Pacing system malfunction is a rare cause of hospital admission for syncope in patients with a permanent pacemaker.

Background: Few studies have examined the prevalence of permanent pacemaker (PPM) malfunction among patients with a previously implanted pacemaker admitted to the hospital with syncope. Objective: This study sought to examine causes of syncope in patients with a previously implanted pacemaker admitted to our hospital with syncope. Methods: We retrospectively reviewed our hospital admission database for patients who had both keywords "syncope" and "pacemaker" as their diagnoses from January 1, 1995 until June 1, 2012. One hundred and sixty-two patients who were admitted to the hospital because of syncope and had a PPM implanted prior to the index syncopal episode were included. All patients had pacemakers interrogated during the admission. Two independent physicians examined the discharge summary of each patient and determined the cause of syncope in each case. Results: Of the 162 patients studied, eight (4.9%) were found to have pacemaker system malfunction as a cause of syncope. In 96 patients (59.2%), the cause of syncope could not be determined prior to hospital discharge. Among the identifiable causes of syncope, orthostatic hypotension was most prevalent (16%) followed by vasovagal (6%), severe aortic stenosis (4.3%), atrial arrhythmia (3.1%), acute and subacute infection (3.1%), and other less prevalent causes (3.1%). Conclusion: In this study, PPM system malfunction was rarely a cause of syncope in patients admitted to the hospital with a previously implanted device. (PACE 2013; 36: 109-112)