Total anomalous pulmonary venous return

Background

Tapvr.jpg
  • A cyanotic congenital heart defect
  • All four pulmonary veins drain into the systemic venous circulation rather than into the left atrium.
  • Four anatomic forms:
    • Supracardiac (46%): pulmonary veins connect to the cardinal venous system (left innominate vein, superior vena cava, azygous vein)
    • Cardiac (20%): pulmonary veins connect to the posterior aspect of the coronary sinus or directly to the right atrium
    • Infracardiac (23%): Pulmonary veins drain into the portal vein, hepatic vein, or IVC
    • Mixed (11%): Combination of connections that enter at 2 or more levels.
  • Firth most common cause of cyanotic congenital heart disease [1]

Physiology

  • All oxygenated pulmonary venous blood mixes with deoxygenated blood from the systemic venous system
  • Mixed/partially oxygenated blood then shunted right to left (through patent foramen ovale, PDA or an ASD), resulting in cyanosis
  • The right atrium and ventricle become dilated because it receives blood from both pulmonary and systemic venous systems.
  • In obstructed forms of TAPVR, the pulmonary venous system is compressed by surrounding structures
    • May lead to RV hypertrophy and pulmonary vascular changes that may result in RV failure

Clinical Features

  • Varies with the degree of obstruction and the degree of left-to-right shunting.
  • Respiratory distress and tachypnea
  • Hypotension
  • Poor feeding, failure to thrive. 
  • Fixed S2 split due to RV overload
  • Systolic ejection murmur due to increased stroke volume across the pulmonary valve
  • Hepatomegaly due to right-sided failure
  • Variable degrees of cyanosis

Differential Diagnosis

Congenital Heart Disease Types

Evaluation

Snowman sign
  • Echocardiography
  • Angiography: gold standard but generally no longer required given other less invasive diagnostic modalities
  • CT or MRA
  • Chest x-ray
    • Nonspecific findings, cannot be used to make diagnosis
    • Prominence of pulmonary arteries
    • Enlarged cardiac silhouette
    • Classic snowman sign (for supracardiac TAPVC)
  • ECG
    • May be normal
    • May have evidence of right ventricular hypertrophy or right atrial enlargement

Management

  • Stabilize cardiopulmonary function prior to surgery
  • Supplemental oxygen
  • Mechanical ventilation
  • Inotropic agents (eg, dopamine and dobutamine) improve myocardial contractility
  • Diuretic therapy, (eg, furosemide) reduce preload, relieve volume overload and pulmonary congestion
  • Prostaglandin E1 may be required to prevent closure of ductus arteriosus to maintain systemic cardiac output
  • Primary surgical repair

Disposition

  • Admit

See Also

External Links

References

  1. Reller MD. Prevalence of congenital heart defects in metropolitan Atlanta, 1998-2005. J Pediatr. 2008;153(6):807-13.
  2. Knipe K et al. Cyanotic congenital heart diseases. Radiopaedia. http://radiopaedia.org/articles/cyanotic-congenital-heart-disease