The universal classification is an independent predictor of long-term outcomes in acute myocardial infarction

Abstract

The long-term outcomes of patients with acute myocardial infarction (AMI) according to the universal classification (UC) are unknown. We investigated whether the outcome of these patients is better predicted by the UC than the ST-segment classification (STC). We conducted a retrospective study of 348 consecutive patients with AMI with mean follow-up of 30.6 months. The primary outcome was major adverse cardiovascular events (MACE) [composite of all causes of death and AMI]. The study included ST-segment elevation (STEMI) = 168 (48%), non-ST-segment elevation (NSTEMI) = 180 (52%), Type 1 = 278 (80%), Type 2 = 55 (15.8%), Type 3 = 5 (1.4%), Type 4a = 2 (0.6%), Type 4b = 5 (1.4%), and Type 5 = 3 (0.9%). During follow-up, 102 (29.3%) patients had MACE, 80 (23%) patients died, and 31 (8.9%) had an AMI. The adjusted risk of MACE was similar for NSTEMI and STEMI (HR 1.26, 95% CI 0.77-2.03, P = .35) but was significantly lower for patients with Type 2 AMI as compared to Type 1 (HR 0.44, 95% CI 0.21-0.90, P= .02). The UC, peak troponin levels, discharge glomerular filtration rate <60 ml/min per 1.73 m(2), and thrombolysis in myocardial infarction risk score were independent predictors of MACE (all, P<.05). The UC is an independent predictor of long-term outcomes in AMI patients compared to the STC. Type 2 AMI has less than half the risk of MACE as Type 1 AMI. Future studies should report outcomes of AMI patients according to the UC types.