Two Varieties of the Onset of Atrial Fibrillation Studied by Monophasic Action Potential Recording

Abstract

Two types of the initiation of atrial fibrillation are demonstrated in the continuous recordings of right atrial monophasic action potentials. In the first way, more common, atrial fibrillation takes place suddenly after an extrasystolic atrial beat, in the second one it develops gradually after atrial tachycardia. In the first type the micro reentry starts from the beginning, in the second type only after sustained focal atrial tachycardia.