Background: Paroxysmal atrial tachyarrhythmias have been frequently detected in patients paced for atrioventricular block. However, it is not yet clear which is the actual incidence of such arrhythmias and if they were preexisting but not recognized, or if they could be related to the device.
Methods: One hundred and forty-five patients with a diagnosis of second or third degree atrioventricular block were enrolled into the study. One hundred and twenty-four received a pacemaker Medtronic Thera DDD and 21 a Medtronic Thera VDD. High rate atrial episodes were evaluated for 3 months after enrollment. Atrial electrograms documenting paroxysmal atrial fibrillation (AF) were stored and programming of atrial sensitivity and pacemaker diagnostics was very strict in order to exclude short and false positive AF episodes.
Results: Thirty-six patients (35%) in the DDD group and 8 (42%) in the VDD group presented with AF (p = NS). The mean number o