The role of valve-in-valve TAVR for the treatment of failing bioprosthetic aortic valve

Background
Currently TAVR is indicated for high and moderate –risk patients with severe symptomatic AS. Other indications are under investigation and that includes low-risk patients, aortic regurgitation and valve-in-valve. Currently, there is a paucity of data directly comparing the use of TAVR for degenerated bioprosthetic aortic valve compared to re-do aortic surgery. We did a meta-analysis comparing clinical and procedural outcomes between them.

Methods
Pub Med and Cochrane databases were systematically searched for clinical studies directly comparing clinical and procedural outcomes of patients with severe symptomatic degenerated bioprosthetc aortic valve treated with TAVR or re-do surgery. Primary outcomes included 30 days and one year mortality. Secondary outcomes included CVA, major bleeding, AKI and pacemaker implant. We used fixed (I² < 55%) otherwise random effect analysis using the Cochrane Handbook of Systematic Reviews.

Results
A total of seven studies provided 739 patients (381 in the TAVR and 358 SAVR group). Baseline characteristics showed majority of patients were men older than 60 years. Mean aortic valve gradient was 42±8 mmHg and peak velocity of 4.1±2 m/sec. Mean age of the valve implant was 8±4 years. Primary outcomes showed no difference in 30 day mortality (7.3% vs. 6.1%, p=0.55) and one year mortality (16% vs. 13%, p=0.47). Secondary outcomes showed significant less acute kidney injury in the TAVR group (6% vs. 12%, p<0.05). There were no differences in 30 days stroke, pacemaker implantation and major bleeding rates.

Conclusions
TAVR indications continue to evolve and certainly other aortic valve pathologies will benefit of them. Our analysis suggested that TAVR might be a safe and feasible procedure for the treatment of failed bioprosthetic aortic valve. In-deep analysis and further RCT’s will provide short and long-term benefits.