Stented Versus Stentless Aortic Valve Replacement in Patients With Small Aortic Root A Systematic Review and Meta-Analysis

Objective: The aim of the study was to compare hemodynamic and perioperative outcomes of stented against stentless aortic valve replacement in patients with small aortic root (21 mm or less). Methods: A comprehensive search was undertaken among the four major databases (PubMed, Embase, Scopus, and Ovid) to identify all randomized and nonrandomized controlled trials comparing stentless to stented bioprosthetic valves in small aortic root patients. Odds ratios, weighted mean differences, or standardized mean differences and their 95% confidence intervals were analyzed. Results: A total of seven studies with a total of 965 patients fulfilled the inclusion criteria. There was no significant difference in preoperative baselines including mean age between both groups (P = 0.08), peak aortic valve gradient (P = 0.06), and effective orifice area (P = 0.28), whereas higher mean aortic valve gradient in the stented group (P = 0.007). No difference in cardiopulmonary bypass time (P = 0.74), aortic cross-clamp times (P = 0.88), intensive care unit stay (P = 0.13), and stroke rate (P = 0.56) were noted. However, stented group of patients showed higher rate of patient prosthesis mismatch (P = 0.0001) and longer total hospital stay (P = 0.002). Postoperatively, stentless group showed lower peak and mean aortic valve gradient (P = 0.003 and P = 0.008, respectively) with a better effective orifice area (P < 0.00001) at 6 months of follow-up. Mortality rates while in-hospital and at 1 year were similar in both groups (P = 0.94 and P = 0.86, respectively). Conclusions: Stentless aortic valves offer superior short-term hemodynamic outcomes in patients with small aortic root when compared with stented aortic valves. Although both groups have similar perioperative complications rates, stentless valves bring about a shorter hospital stay. A further large multicenter randomized controlled trial should address the longer-term benefit of stentless aortic valve over stented valve.