Comparison of outcomes between TAVI and SAVR in patients with bicuspid aortic valve stenosis

Abstract Background Aortic valve stenosis may be treated surgically or percutaneously using transcatheter aortic valve implantation (TAVI). Objectives This study aimed to compare outcomes of patients with bicuspid valve aortic stenosis undergoing TAVI versus surgical aortic valve replacement (SAVR). Methods A retrospective cohort analysis of 581 patients with bicuspid aortic valve stenosis was conducted, of whom 71 (12%) underwent TAVI and 510 (88%) underwent SAVR. The mean age was 76±8 and 60±12 in the TAVI and SAVR groups, respectively. We excluded patients with pure aortic insufficiency. Due to age differences, we employed a matched model and subsequently conducted a multivariate Cox regression analysis with adjustment for mortality predictors and baseline characteristics. Using this model, we investigated the association between the procedure conducted and overall survival, as well as post-procedural clinical outcomes. Results Overall, 125 patients died during a mean follow-up period of 9±4 years. Of these, 24 were in the TAVI group and 101 were in the SAVR group. The study demonstrated that patients with bicuspid aortic valve stenosis undergoing TAVI are more likely to die compared with SAVR HR=6.4, 95% CI 3.9-10.4, p0.001 (figure 1A). Fifty patients developed life-threatening conduction abnormalities that necessitated pacemaker implantation; 20 (28%) patients in the TAVI group and 30 (6%) patients in the SAVR group, OR=8.2, 95% CI 3.1-21.7, p0.001 (figure 1B). Patients in the TAVI group suffered from increased rates of paravalvular leaks; OR=7.2, 95% CI 2.8-18.5, p0.001, and heart failure hospitalisations; incidence rate ratio=7.9, 95% CI 5.7-10.9, p0.001. There was no meaningful difference in stroke/TIA rates between the groups (figure 1C). To overcome the differences between the groups, we applied a 1:1 match according to patients’ age. The matched model demonstrated consistent results with an increased mortality rate (HR=2.3, 95% CI 1.3-4.3, p=0.005) and elevated rates of pacemaker implantation in the TAVI group (OR=5.5, 95% CI 2.1-14.4, p=0.005). We have demonstrated consistent results after adjusting the model for baseline characteristics and mortality predictors; mortality HR=2.8, 95% CI 1.2-6.5, p=0.02, pacemaker implantation OR=5.8, 95% CI 1.6-21.2, p=0.008. The matched model also demonstrated an elevated risk for heart failure hospitalisations; incident risk ratio 3.2, (95% CI 2.1-4.9, p0.001), and no meaningful differences in stroke/TIA rates (figure 2). Conclusions Patients with bicuspid aortic valve stenosis had better outcomes when undergoing SAVR compared to TAVI, albeit with no difference in stroke/TIA rates. Further research in the form of a randomised controlled trial is required in order to better understand the differences between a surgical approach and a transcatheter approach.Figure 1.Survival, pacemaker and stroke Figure 2.Multivariate endpoints