title: First degree atrioventricular block.
abstract: First degree A-V block, defined as prolongation of the PR interval on the surface electrocardiogram, is a not uncommon finding on electrocardiographic screening of asymptomatic young individuals. Prevalences of from 0.65% to 1.1% have been reported. In the majority of cases the PR prolongation may be rendered normal by autonomic intervention. Long-term follow-up studies have indicated that although the risk of subsequent coronary artery disease may be slightly increased, the risk of sudden death, syncope or advanced A-V block is not. Apart from the exclusion of organic heart disease, detailed invasive investigation is not warranted. It is a benign condition and as such no restriction on fitness to fly need be made on these individuals, but there may be a case for increased electrocardiographic scrutiny.
mesh_terms: D000328:Adult; D000337:Aerospace Medicine; D001283:Atrioventricular Node / Q000503:physiopathology*; D002036:Bundle of His / Q000503:physiopathology; D002037:Bundle-Branch Block / Q000175:diagnosis; D003327:Coronary Disease / Q000453:epidemiology; D003937:Diagnosis, Differential; D004562:Electrocardiography; D005500:Follow-Up Studies; D006327:Heart Block / Q000145:classification / Q000175:diagnosis*; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012306:Risk