Ankle Blood Pressure: A Novel Measure Affecting Central Arterial Wave Reflection?

Objective There is an increasing recognition that central aortic pressure is more relevant than peripheral (brachial) measure for the prediction and pathophysiology of cardiovascular disease. Central pressure is greatly influenced by the phenomenon of arterial wave reflections returning from the peripheral vasculature, which can be quantified by augmentation index. Primary wave reflections returning to the heart are thought to come from the lower body (e.g., lower limbs). Accordingly, the primary aim of the present study was to determine the association between central augmentation index and arterial blood pressures recorded in both the upper and lower limbs. Methods A total of 1,189 apparently healthy adults (567 males and 622 females) of varying ages were studied. Brachial and ankle blood pressure, carotid augmentation index, and brachial‐ankle pulse wave velocity were measured. Results All of the blood pressure (brachial and ankle, systolic, mean, and diastolic) measurements were significantly associated with carotid augmentation index. Among them, ankle mean arterial pressure was the strongest correlate of carotid augmentation index (r=0.56, P<0.05). This relation remained highly significant even after the influence of brachial blood pressure or age was accounted for in the partial correlation analyses. Moreover, stepwise regression analyses revealed that ankle mean arterial pressure was the strongest independent predictor of carotid augmentation index among all of the blood pressure measurements. Conclusion Ankle blood pressure is strongly associated with the augmentation of central blood pressure, and this relation is independent of other blood pressure measures (brachial blood pressure).