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6  Echocardiography

113

 

 

3.4\ Tricuspid Valve Orifice Color

Doppler Flow Mapping

a

b

Fig. 6.42  Color Doppler flow mapping of the tricuspid valve orifice. (a) Diastole. (b) Systole

3.4.1\ Scanning Method

The patient lies on the left side or in left 30–45° lateral position. The apical four-chamber view or parasternal four-chamber view or right ventricular inflow tract view is used.

3.4.2\ Section Structure

During early diastole tricuspid valve is open and the blood flows through the orifice like a red band with a brightest area in center to fill in the right ventricular inflow tract. A blood flow in darker blue can be seen at two sides of the orifice due to occurrence of the eddy flow at the adjacent zone of the blood flow. During mid-diastole tricuspid valve is in semiclosed and the color of blood flow becomes dark as the flow through the orifice decreases.

3.4.3\ The Clinical Application Value

The apical four-chamber view is the optimal view to display flow across the tricuspid valve. When right ventricle and tricuspid valve annulus are dilated, pathologic regurgitation of tricuspid valve may occur, which is shown as a mosaic

color jet with more blue from the orifice into right atrium in systole. Area of the regurgitant jet can be obtained in this view. According to the ratio of the regurgitant jet area to the right atrial area, severity of tricuspid regurgitation can be evaluated: <0.2 being mild, 0.2–0.4 being moderate, and >0.4 being severe. Right atrial pressure can also be estimated in this view. When the right atrial size is normal and there is complicated mild tricuspid valve regurgitation, the right atrial pressure is about 5 mmHg. Right atrial pressure is about 10 mmHg when the right atrium is dilated slightly with moderate tricuspid regurgitation, while right atrial pressure is about 15 mmHg in the patient with obvious right atrial dilatation and severe tricuspid valve regurgitation.

3.4.4\ Notice

Mild insufficiency of tricuspid valve can exist in some normal cases, in which a regurgitant flow in blue can be shown from the tricuspid valve orifice to right atrium in systole.

114

S. He

 

 

3.5\ Spectral Doppler of the Aortic

Valve Orifice

a1

a2

 

 

 

 

 

RV

 

LV

 

 

 

 

AV

 

MV

 

 

 

 

Ao

 

LA

b

c

Fig. 6.43  Spectral Doppler of the aortic valve orifice. (a1, a2) Systole. (b) Flow spectrum in left ventricular outflow tract. (c) Flow spectrum above aortic valve

3.5.1\ Scanning Method

The patient lies on the left side or in left 30–45° lateral position. The apical five-chamber view or apical left ventricular long-axis view is used. Sample volume is placed above the valves.

3.5.2\ Section Structure

The systolic Doppler profiles in normal left ventricular outflow tract and above normal aortic valve orifice are the narrow spectrums below the zero line.

3.5.3\ Measuring Method and Normal

Value

3.5.4\ The Clinical Application Value

When the obstructions occur at aortic valve orifice, the spectrums will be widened and the frequency shift increased which represent an increase in blood flow velocity caused by the stenosis.

3.5.5\ Notice

There can be a mild aortic regurgitation in normal person, which can be detected as a diastolic spectrum above the spectral reference line at ventricular outflow tract.

In this view, normal velocity values at ventricular outflow tract and above aortic valve orifice are 0.44–1.28 and 0.90–1.70 m/s (mean: 1.35 m/s).

6  Echocardiography

115

 

 

3.6\ Color Flow Mapping

of the Aortic Valve Orifice

a

b

Fig. 6.44  Color flow mapping of the aortic valve orifice. (a) Systole. (b) Diastole

3.6.1\ Scanning Method

The patient lies on the left side or in left 30–45° lateral position. The apical five-chamber view or apical left ventricular long-axis view is used.

3.6.2\ Section Structures

During early-mid-systole, the blood flow at left ventricular outflow tract and aortic valve orifice is shown as a wide blue trace with a bright mosaic color area at the center of the flow.

3.6.3\ The Clinical Application Value

When aortic stenosis exists, a systolic mosaic color jet can be demonstrated at the aortic orifice. The jet usually becomes widened like a spring after crossing the aortic valve. The more slender the jet is, the more severe the aortic stenosis is. When aortic valve insufficiency occurs, a regur-

gitant jet can be visualized flowing in a retrograde direction, as a mosaic color code with red background, through the incompetent valve into the left ventricle. The width of the left ventricular outflow tract or of the regurgitant jet is measured at a location immediately below the aortic valve annulus. The ratio of regurgitant jet width to left ventricular outflow tract can be used to evaluate the regurgitant severity: 1–24% is trivial, 25% is mild, 25–46% moderate, and >64% severe.

3.6.4\ Notice

A trivial to mild regurgitation can be seen in some normal persons, in which a slender regurgitant jet can be detected flowing from the subvalve into the left ventricular outflow tract in this view.

116

3.7\ Spectral Doppler of Pulmonary

Valve Orifice

a1

a2

b1

b2

RVOT

TV

RA

Ao

RPA

c

d

S. He

PV mPA

LPA

DAo

Fig. 6.45  Spectral Doppler of pulmonary valve orifice. (a) Aortic valve short-axis view. (b) Main pulmonary long-­axis view. (c) Doppler spectrum in right ventricular outflow. (d) Doppler spectrum at pulmonary valve tract orifice