Female sex is a risk factor for mortality after aortic valve replacement, for major vascular complications after TAVI, and for transfusions after both approaches.

Background-The proven efficacy of transcatheter aortic valve implantation (TAVI) in high-risk patients is leading to the expansion of its indications toward lower-risk patients. However, this shift is not supported by meaningful evidence of its benefit over surgical aortic valve replacement (SAVR). This analysis aims to describe outcomes of TAVI versus SAVR in low-risk patients. Methods and Results-We compared the outcome after TAVI and SAVR of low-risk patients (European System for CardiacOperative Risk Evaluation II [EuroSCORE II] <4%) included in the Observational Study of Effectiveness of SAVR-TAVI Procedures for Severe Aortic Stenosis Treatment (OBSERVANT) study. The primary outcome was 3-year survival. Secondary outcomes were early events and major adverse cardiac and cerebrovascular events at 3 years. Propensity score matching resulted in 355 pairs of patients with similar baseline characteristics. Thirty-day survival was 97.1% after SAVR and 97.4% after TAVI (P=0.82). Cardiac tamponade, permanent pacemaker implantation, major vascular damage, and moderate-to-severe paravalvular regurgitation were significantly more frequent after TAVI compared with SAVR. Stroke rates were equal in the study groups. SAVR was associated with higher risk of cardiogenic shock, severe bleeding, and acute kidney injury. At 3 years, survival was 83.4% after SAVR and 72.0% after TAVI (P=0.0015), whereas freedom from major adverse cardiac and cerebrovascular events was 80.9% after SAVR and 67.3% after TAVI (P<0.001). Conclusions-In patients with low operative risk, significantly better 3-year survival and freedom from major adverse cardiac and cerebrovascular events were observed after SAVR compared with TAVI. Further studies on new-generation valve prostheses are necessary before expanding indications of TAVI toward lower-risk patients. The aim of the present study is to evaluate the early and 3-year outcome after TAVI and SAVR in low-risk patients (EuroSCORE II <4%) from the multicenter nationwide prospective Observational Study of Effectiveness of SAVR-TAVI Procedures for Severe Aortic Stenosis Treatment (OBSERVANT) study. Methods Study Design and Data CollectionOBSERVANT is a national observational, prospective, multicenter, cohort study that enrolled consecutive patients undergoing TAVI or SAVR for severe aortic valve stenosis at 93 Italian cardiology/cardiac surgery centers between December 2010 and June 2012. Details on the study design, patient eligibility criteria, and data collection modalities have been reported elsewhere.9 This study was coordinated by the Italian National Institute of Health and led in cooperation with the Italian Ministry of Health, the National Agency for Regional Health Services, Italian Regions, and Italian scientific societies and federations representing Italian professionals involved in the management of aortic valve stenosis. The complete list of executive working group, participating centers, and investigators is reported in the Appendix in the Data Supplement. In the participating hospital...