Comparing pharmacotherapy in MINOCA versus medically managed obstructive acute coronary syndrome

Abstract

Most prior studies have compared myocardial infarction with non-obstructive coronary arteries (MINOCA), to obstructive acute coronary syndrome (ACS) often requiring revascularisation. However, these were subject to treatment bias given the significant differences in management. This study uniquely compares the management and outcomes of MINOCA patients with a medically managed obstructive ACS (M-ACS) population. We retrospectively analysed registry data for consecutive patients admitted to the Gold Coast University Hospital with ACS requiring coronary angiography and identified patients with MINOCA and M-ACS. Baseline characteristics, pharmacological therapy and in-hospital outcomes were compared. In hospital outcomes were composite NACE, heart failure, stroke and major bleeding. Multivariate regression analysis was also performed to identify independent predictors of MINOCA. Multivariate regression analysis was also performed to identify independent predictors of MINOCA. We identified 139 patients with MINOCA and 142 patients with medically managed obstructive ACS (M-ACS). Multivariate regression analysis also identified female sex and cancer as independent predictors of MINOCA with odds ratios of 5.57 and 3.01, respectively. MINOCA patients were significantly less likely to receive cardioprotective medications at admission and discharge, specifically aspirin, beta-blockers, ACE-I and statins, compared to those with M-ACS. While mortality was higher among M-ACS patients (0.0% vs. 3.6%; p = 0.03), no significant differences were noted for composite NACE, heart failure, stroke and major bleeding. MINOCA patients have similar outcomes to M-ACS. Despite this, we noted a discrepancy in the use of cardioprotective medications. We also identified female sex and cancer were independent predictors of MINOCA. This may represent a missed opportunity to prevent adverse events among patients with MINOCA. Large, randomised trials are required to provide more definitive evidence.