Reading transmitral Doppler
The transmitral inflow pattern is one of the most fundamental windows into left ventricular diastolic function, filling pressures, and relaxation physiology.
After aortic valve closure, the LV begins to relax, but both valves remain closed during the isovolumic relaxation time (IVRT). During this phase, LV pressure falls rapidly without any change in ventricular volume.
Once LV pressure drops below left atrial (LA) pressure, the mitral valve opens and ventricular filling begins.
The first peak is the E wave (early diastolic filling).
This represents passive LV filling, driven by the pressure gradient between the LA and the relaxing LV. In healthy young adults, E velocity is typically dominant because ventricular relaxation is efficient and suction is preserved.
After the E-wave peak, flow slows as the LA-LV pressure gradient declines. This creates the deceleration slope, and the time from peak E to baseline is the deceleration time (DT), an important marker of LV compliance and filling pressure.
A brief phase of minimal flow may follow: diastasis, where LA and LV pressures nearly equalize.
The second peak is the A wave, generated by atrial contraction (atrial kick), which contributes to late ventricular filling.
Key quantitative parameters from transmitral Doppler:
🛑E velocity: peak early filling velocity
🛑A velocity: peak atrial filling velocity
🛑E/A ratio: quick assessment of diastolic filling pattern
🛑IVRT: time from aortic valve closure to mitral valve opening; reflects LV relaxation
🛑DT (deceleration time): reflects LV compliance and filling pressure
🛑VTI (velocity-time integral): total blood flow contribution during filling
🛑DFP (diastolic filling period): duration of ventricular filling
Clinical interpretation:
- A reduced E wave with dominant A wave (E/A <1) often suggests impaired relaxation.
- A very tall E wave with short DT may indicate elevated LV filling pressures and restrictive physiology.
- A seemingly normal E/A ratio can be deceptive (pseudonormal pattern), this is why tissue Doppler and LA assessment matter.
Transmitral Doppler is not just a waveform, it is a hemodynamic conversation between the left atrium and left ventricle.
Ref: Otto Catherine clinical textbook