24-10: Parasternal Long-Axis View (PSLA)

Technique

• The transducer indicator is directed at the right clavicle or shoulder.

• The transducer is placed in the 4th or 5th left parasternal intercostal space and the beam is directed posteriorly (Fig. 24.35).

• Identify the right ventricle, left atrium, left ventricle, mitral valve, aortic valve, aortic root, aortic outflow tract, and surrounding pericardium (Fig. 24.36).

Abnormal Findings

• Pericardial effusion: Anechoic (black) region noted between the hyperechoic (bright) pericardium and the walls of the heart (see Fig. 24.37). In this view, pericardial effusion may be distinguished from a left-sided pleural effusion by its relationship to the descending thoracic aorta.

• Aortic root dilatation: An aortic root measurement greater than 3.8 to 4.0 cm is abnormal and indicates aneurysmal dilatation that may suggest aortic dissection in the appropriate clinical setting. Further evaluation is recommended.

• Dilated descending aorta: The transverse descending thoracic aorta can be seen in the far field in this view posterior to the left atrium. A descending thoracic aorta greater than 4.0 cm is abnormal and indicates aneurysmal dilatation that may suggest aortic dissection in the appropriate clinical setting. Further evaluation is recommended.

• Poor left ventricular function: Gross estimates of left ventricular function may be made by observing the anteroposterior motion of the mitral valve, the increase in myocardial thickness with contraction, and the extent to which the anterior and posterior walls of the left ventricle approach each other in systole.