Pathoanatomic Findings Associated With Duty‐Related Cardiac Death in US Firefighters: A Case–Control Study

BACKGROUND: Sudden cardiac death accounts for the greatest proportion of duty‐related deaths among US firefighters. Increased understanding of the pathoanatomic causes of sudden cardiac death and the risk associated with underlying cardiac pathologies is needed to develop evidence‐based screening recommendations. METHODS AND RESULTS: Using autopsy data for duty‐related firefighter fatalities occurring between 1999 and 2014, this retrospective case–control study compared cardiac findings of male firefighters aged 18 to 65 years who died on duty of cardiac‐related causes with those who died of noncardiac trauma‐related causes. Data from 276 cardiac cases and 351 noncardiac trauma controls were analyzed. Among cardiac cases, the most prevalent (82%) underlying pathoanatomic substrate was comorbid coronary heart disease and cardiomegaly/left ventricular hypertrophy. Cardiac cases had a higher prevalence of cardiomegaly (heart weight >450 g), left ventricular hypertrophy (left ventricular wall thickness ≥1.2 cm), and severe coronary artery stenosis (≥75%) than trauma controls (all P<0.001). In multivariate analyses, heart weight >450 g, coronary artery stenosis ≥75%, and evidence of a prior myocardial infarction were strong independent predictors of cardiac death, with odds ratios of 6.1 (95% confidence interval, 3.6–10.4), 9.3 (95% confidence interval, 5.3–16.1), and 6.2 (95% confidence interval, 3.4–11.3), respectively. CONCLUSIONS: The majority of cardiac fatalities had evidence of both coronary heart disease and increased heart mass, and each condition was independently associated with a markedly elevated risk of cardiac death. Targeted screening for coronary heart disease, increased heart mass, and evidence of prior myocardial infarction should be considered to reduce duty‐related cardiac deaths among firefighters.