Factors influencing prognosis of survival rate of patients with pacemakers

AIM To observe the long-term survival of patients with right ventricular pacing and to explore the risk factors that may affect the prognosis. METHODS A retrospective follow-up analysis was conducted in 1,245 patients implanted with permanent pacemaker from January 1991 to December 2010 for type II, degree II atrial-ventricular block, III degree atrial-ventricular block and auricular fibrillation with long interval and sick sinus syndrome such as slow cardiac arrhythmia. Follow-up data were continuously collected after pacemaker implantation until the endpoint. Survival rate was estimated using the Kaplan-Meier method and risk factors for mortality were sought using the multivariate Cox proportional hazards method. RESULTS The total survival rate during follow-up (3-23 years) was 91.3% and the survival rates at 5, 10, 15 and 20 years were, respectively, 92.9%, 88.9%, 81.9% and 75.1%. Single factor analysis showed that age, gender, pacemaker mode, chronic renal failure, ischemic cardiomyopathy and dilated cardiomyopathy (DCM) were the risk factors affecting the survival. Independent predictors of increased mortality were age at implant (hazard ratio, HR 1.987; 95% confidence interval, CI 1.587-2.489), DCM (HR 45.332; 95%CI 24.321-84.495) and ischemic cardiomyopathy (HR 8.418; 95%CI 3.605-19.65). CONCLUSION Implantation of permanent pacemaker prolongs the life of patients. Age at implant, ischemic cardiomyopathy and DCM are the independent risk factors for increased mortality.