An index for the measurement of the degree of aortic incompetence

ABSTRACT

It has been noted that under certain conditions a standard sphygmomanometer cuff may act as a valve on the peripheral blood vessles. A pneumatic cuff was employed as a valve on the brachial artery in aortic incompetence, and by obstructing the regurgitant blood a means for measuring its volume was devised. The principle on which this method is based is that of using a special type of sphygmomanometer cuff which at certain pressures exerts a valve-like action on the brachial artery. In aortic incompetence the cuff prevents some of the backward flow, thus increasing the foreward flow. This increase in foreward flow, measured plethysmographically, is used as a basis for calculating indices of regurgitation. The essential feature of this technique is the measurement of forearm-hand blood flows by venous occlusion plethysmography with the limb in the upward and vertical position, and at high ambient temperatures of 30 to 32 oC. A high degree of regurgitation may be indicated by this technic (Summary)