Beyond “normal” coronaries: the hidden long-term risk of myocardial infarction with non-obstructive coronary artery disease
M Ferreira, M Mendonca, G Abreu, F Sousa, F Escorcio Silva, M Rodrigues, S Freitas, E Henriques, S Borges, A Cardoso, I Ornelas, A Drumond, A C Sousa, R Palma dos ReisAbstract
Background
Some studies showed that the prognosis for patients with Myocardial Infarction (MI) with Non-Obstructive Coronary Artery Disease (MINOCA) is more favourable compared to those with Obstructive Coronary Artery Disease (MI-CAD). However, it has been proven to be worse than the general population.
Objective
Evaluate the prognostic value of MINOCA compared with a general population without apparent CAD from a Southern European population.
Methods
A single-centre, prospective, and observational cohort study was performed from January 2000 to December 2023 with a total of 1,524 individuals. Patients were considered MINOCA if their coronary angiogram was classified as zero by the Leaman score. All participants underwent clinical observation, completed a survey form including demographic and traditional risk factors, and underwent biochemical analysis. The primary outcome was all-cause cardiovascular (CV) events [MI, revascularisation, heart failure, stroke, peripheral arterial disease (PAD) and death]. Cox regression analysis identified variables independently associated with CV events and assessed the risk (HR) in these populations. The Kaplan-Meier estimated event-free survival over time.
Results
Of the 1,524 participants, 87 (5.7%) had MINOCA and 1,437 (94.3%) were normal individuals without symptomatic CAD. Among the 87 MINOCA patients, 14 (16.1%) had CV events, vs 108 (7.5%) in the normal group. The Kaplan-Meier analysis indicated that patients with MINOCA had a lower event-free probability throughout the follow-up period. Specifically, at the end of 15 years, the event-free probability was 52.2% in MINOCA vs 88.7% in the normal group. After Cox regression analysis, the risk of CV for patients with MINOCA was approximately 5 times higher compared with the normal group (p<0.0001). The other variables identified as independently associated with CV events were male sex (p=0.018), age (p<0.0001), smoking (p=0.001), and hypertension (p=0.001).
Conclusion
In this prospective cohort, patients with MINOCA had a substantially higher long-term risk of CV events than individuals without CAD. Event-free survival was markedly reduced, and MINOCA remained a strong independent predictor of adverse CV outcomes. These findings reinforce that MINOCA is not a benign condition and highlight the need for rigorous risk stratification and sustained secondary prevention in this population.MINOCA vs controls