Transient cardiac dysfunction and pulmonary edema in exertional heat stroke

Exertional heat stroke is a medical emergency that uncommonly results in severe cardiac dysfunction. The military physician diagnosed a 19-year-old military recruit from an elite unit to have exertional heat stroke. Immediate treatment in the field with rapid ice water cooling and vigorous fluid administration resulted in pulmonary edema. Transthoracic echocardiography on admission to the emergency department revealed moderate reduction in left and right ventricular function. After treatment, within a few days, rapid myocardial recovery was noted and persisted after 6 months of follow-up. Possible mechanisms of cardiac dysfunction in exertional heat stroke and treatment strategies are discussed. It is suggested that intravenous fluid administration to patients with suspected exertional heat stroke should preferably be done with appropriate hemodynamic monitoring and after cardiac dysfunction has been ruled out.