Cardiac death remains a substantial contributor to on-duty mortality of U.S. firefighters, and drivers of this trend may not be well identified by the current screening approaches, according to a brief report published Oct. 21 in JACC: Advances.

Sandy Y. Joung, MBA, MSHS, Alan C. Kwan, MD, et al., examined temporal trends in duty-related cardiac death among U.S. firefighters and systematically reviewed available autopsy findings to determine if observed pathoanatomic patterns align with current prevention strategies. U.S. Fire Administration records of on-duty firefighter fatalities from 1990 to 2025 were queried, and firefighters aged 15 to 74 years (mean age of 46 years) were included. Primary trend analyses were restricted to 1999 through 2019 to reduce distortion from excess COVID-related mortality.

Deaths attributed to sudden "cardiovascular event/heart attack" were classified as cardiac deaths.

Of 3,401 on-duty fatalities, 43% were attributed to cardiac causes. Among the 2,097 firefighters in the primary trend analysis, there was a decrease in total deaths; however, the likelihood that an on-duty death was cardiac increased by 2% per year. Moreover, among the 42% of this group who were career firefighters, there was a 4% increase per year through 2019 (p=0.002), but in the 58% who were volunteer firefighters, no significant temporal trend was observed.

In the general U.S. population, the trend was the opposite: Cardiac deaths as a proportion of all deaths fell 1% per year.

Fire Fighter Fatality Investigation and Prevention Program reports documented 803 deaths from 1997 through 2022; 35% had autopsy data. Among cases with autopsy data, mean age was 46 years, 98% were men and 88% of deaths were attributed to cardiac disease.

Among on-duty firefighter deaths, 57% involved coronary artery disease (CAD) and 79% involved left ventricular hypertrophy (LVH). Notably, 43% of decedents with LVH had no obstructive CAD.

"…standard echocardiography may be of limited utility in this physically active workforce in whom physiologic exercise adaptation can resemble early structural disease," write the authors, emphasizing that "…further research is needed to understand the underlying mechanisms and optimal approaches to direct evaluation of the myocardium when refining firefighter cardiovascular risk stratification."