Prognostic value of 6-minute walk corridor test in patients with mild to moderate heart failure: comparison with other methods of functional evaluation

Abstract

Aim: The study was designed to evaluate the prognostic value of the 6-min walk test (6MWT) in patients with mild to moderate congestive heart failure (CHF).

Methods and results: Two hundred and fourteen patients (119 men and 95 women, mean age 64 years) were followed for a mean period of 34 months to assess event-free survival (death, heart transplantation). Sixty-six patients (34%) died (63 cardiovascular causes, 2 cancer and 1 stroke) and five patients underwent heart transplantation. For patients who walked <300 m during the 6MWT, survival was 62% compared with 82% in patients who walked 300-450 m or>450 m. With univariate analysis, NYHA class was the strongest predictor of death. LVEF (P<0.0001), aetiology of heart failure (P<0.001), LV filling pattern (P=0.002) and 6MWT distance (P<0.01) were all significantly related to survival. No significant relationship was found between survival, peak oxygen consumption or anaerobic threshold. Multivariate analysis using the Cox-stepwise regression model showed that LV fractional shortening (P<0.009) and 6MWT distance (P<0.0005) were the strongest prognostic markers.

Conclusion: A 6MWT distance of <300 m is a simple and useful prognostic marker of subsequent cardiac death in unselected patients with mild to moderate CHF.