Early- and late-term clinical outcome and their predictors in patients with ST-segment elevation myocardial infarction and non-ST-segment elevation myocardial infarction

Backgrounds: The disparity between ST-segment elevation myocardial infarction (STEMI) and non-STEMI (NSTEMI) remains controversial. We compared clinical outcomes and prognostic factors between STEMI and NSTEMI using large-scale registry data.

Methods: We recruited 28,421 patients with STEMI (n=16,607) and NSTEMI (n=11,814) between November 2005 and April 2010 from a nationwide registry in Korea. We performed landmark analysis of cardiac death, recurrent acute myocardial infarction (re-AMI), revascularization, and major adverse cardiac events (MACE) at 30 days (early term) and 1 year (late term) after admission.

Results: Patients with NSTEMI had a greater number of co-morbidities than STEMI patients. Early term MACE (6.9% vs. 4.5%, p<0.001) and cardiac death (6.1% vs. 3.7%, p<0.001) were higher in STEMI patients. However, late-term MACE (8.0% vs. 9.1%, p=0.007), cardiac death (1.9% vs. 2.6%, p=0.001), and re-AMI (0.6% vs. 1.3%, p<0.001) were lower in the STEMI group. The independent predictors of cardiac death were old age, renal dysfunction, LV dysfunction, Killip class, post-thrombolysis in myocardial infarction (TIMI) flow, and major bleeding in both groups. Female gender, previous ischemic heart disease, diabetes, current smoking, multivessel disease, and body mass index were MI type- or time-dependent predictors.

Conclusion: The STEMI group displayed poor early term clinical outcome, whereas the NSTEMI group displayed poor late-term clinical outcome. The STEMI and NSTEMI groups had different predictor profiles for cardiac death, suggesting that different strategies are required for improving the late-term outcome of STEMI and NSTEMI patients.