Abstract 13701: Familial Aggregation of Pacemaker Implantation
Objectives: Symptomatic bradycardia (SB) is a disease resulting primarily from sinus node dysfunction and cardiac conduction disturbances. It is treated by implantation of a permanent pacemaker. Mutations involving ion channels are known to cause SB in some families. The extent of a genetic component causing SB necessitating pacemaker implantation in the general population is unknown. Familial aggregation of a disorder is an indicator of a genetic component in the pathogenesis of a disease. We hypothesized that patients with SB requiring pacemaker implantation are prone to have other relatives with the same disorder.
Methods: Consecutive patients with implanted pacemakers (IP) presenting to routine follow up at our pacemaker clinics were requested to fill a detailed questionnaire regarding family history of pacemaker implantation. Clinical data regarding indication of pacemaker implantation was recorded. An age, gender and race matched control group was recruited from subjects without history of pacemaker implantation. Telephone interview was conducted to further confirm the number of first degree relatives (FDRs) with IPs.
Results: A total of 113 patients and 60 controls were recruited. Among the patients, 23 of them have at least one FDR with an IP (20.4%) and 4 had multiple FDRs (range 2-4) with IPs. In comparison, only 4 of the control patients (6.7%) have any FDRs with IP (p=0.03) and none had multiple FDRs with an IP. A pacemaker was implanted in 50 of the 113 patients for conduction disturbances alone. Of these 11 had a FDR with an IP (22%) as compared to 2.6% of the population prevalence (P <0.0001). Among 34 with sinus node dysfunction as the only indication for IP, 4 (12%) had a FDR with IP as compared to 2.6% of the population (p=0.004).
Conclusions: A significant number of patients with pacemakers reports familial aggregation of their disorder. The presence of familial aggregation is independent of the primary indication for pacemaker implantation. This finding supports an underlying genetic susceptibility in the etiology of SB in the general population.
- © 2010 by American Heart Association, Inc.