Aortic Root Enlargement Is Safe and Reduces the Incidence of Patient-Prosthesis Mismatch: A Meta-analysis of Early and Late Outcomes

Background: Aortic root enlargement (ARE) may be an important adjunct to aortic valve replacement (AVR) to prevent patient-prosthesis mismatch and facilitate future valve-in-valve transcatheter AVR (TAVR). However, the early safety and late benefits of adding surgical ARE to AVR remain controversial. Methods: MEDLINE and EMBASE were searched from 1946 to 2018 for articles comparing patients undergoing AVR+ARE with those undergoing AVR alone. A random-effects meta-analysis was performed to compare early and late clinical outcomes. Results: A total of 2570 AVR+ARE and 5,991 AVR patients were included from 9 observational studies. There was no difference in early mortality (relative risk [RR] 1.21; 95% confidence interval [CI], 0.94-1.54; P = 0.13). Both cardiopulmonary bypass (mean difference [MD] 20 minutes; 95% CI, 15-25; P < 0.01) and aortic cross-clamp time (MD 14 minutes; 95% CI, 11-17, P < 0.01) were higher following AVR+ARE. There was no difference in the risk of permanent pacemaker implantation (RR 1.02; 95% CI, 0.83-1.25; P = 0.86), reoperation for bleeding (RR 1.05; 95% CI, 0.84-1.32; P = 0.64), or stroke (RR 0.93; 95% CI, 0.68-1.27; P = 0.65). The risk of moderate (indexed effective orifice area [iEOA] < 0.85 cm(2)/m(2)) and severe (iEOA < 0.65 cm(2)/m(2)) patient-prosthesis mismatch (PPM) was lower with AVR+ARE (RR 0.65; 95% CI, 0.51-0.83; P < 0.01) and RR 0.36; 95% CI, 0.16-0.82; P = 0.01, respectively). There was no difference in late mortality (incidence rate ratio [IRR] 1.05; 95% CI, 0.87-1.27; P = 0.59) at mean 7.8-year follow-up in 5 studies. Conclusions: Surgical ARE is a safe adjunct to AVR in selected patients that does not increase early adverse events and results in less patient-prosthesis mismatch. This strategy allows for a larger valve size at the time of implantation, an important consideration for potential future valve-in-valve procedures in the era of TAVR.