Evaluation of patients with only marginally abnormal arm-ankle blood pressure gradients suspected of arterial obliterative disease.

Two groups of patients with only marginally abnormal systolic blood pressure gradients from arm to ankle were studied. Group A consisted of 24 patients, who had arteriography performed for unilateral symptoms. In the non-symptomatic limbs a significant correlation was found between the severity of obliterations and the arm to ankle blood pressure gradients, which in all cases was less than 35 mmHg. In Group B consisting of 55 patients suspected of arterial obliterative disease the arm to ankle pressure gradient was measured at rest and after 2 min. of leg exercise. The diagnostic correctness of the two procedures were analysed by the direct method for evaluation of diagnostic tests using the clinical diagnosis as final diagnostic criterion. The maximal diagnostic correctness was 85 % for the gradient at rest using values between 20 and 25 mmHg as criterion for arterial obliterative disease. It equaled the maximal diagnostic correctness of 87 % of the gradient after exercise using values between 45 and 55 mmHg as criterion.