Tissue Doppler echocardiography

Tissue Doppler echocardiography (TDE) is a medical ultrasound technology, specifically a form of echocardiography that measures the velocity of the heart muscle (myocardium) through the phases of one or more heartbeats by the Doppler effect (frequency shift) of the reflected ultrasound.

However, as this is a spectral technique, it is important to realise that measurement of peak values is dependent on the width of the spectrum, which again is a function of gain setting.

[citation needed] Pulsed wave spectral tissue Doppler has become a universal tool that is part of the general echocardiographic examination.

The velocity curves are in general taken from the base of the mitral annulus at the insertion of the mitral leaflets, in the septal and lateral points of the four chamber view, and eventually the anterior and inferior points of the two-chamber views.

Annular velocities summarize the longitudinal contraction of the ventricle during systole, and elongation during diastole.

S' has become a reliable measure of global function[5][6][7][8] It shares the advantage of annular displacement, that it is reduced also in hypertrophic hearts with small ventricles and normal ejection fraction (HFNEF), which is often seen in Hypertensive heart disease, Hypertrophic cardiomyopathy and Aortic stenosis.

After the early relaxation, the ventricular myocardium is passive, the late velocity peak a' is a function of atrial contraction.

[19][20] One of the main advantages of tissue Doppler is that diastolic and systolic function can be measured by the same tool.

The sudden systolic overload of which Pickelhaube spike is an expression can act as a trigger for the onset of ventricular arrhythmias.

[25] Normal gender and age related reference values For both S', e' and a' have been established in the large HUNT study, comprising 1266 subjects free of heart disease, hypertension and diabetes.

There is also a significant correlation between S' and e', also in healthy subjects, showing the connection between systolic and diastolic function.

[citation needed] Unlike spectral Doppler, colour tissue Doppler samples velocities from all points of the sector, by shooting two pulses successively, and calculating the velocity from the phase shift between them by autocorrelation.

Tissue Doppler has no particular advantage in the current form but may be used to study low flow thrombogenic states like spontaneous echo contrasts.

Spectral tissue velocity curves from the mitral annulus at the septal (left) and lateral (right) points. The curves show multiple heartbeats.
Single spectral tissue velocity curve from the mitral annulus. The curve shows velocities towards the probe (positive velocity) in systole, and away from the probe (negative velocities) in diastole. The most useful measures are the peak velocities, in systole S' and in early diastole (e') and late diastole during atrial contraction (a').
relation between mitral flow and mitral annulus velocity. Left: Normal person with good diastolic function; high E and e', normal E/e'. Middle, patient with diastolic dysfunction without increased filling pressure; low E and e', normal E/e' ratio. Left, patient with diastolic dysfunction and increased filling pressure; high E, low e' and high E/e'. The S' is reduced in proportion to the e'
Age dependent normal values for S', e' and a'.
Colour tissue Doppler traces from a normal subject Left: traces from the septum and mitral ring. The similarities of the curve shape to spectral Doppler is evident. Right: multiple traces from sites along the septum. The decreasing velocities from base to apex is evident.