As. Anayiotos et al., Morphological evaluation of a regurgitant orifice by 3-D echocardiography:Applications in the quantification of valvular regurgitation, ULTRASOUN M, 25(2), 1999, pp. 209-223
The clinical evaluation of blood flow regurgitation through a heart valve o
r stenotic lesion is an unresolved problem, The proximal flowfield region h
as been the study focus in the last few years; however, investigators have
failed to identify an accurate and reliable calculation scheme due to lack
of geometric information about the shape and size of the regurgitating or s
tenotic orifice. Presented here is a superior method of calculation, by usi
ng three-dimensional (3-D) echocardiography combined with Doppler velocimet
ry. The geometric structure of the orifice in a regurgitating porcine prost
hetic valve in vitro was formulated by 3-D image construction of sequential
ly obtained 2-D images. The velocity flowfield was accessed by color Dopple
r flow mapping (CD) and continuous-wave Doppler (CW), Two accurate methods
of calculation of regurgitant variables were developed. The first method ca
lculated peak regurgitant flow rate from CD and the second method calculate
d regurgitant flow volume from CW, Both methods showed excellent correlatio
n with the corresponding true values from an electromagnetic flowmeter. The
promising preliminary results in such a realistic porcine model indicate t
he possibility of establishing a routine procedure to be tested in the clin
ical setting. (C) 1999 World Federation for Ultrasound in Medicine & Biolog
y.