A proposal of a physical exploration method to assess clinically the endothelial function in humans

Background: Assessment of endothelial function in humans is carried out by means of expensive and invasive methods. These procedures measure the endothelial response to pharmacological or mechanical stimulation. Objective: To establish a clinical method to estimate the endothelial function available in any clinical revision. Patients and methods: Fifty one healthy volunteers, 30 women and 21 men, with a mean age of 20.9 ± 1.4 years, weight of 64.5 ± 12.8 kg and height of 1.66 ± 0.09 m were included in a clinical, comparative and open trial. The wrist diastolic blood pressure (WDBP) was measured with an Omron Hem-601 semiautomatic monitor device before and 2, 5 and 7 minutes after occlusion of brachial artery. As reference test, the brachial artery lumen was measured by means of a Doppler Ultrasound Toshiba Sonolayer device before and after 1 minute of the arterial occlusion. Results: The wrist diastolic blood pressure was of 68.9 mmHg before the stimulus and 61.2, 62.9 and of 63.1 mmHg at 2, 5 and 7 minutes after arterial occlusion (p < 0.00001). Arterial diameter increased 0.66 ± 0.37 mm and so did the brachial lumen area with 3.6 ± 2.2 mm2 after the stimulus. The wrist diastolic blood pressure differences at 2, 5 and 7 minutes were of -7.6, -5.9 and -5.7 mmHg (p < 0.001) and the addition of these differences was of -19.4 mmHg (p < 0.000001). This method had sensitivity of 89% and a positive predictive value of 91%. Conclusion: This method is an easy physical exploration maneuver and may be a useful clinical indicator of endothelial dysfunction that identifies cardiovascular high risk subjects.