Complete infrahisian atrioventricular block after endocavitary shock delivered by an automatic implantable cardiac defibrillator.
Transient reproducible complete infrahisian atrioventricular block occurred after endocavitary cardioversion of ventricular tachycardia and ventricular fibrillation by an automatic implantable cardiac defibrillator in a patient with left bundle branch block and baseline borderline H-V interval. Six months later, a permanent complete atrioventricular block occurred after repetitive endocavitary shocks. Several hypothetical mechanisms may explain this infrahisian atrioventricular block a "fatigue" phenomenon of the His-Purkinje system, vagally mediated atrioventricular block, and/or ablation of the His conduction system. The last seems to be the most probable, which would justify implantation of an automatic implantable cardiac defibrillator with backup pacing in all patients, especially in the presence of bundle branch block.
Babuty
D
D
Cardiology and Electrophysiology Service, Trousseau Hospital, Tours, France.
Charniot
J C
JC
Fauchier
J P
JP
D000328:Adult; D002036:Bundle of His / Q000503:physiopathology; D002304:Cardiac Pacing, Artificial; D017147:Defibrillators, Implantable / Q000009:adverse effects*; D004562:Electrocardiography; D006327:Heart Block / Q000209:etiology* / Q000503:physiopathology / Q000628:therapy; D006801:Humans; D008297:Male; D017180:Tachycardia, Ventricular / Q000628:therapy; D014693:Ventricular Fibrillation / Q000628:therapy