Congenital heart disease in echocardiography (an approach)

The diagnosis of congenital heart disease in echocardiography is outside the scope of basic echocardiography, however, several common features may be recognized at the point of care which allow for initial stablization and management before a complete echocardiography exam may be performed.

In patients with a high probability of requiring surgical management, a complete transthoracic echocardiography exam may often serve as the most appropriate modality for preoperative definition of anatomy ².

The following steps enumerate one approach to preliminary recognition of basic cardiac anatomical features using common point of care echocardiography views in an adult with clinical features suggestive of previously unrecognized congenital heart disease ³.

Step 1: position of the apex

The initial step should be performed in the subcostal window, seeking visualization a four chamber view; levocardia is established if the apex of the heart is directed to the left, and dextrocardia if directed to the right.

Step 2: establish situs

Inference of atrial situs may be inferred using abdominal situs; the two coincide in >80% of cases, with the latter being easier to recognize. Identification of abdominal situs is possible from the subcostal window; with slight rotation and caudad angulation of the probe, the aorta and inferior vena cava should be visualized as they course into the abdomen. Situs solitus is established with visualization of the aorta to the left of the inferior vena cava, with reversal of position indicating situs inversus. 

Step 3: distinguish the ventricles

The ventricles may be distinguished from one another as follows;

• identification of the atrioventricular (tricuspid and mitral) valves
  • considered the most reproducible and accurate method ¹
    • the right ventricle demonstrates apical displacement of its associated atrioventricular (tricuspid) valve
      • the tricuspid valve is trileaflet, with one leaflet having a chordal attachement to the septum
    • the left ventricle is assocated with a bileaflet mitral valve
      • anterior and posterior leaflets, with no septal insertions
• morphology
  • less reliable than identification of atrioventricular valves, but may serve as supportive evidence
  • the most reliably distinguishing feature of the right ventricle is the moderator band
    • also typically demonstrates an irregular endocardial outline, triangular shape, and the presence of an infundibulum
  • the left ventricle demonstrates a truncated ellipsoidal shape with two separate groups of papillary muscles and a smooth endocardial surface

Step 4: identify the great vessels

Cephalad angulation of the probe from a subcostal or apical window will allow differentiation of the two discrete branches of the pulmonary trunk, in contrast to the more diminutive coronary arteries branching from the aortic root.

See also

• congenital heart disease
• congenital heart disease chest x-ray (an approach)
• cyanotic congenital heart disease
• acyanotic congenital heart disease
• plethoric congenital heart disease
• oligaemic congenital heart disease