One-Year Mortality in Patients Undergoing Transcatheter Aortic Valve Replacement for Stenotic Bicuspid versus Tricuspid Aortic Valves: A Meta-Analysis and Meta-Regression

Objective. To assess 1-year mortality after transcatheter aortic valve replacement (TAVR) in patients with bicuspid aortic stenosis (AS). Background. Clinical trials have proven the beneficial effect of TAVR on mortality in patients with tricuspid AS. Individuals with bicuspid AS were excluded from these trials. Methods. A meta-analysis using literature search from the Cochrane, PubMed, ClinicalTrials, SCOPUS, and EMBASE databases was conducted to determine the effect of TAVR on 1-year mortality in patients with bicuspid AS. Short-term outcomes that could potentially impact one-year mortality were analyzed. Results. After evaluating 380 potential articles, 5 observational studies were selected. A total of 3890 patients treated with TAVR were included: 721 had bicuspid and 3,169 had tricuspid AS. No statistically significant difference between the baseline characteristics of the two groups of patients was seen outside of mean aortic gradient. Our primary endpoint of one-year all-cause mortality revealed 85 deaths in 719 patients (11.82%) with bicuspid AS compared to 467 deaths in 3100 patients (15.06%) with tricuspid AS, with no difference between both groups [relative risk (RR) 1.03; 95% CI 0.70-1.51]. Patients with bicuspid AS were associated with a decrease in device success (RR 0.62; 95% CI 0.45-0.84) and an increase in moderate-to-severe prosthetic valve regurgitation (RR 1.55; 95% CI 1.07-2.22) after TAVR compared to patients with tricuspid AS. The effect of meta-regression coefficients on one-year all-cause mortality was not statistically significant for any patient baseline characteristics. Conclusion. When comparing TAVR procedure in tricuspid AS versus bicuspid AS, there was no difference noted in one-year all-cause mortality.