Sex differences in patients with working diagnosis of myocardial infarction with nonobstructive coronary arteries (MINOCA)

Myocardial infarction with nonobstructive coronary arteries (MINOCA) constitutes 3-15% of all acute myocardial infarctions. Women are more frequently diagnosed with MINOCA, although the influence of sex on long-term outcomes is still unclear. In this study we aimed to compare sex-based differences in baseline characteristics and clinical outcomes in patients with suspected MINOCA. We have retrospectively analyzed 6063 patients diagnosed with MINOCA (3220 females and 2843 male patients) from combined 3 large polish registries (PL-ACS, SILCARD and AMI-PL). Male patients were significantly younger (63 (55-74) vs. 71 (61-79) years, p < 0.05) and less frequently diabetic (20.1% vs. 24.1%, p < 0.05). Mortality was significantly higher in male population (11.8% vs. 10.2%, p < 0.05 at 1 year and 17.6% vs. 15.0%, p < 0.05 at 3 years). Male sex was an independent predictor of both mortality (HR = 1.29; CI 1.11-1.51; p < 0.05) and myocardial infarction (HR = 1.39; CI 1.1-1.75, p < 0.05) at 3 years follow-up. All-cause readmission rates were similar in male and female patients both at 1 year (46.0% vs. 44.4, p = 0.2) and 3 years follow-up (56.4% vs. 56.5%, p = 0.93). However, cardiovascular readmissions were more prevalent in male patients at both timepoints (33.9% vs. 29.10%, p < 0.05 at 1 year, and 41.0% vs. 37.6%, p < 0.05 at 3 years). This large-scale registry-based analysis demonstrated higher 3 years rates of adverse events, including death and MI among male patients with suspected MINOCA.