Impact of coronary plaque burden and composition on periprocedural myocardial infarction and coronary flow reserve after percutaneous coronary intervention

Periprocedural myocardial infarction (PMI) is one of the major complications of percutaneous coronary intervention (PCI). We investigated the influence of coronary plaque burden and characteristics on PMI using intravascular ultrasound (IVUS) with radiofrequency-based tissue characterization technology (iMAP). The study population consisted of 33 consecutive patients with stable angina pectoris who underwent PCI. IVUS images were recorded before and after PCI for offline analysis, and coronary flow reserve (CFR) was measured after PCI. PMI was defined as a post-PCI cardiac troponin T elevation > 5 × 99^th percentile of the upper reference limit (0.014 ng/mL). Plaque volume in patients with PMI (n = 12) was significantly greater than that in patients without PMI (n = 21) (240.4 ± 106.0 mm3 versus 152.1 ± 76.9 mm³, P = 0.0096). The iMAP-IVUS analysis demonstrated that the fibrotic, lipidic, and necrotic tissue volume within culprit lesions were also greater in patients with PMI than in patients without PMI (129.4 ± 52.2 mm³ versus 94.6 ± 40.8 mm³, P = 0.041; 26.8 ± 10.5 mm³ versus 15.8 ± 11.5 mm³, P = 0.011; and 81.3 ± 48.4 mm³ versus 40.2 ± 33.6 mm³, P = 0.0071, respectively). Multivariate logistic analysis demonstrated that necrotic tissue volume was the only independent predictor of PMI. Multiple regression analysis demonstrated that the post-PCI CFR values signifi cantly correlated with percent plaque burden, and there were no correlations with the percent tissue burden of each plaque component. In conclusion, the iMAP-IVUS analyses demonstrate that necrotic tissue volume is a potent predictor of PMI. Microcirculatory disturbance after PCI is significantly influenced by percent plaque burden, regardless of plaque compositions.