HealthDay News — Exposure to fire is associated with activation of platelets, increased thrombus formation, and impaired vascular function, promoting myocardial ischemia and injury, according to a study published in the April 4 issue of Circulation.
Amanda L. Hunter, MB, ChB, from the University of Edinburgh in the United Kingdom, and colleagues conducted an open-label crossover study involving 19 healthy firefighters who performed a standardized training exercise in a fire stimulation facility or light duties for 20 minutes.
The researchers found that core temperature increased and weight decreased after fire stimulation training (P <.001 for both). Exposure to fire simulation correlated with increased thrombus formation under low- and high-shear conditions compared with control (both P <.001), as well as increased platelet-monocyte binding (P =.03). A dose-dependent increase was seen in forearm blood flow with all vasodilators (P <.001); in response to acetylcholine and sodium nitroprusside, the increase was attenuated by fire simulation (P =.01 and .004). This correlated with an increase in fibrinolytic capacity, asymptomatic myocardial ischemia, and concentrations of plasma cardiac troponin I (P =.010).
“Our findings provide pathogenic mechanisms to explain the association between fire suppression activity and acute myocardial infarction in firefighters,” the authors write.
- Hunter AL, Shah ASV, Lanagrish JP, et al. Fire simulation and cardiovascular health in firefighters. Circulation. 2017;135:1284-1295. doi: 10.1161/CIRCULATIONAHA.116.025711
- Kales SN, Smith DL. Firefighting and the heart. Circulation. 2017;135:1296-1299. doi: 10.1161/CIRCULATIONAHA.117.027018