Skip to Main Content

Key Features

Essentials of Diagnosis

  • Marked cyanosis present from birth

  • ECG with left axis deviation, right atrial enlargement, and left ventricular hypertrophy (LVH)

General Considerations

  • There is complete atresia of the tricuspid valve with no direct communication between the righ tatrium and the right ventricle (RV)

  • There are two types atresia based on the relationship of the great arteries: normally related or transposed great arteries

  • Because there is no flow to the RV, development of the RV depends on the presence of a ventricular left-to-right shunt

  • Severe hypoplasia of the RV occurs when there is no ventricular septal defect (VSD) or when the VSD is small

Clinical Findings

  • Cyanosis

  • Growth and development are poor

  • Exhaustion during feedings

  • Tachypnea

  • Dyspnea

  • Heart failure (HF) may develop in patients with increased pulmonary blood flow

  • A murmur from the VSD is heard best at the lower left sternal border

  • Digital clubbing is present in older children with long-standing cyanosis



  • Radiography

    • Heart is slightly to markedly enlarged

    • Main pulmonary artery segment is usually small or absent

    • Size of the right atrium is moderately to massively enlarged, depending on the size of the communication at the atrial level

    • Pulmonary vascular markings

      • Usually decreased

      • May be increased if pulmonary blood flow is not restricted by the VSD or pulmonary stenosis

  • Echocardiography

    • Two-dimensional echocardiography is diagnostic

    • Color-flow Doppler imaging can help identify atrial level shunting and levels of restriction of pulmonary blood flow

Diagnostic Procedures

  • Electrocardiography

    • Shows marked left axis deviation

    • P waves are tall and peaked, indicative of right atrial hypertrophy

    • LVH or LV dominance is found in almost all cases

    • RV forces are usually low or absent

  • Cardiac catheterization and angiocardiography

    • Reveals a right-to-left shunt at the atrial level

    • Right atrial pressure is increased if the atrial septal defect (ASD) is restrictive

    • LV and systemic pressures are normal

    • Catheter cannot be passed through the tricuspid valve from the right atrium to the RV

    • A balloon atrial septostomy is performed if a restrictive patent foramen ovale (PFO) or ASD is present


  • In infants with unrestricted pulmonary blood flow, conventional anticongestive therapy with diuretics and afterload reduction should be given until the infant begins to outgrow the VSD

  • In infants with diminished pulmonary blood flow, PGE1 is given until an aortopulmonary shunt (BT shunt or ductal stent) can be performed.

  • Sometimes, a pulmonary artery band is needed to protect the pulmonary bed from excessive flow and development of pulmonary vascular disease

  • A Glenn procedure (superior vena cava to pulmonary artery anastomosis) is done with takedown of the aortopulmonary/BT shunt at 4–6 months when saturations begin to fall

  • Completion of the Fontan procedure (redirection of inferior vena ...

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.