Stented vs. stentless in aortic stenosis: a systematic review and meta-analysis

Abstract

BACKGROUND: Symptomatic aortic stenosis (AS) is often treated surgically with aortic valve replacement using stented or stentless prostheses. While stentless valves offer potential hemodynamic benefits, a robust synthesis of the evidence regarding clinical outcomes is needed. This systematic review and meta-analysis assessed the effectiveness and safety of both valve types. METHODS: This study followed the PRISMA guidelines and was prospectively registered in PROSPERO (CRD42025636952). We systematically searched PubMed, Cochrane Library, Scopus, and Web of Science up to December 2024, with a search update in May 2025. We included both randomized and non-randomized studies. The outcomes were early and overall mortality rates, stroke, pacemaker implantation, endocarditis, postoperative atrial fibrillation, total reoperation, severe prosthesis-patient mismatch, hospital stay, cardiopulmonary bypass time, cross-clamp time, and hemodynamic parameters, including postoperative mean aortic valve gradient, left ventricular mass and left ventricular mass index, and left ventricular ejection fraction. A random-effects model with odds ratios (ORs) and mean differences (MDs) was employed. RESULTS: After screening 1,385 records, 20 studies were included, involving 3,940 participants with AS. Studies were first analyzed by design (randomized and non-randomized), and then pooled. There were no significant differences in all-cause mortality rates either early (OR = 1.04, 95% CI: [0.65 to 1.68], p = 0.861) or overall mortality at 1 year (OR = 0.86, 95% CI: [0.28 to 2.63], p = 0.797) and beyond 1 year (OR = 0.95, 95% CI: [0.62 to 1.46], p = 0.820). Postoperative complications showed comparable results between groups, except for pacemaker implantation, which was significantly increased in stentless valves (OR = 1.82, 95% CI: [1.14 to 2.92], p = 0.013). Hemodynamic outcomes showed no significant differences between groups. CONCLUSION: Our study revealed that the rates of early and overall mortality, postoperative complications, and hemodynamic parameters were comparable between stented and stentless valve groups. However, patients receiving stentless valves exhibited a significantly higher incidence of pacemaker implantation.