Pacemaker-Mediated Tachycardia from a Single Chamber Temperature Sensitive Pacemaker

This report describes a case of pacemaker-mediated tachycardia from a single chamber temperature sensitive rate modulated pacemaker. The patient experienced diaphragmatic pacing that produced an increase in right ventricular blood temperature. This temperature increase was sensed by the pacemaker and led to sustained upper rate limit pacing. Decreasing the ventricular output to prevent diaphragmatic capture eliminated further episodes of pacemaker-mediated tachycardia.