Effect of live-fire training on ventricular-vascular coupling

Area of Science:

• Physiology
• Occupational Health
• Cardiovascular Science

Background:

• Cardiovascular events are a primary cause of firefighter line-of-duty deaths.
• Fire suppression activities acutely increase cardiovascular risk.
• Ventricular-vascular coupling (VVC) describes the interaction between heart function and vascular load.

Purpose of the Study:

• To investigate the impact of live-fire training on VVC in firefighters.
• To assess changes in cardiac and vascular parameters post-firefighting.

Main Methods:

• Sixty-eight male and fifteen female firefighters underwent hemodynamic and cardiac assessments before and after 3 hours of live-fire training.
• Left ventricular function (ejection fraction, ventricular elastance) and vascular load (arterial elastance) were measured.
• Ventricular-vascular coupling was quantified as the ratio of arterial elastance to ventricular elastance, indexed to body surface area.

Main Results:

• Ejection fraction decreased significantly post-training (p < 0.01).
• Arterial elastance significantly increased (p < 0.01) due to decreased stroke volume.
• The ventricular-vascular coupling ratio significantly increased (p < 0.01), indicating a mismatch.

Conclusions:

• Live-fire training increases arterial elastance without altering ventricular elastance in healthy firefighters.
• The resulting increase in VVC ratio and reduced ventricular systolic function may elevate cardiovascular risk.
• Findings highlight a potential mechanism for increased cardiac events in firefighters after strenuous activity.