PREVALENCE OF INTRAVENTRICULAR CONDUCTION DISTURBANCES IN A LARGE POPULATION OF AIRCREW MEMBERS

INTRODUCTION: The interpretation of QRS variation and duration in ECC was updated in 2009 by the American Heart Association. The aim of the study was to define the prevalence of intraventricular conduction disturbances (ICD) in a population of aircrew members (AM) using these new recommendations. METHODS: The inclusion population consisted of military and civil AM periodically examined for fitness assessment in the French main aeromedical center (CPEMPN) with a standard 12-lead ECC in each examination. ECG were computerized, analysed by one physician and then stored in a data base. The ECG with ICD were extracted from the data base using an appropriate software. All these ECC were reviewed independently and blindly by a junior then a senior physician, and compared to an equal number of ECC considered as normal to validate the computerized extraction. RESULTS: From 01/01/1996 to 09/30/2010, 69,186 AM [72% male, mean age (ma) 31.3 plus or minus 11 yr] were examined and 222,867 ECC were stored. The reviewed 12-lead ECG revealed 789 Incomplete Right Bundle Branch Blocks (1.14%, ma 32.9 yr, 95.5% male (1.52%), 4.6% female (0.19%)]; 201 Complete Right Bundle Branch Blocks [0.29%, ma 41.1 yr, 94.1% male (0.38%), 5.9% female (0.06%)]; 761 Left Anterior Fascicular Blocks [1.1%, ma 40.4 yr, 88% male (1.35%), 12% female (0.5%)]; 90 Left Posterior Fascicular Blocks [0.13%, ma 31.4 yr, 78% male (0.14%), 22% female (0.1%)]; 55 Complete Left Bundle Branch Blocks [0.08%, ma 50 yr, 75% male (0.08%), 25% female (0.07%)]. DISCUSSION: This work was the first prevalence study using the new standard of ECG interpretation in a large aircrew member population. ICD remain a situation of high importance in this particular population (including fighter pilots) because they can be caused by structural abnormalities in the cardiac conduction tissue or the ventricular myocardium and thus, may lead to in-flight incapacitation.