Mortality After Non–ST-Segment Elevation Myocardial Infarction

Background

Non–ST-segment elevation myocardial infarction (NSTEMI) due to coronary artery disease (CAD) can lead to reduced left ventricular ejection fraction (LVEF) and increased mortality. However, the interplay between LVEF and obstructive CAD on mortality has not been examined in patients with NSTEMI.

Objectives

The purpose of this study was to examine the combined prognostic impact of LVEF and CAD on mortality following an NSTEMI.

Methods

We included patients referred to coronary angiography due to first-time NSTEMI with obstructive CAD registered in the Western Denmark Heart Registry. Patients were grouped according to LVEF (>50%, 41% to 50%, and ≤40%) and the extent of obstructive CAD defined by vessel disease (VD) (1VD, 2VD, and 3VD). Five-year cumulative incidence proportions and HRs of mortality were calculated. Excess mortality was assessed by comparison with a sex- and age-matched general population cohort.

Results

In total, 8,770 patients with NSTEMI and obstructive CAD were included between 2010 and 2021. The lowest 5-year mortality was observed for patients with LVEF >50% and 1VD (9%), followed by an increase with decreasing LVEF and increasing CAD. The highest mortality was observed for patients with LVEF ≤40% and 3VD (46%; adjusted HR 3.05; 95% CI: 2.51-3.70). This relationship was confirmed by comparison with the matched general population, where patients with LVEF ≤40% and 3VD had 24% higher absolute mortality.

Conclusions

In patients with NSTEMI, the combined information on LVEF and the extent of obstructive CAD was associated with an increasing 5-year mortality. A comparison with a matched general population confirmed the findings.