Doppler Echocardiography
A family of ultrasound techniques that measure the velocity and direction of blood flow through the heart and great vessels. Essential for valvular assessment and diastolic function.
Doppler echocardiography uses the Doppler effect, the frequency shift of ultrasound waves reflected from moving red blood cells, to derive blood-flow velocity and direction. Three main modes: pulsed-wave (PW) for localised low-velocity flow, continuous-wave (CW) for high-velocity flow (e.g. across stenotic valves), and color-flow Doppler for spatial mapping of flow direction.
Doppler is mandatory for grading valvular stenosis and regurgitation, estimating pulmonary pressures from the TR jet, and evaluating diastolic function via mitral inflow E / A velocities.
Tissue Doppler imaging (TDI) extends the technique to measure myocardial tissue velocities directly (e’, the early diastolic mitral-annular tissue velocity, is the key derived parameter for E/e’ and diastolic-function grading).