Basics
Description
- Total anomalous pulmonary venous connection (TAPVC) is a condition in which the pulmonary veins drain to a common pulmonary vein (CPV) that does not connect to the left atrium.
- TAPVCs are classified as:
- Supracardiac (45%): Retrograde blood flow from CPV to left superior vena cava (vertical vein) to innominate vein to the superior vena cava (SVC) to the right atrium; or less commonly, CPV direct to right SVC
- Intracardiac (25%): CPV to left SVC to coronary sinus
- Infradiaphragmatic (25%): CPV to inferior cardinal vein to portal system to liver to inferior vena cava (IVC) to right atrium
- Mixed (connections at two or more levels) (5%)
Epidemiology
Incidence
In autopsy series the incidence of TAPVCs varies from 1-5% of patients with congenital heart disease.
Risk Factors
Pregnancy should be well tolerated, following successful repair in childhood.
Genetics
There are limited data:
- Small chromosome translocations or a single autosomal gene mutation may be possible
Pathophysiology
- The CPV drains into one or more alternate channels (embryonic cardinal veins), which eventually reach the right atrium.
- Systemic blood flow is maintained by right-to-left blood flow across a foramen ovale or atrial septal defect to the left atrium.
- If the channels returning blood from the CPV to the systemic venous system are obstructed, a neonate presents in the first days of life with the picture of severe left heart obstruction (eg, mitral stenosis).
- If obstruction is mild, the infant will present later with high pulmonary blood flow, pulmonary HTN, and CHF.
- With no obstruction, a patient may present later in childhood with the clinical profile of a large atrial septal defect.
Associated Conditions
- 2/3 of TAPVCs exist as isolated lesions with an atrial communication.
- 1/3 are associated with other congenital heart lesions:
- Single ventricle
- Patent ductus arteriosus
- Truncus arteriosus
- Atrioventricular canal
- Hypoplastic left heart syndrome (HLHS)
- Transposition of the great vessels
- Pulmonary stenosis and/or atresia
- Heterotaxy syndrome with anomalies of the aortovisceral situs: Asplenia, right isomerism
- Absent morphologic left atrium and thus virtually always associated with TAPVCs via confluence to the right atrium, or right or left superior vena cava
- Associated noncardiac malformations include: Abdominal visceral heterotaxy, malrotation of the GI tract, and bilateral right lungs
Diagnosis
History
- Infants with severe obstruction of TAPVC:
- Present with cyanosis and/or respiratory distress shortly after birth or within the 1st few days of life.
- Obstruction usually occurs at the connection of the pulmonary venous channel to the systemic venous system (eg, portal vein, innominate vein, SVC, etc.), rarely at the atrial septum.
- In the infradiaphragmatic type, severe obstruction is usual when the chamber connects to the portal vein and the ductus venosus closes. It also may occur with supracardiac connections, especially when the common pulmonary vein connects directly to the right superior vena cava. With mild to moderate obstruction, the patient presents later in the 1st month or 2 of life with symptoms of heart failure:
- Dyspnea
- Difficulty feeding
- Failure to thrive
- Cyanosis with saturation of 80-85%
- Patients with nonobstructed TAPVC may escape detection in infancy and present later in childhood, similar to atrial septal defect. Such patients may be asymptomatic.
Physical Exam
- Loud murmurs are infrequent.
- Grade 1 or 2/6 short systolic pulmonic flow murmurs can occur.
- Pulses are normal.
- In the presence of severe pulmonary venous obstruction or a restrictive atrial communication in a neonate, there is decreased systemic output and low BP.
- Hepatomegaly
Tests
Lab
- Oximetry: Arterial oxygen saturation is often reduced to 85-90%; lower with obstruction. The umbilical venous saturation may be as high (90-100%), with infradiaphragmatic TAPVC to the portal system.
Imaging
- Radiography:
- CXR with pulmonary venous obstruction
- Evidence of a ground-glass appearance with a diffuse linear reticular pattern or pulmonary edema associated with Kerley B lines.
- Heart size is normal or small.
- CXR without severe pulmonary venous obstruction
- Heart is enlarged.
- Pulmonary vascular markings are increased.
- Supracardiac type may have a "snowman" appearance with TAPVCs to the SVC via a vertical vein to the left innominate vein. In the neonate this configuration may be obscured by thymus.
- Echo:
- Should be diagnostic for all types of TAPVCs with demonstration of the pulmonary venous confluence draining to the:
- Vertical vein (left SVC) to the left innominate vein, which drains to the right SVC and RA.
- Right SVC
- Coronary sinus or RA
- Portal system or to hepatic sinusoids below the diaphragm may be recognized by fetal echo.
- Pulmonary vein obstruction if Doppler flow acceleration >2 m/s
- MRI:
- Multiplane gated magnetic resonance imaging (MRI)in older patients can be useful if transthoracic or transesophageal echo is not diagnostic.
- Cardiac Catheterization:
- Generally not needed for isolated TAPVC in the newborn period. 2D echo, Doppler, and Doppler color studies are most often definitive.
- In the presence of pulmonary venous obstruction below the diaphragm, cardiac catheterization may delay surgical treatment and increase morbidity.
- May be necessary to evaluate associated cardiac or pulmonary disease
- Urgent balloon septostomy may be useful in rare cases when the atrial communication is restrictive and surgery must be delayed.
Surgery
ECG:
- Right axis deviation
- Right ventricular hypertrophy: QR in V3R or V1 or pure R waves in V3R are often present. Upright T waves in V1 and V3R are consistent with systemic pressure in the right ventricle.
- Left ventricular forces may be decreased.
Differential Diagnosis
- Newborn:
- Hypoplastic left heart syndrome
- Interrupted aortic arch or severe coarctation of the aorta
- Hypoplastic right heart syndromes (tricuspid and pulmonary atresia)
- Transposition of the great arteries
- Pulmonary vein stenosis or pulmonary vein atresia
- Cor triatriatum
- Persistent pulmonary HTN of the newborn (PPHN)
- Respiratory distress syndrome or hyaline membrane disease
- In older infants and children:
- Large atrial septal defect
- Common atrium
- Partial anomalous pulmonary venous return
Treatment
Medication
- Prostaglandin E1 to maintain patency of ductus arteriosus
- Diuretics in the presence of pulmonary venous congestion
- Nitric oxide in the presence of severe pulmonary artery HTN postoperatively
First Line
- Prostaglandin E1 at 0.03-0.1 μg/kg/min in rare cases
- Preoperative and postoperative extracorporeal membrane oxygenation (ECMO) may be used with severe pulmonary venous obstruction and pulmonary artery HTN
Second Line
- ECMO
- Postoperative use of nitric oxide may be used to treat severe pulmonary artery HTN.
Additional Treatment
General Measures
Infants with cyanosis or respiratory distress may require ventilator support:
- In rare instances, Prostaglandin E1 0.03-0.1 μg/kg/min IV may be required to maintain patency of the ductus arteriosus and thus maintain cardiac output.
- All types of TAPVCs are generally surgically corrected in the newborn period soon after diagnosis.
Surgery
- Establish connection of confluence of pulmonary veins (CPV) to the left atrium utilizing a generous left atrial anastomosis, usually with pericardial augmentation, as well as ligation of the common vertical vein.
- With prompt surgical intervention, mortality is low, especially with supracardiac and cardiac types (â¤10%).
- Surgical mortality is significantly higher when TAPVC is associated with complex lesions such as single ventricle, heterotaxy with atrial isomerism, and transposition of the great vessels.
In-Patient Considerations
Admission Criteria
Any patient diagnosed with a condition with or without obstruction should undergo surgical repair.
Ongoing Care
Follow-Up Recommendations
Patient Monitoring
Postoperatively patients should be monitored for:
- Early and late signs of pulmonary venous congestion and/or obstruction
- Pulmonary HTN
- Rhythm disturbances
- Pregnancy will be well tolerated in successfully repaired patients
Patient Education
- Full activities and a regular diet appropriate for age
- Patients should be followed by clinicians in a pediatric cardiology or adult congenital heart program.
- Activity:
Prognosis
- Prognosis for fully repaired isolated TAPVC usually is excellent. Patients remain asymptomatic without physical restrictions. Early or late postoperative problems could include the following:
- Obstruction at the anastomotic site or proximal within the pulmonary veins.
- Obstruction of intrapulmonary venules, causing pulmonary HTN.
- Pulmonary vein stenosis with medial hypertrophy may be present in utero and persist or progress postoperatively. These patients have increased morbidity and mortality.
- Pulmonary vein stenting has had limited success.
- Clinically important atrial arrhythmias may develop in some patients, including sinus bradycardia, supraventricular tachycardia, atrial flutter, and sinus node dysfunction. Ventricular arrhythmias are rare.
Complications
- Pulmonary venous obstruction
- Pulmonary artery HTN
Additional Reading
1Freedom RM, Mawson JB, Yoo S Congenital Heart Disease-Textbook of Angiocardiology. New York: Futura, 1997.2Garson AJr, Bricker JT, Fisher DJ The Science and Practice of Pediatric Cardiology, 2nd ed. Baltimore: Lippincott Williams & Wilkins, 1998.3Moss AJ, Adams FH, Heart Disease in Infants, Children and Adolescents, volume 2, Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins, 2008.4Stark J, deLeval M. Surgery for Congenital Heart Defects. New York: Grune & Stratton, 1983.5Hancock L, Farsen CL, Zurakawski D. Total anomalous pulmonary venous connection: An analysis of current management strategies in a single institution, Ann Thorac Surg 2005;79:595-606.6van Velde ME, Parness IA, Colan SD. Two dimensional chocardiography in the pre and post operative management of totally anomalous pulmonary venous connection. J AM Coll Cardiol 1991;18(7):1746-1751.
Codes
ICD9
747.41 Total anomalous pulmonary venous connection
SNOMED
111323005 total anomalous pulmonary venous return (disorder)