Bioprosthetic structural valve deterioration: How do TAVR and SAVR prostheses compare?

Abstract

Background: The durability of TAVR prostheses has come under major scrutiny since the move towards lower risk patients. We sought to compare the rate of structural valve deterioration (SVD) over time between transcatheter aortic valve replacement (TAVR) and surgical aortic valve replacement (SAVR).

Methods: We included all TAVR and SAVR patients (age ≥ 75 years) that were performed in our centre from 2005 until 2015. Applying the internationally "agreed on" definitions of SVD, we surveyed all available serial echocardiographic follow-ups.

Results: We included 269 TAVR and 174 SAVR cases. Post-intervention, TAVR patients had lower mean and peak gradients but higher rate of mild aortic regurgitation. SAVR patients had longer follow-up (in months, SAVR: 53 (30, 85) Vs TAVR: 33.4 (23, 52)). SVD as per Valve Academic Research Consortium-2 (VARC-2) was similar between the two groups (TAVR 28% Vs SAVR 31%; P = 0.593) but moderate haemodynamic SVD (European Association of Percutaneous Cardiovascular Intervention (EAPCI) criteria) was more common among SAVR cases (TAVR 11.5% Vs SAVR 20.7%; P = 0.007). Using Kaplan-Meier estimates, the rate of SVD over time was not different between the two groups as per VARC-2 criteria but different when moderate haemodynamic SVD criteria were applied (Log Rank P = 0.022) in favour of TAVR. The mean gradient rose steadily over time but more so post-SAVR (β = 0.52 ± 0.24 in comparison to TAVR at every given time point; P = 0.032).

Conclusion: Structural valve deterioration is common on long-term follow-up post-TAVR. The rate is similar to post-SAVR cases according to VARC-2 criteria but less according to the moderate haemodynamic SVD criteria.

Keywords: Aortic stenosis; Elderly (>75 years); Structural valve deterioration; TAVR; Valve-in-valve.