Prognostic Value of the 6-Minute Walk Test in Patients With Severe Aortic Stenosis

Abstract

Background: The prognostic significance of the 6-minute walk distance (6MWD) in patients with severe aortic stenosis (AS) has not been thoroughly investigated.

Methods and Results: This study evaluated 998 patients with severe AS who underwent a 6-min walk test as part of a large multicenter prospective cohort. Patients were categorized as either fast walkers (6MWD ≥300 m; n=515) or slow walkers (6MWD <300 m; n=483). During a median follow-up of 2.3 years, 861 (86.3%) patients underwent surgical or transcatheter aortic valve replacement (AVR; 87.0% of fast walkers vs. 85.5% of slow walkers). The cumulative 3-year incidence of death was significantly lower among fast walkers than slow walkers (10.9% vs. 31.7%; P<0.001). After adjusting for confounders, slow walkers had a significantly higher risk of all-cause mortality than fast walkers (hazard ratio 2.36; 95% confidence interval 1.55–3.58; P<0.001). Stratified analysis by initial treatment strategy revealed that the cumulative 3-year incidence of all-cause death was consistently lower among fast walkers than slow walkers (initial AVR strategy: 10.1% vs. 28.1% [P<0.001]; conservative strategy: 13.4% vs. 46.7% [P<0.001]). Among asymptomatic patients managed conservatively, fast walkers demonstrated a remarkably low cumulative 3-year incidence of all-cause death (8.1%).

Conclusions: The 6MWD is a reliable prognostic marker for patients with severe AS, regardless of initial treatment strategy.