Emergency Department Utilization for Acute Myocardial Infarction, U.S., May-September 2018-2023.

Introduction: Exposure to extreme heat and wildfire-related hazards, such as poor air quality, can increase the risk of acute cardiovascular events. This study assessed whether acute myocardial infarction-related emergency department visits increased in 2023-a year of increased heat and wildfire smoke exposure in the U.S.-compared with visits in the 5 preceding years combined. Methods: This serial cross-sectional study identified acute myocardial infarction-related emergency department visits among adults aged ≥18 years from National Syndromic Surveillance Program data using discharge diagnosis codes. Daily mean acute myocardial infarction-related emergency department visit rates per 100,000 all-cause emergency department visits during May-September 2023 were compared with those during May-September 2018-2022 for adults overall and by subgroup. Results: During May-September 2023, the daily acute myocardial infarction-related emergency department visit rate (699.5 acute myocardial infarction-related emergency department visits per 100,000) was 16.5% (95% CI=14.8, 18.2) higher than the rate in 2018-2022 (600.4 acute myocardial infarction-related emergency department visits per 100,000). Overall, acute myocardial infarction-related emergency department visit rates increased across age groups, in both sexes, and in most HHS regions. HHS Regions 2 and 4 reported the largest relative increases in acute myocardial infarction-related emergency department visit rate (27.0% [95% CI=22.9, 31.4] and 30.0% [95% CI=27.7, 32.5], respectively). Conclusions: Acute myocardial infarction-related emergency department visit rates were higher in May-September 2023 than in May-September 2018-2022. Near real-time surveillance data can be leveraged to monitor emergency department visits for acute cardiovascular conditions across different time periods to inform clinical and public health practices.