Raising the Evidentiary Bar for Guideline Recommendations for TAVR JACC Review Topic of the Week

On August 16, 2019, the U.S. Food and Drug Administration approved expanding the indication for transcatheter aortic valve replacement (TAVR) to low-risk patients with symptomatic severe aortic stenosis. The decision was based on the results of 2 pivotal trials that confirmed superiority (PARTNER [Placement of Aortic Transcatheter Valves] 3) or noninferiority (Evolut Low Risk [LR]) of TAVR as compared with SAVR at 1- and 2-year follow-up, respectively. As compared with intermediate-risk cohorts, the sample size in these trials was smaller and the total number of primary endpoint events was nearly 3 times as low (193 vs. 615). The total number of deaths from any cause or disabling stroke at 1 year in the low-risk cohorts was 62, which is substantially lower than the numbers in intermediate-, high-, and inoperable-risk cohorts. In Evolut LR, only 137 of 1,403 patients (9.8%) completed the 2-year follow-up, with 91.2% requiring modelbased imputation. Thus, the quantum of evidence is insufficient for endorsing TAVR as the preferred intervention for these patients. (C) 2020 by the American College of Cardiology Foundation.