Outcomes of Self-Expanding Versus Balloon-Expandable Transcatheter Aortic Valves in Patients With Reduced Left Ventricular Ejection Fraction: A Meta-Analysis of Observational Studies.

Patients with reduced left ventricular ejection fraction (LVEF) undergoing transcatheter aortic valve replacement remain a clinically vulnerable group. Although self-expanding valves (SEVs) and balloon-expandable valves are widely used, the optimal choice in patients with LVEF <40% remains uncertain. We aimed to synthesize the available evidence comparing these two valve types in this high-risk population. We conducted a systematic review and meta-analysis of observational studies comparing SEVs and balloon-expandable valves in patients with LVEF <40% undergoing transcatheter aortic valve replacement. Outcomes included changes in LVEF, aortic gradients, mortality, and safety endpoints. Pooled estimates were calculated using random-effects models, and multivariable meta-regression was performed to adjust for study-level confounding. Five studies comprising 5365 patients were included. SEVs were associated with a greater improvement in 1-month LVEF (mean difference, 2.33; 95% confidence interval [CI], 0.83 to 3.83; p = 0.01) and lower mean aortic gradients (mean difference, -2.72; 95% CI, -3.51 to -1.93; p < 0.01). Procedural mortality (risk ratio [RR], 0.89; 95% CI, 0.26-3.11; p = 0.86), 30-day mortality (RR, 1.52; 95% CI, 0.65-3.56; p = 0.33), and 1-year mortality (RR, 1.13; 95% CI, 0.69-1.84; p = 0.44) were similar. SEVs carried an increased risk of moderate or worse paravalvular leak (RR, 2.52; 95% CI, 1.46-4.36; p < 0.01). While SEVs may offer superior early LVEF improvement, they are associated with a higher rate of paravalvular leaks. Current data are observational and insufficient to recommend one valve type over another.