Objective: The requirement for permanent pacemaker implantation after most initial cardiac surgical procedures generally is less than 3%. To identify the incidence and factors related to permanent pacemaker need after repeat cardiac surgery, we retrospectively studied 558 consecutive patients undergoing at least one repeat cardiac operation.
Method: Univariable and multivariable analyses of comorbidity, preoperative catheterization values, and operative data were performed to identify factors related to pacemaker implantation.
Results: In this group, 54 patients (9.7%) required a permanent pacemaker. A multivariable model showed a relationship between a permanent pacemaker and tricuspid valve replacement/annuloplasty associated with aortic/mitral valve replacement, preoperative endocarditis, increasing number of reoperations, the degree of hypothermia during cardiopulmonary bypass, and advanced age. Additional univariable predictors of pacemaker need included multiple valve replacement, increased cardiopulmonary bypass and aortic crossclamp times, and aortic valve replacement. Over 90% of patients who have or have not received permanent pacemaker implantation were in New York Heart Association class I to II, with a mean follow-up time of 6 years. Kaplan-Meier survival curves were statistically similar for both groups at 5 and 10 years after the operation.
Conclusion: Permanent pacemaker implantation was required in 9.7% of patients undergoing repeat cardiac surgery. This represented approximately a fourfold increase compared with similar primary operations reported in other series. Factors strongly related to this need included valve replacement, preoperative endocarditis, number of reoperations, advanced age, and degree of hypothermia during cardiopulmonary bypass. The need for a permanent pacemaker after reoperations did not result in significant long-term impairment of functional status or longevity compared with those who did not require a permanent pacemaker.