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.

Long-term follow-up of patients with relatively high effective defibrillation threshold during cardioverter defibrillator implantation with endocardial leads.

OBJECTIVE: We evaluated the 15-year outcome of patients with an implantable cardioverter defibrillator (ICD) and a relatively high defibrillation threshold (DFT). METHODS: After ICD implantation, patients were allocated to 3 groups: DFT 24-25 J (16 patients), effective defibrillation with 18-20 J (20 patients) and DFT <15 J (118 patients). An abbreviated DFT test was used during the implantation. The follow-up duration was 15.5 years. RESULTS: There was no significant difference between the survivals of the 3 groups, with a mean survival of 7.30 +/- 4.51 years. In the ventricular fibrillation zone, 99.69, 100 and 100% of the episodes were successfully defibrillated in the 3 groups, respectively. In the ventricular tachycardia zone, 83.24, 92.86 and 95.39% of the episodes were terminated with pacing therapy. The small differences between the groups were not statistically significant. The testing method did not have an impact on survival or therapy success rate. CONCLUSIONS: A 24-joule DFT with a 10-joule safety window is safe during 15 years of follow-up.

Permanent Cardiac Pacing in Octogenarians.

A significant percentage of patients in need of a permanent pacemaker are older than 80 years. The implantation policy may be determined either by the patient's physical activity or by chronologic age. The trend in pacemaker implantation in patients over 80 during the last 10 years in our institution was evaluated and compared with the trend in the patients younger than 80 at the time of implantation. Of 519 patients who had primary pacemaker implantation, 152 (29%) were older than 80 at the time of the procedure. Another 189 patients had second implantation procedures, and 80% of them were older than 80 years. Complete atrioventricular block was the indication for pacing in 44 Â+/- 11% and sick sinus syndrome in 25 Â+/- 7%. The tendency to implant dual-chamber pacemakers increased from 0% during 1985 to 76% in 1994, including 69% DDD and 31% DDDR, but the transition was faster in the younger group. By 1994, there was no difference in the incidence of advanced pacing systems in the 2 age groups. During 1985, only VVI pacemakers were replaced, and during 1994, less than 10% were replaced with simple ventricular pacing units. Pacing system upgrading was frequent during the second half of the decade. The success and complication rate of implantation did not differ in the 2 groups.