Points
Pulsed-wave Doppler tissue imaging (PW DTI) is performed in the apical views to acquire mitral annular velocities.
The sample volume should be positioned at or 1 cm within the septal and lateral insertion sites of the mitral leaflets.
It is recommended that spectral recordings be obtained at a sweep speed of 50 to 100 mm/s at end-expiration and that measurements should reflect the average of ≥3 consecutive cardiac cycles.
Primary measurements include the systolic (s) and early (e') and late (a') diastolic velocities.
For the assessment of global LV diastolic function, it is recommended to acquire and measure tissue Doppler signals at least at the septal and lateral sides of the mitral annulus and their average.
In patients with cardiac disease, e' can be used to correct for the effect of LV relaxation on mitral E velocity, and the E/e' ratio can be applied for the prediction of LV filling pressures.
It is preferable to use the average e' velocity obtained from the septal and lateral sides of the mitral annulus for the prediction of LV filling pressures. Because septal e' is usually lower than lateral e' velocity, the E/e' ratio using septal signals is usually higher than the ratio derived by lateral e', and different cutoff values should be applied on the basis of LV EF, as well as e' location.
Using the septal E/e' ratio, a ratio <8 is usually associated with normal LV filling pressures, whereas a ratio >15 is associated with increased filling pressures. When the value is between 8 and 15, other echocardiographic indices should be used.