Echocardiographic Results of Transcatheter Versus Surgical Aortic Valve Replacement in Low-Risk Patients

Abstract

Background: The objective of this study is to compare echocardiographic findings in low risk patients with severe aortic stenosis (AS) following surgical (SAVR) or transcatheter aortic valve replacement (TAVR). Methods: The Placement of Aortic Transcatheter Valves 3 (PARTNER 3) trial randomized 1000 patients with severe AS and low surgical risk to undergo either transfemoral TAVR with the balloon-expandable SAPIEN 3 valve or SAVR. Transthoracic echocardiograms obtained at baseline, and at 30 days and 1 year post-procedure were analyzed by a consortium of 2 echocardiography core laboratories. Results: The percentage of moderate/severe aortic regurgitation (AR) was low and not statistically different between TAVR vs. SAVR groups (30 days: 0.8% vs. 0.2%; p=0.38). However, mild AR was more frequent following TAVR vs. SAVR (30 days: 28.8% vs. 4.2 %; p2; p=0.12) were similar in TAVR vs. SAVR. The percentage of severe prosthesis-patient mismatch (PPM) at 30 days was low and similar between TAVR and SAVR (4.6 vs. 6.3%, p=0.30). Valvulo-arterial impedance (Z_va), which reflects total left ventricular hemodynamic burden, was lower with TAVR vs. SAVR at 1 year (3.7±0.8 vs. 3.9±0.9 mmHg/mL/m² ; pva and low TAPSE, but not moderate/severe AR or severe PPM, were associated with increased risk of the composite endpoint of mortality, stroke and re-hospitalization at 1 year. Conclusions: In patients with severe AS and low surgical risk, TAVR with the SAPIEN 3 valve was associated with similar percentage of moderate/severe AR compared with SAVR, but higher percentage of mild AR. Transprosthetic gradients, valve areas, percentage of severe PPM, and LV mass regression were similar in TAVR versus SAVR. SAVR was associated with significant deterioration of RV systolic function and greater tricuspid regurgitation, which persisted at 1 year. High Zva and low TAPSE were associated with worse outcome at 1 year whereas AR or severe PPM were not. Clinical Trial Registration: URL: https://clinicaltrials.gov Unique Identifier: NCT02675114