Impact of occluded culprit arteries on long-term clinical outcome in patients with non-ST-elevation myocardial infarction: 48-month follow-Up results in the COREA-AMI registry

Background: The prognostic impact of occluded culprit arteries in non-ST-elevation myocardial infarction (NSTEMI) patients beyond 12 months has not been investigated. Objectives: The impact of occluded culprit arteries on a composite of cardiac death (CD), recurrent nonfatal MI (RMI), and target vessel revascularization (TVR) in patients who presented with NSTEMI was investigated during a 48-month follow-up using propensity-score (PS) matching. Methods: A total of 2,878 NSTEMI patients in the COREA-AMI (COnvergent REgistry of cAtholic and chonnAm university for Acute MI) Registry were classified according to the angiographic flow of culprit arteries (occlusion [OC], n=1,070; nonocclusion, n=1,808). After PS matching, the incidence of the primary end-point, a composite of CD, RMI, and TVR was compared. Results: The median follow-up duration was 47.3 months (IQR 32.7-66.2). In the PS-matched population, the 48-month cumulative rates of the primary end-point (27.5% vs. 17.9%, P<0.001) and each event were higher in the OC group (CD: 9.0% vs. 5.4%, RMI: 16.3% vs. 9.4%, TVR: 10.5% vs. 5.6%, respectively, P<0.05). In multivariate Cox regression analysis, occluded culprit arteries showed the significant statistical impact on the primary end-point (HR 1.689 [1.385-2.059], P<0.001) and each event (CD: 1.736 [1.218-2.475], RMI: 1.918 [1.468-2.505], TVR: 2.042 [1.453-2.869], respectively, P<0.05). Furthermore, in the 12-month landmark analysis, occluded culprit arteries were still associated with higher risk of primary end-point beyond 12 months (P<0.001). Conclusions: Occluded culprit arteries were independently associated with the higher risk of CD, RMI, and TVR in NSTEMI patients during the 48-month follow-up. (J Interven Cardiol 2014;27:12-20).