Evaluation of Conduction Disorders after Aortic Valve Replacement with Rapid Deployment Bioprostheses

OBJECTIVE: The aim of this retrospective, single-center study was to evaluate the occurrence of conduction disorders after rapid deployment aortic bioprosthesis implantation. METHODS: Electrocardiograms of patients undergoing INTUITY (Edwards Lifesciences, Irvine, CA USA) bioprosthesis implantation were collected at admission, during postoperative course, and at discharge. Primary end point was the occurrence of new-onset conduction disorders, defined as complete left bundle branch block, complete right bundle branch block, permanent pacemaker implantation, and worsening of pre-existing rhythm abnormalities. Secondary end points were the assessment of preoperative and postoperative QRS duration and the identification of transitory conduction disorders. RESULTS: Forty-four patients (July 2015-December 2016) were included in the analysis. Preoperatively, patients with normal conduction and with already existing disorders were 25 (56.8%) and 19 (43.2%), respectively. Primary end point occurred in 14 patients (31.8%). Two patients (4.5%) received pacemaker implantation. In patients with normal preoperative conduction, new abnormalities were found in eight cases (32%): all left bundle branch blocks with one pacemaker implantation. Worsening of pre-existing conduction disorders was found in six patients (31.6%) with one pacemaker implantation. QRS duration increased in 20 patients (45.4%), and average increase was 37 milliseconds. Overall, we observed a significant increase of QRS (96 ± 21 milliseconds vs. 111 ± 28 milliseconds, P < 0.001). Three patients experienced a new-onset temporary left bundle branch block. CONCLUSIONS: New-onset conduction disorders or worsening of pre-existing rhythm abnormalities occur in one third of patients after rapid deployment aortic bioprosthesis implantation. Although the incidence of postoperative pacemaker implantation before discharge is low, strict follow-up is mandatory to identify a potential need for pacemaker implantation in a timely manner.