The use of live three-dimensional Doppler echocardiography in the measurement of cardiac output - An in vivo animal study

Clinical Care Center for Congenital Heart Disease, Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA.
Journal of the American College of Cardiology (Impact Factor: 15.34). 03/2005; 45(3):433-8. DOI: 10.1016/j.jacc.2004.10.046
Source: PubMed

ABSTRACT The purpose of this study was to investigate whether cardiac output (CO) could be accurately computed from live three-dimensional (3-D) Doppler echocardiographic data in an acute open-chested animal preparation.
The accurate measurement of CO is important in both patient management and research. Current methods use invasive pulmonary artery catheters or two-dimensional (2-D) echocardiography or esophageal aortic Doppler measures, with the inherent risks and inaccuracies of these techniques.
Seventeen juvenile, open-chested pigs were studied before undergoing a separate cardiopulmonary bypass procedure. Live 3-D Doppler echocardiography images of the left ventricular outflow tract and aortic valve were obtained by epicardial scanning, using a Philips Medical Systems (Andover, Massachusetts) Sonos 7500 Live 3-D Echo system with a 2.5-MHz probe. Simultaneous CO measurements were obtained from an ultrasonic flow probe placed around the aortic root. Subsequent offline processing using custom software computed the CO from the digital 3-D Doppler DICOM data, and this was compared to the gold standard of the aortic flow probe measurements.
One hundred forty-three individual CO measurements were taken from 16 pigs, one being excluded because of severe aortic regurgitation. There was good correlation between the 3-D Doppler and flow probe methods of CO measurement (y = 1.1x - 9.82, R(2) = 0.93).
In this acute animal preparation, live 3-D Doppler echocardiographic data allowed for accurate assessment of CO as compared to the ultrasonic flow probe measurement.

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