Echocardiography

Regurgitant Lesions Valvular regurgitation can be diagnosed with PW Doppler, by interrogating the area immediately behind the valve of interest and recording retrograde flow. Localization of regurgitant jets is often assisted by color flow mapping, which can guide the operator towards an eccentric or otherwise elusive jet, ie, “color-guided” Doppler sampling. In order to resolve […]

Applications Thus, the application of equations 2, 3 and 5 above allow the determination of transvalvular pressure gradients and valve areas, providing valuable information in a variety of clinical settings. One example of the value of using the aortic valve area in conjunction with the gradient estimation is in aortic stenosis of intermediate severity, especially […]

Pressure Gradients Knowing the difference between the velocities of blood flow in any two regions of the heart, the pressure gradient between those two regions (eg, across a stenosis) can be calculated by applying the modified Bernouilli equation: This modification of the original Bernouilli equation omits effects due to viscous friction and flow acceleration, both […]

The recent introduction of Doppler-echocardio-graphic techniques into cardiac ultrasound examination has meant that cardiac function (in addition to the structural information previously available from two-dimensional echocardiography) can now be evaluated more thoroughly. Doppler-echocardiographic techniques currently enable the noninvasive measurement of pressure gradients across both native and prosthetic valves, across stenoses of great vessels, as well […]