Abstract 1802: Anatomic Distribution of Culprit Lesions in Patients with Non-ST-Segment Elevation Myocardial Infarction Undergoing Percutaneous Coronary Intervention
Background Studies of ST-segment elevation myocardial infarction have shown culprit lesions to predominantly involve the left anterior descending (LAD) and right coronary (RCA) arteries. The anatomic distribution and angiographic characteristics of culprit lesions in non-ST-segment elevation myocardial infarction (NSTEMI) are less well-described.
Methods Data on NSTEMI patients undergoing percutaneous coronary intervention (PCI) in the ACC National Cardiovascular Data Registry (2004–2006) were analyzed to determine the anatomic distribution of culprit lesions, the incidence of occluded culprit vessels at time of angiography, patient characteristics and outcomes. In patients with multivessel PCI, culprit lesion was defined as the first attempted lesion.
Results Among 30,385 NSTEMI patients who met the inclusion criteria, the culprit lesion was located in the LAD in 11,609 patients (38%), in the circumflex (LCx) in 8,358 (28%), and in the RCA in 10,418 (34%). A total of 10,259 (34%) patients had an occluded infarct artery at the time of angiography, with 69% of these occlusive lesions in the RCA or LCx. Patients with occluded infarct vessels were younger with fewer comorbidities. Occlusive lesions were associated with higher fluoroscopy times and contrast volumes, and resulted in lower lesion success rates and higher in-hospital mortality (Table⇓). A culprit LAD lesion was associated with the highest risk of in-hospital mortality and heart failure in both occluded and non-occluded subgroups.
Conclusions An occluded infarct artery occurs in over 1/3 of patients with NSTEMI and is associated with worse outcomes. Occlusive lesions more frequently involve the posterior circulation which may favor presentation as NSTEMI due to lack of diagnostic electrocardiographic findings. Further methods of risk stratification are needed to identify these NSTEMI patients for whom the risk of adverse outcomes may be reduced with early angiography and revascularization.