Evaluation of descending aortic flow volumes and effective orifice area through aortic coarctation by spatiotemporal integration of color Doppler data: An in vitro study

Flow volumes in an in vitro model of the aorta with 3 different degrees of stiffness (stiff, moderately stiff, and compliant) proximal to a coarctation were calculated by using a digital color Doppler echocardiography flow calculation method that semiautomatically integrates spatial and temporal color flow velocity data. These flow volumes were compared with those obtained by the conventional pulsed Doppler method with reference to ultrasonic flowmeter. Flow volumes determined by the automated method agreed well with those obtained by ultrasonic flowmeter, even in this compliant aorta model with vessel size changing with pulsation, whereas the pulsed Doppler method overestimated the reference data, especially for more compliant descending aortic segments. The combination of flow data with continuous wave Doppler allows definition of effective orifice area for coarctation.