Haemodynamic and safety outcomes of bioprosthetic valve fracture in VIV-TAVI: a systematic review and meta-analysis

Background Valve-in-valve transcatheter aortic valve replacement (VIV TAVR) for failed tissue valves in high risk patients can lead to suboptimal expansion in smaller valves with reported one year mortality up to 25% [1]. Bioprosthetic valve fracture (BVF) which uses high-pressure balloon inflation to fracture the surgical valve ring is used to allow for further expansion [2]. Whilst early data suggests improved haemodynamics, concerns have been raised regarding efficacy and safety outcomes. Aim This systematic review and meta-analysis aims to synthesise short and long term haemodynamic and safety outcomes following BVF in comparison to non-BVF. A rigorous synthesis was warranted to inform procedural planning and guidelines. Methods A comprehensive systematic search was conducted across MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials (CENTRAL). The primary haemodynamic endpoints were short and long-term mean transvalvular gradient and aortic valve area. The primary safety endpoints were 30 day and 1 year all cause mortality. Secondary outcomes included cardiovascular mortality, stroke, new pacemaker implantation, major bleeding and annular rupture. Adjusted comparative effect estimates were pooled using a random-effects meta-analysis with restricted maximum likelihood estimation. Results The search identified 499 studies with 16 studies meeting inclusion criteria. Meta-analysis revealed significant heterogeneity (I² = 63.84%) but demonstrated a reduction in the short term and a sustained reduction in the long term for mean gradient. The short-term pooled mean gradient was 29.12 (95% CI: 26.45-31.78) with substantial heterogeneity (I² = 63.84%), whilst the non-BVF cohort had a smaller reduction of 20.51 (95% CI: 19.24-21.78; I² = 52%). In the long term, the reduction in mean gradient was 26.49 (95% CI: 21.19-28.78). In the short term, the pooled mean difference in aortic valve area (AVA) was 0.59 (95% CI: 0.28–0.90; I² = 96.1%), while the non-BVF cohort had a similar change of 0.57 (95% CI: 0.50–0.63; I² = 79%). In this meta-analysis, the pooled incidence of 30-day all-cause mortality was 3% (95% CI 2%–4%) compared to 2.38% (95% CI 2%-3%) in the non-BVF cohort and 1 year mortality was 8% (95% CI 5-14%). Secondary outcomes included a pooled incidence of cardiovascular mortality 1% (95% CI 1-3%), stroke was 1% (95% CI 1%-3%), new pacemaker implantation was 2% (95% CI 2%-4%), major bleeding 3% (95% CI 2%-5%), annular rupture 1% (95% CI 1%-3%), with no observed heterogeneity across studies for any outcome (all I² = 0%, p = 1.00). Conclusion This study demonstrates that BVF significantly reduces transvalvular gradients and improves aortic valve area, with sustained haemodynamic benefit at longer-term follow-up. These findings support BVF as an effective adjunct to optimise valve expansion, with clinical outcomes suggesting an acceptable safety profile in appropriately selected patients.