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

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.

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.

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.

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.