Prognostic Value of GRACE Score and Left Ventricular Ejection Fraction in Non-ST-Segment Elevation Myocardial Infarction

Abstract

Background: To provide more useful information due to the lack of published results to date, we analyzed the 3-year clinical outcomes of patients with non-ST-segment elevation myocardial infarction (NSTEMI) using the Global Registry of Acute Coronary Events (GRACE) score and the degree of left ventricular ejection fraction (LVEF).

Methods: In total, 4558 patients were stratified into two groups: GRACE score > 140 (group A) and GRACE score ≤ 140 (Group B). Each group was further subdivided into heart failure (HF) with reduced EF (HFrEF), HF with mildly reduced EF (HFmrEF), and HF with preserved EF (HFpEF). The primary outcome was all-cause mortality, and the secondary outcomes were cardiac death (CD), non-CD, recurrent MI, and hospitalization for HF (HHF).

Results: After adjustment, in Group A, the 3-year rates of all-cause mortality (p < 0.001 for all), CD, and HHF were higher in the HFrEF subgroup than in the HFmrEF and HFpEF subgroups, with similar outcomes between the HFmrEF and HFpEF subgroups. In Group B, the HFrEF subgroup had higher CD (p = 0.019) and HHF rates than did the HFmrEF subgroup and higher all-cause mortality (p = 0.001), CD (p < 0.001), and HHF rates than the HFpEF subgroup. All-cause mortality rate between the HFrEF and HFmrEF subgroups was similar, whereas the HFmrEF subgroup had a higher all-cause mortality rate than did the HFpEF subgroup (p = 0.022). Group A had worse clinical outcomes than Group B across all LVEF subgroups.

Conclusion: Although the HFrEF subgroup had a higher all-cause mortality rate than did the HFpEF subgroup, all-cause mortality patterns between the HFrEF and HFmrEF subgroups and between the HFmrEF and HFpEF subgroups varied according to the GRACE score. However, broader studies with a larger number of patients are needed.