[Measurement of arterial distensibility by the QKd method a new vascular marker]

Distensibility is the ability of large elastic arteries to increase in diameter from diastole to systole. Pulse wave velocity (PWV) is one of the ways to measure this parameter. Several techniques, including QKd, are able to measure PWV.

QKd is the time interval between the Q wave on EKG and auscultation of the second Korotkoff's sound at the brachial artery. QKd is measured by a specific apparatus that registers ambulatory blood pressure as well as EKG (normal > 200 ms). Arterial distensibility seems to be able to predict cardiovascular morbidity and QKd has been demonstrated to predict such morbidity in a sample of elderly hypertensives. Currently the relationship between QKd and prognosis is under investigation in systemic sclerosis (ERAMS study).

QKd is a noninvasive ambulatory method that measures arterial distensibility as well as blood pressure.