10-Year Excess Mortality After First-Time Non-ST-Segment Elevation Myocardial Infarction: The Western Denmark Heart...

In ST-segment elevation myocardial infarction patients, recent evidence showed an almost similar 10-year mortality in 90-day survivors when compared with a matched general population. Whether this finding also applies to contemporary patients with non-ST-segment elevation myocardial infarction (NSTEMI) remains unclear.

The objective of the study was to examine excess mortality in first-time NSTEMI patients treated with percutaneous coronary intervention (PCI) compared with a matched general population during the landmark periods of 0 to 30 days, 31 to 90 days, and 91 days to 10 years.

First-time NSTEMI patients treated with PCI were identified in the Western Denmark Heart Registry from 2010 to 2022. Mortality was compared with a general population cohort matched by age, sex, and calendar year.

The study included 10,748 first-time NSTEMI patients treated with PCI and 53,739 matched individuals. The median follow-up was 6.0 (Q1-Q3: 3.4-9.2) years. NSTEMI patients had higher mortality in all landmark periods than the general population: 1.9% (95% CI: 1.6-2.2) excess mortality from 0 to 30 days (HR: 8.90; 95% CI: 7.40-10.68), 0.5% (95% CI: 0.3-0.7) from 31 to 90 days (HR: 2.54; 95% CI: 2.06-3.15), and 6.1% (95% CI: 4.8-7.5) from 91 days to 10 years (HR: 1.26; 95% CI: 1.21-1.32). Notably, this excess risk was almost exclusively confined to patients with a high comorbidity burden (excess mortality 22.0%; 95% CI: 19.1-24.9).

Among first-time NSTEMI patients treated with PCI, 90-day survivors had a substantially higher 10-year excess mortality than the matched general population. This excess mortality was primarily driven by NSTEMI patients with a high baseline comorbidity burden.