Worse long-term prognosis in myocardial infarction occurring at weekends or public holidays with insight into myocardial infarction with nonobstructive coronary arteries.

Abstract

The weekend effect in Polish patients with myocardial infarction (MI) treated in the current network of catheterization laboratories is poorly understood. We sought to investigate long‑term prognosis of patients with MI admitted at weekends or public holidays (NWDs) and on working days (WDs). We enrolled 865 patients with MI hospitalized between 2012 and 2017. The long‑term mortality within the median (IQR) time of 68.5 (36.7-78.4) months was determined in 223 patients (25.8%) admitted on NWDs and in 642 (74.2%) on WDs. Patients admitted on NWDs more often had ST‑segment elevation MI (41.3% vs 30.8%; P = 0.005), left anterior descending artery as an infarct‑related artery (38.1% vs 30.2%; P = 0.031) and incomplete reperfusion expressed as Thrombolysis in Myocardial Infarction flow grade 0/1 following primary angioplasty (6.8% vs 1.6%; P <0.001) as compared with those hospitalized on WDs. Myocardial infarction with nonobstructive coronary arteries (MINOCA) occurred less often on NWDs (4% vs 9%, P = 0.019). The all‑cause long‑term mortality was higher in NWD patients as compared with those admitted on WDs (36.3% vs 28.4%; P = 0.037). By the Cox proportional hazards model with time‑dependent covariates, MI on NWDs (hazard ratio, 1.027; 95% CI, 1.022-1.032; P <0.001) but not MINOCA (hazard ratio, 0.971; 95% CI, 0.595-1.583; P = 0.91) was independently associated with long‑term mortality. Patients hospitalized on NWDs as compared with those admitted on WDs had a larger ischemic territory and more often had transmural MI with incomplete epicardial reperfusion, which resulted in a higher long‑term mortality. The latter outcome was not influenced by MINOCA.