Incidence and impact of totally occluded culprit coronary arteries in patients presenting with non-ST-segment elevation myocardial infarction.

The accuracy of the 12-lead electrocardiogram in detecting coronary artery occlusion is limited. We sought to determine the incidence, distribution, and outcomes of patients who have total occlusion of the culprit artery but present with non-ST-segment elevation myocardial infarction (NSTEMI). The randomized Acute Catheterization and Urgent Intervention Triage Strategy trial enrolled 13,819 patients presenting with non-ST-segment elevation acute coronary syndromes who underwent an early invasive strategy. The present study includes 1,319 patients with baseline biomarker elevation (NSTEMI) and no history of coronary artery bypass graft who underwent percutaneous coronary intervention of a single culprit vessel. We compared the baseline characteristics and outcomes according to whether the culprit vessel was occluded (baseline Thrombolysis In Myocardial Infarction [TIMI] 0 to 1) or patent (TIMI 2 to 3 flow) by angiographic core laboratory assessment. TIMI 0 to 1 flow in the culprit artery was present in 262 of 1,319 (19.9%) patients. The incidence of coronary occlusion was 28.4%, 19.3%, and 12.6% in patients with NSTEMI because of right coronary, left circumflex, and left anterior descending artery disease, respectively. Patients with an occluded culprit artery were more commonly men and had ST-segment deviation ≥1 mm. One-year outcomes, including death (3.5% vs 3.0%, p = 0.68) and myocardial infarction (8.4% vs 9.6%, p = 0.47), did not differ significantly between patients with versus without occluded culprit arteries, respectively. In conclusion, the present study demonstrates that the culprit artery is totally occluded in approximately 1 in 5 patients presenting with NSTEMI and single-vessel disease; however, the presence of total occlusion in NSTEMI was not associated with an incremental hazard of death or reinfarction at 1 year.