24-12: Apical Four-Chamber View (AP4)

Technique

• The transducer indicator is directed toward the left axilla or directly posterior to the patient.

• The transducer is placed over the cardiac apex or the point of maximal intensity with the beam directed toward the right clavicle/shoulder in a plane coronal to the heart (Fig. 24.41).

• Identify the left ventricle, right ventricle, left atrium, right atrium, tricuspid valve, mitral valve, and surrounding pericardium (Fig. 24.42).

Abnormal Findings

• Pericardial effusion: Anechoic (black) region noted between the hyperechoic pericardium and the walls of the heart (see Figs. 24.37 and 24.43).

• Dilated right atria/ventricle: If the right ventricle is equal to or larger than the left ventricle in size, or there is poor contractility of the right heart in comparison with the left, it may suggest elevated right-sided pressures as seen with pulmonary emboli and severe pulmonary hypertension (Fig. 24.44).

• Dilated cardiomyopathy: As cardiac remodeling occurs in states of dilated cardiomyopathy, the left ventricle begins to take on more of a dilated balloon-like shape rather than its normal more streamlined bullet-like shape (Fig 24.45).