Semi-automated analysis of color M-mode echocardiographic images for determining transmitral pressure gradients using
M S Firstenberg1, N L Greenberg, M J Garcia
1The Cardiovascular Imaging Center, The Cleveland Clinic Foundation, Cleveland, Ohio, USA.
Unlabelled:
We hypothesize that a simplified version of the Euler equation (SEE) utilizing differences in velocity over a distance and time as obtained by Color Doppler M-mode (CMM) echocardiography can approximate actual peak transmitral pressure gradients deltaP(TM).
Methods:
In 14 patients undergoing open-heart surgery, deltaP(TM) was measured under various hemodynamic conditions using 2 high fidelity transducers, 5 cm apart. Transesophageal CMM images were simultaneously acquired and a customized image analysis application was used to abstract spatiotemporal velocity characteristics. Using both the SEE and a simplified Bernoulli equations, deltaP(TM) were determined and compared to the actual deltaP(TM).
Results:
While the simplified Bernoulli equation resulted in a poor estimate (y=0.075x+0.71, r=0.45), the deltaP(TM) obtained using the SEE correlated strongly (y=0.79x+0.48, r=0.91) with the actual measurements.
Conclusions:
Semi-automated analysis of CMM images using a SEE can accurately estimate actual deltaP(TM).
