Prognostic factors of patients with myocardial infarction with nonobstructive coronary artery disease: a seven-year longitudinal follow-up

Abstract Background Myocardial infarction with nonobstructive coronary arteries (MINOCA) is a common condition associated with major adverse events (MAE). Unlike obstructive coronary artery disease (OCAD), data regarding the prognosis of MINOCA are scarce. Methods We conducted a retrospective study among consecutive patients with MINOCA in a large tertiary medical center in Israel between the years 2005–2018. We assessed parameters associated with MAE, defined as all-cause mortality or recurrent MI. Patients with probable alternative cause for myocardial injury, as stress-induced cardiomyopathy and myocarditis, were excluded. Results Among 36,501 admitted with AMI during the study period, 1,544 patients (4.2%) had MINOCA. The mean age was 61±13, and 710 (46%) were females. At a median follow-up of 7 years, the MAE rate was 17%, as 153 (9.9%) died, and 117 (7.5%) had recurrent MI. ST-elevation MI at presentation and older age were associated with increased 30-day MAE. In multivariate models, independent factors associated with MAE were female gender (HR=0.58; 95% CI 0.43–0.76), age (HR=1.04; 95% CI 1.03–1.05), left ventricular ejection fraction (LVEF) <40% (HR=2.68; 95% CI 1.74–4.12), increased serum-creatinine (HR=1.11; 95% CI 1.02–1.21), higher hemoglobin (HR=0.81; 95% CI 0.76–0.88), and documented sinus rhythm (HR=0.58; 95% CI 0.38–0.86). Conclusion MINOCA carries an increased risk for long-term MAE. Among MINOCA patients older age, LVEF <40%, and increased serum-creatinine are associated with increased MAE risk, while female gender, higher hemoglobin, and sinus rhythm are associated with lower MAE risk. Funding Acknowledgement Type of funding sources: None.