Pacemaker implantation after concomitant tricuspid valve repair in patients undergoing minimally invasive mitral valve surgery: Results from the Mini-Mitral International Registry

Objective: Randomized evidence suggests a high risk of pacemaker implantation for patients undergoing mitral valve (MV) surgery with concomitant tricuspid valve repair (cTVR). We investigated the impact of cTVR on outcomes in the Mini-Mitral International Registry. Methods: From 2015 to 2021, 7513 patients underwent minimally invasive MV with or without cTVR in 17 international centers (MV: n = 5609, cTVR: n = 1113). Propensity matching generated 1110 well-balanced pairs. Multivariable analysis was applied. Results: Patients with cTVR were older and had more comorbidities. Propensity matching eliminated most differences except for more TR in patients who underwent cTVR (77.2% vs 22.1% MV, P < .001). Mean matched age was 71 years, and 45% were male. European System for Cardiac Operative Risk Evaluation II was still 2.68% (interquartile range [IQR], 0.80-2.63) vs 1.9% (IQR, 1.12-3.9) in matched MV (P < .001). MV replacement (30%) and atrial fibrillation surgery (32%) were similar in both groups. Cardiopulmonary bypass (161 minutes [IQR, 133-203] vs MV: 130 minutes [IQR, 103-166]; P < .001) and crossclamp times (93 minutes [IQR, 66-123] vs MV: 83 minutes [IQR, 64-107]; P < .001) were longer with cTVR. Although in-hospital mortality was similar (cTVR: 3.3% vs MV: 2.2%; P = .5), postoperative pacemaker implantations (9% vs MV: 5.8%; P = .02), low cardiac output syndrome (7.7% vs MV: 4.4%; P = .02), and acute kidney injury (13.8% vs MV: 10%; P = .01) were more frequent with cTVR. cTVR eliminated relevant TR in most patients (greater-than-moderate TR: 6.8%). Multivariable analysis identified MV replacement, atrial fibrillation, and cTVR as risk factors of postoperative pacemaker implantation. Conclusions: cTVR in minimally invasive MV surgery is an independent risk factor for pacemaker implantation in this international registry. It is also associated with more bleeding, low output syndrome, and acute kidney injury. It remains unclear whether technical or patient factors (or both) explain these differences.