Abstract

In optical coherence tomography (OCT)-guided percutaneous coronary intervention (PCI), stent size is usually determined according to the pre-PCI lumen size of either the distal or proximal reference site. However, the effect of the OCT imaging catheter crossing the target lesion on the reference lumen measurements has not been studied. We evaluated changes in the reference lumen size before and after PCI using frequency domain OCT. For 100 consecutive patients with PCI, mean lumen diameter (LD) and lumen area (LA) were measured at the proximal and distal reference sites before and after coronary stent implantation with OCT. Mean LD and LA of the distal reference site were significantly increased after PCI with stent implantation (2.57 ± 0.6 to 2.62 ± 0.64 mm, p < 0.01 and 5.20 ± 2.66 to 5.41 ± 2.54 mm2, p < 0.01, respectively). By contrast, these indices at the proximal reference site were significantly decreased. ROC curve analysis selected MLA of 1.50 mm2 as the best cutoff value for changes in mean LD. Distal mean LD was markedly increased after PCI in lesions with MLA < 1.50 mm (2.28 ± 0.48 to 2.40 ± 0.17 mm, P < 0.001), but did not change in lesions with MLA > 1.50 mm2. Tissue characteristics were not correlated with changes in reference lumen size. When we select the stent size during OCT-guided PCI, we need to pay attention to the decrease in the luminal measurement of the reference sites, especially in lesions with tight stenosis.

Abstract

There is limited data on how well 2D-QCA and OCT agree with each other for measurement of coronary artery lumen dimensions. We aimed to assess the agreement between the two modalities. Patients undergoing OCT for assessment of coronary artery lesions were reviewed. Minimum luminal diameter (MLD), proximal reference diameter and distal reference diameter were measured for each lesion prior to stenting. OCT was performed in 64 patients and 40 lesions were suitable for analysis. There was a good correlation for proximal and distal reference diameters (r = 0.86, p < 0.0001 and r = 0.92, p < 0.0001 respectively). There was good agreement on Bland–Altman analysis, the proximal and distal reference diameters measured by QCA were on average 0.09 mm (95% CI, − 0.52 to 0.53 mm) and 0.1 mm (95% CI, − 0.59 to 0.6 mm) smaller than OCT respectively. There was a satisfactory correlation (r = 0.63, p = < 0.0001) between QCA and OCT for MLD. However, the MLD by QCA was 0.49 mm (95% CI, − 1.57 to 0.59 mm) smaller than OCT, suggesting a poor agreement for MLD. There is a good correlation and agreement between QCA and OCT for measurement of proximal and distal reference diameters. However, the MLD was underestimated by QCA.