Transcatheter Aortic-Valve Replacement for Asymptomatic Severe Aortic Stenosis

BACKGROUND: For patients with asymptomatic severe aortic stenosis and preserved left ventricular ejection fraction, current guidelines recommend routine clinical surveillance every 6 to 12 months. Data from randomized trials examining whether early intervention with transcatheter aortic-valve replacement (TAVR) will improve outcomes in these patients are lacking. METHODS: At 75 centers in the United States and Canada, we randomly assigned, in a 1:1 ratio, patients with asymptomatic severe aortic stenosis to undergo early TAVR with transfemoral placement of a balloon-expandable valve or clinical surveillance. The primary end point was a composite of death, stroke, or unplanned hospitalization for cardiovascular causes. Superiority testing was performed in the intention-to-treat population. RESULTS: A total of 901 patients underwent randomization; 455 patients were assigned to TAVR and 446 to clinical surveillance. The mean age of the patients was 75.8 years, the mean Society of Thoracic Surgeons Predicted Risk of Mortality score was 1.8% (on a scale from 0 to 100%, with higher scores indicating a greater risk of death within 30 days after surgery), and 83.6% of patients were at low surgical risk. A primary end-point event occurred in 122 patients (26.8%) in the TAVR group and in 202 patients (45.3%) in the clinical surveillance group (hazard ratio, 0.50; 95% confidence interval, 0.40 to 0.63; P<0.001). Death occurred in 8.4% of the patients assigned to TAVR and in 9.2% of the patients assigned to clinical surveillance, stroke occurred in 4.2% and 6.7%, respectively, and unplanned hospitalization for cardiovascular causes occurred in 20.9% and 41.7%. During a median follow-up of 3.8 years, 87.0% of patients in the clinical surveillance group underwent aortic-valve replacement. There were no apparent differences in procedure-related adverse events between patients in the TAVR group and those in the clinical surveillance group who underwent aortic-valve replacement. CONCLUSIONS: Among patients with asymptomatic severe aortic stenosis, a strategy of early TAVR was superior to clinical surveillance in reducing the incidence of death, stroke, or unplanned hospitalization for cardiovascular causes. (Funded by Edwards Lifesciences; EARLY TAVR ClinicalTrials.gov number, NCT03042104.).