Incremental shuttle and six-minute walking tests in the assessment of functional capacity in chronic heart failure

Background The incremental shuttle test presents some theoretical advantages over the six-minute walk test in chronic heart failure (CHF), including better standardization and less dependency on collaboration. Objectives The present study evaluated test-retest repeatability, test accuracy in predicting a peak oxygen consumption (VO 2 ) of 14mL/kg/min or less, as well as the prognostic value of both walking tests in stable CHF patients. Methods Sixty-three patients (44 men; New York Heart Association functional class II to IV) underwent an incremental treadmill exercise test and, on another day, the walk test in duplicate. Results Patients showed well-preserved functional capacity according to the distance walked in both tests (six-minute walk test 491±94m versus incremental shuttle walk test 422±119m; P 2 , but not distance walked in either test, was associated with survival (P Conclusions The incremental shuttle walk test showed similar repeatability and accuracy in estimating peak VO 2 compared with the sixminute walk test in CHF patients. Direct measurement of peak VO 2 , however, remains superior to either walking test in predicting survival – at least in patients with well-preserved functional capacity.