Paroxysmal and chronic atrial fibrillation in airman certification.

Of the 757,693 airmen with valid FAA medical certificates on Oct. 31, 1974, 125 (all males but one) had a history of paroxysmal atrial fibrillation. Episodes of paroxysmal atrial fibrillation occurred once in 91, twice in 14, and more than twice in 20 airmen, and were attributed to one or more of 23 factors in 72 of the medical records studied. Associated symptoms reported in 27 records were considered serious enough to produce pilot incapacitation. Chronic atrial fibrillation was idiopathic in all but one airman, who developed this arrhythmia following atrial septal defect repair. Medical records report no associated symptoms, and heart rates, resting and in response to exercise, were reported as within normal limits.