Off-label use of balloon-expandable transcatheter valves to treat pure aortic regurgitation

Background Transcatheter aortic valve implantation (TAVI) in pure severe aortic regurgitation (AR) is challenging, as dedicated devices are not widely available. Off-label use of transcatheter heart valves (THVs) approved for the treatment of aortic stenosis has been reported. When balloon-expandable valves (BEV) are preferred, oversizing with respect to the annulus is necessary, but there is scant data regarding optimal oversizing. The study assesses BEV oversizing and outcomes of TAVI with BEV in pure AR. Methods Consecutive patients undergoing transfemoral TAVI in pure AR with Sapien BEV at our centre between 2019 and 2023 were included. Bicuspid (BAV) and tricuspid (TAV) aortic valves were analyzed separately. The aim was to implant a valve with 20-30% oversizing with respect to the annulus. TAV were divided into small annulus group (≤618mm2, SA) where ≥20% oversizing is achievable based on published data on BEV overexpansion and larger annulus group (LA, >618mm2). Overexpansion and oversizing were measured on post-procedural CT. Procedural and clinical outcomes were analyzed using the VARC-3 criteria. Results Seventeen patients were identified (76.5% males, mean age 79.2 years, STS 3.8%, TAV 13 patients). Mean aortic valvular calcium volume was: TAV=15.4mm3 and BAV=171.0mm3 (p=0.001). Technical success was 94.1% with one valve embolisation in TAV LA group. Mild paravalvular leak (PVL) was more frequent in BAV (p=0.0088). The post-procedural CT in TAV patients showed a mean 28.3% oversizing, significantly higher in SA (31.2%) then in LA group (19.4%), p= 0.0092. Oversizing ≥20% was achieved in 100% SA vs 33.3% LA patients (p=0.046). In LA patients the implanted BEVs were significantly more overexpanded than in SA group (10.8% vs 22.3%, p=0.0119) In-hospital mortality was 5.9%. There was no difference in 1-year mortality between groups. Conclusions TAVI in pure AR with oversized Sapien BEV showed good procedural and short-term outcomes when ≥20% oversizing was predictably achievable.