Spontaneous coronary artery dissection versus atherosclerotic myocardial infarction in young women: a propensity-matched cohort study.

BACKGROUND: Spontaneous coronary artery dissection (SCAD) is an increasingly recognized cause of acute myocardial infarction (AMI) in young women, yet long-term comparisons with atherosclerotic AMI are limited. We compared outcomes in women aged 18-55 years with these two conditions. METHODS: Using the TriNetX research network, we conducted a retrospective cohort study of women aged 18-55 years with SCAD or atherosclerotic myocardial infaction(AMI). Cohorts were balanced by 1:1 propensity score matching, and outcomes assessed at 30 days, 1 year, and 3 years. Sensitivity analyses used age-only, Body Mass Index (BMI) only, and SCAD-without-acute-MI cohorts. RESULTS: After matching, 1,297 patients were included per cohort. Thirty-day mortality was similar (1.2% vs 1.7%; HR 0.72, p = 0.33), but heart failure was less frequent in SCAD (HR 0.44, p = 0.001). SCAD remained associated with lower 1-year heart failure (HR 0.38, p < 0.001) and, at 3 years, lower mortality (HR 0.48, p = 0.002), stroke (HR 0.45, p = 0.012), heart failure (HR 0.33, p < 0.001), ventricular tachycardia (HR 0.48, p = 0.008), angina (HR 0.26, p < 0.001), and rehospitalization (HR 0.34, p < 0.001). Benefits persisted across all sensitivity analyses. CONCLUSIONS: Compared with atherosclerotic AMI, women with SCAD had more favorable intermediate- and long-term outcomes despite similar early mortality. These hypothesis-generating findings may warrant tailored management strategies that merit prospective evaluation.