Angina pectoris prevalence and sick leave burden one year after MINOCA

Background Myocardial infarction with non-obstructive coronary arteries (MINOCA) represents approximately 5-10% of all myocardial infarctions (MI), with heterogenous etiologies and insufficient knowledge on symptom burden after the acute phase. Purpose To evaluate the prevalence of angina and sick leave in MINOCA, using individuals with MI due to coronary artery disease (MI-CAD) as control. Methods This observational study used prospectively collected data from the Swedish national quality register SWEDEHEART. All individuals with invasively assessed, first time MI between 2005 – 2022, available at one year follow-up were included and categorized as MINOCA (normal coronary arteries or <50% lumen obstruction) or MI-CAD (>50% lumen obstruction). We excluded subjects with previous coronary intervention, previous heart failure, tachy- or bradyarrhythmia at admission and not fully revascularized MI-CAD. Chest pain was assessed by a clinical nurse and angina graded according to the Canadian Cardiovascular Society, excluding non-ischemic chest pain. Occupational status was self-reported. Results We included N=46 428 individuals (mean age 62, 71% male; MINOCA n= 5281/MI-CAD n=41 157). Subjects with MINOCA were predominantly females, more commonly divorced or widowed, non-smoking and had a higher degree of hypertension, hyperlipidemia, and chronic obstructive pulmonary disease, compared to fully revascularized MI-CAD. Angina prevalence was 11.6 % and 8.8% in MINOCA and MI-CAD respectively (p <0.001). After adjustment for background variables clinically relevantly associated to both MI type and anginal status OR was 1.21 [95% CI 1.10 – 1.34] (Figure 1). Sick leave was more common in MINOCA both at index care, and at one year (8.0 vs 5.6 % and 13.4 vs 10.9%, both p <0.001) (Figure 2). Conclusion MINOCA patients suffer significant distress, with higher levels of angina and sick leave compared to fully revascularized MI-CAD counterparts. Further research on causes of ischemic symptoms in this heterogenous condition is warranted.