Scipedia: Collection of Heart & Vasculature

¿Cómo el diagnóstico temprano de la insuficiencia valvular cardiaca puede prevenir una cirugía mayor?

Emilio Guzmán — Thu, 03 Jun 2021 19:43:02 +0200

Explicando a fondo las diferentes enfermedades valvulares, su diagnóstico, tratamiento y cómo podemos prevenirlas. Efectos y riesgos de someterse a una cirugía.

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