Correlation between coronary angioscopy yellow grade and lipid plaque assessment by integrated backscatter intravascular ultrasound

Coronary angioscopy (CAS) enables direct qualitative assessment of the coronary artery lumen, while integrated backscatter intravascular ultrasound (IB-IVUS) provides a quantitative evaluation of coronary plaque tissue characteristics. Despite the utility of both techniques in assessing coronary plaque status, data on the correlation between their findings remain limited. To investigate the association between CAS-derived findings and results obtained through IB-IVUS. This retrospective analysis included 36 patients who underwent both CAS and IB-IVUS during percutaneous coronary intervention (PCI) at our institution. CAS and IB-IVUS were performed on the same coronary artery treated during PCI. Plaques were categorized into four groups based on their yellow color grade using CAS. For the IB-IVUS analysis, measurements were performed at the minimum lumen diameter site of the culprit lesion. A significant correlation was observed between plaque yellowishness and plaque characteristics on IB-IVUS. Higher plaque yellowishness was associated with an increased percentage of all lipid pool (P < 0.01), a greater proportion of attenuated plaque (P < 0.01), and a larger estimated lipid plaque volume (P < 0.01). Additionally, plaques with higher yellowishness grades had significantly thinner fibrous caps (P < 0.01). The findings suggest that higher plaque yellowishness observed via CAS correlates with a larger lipid plaque volume and thinner fibrous caps, as assessed through IB-IVUS.