Aortic valve replacement in patients with small aortic annuli: a systematic review and network meta-analysis

Up to 40% of patients with aortic stenosis undergoing valve replacement have a small annulus, a key determinant of valve hemodynamics, durability, and clinical outcomes. Surgical and transcatheter approaches have been reported to be determined by prosthesis design, considering the operative mortality and morbidity risk. The authors sought to evaluate surgical and transcatheter strategies in patients with small aortic annuli.

The authors systematically reviewed and synthesized evidence of 20 studies including 8843 patients. Primary outcomes included all-cause death and severe patient-prosthesis mismatch (PPM). Secondary outcomes included hemodynamic structural and non-structural valve dysfunction, postprocedural hemodynamics (indexed effective orifice area [iEOA] and mean transvalvular gradients), and major clinical events.

Compared with supra-annular self-expanding valves (SAV), intra-annular devices and surgical aortic valve replacement (SAVR) were associated with higher risks of severe PPM (P < .05) without differences in 1-year mortality (P > .05). Balloon-expandable valves were associated with increased hemodynamic structural dysfunction (risk ratio [RR], 4.44; 95% CI, 2.08-9.45), smaller iEOA (mean difference [MD], -0.18 cm²/m²; 95% CI, -0.24 - -0.11), and higher gradients (MD 4.72 mm Hg; 95% CI, 3.52-5.92). SAVR showed the worst hemodynamics, but lower risk of paravalvular leak (RR, 0.12; 95% CI; 0.03-0.54), pacemaker implantation (RR, 0.43; 95% CI; 0.20-0.94) and major vascular complications (RR, 0.20; 95% CI, 0.08-0.47). Stroke, major bleeding, and heart failure hospitalization events were similar among groups.

In patients with small annuli, SAV showed superior hemodynamic profile and the lowest risk of dysfunction. These differences did not translate into a lower incidence of hard clinical outcomes at 1-year follow-up.