Pacemaker-mediated tachycardia: tracking of atrial fibrillation during DDD pacing

A 68-year-old man with sick sinus syndrome was treated by implantation of a DDD pacemaker. He subsequently developed a rapid heart rate and was found to have a pacemaker-mediated tachycardia due to tracking of atrial fibrillation by the pacemaker. The tachycardia was abolished by reprogramming the pacemaker, and the patient remained asymptomatic.