Why is this study important? 

• Aortic stenosis is common, affecting 3% of adults 65 years of age and older. Untreated severe aortic stenosis is associated with increased mortality and reduced quality of life.
• Current guidelines give a Class I indication for aortic valve replacement in patients with symptomatic, severe aortic stenosis as well as severe aortic stenosis with an ejection fraction < 50% or a positive stress test. Guidelines recommend routine 6- to-12 month follow-up for patients with asymptomatic, severe aortic stenosis. 
• Limited data involving several small trials have demonstrated improved outcomes in surgical aortic valve replacement (SAVR) in asymptomatic patients with severe aortic stenosis, but currently no such data exist for transcatheter aortic valve replacement (TAVR) in asymptomatic, severe aortic stenosis.
• This study is the first prospective, multicenter, randomized, controlled trial to challenge current approaches to guideline management of asymptomatic, severe aortic stenosis with use of early TAVR. 

What question was this study supposed to answer? 

• The EARLY TAVR trial seeks to answer whether early intervention with transfemoral, ballon expandible TAVR in asymptomatic patients with severe aortic stenosis will improve outcomes, defined as a reduction in a composite endpoint of all-cause mortality, any stroke, or unplanned cardiovascular hospitalization, as compared to clinical surveillance which is recommended by current guidelines. 
• Secondarily, the EARLY TAVR trial seeks to determine whether TAVR in asymptomatic patients with severe aortic stenosis will prevent clinically meaningful reduction in quality of life and improve left ventricular/left atrial health. 

What did the study show? 

• At a median follow-up of 3.8 years, TAVR in asymptomatic, severe aortic stenosis patients resulted in a 50% (45.3% vs 26.8%, hazard ratio, 0.50;95% confidence interval [CI], 0.40 to 0.63; P<0.001) reduction in the composite primary endpoint driven primarily by reduction in unplanned cardiovascular hospitalizations. The number needed to treat (NNT) at 2 years is 6.
• All prespecified subgroups experienced consistent benefits of the early TAVR strategy as compared to clinical surveillance. 
• Early TAVR also prevented a decline in quality of life and improved indices of left ventricular/left atrial health.
• TAVR in asymptomatic, severe aortic stenosis patients demonstrated an excellent safety profile and was not associated with increased risk of stroke or mortality.