IVUS-VH relation to the extent and composition of atherosclerotic plaque and clinical outcome prognosis

Background and aim: Most frequent and generally unpredictable coronary plaque rupture impacts the burden of coronary artery disease but features or signs related to plaque remodeling into the high risk structure are not clearly detectable by using ordinary visualization methods. Till yet there are no evident criteria for additional using IVUS. The aim of the study was to determinate intravascular ultrasound virtual histology (IVUS-VH) importance in identifying high risk plaques, which can contribute to increased rupture hazard. Methods: We selected 30 patients with stabile angina pectoris. 50 plaques were analyzed with coronary angiography digital assessment tool and IVUS similarly. Differences of stenoses measured by both methods, then were calculated and compared to composition of plaques evaluated by IVUS-VH. Results: Plaques were mostly formed of fibrous tissue (FI) (2.6 mm2; 57.89 %). Necrosis was found to make in average one-fifth of analyzed plaques (0.75 mm2, 19.60 %). Calcification made up the smallest part of plaques (0.3 mm2, 8.58 %). Plaques with higher necrosis component appeared to be significantly greater in IVUS compared to coronary angiography. In group A necrosis made up 1.40±1.05 mm2; group B – 0.87±0.52 mm2, and group C – 0.62 ±0.45 mm2 (p= 0.020). The same tendency was observed with FI: group A – 3.38±3.20 mm2; group B – 2.90±2.6 mm2 and group C – 2.04±165 mm2 (p= 0.082). Correlation analysis revealed negative moderate relationship between groups and necrosis percentage (r= –0.40, p= 0.004), and FI (r= –0.29, p= 0.039) components of the plaques. Conclusion: IVUS-VH provides new insight into the evaluation of different composition of plaques. However, despite the advantages, IVUS-VH remains costly and not always technically adaptive procedure, so it is necessary to pursue for new methods or technologies to identify atherosclerotic plaques at risk