Intracardiac electrophysiologic studies in the medical evaluation of aviators.

Ten aviators with cardiac symptoms or electrocardiographic abnormalities underwent electrophysiologic testing. Four patients were studied because of symptoms including palpitations, nearsyncope, and sudden cardiac death. Six patients were studied because of electrocardiographic abnormalities including AV block, right bundle branch block, sinus bradycardia, ventricular tachycardia, and questionable Wolff-Parkinson-White syndrome. Three patients with bradycardia and/or AV block were found to have increased vagal tone. A fourth patient had nearsyncope and intra-Hisian block. Of four patients evaluated for palpitations and/or tachycardias; one had nonsustained ventricular tachycardia; one had easily inducible ventricular tachycardia and fibrillation; one had a normal study, and one had coronary artery disease with an unanticipated prolonged HV interval. The diagnosis of congenital right bundle branch block and Wolff-Parkinson-White syndrome were confirmed in the final two patents. Performance of electrophysiologic testing provided objective data to allow appropriate therapeutic and administrative decisions in these aviators.