['The insertion and management of a temporary transvenous pacemaker can be a lifesaving procedure in the emergency department setting. We compare the success and complication rates associated with temporary transvenous pacemaker insertion between physicians trained in either emergency medicine or cardiology.', 'This was a retrospective medical record review of all patients with a billing code for temporary transvenous pacemaker insertion at our institution between July 1999 and December 2002. Patients were excluded if the temporary transvenous pacemaker was not supervised by an attending physician or was placed under fluoroscopy or if the indication for pacing was asystole. Cases were reviewed by 2 physicians certified in emergency medicine and categorized by the specialty training of the attending physician providing direct supervision.', 'During the review period, 10 emergency medicine faculty and 8 cardiologists directly supervised 141 of the 158 temporary transvenous pacemaker insertions in 154 patients. Twenty-four were placed for asystole, 4 were placed under fluoroscopy, and 13 were placed without direct attending supervision, leaving a total of 117 cases (30 emergency medicine, 87 cardiology) for review. The procedure was successful 97% (95% confidence interval [CI] 90% to 100%) of the time for emergency medicine faculty and 95% (95% CI 91% to 100%) of the time for cardiology faculty. Complications were seen in 23% (95% CI 7% to 39%) of the temporary transvenous pacemakers inserted by emergency medicine attending physicians and 20% (95% CI 11% to 28%) of the temporary transvenous pacemakers inserted by cardiologists. There was no statistical difference in errors between the specialties, and no complication resulted in death or prolonged disability.'] Are emergency medicine-trained physicians proficient in the insertion of transvenous pacemakers?