Increased arterial wall stiffness limits flow volume in the lower extremities in type 2 diabetic patients

OBJECTIVE - To document an association between arterial wall stiffness and reduced flow volume in the lower-extremity arteries of diabetic patients. RESEARCH DESIGN AND METHODS - We recruited 60 consecutive type 2 diabetic p atients who had no history or symptoms of peripheral arterial disease (PAD) in the lower extremities and normal ankle/brachial Systolic blood pressure index at the time of the study (non-PAD group) and 20 age-matched nondiabe tic subjects (control group). We used an automatic device to measure pulse wave velocity (PWV) in the lower extremities as an index of arterial wall s tiffness. At the popliteal artery, we evaluated flow volume and the resisti ve index as an index of arterial resistance to blood now using gated two-di mensional cine-mode phase-contrast magnetic resonance imaging. RESULTS - Consistent with previous reports,we confirmed that the non-PAD gr oup had an abnormally higher PWV compared with that of the control group (P < 0.001). To further demonstrate decreased flow volume and abnormal flow p attern at the popliteal artery in patients with a higher degree of arterial wall stiffness, we assigned the 60 non-PAD patients to tertiles based on t heir levels of PWV. In the highest group, magnetic resonance angiograms of the calf and foot arteries showed decreased intravascular signal intensity, indicating the decreased arterial inflow in those arteries. The highest gr oup was also characterized by the lowest late diastolic and total flow volu mes as well as the highest resistive index among the groups. From stepwise multiple regression analysis, PWV and autonomic function were identified as independent determinants for late diastolic flow volume (r(2) = 0.300 P < 0.001). CONCLUSIONS - Arterial wall stiffness was associated with reduced arterial flow volume in the lower extremities of diabetic patients.