Low ankle brachial index is associated with the magnitude of impaired walking endurance in patients with heart failure.

BACKGROUND: Measurement of the ankle brachial index (ABI) is a simple, noninvasive means of diagnosing peripheral arterial disease, and has been shown to be associated with mortality rate. Here, we examined the association between ABI and physical function in patients with heart failure (HF).

METHODS: The study population consisted of 524 admitted patients (67.2±13.9years, 343 males) with HF. Blood pressure and the ABI were determined by oscillometry. Prior to hospital discharge, ABI, 6-minute walking distance, walking velocity, handgrip strength, quadriceps isometric strength, and standing balance were determined. The 524 patients were divided according to ABI as follows: ABI≤0.90 (low ABI), ABI 0.91 to 0.99 (borderline ABI), and ABI 1.00 to 1.40 (normal ABI).

RESULTS: Lower ABI values were associated with shorter 6-minute walking distance (p trend=0.001), slower walking velocity (p trend=0.023), and poorer standing balance (p trend=0.048). There were no significant associations between ABI and handgrip strength or quadriceps isometric strength. After adjusting for potential confounders, patients with ABI≤0.90 had shorter 6-minute walking distance compared to those with ABI 1.00 to 1.40 (adjusted mean value: 344m vs. 395m, respectively, p<0.001). There were no significant differences in any of the other physical function parameters examined.

CONCLUSIONS: In patients with HF, low ABI is associated with the magnitude of impairment in walking endurance.