Transcatheter aortic valve implantation (TAVI) in patients with bicuspid aortic valve stenosis: systematic review and meta-analysis

Background: Transcatheter aortic valve implantation (TAVI) is a feasible interventional technique for severe aortic stenosis in patients who are deemed inoperable or at high surgical risk. There is limited evidence for the safety and efficacy of TAVI in patients with bicuspid aortic valves (BAV), the most common congenital valve abnormality. In many TAVI trials, patients with BAV have been contraindicated due to concerns surrounding abnormal valve geometry, leading to malfunction or malpositioning. A systematic review and meta-analysis was conducted in order to assess the current evidence and relative merits of TAVI in aortic stenosis patients with BAV. Method: From six electronic databases, seven articles including 149 BAV and 2096 non-BAV patients undergoing TAVI were analysed. Results: Between the BAV and no-BAV cohorts, there was no difference in 30-day mortality (8.3% vs 9.0%; P=0.68), post-TAVI mean peak gradients (weighted mean difference, 0.36. mmHg; P=0.55), moderate or severe paravalvular leak (25.7% vs 19.9%; P=0.29), pacemaker implantations (18.5% vs 27.9%; P=0.52), life-threatening bleeding (8.2% vs 13.9%; P=0.33), major bleeding (20% vs 16.8%; P=0.88), conversion to conventional surgery (1.9% vs 1.2%; P=0.18) and vascular complications (8.6% vs 10.1%; P=0.32). Conclusions: Preliminary short and mid-term pooled data from observation studies suggest that TAVI is feasible and safe in older patients with BAV. While future randomised trials are not likely, larger adequately-powered multi-institutional studies are warranted to assess the long-term durability and complications associated with TAVI in older BAV patients with severe aortic stenosis.