Factors predicting persistence of AV nodal block in post-TAVR patients following permanent pacemaker implantation.

Introduction A common complication of transcatheter aortic valve repair (TAVR) is development of conduction defects requiring pacemaker (PPM) implantation. These defects are not universally permanent. Objective To determine the incidence and predictors of persistent device dependency in patients with PPM implantation following TAVR with a self-expanding prosthesis. Methods Records of patients who underwent post-TAVR PPM implantation were reviewed. Patients with persistent complete AV block (AVBIII) one month post-TAVR were compared to those regaining conduction. Results Between September 2014 and March 2017, 485 patients underwent TAVR with a self-expanding prosthesis; 77 (15.9%) underwent PPM implantation for AVBIII. Device interrogation at one month was available for 61 patients (79%): 22 (36.1%) had resolution of AVBIII while 39 (63.9%) remained pacemaker-dependent. Pre-TAVR right bundle branch block was more frequent in device-dependent patients (19 of 38, 50% vs 4 of 22, 18%; RR 2.75; P = .01). Device-dependence was associated with AVBIII as the first postprocedural rhythm (37 of 39, 95% vs 12 of 22, 55%; RR 1.74; P < .0001), earlier implantation (median 1d, IQR: 0-1.5d vs 2d, IQR: 1.0-4.0d, P = .0004), and a shorter duration of hospitalization (median 3d, IQR: 2-3.5d vs 4d, IQR: 2-5.75d, P = .03). Pacemaker dependence was also associated with a higher prosthesis-to left ventricular outflow tract (LVOT) diameter (1.45 +/- 0.11 vs 1.39 +/- 0.07; P = .02) and the lack of prior aortic valvuloplasty (5 of 39, 13% vs 8 of 22, 36%; RR 0.35; P = .03). Conclusions In patients receiving a PPM following self-expanding TAVR, a long-term pacing requirement can be predicted from the timing of AV block, existing conduction-system disease, larger prosthesis-to-LVOT diameter, and the lack of aortic valvuloplasty.