Prognostic Impact of Baseline Six-Minute Walk Distance following Trans-Catheter Aortic Valve Replacement

Abstract

Background: The six-minute walk test is a practical tool for assessing functional capacity in patients with a variety of etiologies including pulmonary disease and heart failure. Six-minute walk distance (6MWD) is associated with mortality and morbidity in patients with a variety of comorbidities. We aimed to assess the prognostic impact of baseline 6MWD in patients with severe aortic stenosis undergoing trans-catheter aortic valve replacement (TAVR). Methods: Patients with severe aortic stenosis who underwent a six-minute walk test after index admission and underwent TAVR between 2015 and 2022 were included in this retrospective study. Patients were followed up for two years or until November 2022 following TAVR. The impact of baseline 6MWD on the primary composite outcome, defined as all-cause death and all-cause readmission during the 2-year observation period following index discharge, was assessed. Results: A total of 299 patients (median age 86 years old, 85 men) were included. They received a 6-min walk test prior to TAVR, underwent successful TAVR procedures, and were discharged alive. The median baseline 6MWD was 204 (143, 282) meters. Shorter baseline 6MWD was associated with higher cumulative incidence of the primary outcome with an adjusted hazard ratio of 0.76 (95% confidence interval 0.58–1.01, p = 0.055) with a cutoff 6MWD of 178 m during the 2-year observation period after index discharge. Conclusions: Overall, functional capacity was impaired in the elderly patients with severe aortic stenosis prior to TAVR. Patients with severe aortic stenosis having shorter baseline 6MWD tended to have higher rates of morbidity and mortality after successful TAVR. The clinical implication of aggressive cardiac rehabilitation to improve patients’ functional capacity and 6MWD-guided optimal patient selection remain the future concerns.