Establishment of exercise intensity for patients with chronic heart failure equivalent to anaerobic threshold based on 6-minute walking test.

BACKGROUND

The study aimed to investigate the relationship between the aerobic exercise intensity determined by 6-minute walking distance (6MWD) and its counterpart based on anaerobic threshold (AT) in chronic heart failure (CHF) individuals for exploring suitable means for CHF exercise rehabilitation.

METHODS

We retrospectively analyzed data in patient with CHF, who performed cardiopulmonary exercise test (CPET) and 6-minute walking test (6MWT) uniformly. Anthropometric characteristics, left ventricular ejection fraction (LVEF), and multiple parameters of 6MWT and AT were collected.

RESULTS

The results of the analysis revealed that the 6MWD was correlated with the AT positively [CHF group: r=0.433, heart failure with reduced ejection fraction (HFrEF) group: r=0.395, heart failure with intermediate ejection fraction (HFmEF) group: r=0.477, heart failure with preserved ejection fraction (HFpEF) group: r=0.445; all P<0.05]. The regression analysis showed that the linear equation model developed can predict exercise intensity based on AT (EIAT) by exercise intensity based on 6MWD (EI6MWD), the aerobic exercise intensity based on AT and 6MWD respectively, of CHF patients.

CONCLUSIONS

There is a correlation between EI6MWD and EIAT. 74.6-87.4% of EI6MWD in patients with CHF is equivalent to EIAT. It is feasible to establish the aerobic exercise intensity of patients with CHF equivalent to AT based on 6MWD.