Relation of Prolonged Pacemaker Dependency After Cardiac Surgery to Mortality.

Permanent pacemaker implantation (PPI) represents a rare complication after cardiac surgery, with no uniform agreement on timing and no information on follow-up. A multicenter retrospective study was designed to assess pacemaker dependency (PMD) and long-term mortality after cardiac surgery procedures. Between 2004 and 2016, PPI-patients from 18 centers were followed. Time-to-event data were evaluated with semiparametric regression Cox models and semiparametric Fine and Gray model for competing risk framework. Of 859 (0.90%) PPI-patients, 30% were pacemaker independent (PMI) at 6 months. PMD showed higher mortality compared with PMI (10-year survival 80.1% ± 2.6% and 92.2% +2.4%, respectively, log-rank p-value < 0.001) with an unadjusted hazard ratio for death of 0.36 (95% CI 0.20 to 0.65, p< 0.001 favoring PMI) and an adjusted hazard ratio of 0.19 (95% CI 0.08 to 0.45, p< 0.001 with PMD as reference). Crude cumulative incidence function of restored PMI rhythm at follow-up at 6 months, 1 year and 12 years were 30.5% (95% CI 27.3% to 33.7%), 33.7% (95% CI 30.4% to 36.9%) and 37.2% (95% CI 33.8% to 40.6%) respectively. PMI was favored by preoperative sinus rhythm with normal conduction (SR) (HR 2.37, 95% CI 1.65 to 3.40, p< 0.001), whereas coronary artery bypass grafting and aortic valve replacement were independently associated with PMD (HR 0.63, 95% CI 0.45 to 0.88, p = 0.006 and HR 0.807, 95% CI 0.65 to 0.99, p = 0.047 respectively). Time-to-implantation was not associated with increased rate of PMI. Although 30% of PPI-patients are PMI after 6 months, PMD is associated with higher mortality at long term.
Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relations that could have appeared to influence the work reported in this study.
(Copyright © 2020 The Author(s). Published by Elsevier Inc. All rights reserved.)