Fig. 6.38  Transesophageal aortic root long-axis view

2.34.1\ Scanning Methods

The patient lies on the left side in a lateral position. The transducer is placed at a distance of about 32–35 cm from the incisor teeth with 120° anticlockwise rotation of the beam on the base of aortic root long-axis view.

2.34.2\ Section Structure

Aortic root, including aortic valve annulus, aortic valve, aortic sinus, and a part of ascending aorta, is visualized in this view.

2.34.3\ Measuring Method and Normal Value

Diameters of aortic valve annulus and aortic sinus are 20 ± 4 and 30 ± 34 mm.

2.34.4\ The Clinical Application Value

Lesions of aortic valve, such as aortic valve vegetation, can usually be ascertained in this view.

3.1.1\ Scanning Methods

The patient lies on the left side or in 30–45° lateral position (semirecumbent on his or her left side). In the apical four-chamber view or left-­heart two-cham- ber view, the sample volume is placed in the left ventricle just below the tip of the mitral valve leaflet.

3.1.2\ Section Structure

The Doppler spectrum of transmitral blood flow taken diastole is displayed as a narrow trace above the zero line with two peaks. The first peak is called E wave as an atrial passive filling flow, while the second peak is A wave caused by atrial systole. The waves will be confluent when the heart rate is fast.

3.1.3\ Measuring Method and Normal Value

Peak velocities of E and A can be measured in this view. The normal value of the maximum velocity (Vmax) of E wave is 0.6–1.3 m/s with an average 0.90 m/s. The Vmax of A wave is 0.4– 0.6 m/s. The ratio of E wave to A wave (E/A) is 1.4–2.4 (even to 4 in children).

3.1.4\ The Clinical Application Value

mate left ventricular diastolic function. E/A ≤ 0.75, a slow relaxation pattern, suggests mild diastolic dysfunction. 0.75 < E/A < 1.5, which may be a false normal pattern, suggests moderate left ventricular diastolic function. E/A > 1.5 or more, a restrictive pattern, usually represents severe left ventricular diastolic dysfunction. When mitral stenosis occurs, velocity of the diastolic mitral flow will increase and the pressure halftime of E wave will be prolonged. Pressure halftime of E wave can also be used to estimate the mitral valve area, but it is limited in the presence of severe mitral or aortic regurgitation. Mitral stenosis or mitral regurgitation can be diagnosed in this view. When mitral insufficiency is present, a spectrum of high velocity below the reference line in systole can be recorded just above the mitral valve.

3.1.5\ Notice

The sample volume should be put at the site 1–2 cm away from mitral valve orifice. E wave deceleration time (Dcet) which is 160–240 ms in the normal can be used to assess left ventricular diastolic function, too.

3.2.1\ Scanning Methods

The patient lies on the left side or in left 30–45° lateral position.

3.2.2\ Characteristics oftheFlow Signals

adjacent zone of the blood flow. During middle diastole mitral valve is semiclosed and the color of blood flow becomes dark as the flow through the orifice decreases.

3.2.3\ The Clinical Application Value

During early diastole mitral valve is open and the blood flows from left atrium to left ventricle like a red band with a brightest area in center to fill in the left ventricular inflow tract. A blood flow in darker blue can be seen at two sides of the mitral orifice due to occurrence of the eddy flow at the

Mitral stenosis or mitral regurgitation can be visualized in this view. Mitral insufficiency is the retrograde blood flow in a blue or mosaic pattern from left ventricle to left atrium in systole.

3.3.1\ Scanning Method

The patient lies on the left side or in left 30–45° lateral position. In the apical four-chamber view or parasternal four-chamber view or right ventricular inflow tract view, the sample volume is placed in the left ventricle just at the tip of tricuspid valve leaflet.

3.3.2\ Section Structure

Changes of tricuspid valve blood spectrum are usually influenced by patient’s breath. The spectral Doppler of a normal tricuspid flow shows as a narrow spectrum above the zero line with two peaks like “M” profile, in which the first peak is E wave, representing an early passive filling flow of right atrium, and the second peak is A wave caused by the atrial systole. E and A waves can become a fused wave when heart rate increases.

3.3.3\ Measuring Method and Normal Value

Velocities of E and A waves can be taken in this view. The normal and abnormal patterns are similar to those of the mitral valve but with lower velocity values. The maximum velocity of normal tricuspid valve flow is 0.3–0.7 cm/s. E/A is about 1.6 in the end of expiration, but A wave is usually greater than E wave in normal fetus or normal neonate.

3.3.4\ The Clinical Application Value

Mild regurgitation of tricuspid valve can be seen in some healthy persons. When right ventricle and tricuspid valve annulus are dilated, pathologic regurgitation of tricuspid valve may occur, in which a systolic turbulent flow can be found as a single peak and broaden spectrum below the reference line by putting the sample volume at the atrial side of tricuspid valve.