Evaluating Outcomes of Overexpanding Versus Conventional Sizing in Transcatheter Aortic Valve Replacement for Borderline Aortic Annulus: A Meta-Analysis.

Approximately 20%-40% of patients that present for transcatheter aortic valve replacement with a balloon-expandable transcatheter heart valve (THV) fall into a borderline aortic annulus size (BAAS). There are potential benefits to overexpanding an undersized THV (OE-THV) in such cases that include reduced electrical disturbances and annular injury at the expense of increased paravalvular leak (PVL). We conducted a meta-analysis of data comparing conventional-sized versus OE-THV strategy for BAAS and reviewed the literature for balloon-expandable-THV in such cases. 9 nonrandomized studies that compared a conventional strategy to OE-THV in patients with BAAS were included in our study. Our findings suggest that there is no difference in mortality, stroke, mean gradient, or significant PVL. There was a trend towards fewer pacemakers in patients receiving an OE-THV. Borderline aortic annulus measurements are common in patients undergoing transcatheter aortic valve replacement and there appears to be equipoise between conventional sizing versus OE-THV. Future detailed studies are required to evaluate short- and long-term outcomes among strategies.