Association between critical limb ischemia and arterial stiffness measured by brachial artery oscillometry

BACKGROUND: Elevated arterial stiffness is associated with increased cardiovascular mortality. The relationship between arterial stiffness and critical limb ischemia (CLI) is not well established. OBJECTIVES: The objective of this study is to analyze the relationship between arterial stiffness indices and the degree of limb ischemia measured by the ankle-brachial index (ABI). METHODS: A cross-sectional study comparing patients with CLI and controls. Arterial stiffness was measured using brachial artery oscillometry. The arterial stiffness indices pulse wave velocity (PWV) and augmentation index normalized to 75 beats/min (AIx@75) were determined. Multiple linear regression was applied to identify predictors of arterial stiffness indices. RESULTS: Patients in the CLI group had higher PWV (12.1±1.9 m/s vs. 10.1±1.9 m/s, p < 0.01) and AIx@75 (31.8±7.8% vs. 17.5±10.8%, p < 0.01) than controls. Central systolic pressure was higher in the CLI group (129.2±18.4 mmHg vs. 115.2±13.1 mmHg, p < 0.01). There was an inverse relationship between AIx@75 and ABI (Pearson coefficient = 0.24, p = 0.048), but there was no relationship between ABI and PWV (Pearson coefficient = 0.19, p = 0.12). In multiple regression analysis, reduced ABI was a predictor of elevated levels of AIx@75 (β = -25.02, p < 0.01). CONCLUSIONS: Patients with CLI have high arterial stiffness measured by brachial artery oscillometry. The degree of limb ischemia, as measured by the ABI, is a predictor of increased AIx@75. The increased AIx@75 observed in CLI may have implications for the prognosis of this group of patients with advanced atherosclerosis.