Objectives: Analysis of conventional angiograms has suggested that specific anatomic parameters of particular segments of a coronary artery render them prone to vulnerable plaque development, plaque rupture, and consequent thrombosis. This study aimed at performing a three-dimensional analysis of recanalized left anterior descending (LAD) coronary arteries in patients who had suffered an anterior ST-elevation myocardial infarction (STEMI).
Methods: Coronary angiograms of 76 consecutive patients with an anterior STEMI and a recanalized LAD were reconstructed in the three-dimensional space, and compared with angiograms of 76 patients with stable coronary artery disease (SCAD) and significant LAD stenosis.
Results: In both groups the majority of lesions occurred between 20 and 40 mm (P=0.745), but the number of lesions beyond 60 mm from the ostium was significantly higher in SCAD compared with STEMI (P=0.045). Culprit lesions were statistically significantly longer in patients with STEMI compared with SCAD (18.3+/-7.5 vs. 12.7+/-6.2 mm, P<0.001). Cut-off point analysis indicated a lesion length of >or=12.5 mm as discriminating threshold between SCAD and STEMI (sensitivity 79% and specificity 63%). Bifurcation branches on the culprit lesion were seen in 79% of the patients with STEMI and 58% of those with SCAD (P=0.026). Lesion angulation was significantly sharper in STEMI compared with SCAD patients in diastole (155+/-15 vs. 160+/-14 degrees, P=0.037). Multiple logistic regression model including these parameters had a high discriminating ability with c-statistic 0.78 (95% confidence intervals: 0.71-0.86), sensitivity 72.4%, and specificity 75%.
Conclusion: Specific anatomic characteristics of LAD segments predispose to development of plaque rupture and thrombosis.