title: Monophasic action potentials of the right atrium during atrial fibrillation in man.
abstract: In 28 patients with established atrial fibrillation [AF], right atrial monophasic action potentials [MAP] were recorded before DC shock. A close correlation was found between the atrial rate and MAP duration of the fibrillatory waves [FW]. The duration of MAPs ranged between 1 and 6 mV. The atrial rate ranged between 311 and 578 per minute, the highest rates were found during lone AF. In two patients in whom cardioversion failed, a prolongation of right atrial MAP duration of the FW was noted. The efficacy of DC shock and the maintenance of sinus rhythm after cardioversion was greater in patients with AF having a slower rate and a longer MAP.
mesh_terms: D000328:Adult; D000368:Aged; D001281:Atrial Fibrillation / Q000503:physiopathology* / Q000628:therapy; D004554:Electric Countershock; D004562:Electrocardiography; D005260:Female; D006325:Heart Atria / Q000503:physiopathology*; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged