Syncope as the first sign of complete heart block in a military aviator

Syncope in an aviator may lead to abrupt loss or impairment of control of an aircraft and is thus a threat to safety of flight. Consequently, it is vital to conduct a thorough medical evaluation of any syncopal episode in a pilot or other flight crewmember.

A 28-yr-old male Naval Flight Officer experienced loss of consciousness at a morning briefing, but immediately returned to normal except for tachycardia. He suffered a second episode at a base hospital while on a cardiac monitor. The rhythm was diagnosed as complete heart block and a permanent pacemaker was inserted. This condition is considered disqualifying for U.S. Navy aviation duty.

It is easy to dismiss a single episode of syncope in this age group as due to orthostasis, hangover, or other benign causes. Serious underlying pathology such as complete heart block is rare. The threat to safety of flight, however, dictates that all episodes of syncope in aviators receive a thorough diagnostic work-up.