Abstract 5451: Coronary Spatial Distribution of Non-ST Elevation Myocardial Infarction is Non-Uniform and Clustered in the Proximal Portion of the Coronary Tree
Introduction: We hypothesized that plaque rupture leading to NSTEMI is a non-uniform process with variable risk for different anatomic locations within each coronary artery. It is not known whether this distribution is similar to that in STEMI, where we have previously observed proximal clustering of lesions.
Methods: We used quantitative angiographic analysis (QCA) to compare the spatial location of lesions in NSTEMI to STEMI in consecutive patients undergoing coronary angiography at the Brigham and Women’s Hospital over a 24-month period for NSTEMI and STEMI (N= 200 and 208 respectively). The segment lengths of the culprit vessel and its side branches were measured. The Wilcoxon rank sum test was used to compare the distribution of culprit lesions in NSTEMI vs. STEMI.
Results: NSTEMI patients were older and had a higher prevalence of prior infarction, diabetes mellitus, hypertension, dyslipidemia, and renal insufficiency. Despite these differences, lesions in both NSTEMI and STEMI were clustered in the proximal third of each of the coronary arteries. There was no significant difference in the spatial distribution of the lesions in NSTEMI as compared to STEMI in the LAD, p=0.36 (Fig 1a & b⇓), LCx, p=0.13 or RCA, p=0.22.)
Conclusion: We conclude that NSTEMI plaque ruptures are not uniformly distributed but proximally clustered similar to STEMI lesions. This suggests that the anatomic zones at risk for acute thrombosis are independent of the type of acute coronary syndrome and that the proximal segments are at highest risk.