Survival predictors after pacemaker implantation in a very elderly population

Abstract Background Electrophysiological studies and ablation procedures are the most prevalent activities in electrophysiology. However, device implantation represents a great deal of the daily activity. In several European regions, aging populations are becoming a big concern, not only increasing the number of pacemakers implantations but also raising the age threshold for implantation. Purpose Assessment of survival rates after device implantations on patients over ninety years of age. Are there any markers that could help us infer survival rates? How prevalent are complications? What key performance indicators should be paying attention to? Methods Observational retrospective study of a cohort of 903 patients referred to the arrhythmia unit of our institution for pacemaker implantation, during the period from 2016 to 2019. Cox regression analysis performed over that cohort. Hazard-ratio (HR) and confidence intervals (CI 95%)calculated. Survival curves represented with Kaplan-Meier method and statistical significance estimated with log-rank test. Results Out of the 903 patients, 82 (9.1%) are nonagenarians. Follow-up was 3.97 ± 4.98 years. The mean age at the time of pacemaker implantation was 78.94 ± 10.11 years. Some complications were observed in 9.9% of patients under 90 years of age, compared to 4.9% in those over that age. At the time of the follow-up, 82.5% of the patients were alive. In the univariate analysis, the following predictors of mortality were identified: age; atrial fibrillation (AF); renal function; anemia; comorbidity, estimated by Charlson score; underlying heart disease; type of pacemaker implanted; and, whether the patient was institutionalized. In the multivariate analysis, the following were independent predictors of mortality: age (HR 1.129; 95% CI 1.1-1.159; p0.001), comorbidity reflected as a Charlson score ≥ 5 (HR 4.116; 95% CI 2.349 -7.212; p0.001); heart disease (HR 2.496; 95% CI 1.725-3.612; p0.001); institutionalization of the patient (HR 2.794; 95% CI 1.632-4.783; p0.001); and the single-chamber pacemaker (HR 2.201; 95% CI 1.455-3.329; p0.001). In the group of nonagenarian patients, the univariate analysis showed the following variables as predictors of lower survival: age; serum creatinine; comorbidity, estimated by the Charlson score; and, underlying heart disease. In the multivariate analysis, the following were identified as independent predictors of mortality: comorbidity, reflected as a Charlson score ≥ 5 (HR 7.299; 95% CI 2.468-21.589; p0.001); age (HR: 1.193; 95% CI 1.063- 1.339; p 0.003) and institutionalization of the patient (HR 3.033; 95% CI 1.237- 7.439; p 0.015). Conclusions Comorbility estimated by Charlson score is the most powerful survival predictor after pacemaker implantation, both in the general population and in those over 90 years of age. Being institutionalized is an independent survival predictor in both groups. Nonagenarian patients do not show a higher complication rate.Baseline characteristics 90 y.o.Survival curves K-M