Relationship between membranous septum length and need for pacemaker implantation after transcatheter aortic valve implantation

To the Editor, Transcatheter aortic valve implantation (TAVI) can trigger significant conduction disorders due to the mechanical compression caused by the transcatheter heart valve. This is because of the proximity between the aortic annulus, the atrioventricular node, and the membranous septum (MS) of the left ventricular outflow tract. The rate of pacemaker implantation after TAVI ranges from 4% to 33%.1 This retrospective analytical study included symptomatic patients with severe aortic stenosis referred for multidetector computed tomography as part of the TAVI protocol from December 2012 through October 2022. Written informed consent was obtained from all patients prior to the tomography scan. We excluded patients with bicuspid aortic valve anatomy, pacemaker carriers, and those with biological bioprosthetic valves. The aim of this study was to determine whether MS length is associated with the need for pacemaker implantation after TAVI. MS length was measured as the maximum distance from the plane of the aortic annulus to the top of the muscular portion of the ventricular septum in the coronal plane during systole (figure 1A,B).2 Qualitative variables were analyzed using the chi-square test or Fisher exact test, while quantitative variables were analyzed using the Mann-Whitney U test. P values < .005 were considered statistically significant....