cause death was significantly lower in the success group than in the failure group (p = 0.0003, average follow-up duration in success group vs. failure group was 1531.3 ± 33.5 vs. 1565.3 ± 97.5 days, p = 0.7). Moreover, the rate of evident cardiac death was significantly lower in the success group than in the failure group (3.5% [23/656] vs. 15.9% [13/82], p

Pulmonary vein thromboses might cause and promote cardiovascular disease via genetic modulation by occluding microvessels in elderly patients

Scipedia content — Fri, 19 May 2017 11:45:30 +0200

Implementation of 64-MDCT assesses that short-term warfarin therapy can dissolve a completely occluding small thrombus: A new clue to treat atrial fibrillation

Scipedia content — Fri, 19 May 2017 11:45:25 +0200

Lower pulmonary veins are likely to have a pulmonary vein thrombus

Scipedia content — Fri, 19 May 2017 11:45:21 +0200

Pulmonary vein thrombosis is associated with chest pain in patients without coronary artery stenosis

Scipedia content — Fri, 19 May 2017 11:45:17 +0200

A long and narrow pulmonary vein thrombus attached to the wall of a pulmonary vein

Scipedia content — Fri, 19 May 2017 11:45:13 +0200

Pulmonary vein thrombosis (PVT) is often not diagnosed because PVT has subtle symptoms and PVT is believed to be rare. The mechanism for the formation of PVT is unclear. In this case, I describe a small thrombus in a small branch of a pulmonary vein draining into a larger vein, the right lower pulmonary vein (RLPV). The patient was a 70-year-old male with angina pectoris, and he presented with chest pain. He had no symptoms of cerebral infarction. He previously had been treated with percutaneous coronary intervention and had four stents in the coronary arteries. A 64-slice multidetector computed tomography (64-MDCT) scan was performed to evaluation for in-stent restenosis. A thrombus in the RLPV was shown in axial and sagittal images as a defect in contrast enhancement, representing a small thrombus in a small branch of a pulmonary vein draining into the RLPV. The 64-MDCT scan depicted them well. The effects of PVT are unknown, and more studies are needed.

Nearly all left atrial thrombi may be extended from pulmonary vein thrombi

Scipedia content — Fri, 19 May 2017 11:45:09 +0200

A pulmonary vein thrombus in a patient with autonomic nervous dysfunction

Scipedia content — Fri, 19 May 2017 11:45:05 +0200

Optimum duration of dual antiplatelet treatment could be decided using 64-MDCT: A new hint to treating patients with stents

Scipedia content — Fri, 19 May 2017 11:45:00 +0200

The appearance of a small thrombus in the pulmonary vein indicates the existence of a smaller pulmonary vein

Scipedia content — Fri, 19 May 2017 11:44:55 +0200

Pulmonary vein thrombi in a patient with paroxysmal atrial fibrillation

Scipedia content — Fri, 19 May 2017 11:44:50 +0200

A jumping left atrial thrombus connected to a pulmonary vein thrombus using transthoracic echocardiography and 64-slice multi-detector computed tomography

Scipedia content — Fri, 19 May 2017 11:44:45 +0200

Few studies have reported the differences between transthoracic echocardiography (TTE) and 64-slice multidetector CT (64-MDCT) in identifying left atrium (LA) thrombi. I report the case of a 70 year old man with coronary artery disease and angina who was diagnosed with a thrombus in the left lower pulmonary vein extending to the LA using a non-invasive 64-MDCT scan and TTE. TTE was unable to clearly identify a thrombus in the pulmonary veins, whereas a 64-MDCT scan identified a thrombus in the pulmonary vein but was unable to detect a moving thrombus attached to the mitral valves. The 64-MDCT images of LA thrombi are smaller than those of TTE and the video created using TTE demonstrated a moving thrombus connected to the mitral valve, which was underdiagnosed by a 64-MDCT scan. This case illustrates the complementary role for both TTE and 64-MDCT in the noninvasive diagnosis of left atrial-pulmonary vein thrombi.

A network of pulmonary vein thrombi is a risk factor for ischemic stroke, especially after cardiac surgery: A case report and mini review

Scipedia content — Fri, 19 May 2017 11:44:39 +0200

Stroke remains a devastating complication following cardiac surgery. Pulmonary vein thrombi (PVT) are believed to be rare, but I have reported 37 cases of PVT in elderly patients with chest pain since 2012, indicating that PVT are not unusual. The present case showed that PVT can make a network among four pulmonary veins and left atrium. Currently, PVT are not recognized as a risk factor for ischemic stroke, especially following cardiac surgery. A 76-year-old male was examined by 64-slice multidetector CT (64-MDCT) to assess chest pain. The 64-MDCT scan revealed thrombi in the left upper and lower pulmonary veins, the right upper and lower pulmonary veins and the left atrium (LA) as the defects of contrast enhancements. The LA thrombi seemed to be connected to PVT forming a network of thrombi. To avoid stroke following cardiac surgery, it is important to cope with PVT. How to treat PVT during cardiac surgery should be developed.

Relationship between chronotropic incompetence and β-blockers based on changes in chronotropic response during cardiopulmonary exercise testing

Scipedia content — Fri, 19 May 2017 11:44:33 +0200

Chronotropic incompetence (CI), an attenuated heart rate (HR) response to exercise, is common in patients with cardiovascular disease. The aim of this study was to assess changes in the chronotropic response (CR) during cardiopulmonary exercise testing (CPET) in patients undergoing cardiac rehabilitation and investigate the effects of β-blockers. Patients undergoing cardiac rehabilitation performed CPET. Failure to achieve 80% of the age-predicted maximal HR (APMHR) defined CI. Values of the metabolic chronotropic relationship (MCR) were calculated from the ratio of the HR reserve to metabolic reserve at 4 stages, warm-up (MCR-Wu), anaerobic threshold (MCR-AT), respiratory compensation (MCR-Rc), and peak point (MCR-Pk), using the Wilkoff model. In patients who showed an increase in MCR at ≥ 3 of the 4 exercise stages, CR was considered to have improved. Patients with high BNP levels (≥ 80 pg/ml) had a lower MCR at all stages compared with those with low BNP levels (

Intracoronary administration of nicorandil during primary percutaneous coronary intervention: Impact on restoration of regional myocardial perfusion in reperfused myocardium during the subacute phase of myocardial infarction

Scipedia content — Fri, 19 May 2017 11:44:27 +0200

The impact of nicorandil as adjunctive therapy for percutaneous coronary intervention (PCI) in patients with ST-elevation myocardial infarction (STEMI) is controversial. We performed 15O-labeled water positron emission tomography (PET) to quantify regional myocardial perfusion in patients with STEMI who received nicorandil or no adjunctive therapy during PCI. PCI was performed within 8 h after STEMI onset in 33 patients. 14 patients received intracoronary nicorandil 2 mg immediately after recanalization of the culprit lesion (Nico group). After 3–4 weeks, PET was performed in which myocardial blood flow (MBF) was measured at baseline and during adenosine triphosphate (ATP)-induced hyperemia. Myocardial vascular resistance (MVR) was calculated for all segments. Data were obtained from the reperfused (Rep) and normal segments (Cont) in each patient. In patients not given nicorandil (No-Nico group), the MBF was significantly lower in Rep than that in Cont at baseline and during hyperemia (Cont vs. Rep: 0.82 ± 0.14 vs. 0.68 ± 0.11, P = 0.001, ATP-Cont vs. ATP-Rep: 2.00 ± 0.72 vs. 1.52 ± 0.61, P = 0.017), which was restored in the Nico group (Cont vs. Rep: 0.79 ± 0.17 vs. 0.78 ± 0.20, ATP-Cont vs. ATP-Rep: 2.02 ± 0.84 vs. 1.84 ± 0.62). MVR was elevated in Rep at baseline and during hyperemia in the No-Nico group. MVR elevation in Rep was prevented in the Nico group. 15O-labeled water PET was feasible for segmental analysis of MBF during the subacute phase of STEMI. It revealed that intracoronary administration of nicorandil to STEMI patients who underwent PCI prevented MVR elevation and thus restored MBF in the reperfused segments to a level similar to that in the normal segments.

Sub-aortic obstruction of left ventricular outflow tract secondary to benfluorex-induced endocardial fibrosis

Scipedia content — Fri, 19 May 2017 11:44:20 +0200

Patients exposed to benfluorex have an increased risk of restrictive organic valvular heart disease. Aortic and mitral regurgitations caused by fibrotic valve disease are the most common features observed in exposure to fenfluramine derivatives in general and benfluorex in particular. We report here, for the first time to our knowledge, a well-documented case in which obstructive sub-aortic endocardium fibrosis within the left ventricular outflow tract is related with exposure to a drug that modifies the metabolism of serotonin. It now remains to be established whether extensive fibrosis of the myocardium in addition to well-documented valvular fibrosis may develop in patients exposed to amphetamine-derived drugs affecting the serotonin system.

Myocardial ischemic preconditioning in a porcine model leads to rapid changes in cardiac extracellular vesicle messenger RNA content

Scipedia content — Fri, 19 May 2017 11:44:14 +0200

Extracellular vesicles (EVs) are thought to exert protective effects after ischemic and remote ischemic preconditioning. It is not well understood which EV content factors are most relevant for protective effects. We hypothesize that ischemic preconditioning leads to qualitative changes in EV mRNA content and quantitative changes in EV size and number. Using an in vivo porcine ischemic preconditioning model, EVs were collected from coronary venous blood, and isolated by differential ultracentrifugations. The presence and purity of EV were verified by electron microscopy and Western blot, and EV number was assessed by nanoparticle tracking analysis. The mRNA EV was identified by microarray. Gene ontology analysis showed enrichment of EV mRNA coding for proteins associated with regulation of transcription, translation, extracellular matrix, morphogenic development and feeding behavior. There were 11, 678 different mRNA transcripts detected in EV, where a total of 1103 was significantly increased or decreased after preconditioning, of which 638 mRNA sequences were up-regulated and/or emerged due to preconditioning. Several of them have known association with ischemic preconditioning. There was no significant difference in EV quantity or size before and after preconditioning. These findings demonstrate in an in vivo model that myocardial ischemic preconditioning influences the composition of mRNA in EV, including gene transcripts for proteins associated with the protective effect of ischemic preconditioning. The finding that preconditioned parental cells release EV containing mRNA that is qualitatively different from those released by non-preconditioned cells shows the importance of the external milieu on parental cell EV production.

An inspection of therapeutic hypothermia preceding coronary reperfusion in patients with a cardiogenic shock complicating anterior ST-segment elevation myocardial infarction

Scipedia content — Fri, 19 May 2017 11:44:08 +0200

We retrospectively investigated our hypothesis that pre-percutaneous coronary intervention (PCI) procedural therapeutic hypothermia may have clinical advantages in patients with a profound cardiogenic shock complicating anterior ST-segment elevation myocardial infarction (STEMI). Of 483 consecutive patients treated with PCI for a first anterior STEMI including 31 patients with aborted sudden cardiac arrest between 2009 and 2013, a total of 37 consecutive patients with an anterior STEMI complicated with profound cardiogenic shock defined as the presence of hyperlactic acidemia (serum levels of lactate > 4 mmol/L) with mechanical circulatory support were identified. An impaired myocardial tissue-level reperfusion (angiographic myocardial blush grade 0 or 1) and in-hospital mortality were evaluated in accordance with the presence or absence of pre-PCI procedural therapeutic hypothermia. Thirteen patients were treated with pre-PCI procedural therapeutic hypothermia and 24 were not inducted with therapeutic hypothermia. Five patients with and 18 without pre-PCI procedural therapeutic hypothermia impaired myocardial tissue-level reperfusion (38% vs. 75%, p = 0.037). A total of 26 patients with in-hospital death (overall in-hospital mortality 70%) were composed of 6 with and 20 without therapeutic hypothermia (in-hospital mortality 46% vs. 83%, p = 0.028). A multivariate analysis demonstrated a significant association of pre-PCI procedural therapeutic hypothermia (p = 0.021) with in-hospital survival benefit. Adverse events associated with therapeutic hypothermia were not found in 12 patients who completed this treatment. The present study may imply a crucial possibility of clinical benefits of pre-PCI procedural therapeutic hypothermia in patients with a cardiogenic shock complicating anterior STEMI.

Circulating level of microRNA-126 may be a potential biomarker for recovery from smoking-related vascular damage in middle-aged habitual smokers

Scipedia content — Fri, 19 May 2017 11:44:02 +0200

Cigarette smoking promotes vascular endothelial damage and accelerates progression of atherosclerosis. The purpose of this study was to examine whether the circulating level of vascular endothelium-enriched microRNA-126 (miR-126), which is highlighted as a regulator of gene expression, would serve as a novel biomarker for recovery from smoking-related vascular damage. Middle-aged male smokers (n = 30) were enrolled and instructed to stop smoking. Their clinical profiles and laboratory findings including expression of miR-126 were investigated before and after 8 weeks of smoking cessation. Serum levels of cotinine, metabolites of nicotine, were measured to confirm smoking cessation. Endothelial function for peripheral small vessels was assessed and expressed as reactive hyperemia peripheral arterial tonometry (RH-PAT) index. The expression of miR-126 in plasma was analyzed by quantitative real-time PCR. At baseline, serum cotinine levels were inversely correlated with RH-PAT index (r = − 0.48, P

More haste, less speed: Cardiac perforation by a thoracentesis catheter

Scipedia content — Fri, 19 May 2017 11:43:56 +0200

Association of estimated central blood pressure measured non-invasively with pulse wave velocity in patients with coronary artery disease

Scipedia content — Fri, 19 May 2017 11:43:51 +0200

Usefulness of excimer laser atherectomy for balloon uncrossable lesion in chronic total occlusion

Scipedia content — Fri, 19 May 2017 11:43:45 +0200

QRS complex maximum deflection index in aortic cusp premature ventricular complexes

Scipedia content — Fri, 19 May 2017 11:43:40 +0200

Prognostic value of positron emission tomography myocardial perfusion imaging beyond traditional cardiovascular risk factors: Systematic review and meta-analysis

Scipedia content — Fri, 19 May 2017 11:43:34 +0200

Despite substantive growth in utilization of positron emission tomography (PET) myocardial perfusion imaging (MPI), evidence on its prognostic value is limited. We aimed to comprehensively evaluate the prognostic literature of PET perfusion measures according to the most recent American Heart Association recommendations for assessment of novel cardiovascular biomarkers. We searched the literature for studies reporting associations of PET MPI measures and outcomes in patients with known or suspected coronary artery disease. We documented hazard ratios (HR) and 95% confidence intervals (CI) of association effects and quantitatively synthesized them with random-effects meta-analyses. Discrimination, calibration and risk reclassification after addition of PET MPI measures to standard prognostic models were documented. We identified 20 eligible studies with median n = 551 patients. In meta-analyses, the extents of ischemic and scarred myocardium were significantly associated with cardiac death. Meta-analyses of multivariate estimates for abnormal summed stress score ≥ 4 and myocardial perfusion reserve

Usefulness of routine aortic valve calcium score measurement for risk stratification of aortic stenosis and coronary artery disease in patients scheduled cardiac multislice computed tomography

Scipedia content — Fri, 19 May 2017 11:43:28 +0200

This study sought to investigate the clinical utility of aortic valve calcium score (AVCS) determined by using cardiac multislice computed tomography (MSCT). Data of 1315 consecutive patients who underwent both conventional echocardiography and MSCT were reviewed. Degree of aortic stenosis (AS) was assessed according to mean pressure gradient (mPG) measured by echocardiography. Extent of coronary artery disease (CAD) derived by MSCT also was evaluated in 1173 patients who did not undergo prior coronary treatment. Both AVCS and coronary calcium score (CCS) were defined by Agatston units (AU) according to MSCT findings. A total of 613 of 1315 patients were defined as AVCS positive (mean, 100 AU [range, 31.0–380.0 AU]). AVCS showed significant correlations with mPG (Spearmans ρ = 0.81, p

Transcatheter aortic valve implantation in patients with pre-existing chronic kidney disease

Scipedia content — Fri, 19 May 2017 11:43:21 +0200

We investigated the effect of chronic kidney disease (CKD) on morbidity and mortality following transcatheter aortic valve implantation (TAVI) including patients on haemodialysis, often excluded from randomised trials. We performed a retrospective post hoc analysis of all patients undergoing TAVI at our centre between 2008 and 2012. 118 consecutive patients underwent TAVI, 63 were considered as having (CKD) and 55 not having (No-CKD) significant pre-existing CKD, (defined as estimated glomerular filtration rate (eGFR)

Fractional flow reserve in acute coronary syndromes: A review

Scipedia content — Fri, 19 May 2017 11:43:16 +0200

Fractional flow reserve (FFR) assessment provides anatomical and physiological information that is often used to tailor treatment strategies in coronary artery disease. Whilst robust data validates FFR use in stable ischaemic heart disease, its use in acute coronary syndromes (ACS) is less well investigated. We critically review the current data surrounding FFR use across the spectrum of ACS including culprit and non-culprit artery analysis. With adenosine being conventionally used to induce maximal hyperaemia during FFR assessment, co-existent clinical conditions may preclude its use during acute myocardial infarction. Therefore, we include a current review of instantaneous wave free ratio as a novel vasodilator independent method of assessing lesion severity as an alternative strategy to guide revascularisation in ACS.

Screening for asymptomatic coronary heart disease in the young ‘at risk’ population: Who and how?

Scipedia content — Fri, 19 May 2017 11:43:11 +0200

Deaths due to coronary heart disease (CHD) remain high worldwide, despite recent achievements. An effective screening strategy may improve outcomes further if implemented in a high or ‘at risk’ cohort. Asymptomatic CHD in the young maybe underappreciated and applying an effective screening strategy to a young cohort may lead to improved outcomes due to significant socioeconomic impact from the consequences of CHD in this sub-group. A positive family history of CHD, which is known to be associated with an increased risk of future myocardial events, could aid in identifying the ‘at risk’ young cohort. Traditional cardiovascular risk scoring systems are in wide use but lack the sensitivity or specificity required to estimate risk in an individual. Rather their use is limited to predicting population attributable risk. Functional studies such as exercise stress tests are readily available and cost effective but do not have the required sensitivity required to suggest their use as part of a screening protocol. Coronary CT angiography has been demonstrated to have high sensitivity for the detection of CHD and therefore may be suitable for screening purposes but there are concerns regarding radiation exposure. Here we review the evidence for the use of potential screening strategies and the suitability of using such strategies to estimate risk of CHD in a young ‘at risk’ population.

Femoral arterial closure using ProGlide® is more efficacious and cost-effective when ambulating early following cardiac catheterization

Scipedia content — Fri, 19 May 2017 11:43:06 +0200

This was a prospective, single-center study evaluating the efficacy and cost-effectiveness of early ambulation (within 30 min) following femoral artery closure with the ProGlide® suture-mediated vascular closure device (PD) in patients undergoing diagnostic cardiac catheterization compared with manual compression. It is unclear whether early ambulation with ProGlide is safe or is associated with patient satisfaction and cost savings as compared with manual compression (MC). Inclusion criteria were met in 170 patients (85 PD and 85 MC patients). Patients ambulated 20 ft. within 30 min (PD) or after the requisite 4 h recumbent time (MC) if feasible. Primary endpoint was time-to-ambulation (TTA) following device closure. We also directly compared the safety of closure, times-to-hemostasis (TTH), -ambulation (TTA) and -discharge (TTD) with MC and, using a fully allocated cost model, performed cost analysis for both strategies. Multivariate analysis was used to determine predictors of patient satisfaction. The primary endpoint of safe, early ambulation was achieved following closure (mean of 27.1 ± 14.9 min, 95% confidence interval [CI] 25.2–30.2). Predictors of patient satisfaction in the PD group were absence of pain during closure, decreased TTA, and drastic reductions in TTD, the latter contributed indirectly to significant cost savings in the PD group (1250.3 ± 146.4 vs. 2248.1 ± 910.2 dollars, respectively, P

Coronary plaque morphology on multi-modality imagining and periprocedural myocardial infarction after percutaneous coronary intervention

Scipedia content — Fri, 19 May 2017 11:42:58 +0200

Percutaneous coronary intervention (PCI) may be complicated by periprocedural myocardial infarction (PMI) as manifested by elevated cardiac biomarkers such as creatine kinase (CK)-MB or troponin T. The occurrence of PMI has been shown to be associated with worse short- and long-term clinical outcome. However, recent studies suggest that PMI defined by biomarker levels alone is a marker of atherosclerosis burden and procedural complexity but in most cases does not have independent prognostic significance. Diagnostic multi-modality imaging such as intravascular ultrasound, optical coherence tomography, coronary angioscopy, near-infrared spectroscopy, multidetector computed tomography, and magnetic resonance imaging can be used to closely investigate the atherosclerotic lesion in order to detect morphological markers of unstable and vulnerable plaques in the patients undergoing PCI. With the improvement of technical aspects of multimodality coronary imaging, clinical practice and research are increasingly shifting toward defining the clinical implication of plaque morphology and patients outcomes. There were numerous published data regarding the relationship between pre-PCI lesion subsets on multi-modality imaging and post-PCI biomarker levels. In this review, we discuss the relationship between coronary plaque morphology estimated by invasive or noninvasive coronary imaging and the occurrence of PMI. Furthermore, this review underlies that the value of the multimodality coronary imaging approach will become the gold standard for invasive or noninvasive prediction of PMI in clinical practice.

The ascending aortic aneurysm: When to intervene?

Scipedia content — Fri, 19 May 2017 11:42:52 +0200

Thoracic ascending aorta aneurysms (TAA) are an important cause of mortality in adults but are a relatively less studied subject compared to abdominal aortic aneurysms (AAA). The purpose of this review is to explain the main aspects (etiology, pathophysiology, diagnosis) of this disease and to summarize the most recent developments in its management. Literature was obtained through online health related search engines (PubMed, MEDLINE) by including the following keywords: ascending aorta aneurysm, thoracic aneurysms, Marfan syndrome, bicuspid aortic valve, familial thoracic syndrome, aortic dissection, aorta imaging and aortic aneurysm guidelines. We included articles dating from 1980 to 2014. Literature revealed how lethal this disease can be and how simple steps such as follow-up and prophylactic surgery can significantly reduce morbidity and mortality. This review also allowed us to realize the many developments that have been made in recent years in the understanding of pathologic mechanisms of this disease. TAA is a silent disease that needs to be recognized early in its course and followed closely in order to recommend appropriate preventive and prophylactic therapy in a timely manner.

Safety and feasibility of transcatheter renal sympathetic denervation using different types of catheter and various radiofrequency settings

Scipedia content — Fri, 19 May 2017 11:42:45 +0200

To evaluate in vivo the feasibility and safety of renal sympathetic denervation (RSD) with different catheters and various radiofrequency protocols. Twenty-two pigs were included. First 2 pigs were enrolled in a feasibility protocol using one catheter and power from 5 W to 20 W. The next 10 pigs underwent RSD with three different catheters and four different RF-power settings of 5 W, 8 W, 10 W and 12 W in one minute per lesion (Protocol 1). The following 10 (Pigs 13 to 22) underwent RSD with five types of catheters (including the Symplicity® catheter), powers of 8 W and 10 W and two minutes RF-application (Protocol 2). Angiographic data were obtained at baseline, during and after RSD. At last, renal arteries were excised and analyzed macroscopically. The first pig developed severe renal stenoses with lesions of 15 to 20 W correlated with macroscopic alterations. The second feasibility pig did not develop renal stenosis with 5 and 8 W. In Protocol 1 from 60 RF-lesions, we observed 7 stenoses (≥ 30%). Three were severe (one of 80% with 10 W and two of 80% with 12 W). In Protocol 2 from 57 lesions we observed only 1 stenosis of 50% with 8 W with Symplicity® catheter. Severe stenosis was not observed. In this study, renal sympathetic denervation showed safety using five types of catheters when applying RF-energy less than 10 W, within main stems of arteries larger than 3.0 mm diameter and a distance between lesions of at least 1 time catheter tip length.

Using MRI to predict future adverse cardiac remodelling in a male mouse model of myocardial infarction

Scipedia content — Fri, 19 May 2017 11:42:37 +0200

Mice are frequently used in research to examine outcomes of myocardial infarction (MI) and to investigate therapeutic interventions at an early pre-clinical stage. The MI model is generated by surgically occluding a major coronary artery, but natural variation in murine coronary anatomy can generate variable outcomes that will inevitably affect the accuracy of such investigations. The aim of this study was to use MRI to derive the most sensitive early variable that could be used to predict subsequent adverse cardiac remodelling in a male mouse model of MI. Using a longitudinal study design, heart structure and function were evaluated using cardiac MRI at one week following surgical MI to generate the early measurements and again at four weeks, when the scar had matured. The primary variables measured at week one were left ventricular volumes at end systole (LV-ESV) and at end diastole (LV-EDV), infarct size, LV-cardiac mass, and ejection fraction (EF). Univariate and multiple regression analyses showed that LV-ESV at one week following MI could be used to accurately predict various parameters of adverse LV remodelling at four weeks post-MI. However, the highest correlation was between LV-ESV at one week following MI and LV-EDV at four weeks (r = 0.99, p

A predictive model to identify patients with suspected acute coronary syndromes at high risk of cardiac arrest or in-hospital mortality: An IMMEDIATE Trial sub-study

Scipedia content — Fri, 19 May 2017 11:42:31 +0200

The IMMEDIATE Trial of emergency medical service use of intravenous glucose–insulin–potassium (GIK) very early in acute coronary syndromes (ACS) showed benefit for the composite outcome of cardiac arrest or in-hospital mortality. This analysis of IMMEDIATE Trial data sought to develop a predictive model to help clinicians identify patients at highest risk for this outcome and most likely to benefit from GIK. Multivariable logistic regression was used to develop a predictive model for the composite endpoint cardiac arrest or in-hospital mortality using the 460 participants in the placebo arm of the IMMEDIATE Trial. The final model had four variables: advanced age, low systolic blood pressure, ST elevation in the presenting electrocardiogram, and duration of time since ischemic symptom onset. Predictive performance was good, with a C statistic of 0.75, as was its calibration. Stratifying patients into three risk categories based on the models predictions, there was an absolute risk reduction of 8.6% with GIK in the high-risk tertile, corresponding to 12 patients needed to treat to prevent one bad outcome. The corresponding values for the low-risk tertile were 0.8% and 125, respectively. The multivariable predictive model developed identified patients with very early ACS at high risk of cardiac arrest or death. Using this model could assist treating those with greatest potential benefit from GIK.

Cardiac calcified amorphous tumor: A systematic review of the literature

Scipedia content — Fri, 19 May 2017 11:42:25 +0200

Calcified amorphous tumor (CAT) of the heart is a rare non-neoplastic intracavitary cardiac mass. Several case reports have been published but large series are lacking. To determine clinical features, current management and outcomes of this rare disease. A systematic review of all articles reporting cases of CAT in order to perform a pooled analysis of its clinical features, management and outcomes. An electronic search of all English articles using PUBMED was performed. Further studies were identified by cross-referencing from relevant papers. We restricted inclusion to articles reporting cases of CAT in the English language literature published up to July 2014. One author performed data extraction using predefined data fields. A total of 27 articles, reporting 42 cases of CAT were found and included in this review. In this review, the most frequent presenting symptoms were dyspnea and embolic events. Mitral valve and annulus were the most frequent location of CAT. Surgery was most of the time required to confirm diagnosis, and was relatively safe. Overall outcome after surgical resection was good.

Anatomical and hemodynamic evaluations of the heart and pulmonary arterial pressure in healthy children residing at high altitude in China

Scipedia content — Fri, 19 May 2017 11:42:19 +0200

Altitude-hypoxia induces pulmonary arterial hypertension and altered cardiac morphology and function, which is little known in healthy children at high altitude. We compared the cardiopulmonary measurements between the healthy children at 16 m and those at 3700 m in China and between the Hans and the Tibetans at 3700 m. Echocardiography was assessed in 477 children (15 day–14 years) including 220 at 16 m and 257 at 3700 m. The dimensions and wall thickness of the left- and right-sided heart, systolic and diastolic functions including cardiac output index (CI) were measured using standard methods. Mean pulmonary arterial pressure (mPAP) was estimated by the Doppler waveforms in the main pulmonary artery. Compared to the 16 m-group, 3700 m-group had higher mPAP, increasing dilatation of the right heart, and slower decrease in right ventricular hypertrophy in 14 years (p 0.20). Systolic and diastolic functions of both ventricles were significantly reduced, but CI was higher (p 0.05). Children living at high altitude in China have significantly higher mPAP, dilated right heart and slower regression of right ventricular hypertrophy in the first 14 years of life. Systolic and diastolic functions of both ventricles were reduced with a paradoxically higher CI. There was no significant difference in these features between the Hans and the Tibetans. These values provide references for the care of healthy children and the sick ones with cardiopulmonary diseases at high altitude.

Catheter-based intervention for pulmonary vein stenosis due to fibrosing mediastinitis: The Mayo Clinic experience

Scipedia content — Fri, 19 May 2017 11:42:12 +0200

Fibrosing mediastinitis (FM) is a rare but fatal disease characterized by an excessive fibrotic reaction in the mediastinum, which can lead to life-threatening stenosis of the pulmonary veins (PV). Catheter-based intervention is currently the only viable option for therapy. However, the current literature on how best to manage these difficult cases, especially in regards to sequential interventions and their potential complications is very limited. We searched through a database of all patients who have undergone PV interventions at the Earl H. Wood Cardiac Catheterization Laboratory in Mayo Clinic, Rochester. From this collection, we selected patients that underwent PV intervention to relieve stenosis secondary to FM. Eight patients were identified, with a mean age of 41 years (24–59 years). Five were men, and three were women. Three patients underwent balloon angioplasty alone, and five patients had stents placed. The majority of patients had acute hemodynamic and symptomatic improvement. More than one intervention was required in five patients, four patients had at least one episode of restenosis, and four patients died within four weeks of their first PV intervention. We describe the largest reported case series of catheter-based intervention for PV stenosis in FM. Although catheter-based therapy improved hemodynamics, short-term vascular patency, and patient symptoms, the rate of life-threatening complications, restenosis, and mortality associated with these interventions was found to be high. Despite these associated risks, catheter-based intervention is the only palliative option available to improve quality of life in severely symptomatic patients with PV stenosis and FM. Patients with PV stenosis and FM (especially those with bilateral disease) have an overall poor prognosis in spite of undergoing these interventions due to the progressive and recalcitrant nature of the disease. This underscores the need for further innovative approaches to manage this disease.

Intima-media thickness of the descending aorta in patients with bicuspid aortic valve

Scipedia content — Fri, 19 May 2017 11:42:07 +0200

A bicuspid aortic valve (BAV) is associated with accelerated aortic valve disease (AVD) and abnormalities in aortic elasticity. We investigated the intima-media thickness of the descending aorta (AoIMT) in patients with AVD with or without an ascending aortic aneurysm (AscAA), in relation to BAV versus tricuspid aortic valve (TAV) phenotype, type of valve disease, cardiovascular risk factors, and single-nucleotide polymorphisms (SNPs) with a known association with carotid IMT. 368 patients (210 with BAV, 158 with TAV, ), mean age 64 ± 13 years) were examined using transesophageal echocardiography (TEE) before valvular and/or aortic surgery. No patient had a coronary disease (CAD). The AoIMT was measured on short-axis TEE images of the descending aorta using a semi-automated edge-detection technique. AoIMT was univariately (P

Coronary calcification with no flow limiting lesions: A potential cause for ischaemic dysfunction in syndrome X patients

Scipedia content — Fri, 19 May 2017 11:42:00 +0200

Exertional angina in patients with no coronary flow limiting lesions remains a clinical puzzle. We aimed to assess the extent of coronary artery calcification (CAC) and its relationship to ventricular wall motion function using stress echocardiography in a group of patients limited by exertional angina, but no obstructive lesions. We compared CT coronary calcium score (CACS) and dobutamine stress echocardiography in 55 patients (age 64.7 ± 7.7 years), divided into Group 1 (CACS ≤ 100) and Group 2 (CACS > 100). No patient had LV ejection fraction-EF

Left ventricular diastolic gradient in hypertrophic cardiomyopathy

Scipedia content — Fri, 19 May 2017 11:41:54 +0200