Demographic Trends and Changes in the Pre- and In-Hospital Medical Management of Acute Myocardial Infarction During the First 12 Months of the COVID-19 Pandemic in Mie Prefecture　― Report From the Mie ACS Registry ―

Background: Even though hospital admissions for acute myocardial infarction (AMI) decreased globally during the COVID-19 pandemic in early 2020, limited information is available on subsequent demographic trends in the number of cases and management of AMI through the first 12 months of the COVID-19 pandemic. Methods and Results: We assessed demographic trends, patient characteristics, and AMI outcomes (n=730) during the first 12 months of the COVID-19 pandemic and compared them with corresponding months during the control period (February 2016–January 2020; n=2,742) using data from the Mie ACS Registry. Although a 25.8% reduction in hospitalizations for AMI was observed in the 3 months following the declaration of a state of emergency (47.7 vs. 64.3/month; P=0.002), the total number of AMI patients was similar between the 12-month COVID-19 and control periods (60.8 vs. 57.2/month; P=0.58). The number of patients requiring direct ambulance transport was lower in the first half of the COVID-19 than control period (44.4% vs. 51.5; P=0.028). In-hospital mortality was higher in the second half of the COVID-19 than control period (8.9% vs. 5.8%; P=0.032). Conclusions: Through the first 12 months of the COVID-19 pandemic, the number of AMI cases was similar to that in previous years. The COVID-19 pandemic changed the behavior of AMI patients and both pre- and in-hospital medical management, which significantly affected the severity and prognosis of AMI.