In total anomalous pulmonary venous return, the pulmonary veins do not connect to the left atrium. Instead, the entire pulmonary venous return enters the systemic venous circulation through a variety of connections. If there is no obstruction to pulmonary venous return, cyanosis is mild and heart failure develops within the first 2 to 4 wk of life. Severe obstruction of the pulmonary venous return may occur, resulting in severe neonatal cyanosis, pulmonary edema, and pulmonary hypertension. Diagnosis is by echocardiography. Surgical repair is required.

Total anomalous pulmonary venous return (see Fig. 10: Congenital Cardiovascular Anomalies: Total anomalous pulmonary venous return.) accounts for 1 to 2% of congenital heart anomalies. The clinical manifestation depends on the connection between the pulmonary venous confluence and the right side of the circulation. The most common types include

• Return via an ascending left vertical vein that drains to the innominate vein
• A descending vein that drains infradiaphragmatically to the portal circulation
• Connection of the confluence to the coronary sinus

The infradiaphragmatic drainage type is invariably severely obstructed, leading to dramatic pulmonary edema and cyanosis unresponsive to O₂. The other 2 types do not typically involve obstruction and lead to heart failure (HF) and mild cyanosis in the first month of life.

Fig. 10
Total anomalous pulmonary venous return. The pulmonary veins do not connect to the left atrium; instead, the entire pulmonary venous return enters systemic venous circulation through various connections. Systemic blood flow depends on right-to-left atrial shunting. AO = aorta; IVC = inferior vena cava; LA = left atrium; LV = left ventricle; PA = pulmonary artery; PV = pulmonary veins; RA = right atrium; RV = right ventricle; SVC = superior vena cava.

Symptoms and Signs

Neonates with obstructed pulmonary venous return present with severe pulmonary hypertension, pulmonary edema, and cyanosis. Physical examination usually shows a parasternal lift and a single, loud 2nd heart sound (S₂), with no significant murmur.

If pulmonary venous return is not obstructed, symptoms of HF are prominent and physical examination detects a hyperdynamic precordium, a loud and split S₂, and a grade 2 to 3/6 systolic ejection murmur audible along the left sternal border. A mid-diastolic tricuspid flow murmur may be audible at the lower left sternal border.

Diagnosis

• Chest x-ray and ECG
• Echocardiography

Diagnosis is suspected by chest x-ray and established by 2-dimensional echocardiography with color flow and Doppler studies. Cardiac catheterization is rarely necessary; occasionally, cardiac MRI or CT angiography may need to be done to better delineate the anatomy of pulmonary venous return.

Chest x-ray shows a small heart and severe diffuse pulmonary edema when there is pulmonary venous obstruction; otherwise, there is cardiomegaly with increased pulmonary vascular markings. ECG shows right axis deviation, right ventricular hypertrophy, and occasionally right atrial enlargement.

Treatment

• Surgical repair
• Medical treatment of HF (eg, diuretics, digoxinSome Trade Names
  DIGITEK
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  , ACE inhibitors) before surgery

Neonates with infradiaphragmatic return with obstruction require emergent surgical repair. In older infants, HF should be treated, followed by surgical repair as soon as the infant is stabilized.

Surgical repair consists of creating a wide anastomosis between the pulmonary venous confluence and the posterior wall of the left atrium, along with ligation of the vein decompressing the confluence into the systemic venous circulation. The repair is different for return to the coronary sinus, in which case the coronary sinus is unroofed into the left atrium and its opening to the right atrium is closed.

Endocarditis prophylaxis is recommended preoperatively but is required only for the first 6 mo after repair unless there is a residual defect adjacent to a surgical patch or prosthetic material.

Last full review/revision March 2010 by Lee B. Beerman, MD

Content last modified February 2012