Effect of Basal Septal Hypertrophy on TAVR Outcomes: Evidence From a Large Cohort Study

ABSTRACT Background Basal septal hypertrophy (BSH) is commonly encountered in elderly patients undergoing transcatheter aortic valve replacement (TAVR). However, its impact on periprocedural and procedural outcomes remains unclear. Aims The aim of this study was to evaluate the effect of BSH on periprocedural and postprocedural outcomes in patients undergoing TAVR. Methods This study included patients with severe aortic stenosis (AS) who underwent TAVR using either balloon‐expandable (BEVs) or self‐expanding valves (SEVs). The primary endpoint was to compare periprocedural interventions and procedural outcomes. Secondary endpoints included subgroup analyses by device generation (new vs. old), valve type (BEVs vs. SEVs), severity of septal hypertrophy, and across study periods. Results A total of 3261 TAVR patients were included: 1050 had a BSH ≥ 15 mm (HS+ group) and 2211 had a septal thickness < 15 mm (HS– group). Patients in the HS+ group had higher rates of post‐dilatation (25% vs. 21%, p = 0.008), moderate or greater paravalvular leak (PVL) on angiography (2.4% vs. 0.8%, p < 0.001) and echocardiography (5% vs. 3.4%, p = 0.033), and permanent pacemaker (PPM) implantation (18% vs. 14%, p = 0.008). Conversely, HS− patients more often required valve repositioning and a second valve. In subgroup analyses stratified by device generation, the influence of BSH appeared broadly consistent across platforms. Additional Subgroup analysis showed particularly higher rates of post‐dilatation, moderate or greater PVL, and PPM implantation in the SEV HS+ group, whereas mild septal thickening (12–15 mm) had no significant impact compared with marked hypertrophy (≥ 15 mm). Conclusion In this large cohort of TAVR patients, BSH (≥ 15 mm) was associated with higher rates of post‐dilatation, PVL, and PPM implantation, particularly among those receiving SEVs, while mild septal thickening had no significant impact.