1.4\ Great Artery Short-Axis View

(M-Mode Scan at Pulmonary

Valve Level)

Fig. 6.4  Great artery short-axis view (M-mode scan at pulmonary valve level)

1.4.1\ Scanning Method

The patient lies supine or on the left position. The transducer is placed at left parasternal edge (second to third intercostal space). In the main pulmonary artery long-axis view, the sample line of M-mode passes through the posterior pulmonary valve.

1.4.2\ Section Structure

Pulmonary valve tracing is stressed on in this view, including a wave, b point, cd segment, d point, e point, and f point. The a wave, e point, and f point are shown in this image.

1.4.3\ Measuring Method and Normal Value

The depth of a wave is 2–3 mm.

1.4.4\ The Clinical Application

Changes during the abnormal cardiac cycle in amplitude and waveform of pulmonary valve can be observed in this view.

2.1.1\ Scanning Method

The patient lies flat or on the left side. The transducer is placed in the left parasternal area (second to fifth intercostal space). The beam point is directed towards the right shoulder.

2.1.2\ Section Structure

Left atrium, right ventricle, left ventricle, interventricular septum, mitral valve, right coronary valve, noncoronary valve, anterior aortic root wall connecting with interventricular septum, posterior aortic root wall joining up anterior mitral valve, and posterior left ventricular wall

are the main structures shown in the parasternal long-axis view.

2.1.3\ Measuring Method and Normal Value

Posterior–anterior dimensions of left or right ventricular cavity and of left atrial cavity can be obtained in this view. Ventricular cavities are measured at the level of mitral valve chordae in diastole. Normal dimensions of left ventricle and right ventricle are 38 ± 10 and 25 ± 10 mm. Normal dimension of left atrium is 33 ± 5 mm, which is measured at the middle of left atrium in

systole. Diameter of aortic valve annulus is 20 ± 4 mm measured from the aortic wall anterior inner edge to the posterior inner edge at the attaching point of aortic valve to the wall in systole. Diameter of aortic sinus is 26 ± 8 mm measured from the anterior inner edge to the posterior inner edge at the knuckle of the sinus in systole. Diameter of ascending aorta is 25 ± 10 mm measured at the point 2 cm above the sinus in systole. Diameter (anterior to posterior) of coronary sinus is 7 ± 4 mm measured from anterior inner edge to posterior inner edge.

2.1.4\ The Clinical Application

Dimension and movement of aortic root, thickness and activity of anterior right ventricular wall, opening–closure activity and thickness of mitral valve or of aortic valve, motion and thickness of interventricular septum or of posterior left ventricular wall, continuity of anterior aortic wall with interventricular septum, etc., are the routine items to be observed. Some rheumatic heart disease and congenital heart disease can also be detected in this view. A dilated coronary sinus is seen in the persistent left superior vena cava.

2.2.1\ Scanning Method

The patient lies flat or on the left lateral position. The probe is put near the left sternal edge (second to third intercostal space). The ultrasound beam is perpendicular to the left ventricular long-axis view by tilting the probe towards the right shoulder in a direction from aorta to mitral valve.

2.2.2\ Section Structure

From the near to the distant, chest wall, right ventricular outflow tract, aorta with three aortic valves, left atrium, right atrium, descending aorta, and pulmonary artery with its valves on the right side of the section can be visualized.

2.2.3\ Measuring Method and Normal Value

This is a cross-sectional cut at the base of the heart where the size ratio of aortic root to left atrium to right atrium is about 1:1:1.

2.2.4\ The Clinical Application

Thickness, echogenicity, and activity of the aorta can be seen. Relationship between the aorta with pulmonary artery at their onset sites can be confirmed. Thickness and continuation of supraventricular crest, left atrium, and acoustic transmission of left atrial appendage can also be visualized.