Pacemaker implantation associated with tricuspid repair in the setting of mitral valve surgery: Insights from a Cardiothoracic Surgical Trials Network randomized trial

Objectives: In a recent trial, tricuspid annuloplasty (TA) during mitral valve surgery (MVS) for degenerative mitral regurgitation and moderate or less tricuspid regurgitation (TR) reduced the composite rate of death, reoperation for TR, or TR progression at 2 years. However, this benefit was counterbalanced by an increase in implantation of permanent pacemakers (PPMs). In this study, we analyzed the timing, indications, and risk factors for these implantations. Methods: We randomized 401 patients (MVS alone = 203; MVS + TA = 198). Potential risk factors for PPMs were assessed using multivariable time-to-event models with death and PPM implantation for heart failure indications as competing risks. Results: A PPM was implanted in 36 patients (9.6; 95% CI, 6.8-13.0) within 2 years of randomization, with 30/187 (16.0%) in the MVS + TA and 6/188 (3.2%) in the MVS groups (rate ratio, 5.08; 95% CI, 2.16-11.94; P < .001). Most (29/36; 80.6%) implantations occurred within 30 days postoperatively. Independent risk factors for PPM implantation within 2 years were TA (hazard ratio [HR], 5.94; 95% CI, 2.27-15.53; P < .001), increasing age (5 years, HR, 1.23; 95% CI, 1.01-1.52; P = .04), and left ventricular ejection fraction (LVEF; HR, 0.96; 95% CI, 0.92-0.99; P = .02). In the subset of TA recipients (n = 197), age (5 years, HR, 1.05; 95% CI, 1.00-1.10; P = .04) and LVEF (HR, 0.95; 95% CI, 0.91-0.99; P = .01) were associated with PPM within 2 years. Conclusions: Concomitant TA, age, and baseline LVEF were risk factors for PPM implantation in patients who underwent MVS for degenerative mitral regurgitation. Although TA was effective in preventing progression of TR, innovation is needed to identify ways to decrease PPM implantation rates.