BAlloon expandable vs. SElf expanding transcatheter vaLve for degenerated bioprosthesIs: design and rationale of the BASELINE trial

Background: Surgical aortic valve bioprostheses may degenerate over time and require redo intervention. Transcatheter aortic valve replacement (TAVR) is a less invasive alternative to redo surgery. The BAlloon Expandable vs. SElf Expanding Transcatheter VaLve for Degenerated BioprosthesIs (BASELINE) trial was designed to compare the performance of the balloon-expandable SAPIEN-3 Ultra and the self-expanding EVOLUT PRO+ valve systems in symptomatic patients with a failing surgical bioprosthesis. Methods: The BASELINE trial is an investigator-initiated, non-funded, prospective, randomized, open-label, superiority trial enrolling a total of 440 patients in up to 50 sites in 12 countries in Europe and North-America. The primary endpoint is device success at 30-days defined by the Valve Academic Research Consortium-3 Criteria as the composite of technical success, freedom from mortality, freedom for surgery or intervention related to the device or to a major vascular or access-related or cardiac structural complication with an intended performance of the valve (mean gradient <20 mmHg and less than moderate aortic regurgitation). The co-primary endpoint at 1 year is defined as the composite of all-cause death, disabling stroke, rehospitalization for heart failure or valve related problems. Independent Core Laboratories will conduct uniform analyses of echocardiography (pre-, post-, 1-year post-procedure), multi-sliced computed tomography (pre-, and if available post-procedure) and cine-fluoroscopy studies. Conclusions: The BASELINE trial is a head-to-head comparative trial investigating the 2 most used contemporary transcatheter heart valves for the treatment of a failing surgical aortic bioprosthesis. (ClinicalTrials.gov number NCT04843072).