Predictors of moderate-to-severe paravalvular aortic regurgitation immediately after CoreValve implantation and the impact of postdilatation

Objective: To investigate the predictors of moderate-to-severe aortic regurgitation (AR≥21) after CoreValve implantation and evaluate the feasibility and safety of postdilatation in reducing the degree of AR. Background: Although transcatheter aortic valve implantation is an alternative treatment for high surgical risk patients with severe aortic stenosis, post-implantation paravalvular AR remains a complication. Methods: From July 2008 to July 2010, we enrolled 79 consecutive patients with severe aortic stenosis who underwent CoreValve implantation. Results: On univariable analysis, the predictors of AR≥21 immediately after CoreValve implantation were: larger annulus size, low implantation, prosthesis mismatch, chronic renal insufficiency, a history of heart failure, and peripheral vascular disease. On multivariable analysis, the independent predictors of AR≥21 were: larger annulus diameter (OR 1.78, 95%CI 1.25-2.55; P 5 0.002), low implantation (OR 3.67, 95%CI 1.01-13.35, P 5 0.05), and peripheral vascular disease (OR 3.54, 95%CI 1.19-10.56, P 5 0.02). Post-CoreValve implantation, AR _ 2 was seen in 40.5% (32/79). Twenty-one patients underwent postdilatation with improvement in AR grade in the majority (17/21). Of the four patients who did not respond to postdilatation, two underwent valve-in-valve implantation. In one patient, the valve was pulled more proximally by the snare technique. The remaining 10 patients were treated conservatively. Conclusion: The appropriate strategy for treating patients with AR≥21 depends on the causes and severity of AR post-TAVI. This study suggests that we should carefully select the size of CoreValve prosthesis to prevent prosthesis mismatch, especially when implanted in larger annulus sizes. For valves implanted in the appropriate position, postdilatation appears effective in reducing the degree of AR.