Many pacemaker patients have vague symptoms following implantation. It is often difficult for the physician to ascertain if they are cardiac in origin. A new pacemaker feature has been introduced, Patient-Triggered Event Records (PTER), to help the physician with this diagnosis. The PTER is a continuously running event record which stores the cardiac rhythm and rate. Brief application of a magnet will transfer the record into the device's memory. The data recorded will be the 97 events prior to the magnet application and the 30 events following magnet removal. The exact state of pacing (atrial and ventricular sensing/pacing, or premature ventricular events) and the rate of the ventricular events will be graphically displayed by the programmer for all 127 events. Thus, the exact pacer and cardiac rhythm can be determined during the period of the symptomatic episode. A total of three PTER's can be stored within the device. If a fourth is recorded, it will replace the oldest record. Three pacemakers with the PTER feature were tested in vitro with five different simulated cardiac rhythms. A beat-by-beat comparison between the PTER and the 15 simulated test rhythms revealed a 100% accurate documentation by PTER. Sixteen pacemaker patients which have the PTER feature were monitored using a King of Hearts for a total of 43 symptomatic events. The PTER records produced clinically relevant information 98% of the time while the King of Hearts produced clinically relevant information 81% of the time. A comparison of costs of the two different methods of monitoring these patients, was $2,432 versus $4,480 for the PTER and loop event monitor respectively. The PTER is an accurate, lower cost method for monitoring and diagnosing symptomatic pacemaker patients. The PTER can be used as the first diagnostic tool in troubleshooting patients with paroxysmal symptoms in the pacemaker clinic population.