Index
Total Anomalous Pulmonary Venous Return
What Is Total Anomalous Pulmonary Venous Return?
Total Anomalous Pulmonary Venous Return, also known as Total Anomalous Pulmonary Venous Return, is a rare
cyanotic congenital heart defect in which all four pulmonary veins are malpositioned and make anomalous connections to
the systemic venous circulation. (Normally, pulmonary veins return oxygenated blood from the lungs to the left atrium
where it can then be pumped to the rest of the body). A patent foramen ovale, patent ductus arteriosus or an atrial septal
defect must be present, or else the condition is fatal due to a lack of systemic blood flow.
There are four variants: Supracardiac (50%): blood drains to one of the innominate veins (Brachiocephalic Veins) or the superior vena cava; Cardiac (20%), where blood drains into coronary sinus or directly into right atrium; Infradiaphragmatic (20%), where blood drains into portal or hepatic veins; and a mixed (10%) variant.
TAPVC can occur with obstruction, which occurs when the anomalous vein enters a vessel at an acute angle and can cause pulmonary venous hypertension and cyanosis because blood cannot enter the new vein as easily.
There are four variants: Supracardiac (50%): blood drains to one of the innominate veins (Brachiocephalic Veins) or the superior vena cava; Cardiac (20%), where blood drains into coronary sinus or directly into right atrium; Infradiaphragmatic (20%), where blood drains into portal or hepatic veins; and a mixed (10%) variant.
TAPVC can occur with obstruction, which occurs when the anomalous vein enters a vessel at an acute angle and can cause pulmonary venous hypertension and cyanosis because blood cannot enter the new vein as easily.
What Causes Total Anomalous Pulmonary Venous Return?
The cause of total anomalous pulmonary venous return is unknown.
In normal circulation, blood is sent from the right ventricle to pick up oxygen in the lungs. It then returns through the pulmonary (lung) veins to the left side of the heart, which sends blood out through the aorta and around the body.
In TAPVR, oxygen-rich blood returns from the lungs to the right atrium or to a vein flowing into the right atrium, instead of the left side of heart. In other words, blood simply circles to and from the lungs and never gets out to the body.
For the infant to live, an atrial septal defect (ASD) or patent foramen ovale (passage between the left and right atria) must exist to allow oxygenated blood to flow to the left side of the heart and the rest of the body.
How severe this condition is depends on whether the pulmonary veins are blocked or obstructed as they drain. Obstructed TAPVR causes symptoms early in life and can be deadly very quickly if it is not found and corrected with surgery.
In normal circulation, blood is sent from the right ventricle to pick up oxygen in the lungs. It then returns through the pulmonary (lung) veins to the left side of the heart, which sends blood out through the aorta and around the body.
In TAPVR, oxygen-rich blood returns from the lungs to the right atrium or to a vein flowing into the right atrium, instead of the left side of heart. In other words, blood simply circles to and from the lungs and never gets out to the body.
For the infant to live, an atrial septal defect (ASD) or patent foramen ovale (passage between the left and right atria) must exist to allow oxygenated blood to flow to the left side of the heart and the rest of the body.
How severe this condition is depends on whether the pulmonary veins are blocked or obstructed as they drain. Obstructed TAPVR causes symptoms early in life and can be deadly very quickly if it is not found and corrected with surgery.
What are the Signs & Symptoms of
Total Anomalous Pulmonary Venous Return?
- Cardiomegaly,
- Cottage-loaf Sign, that is, Chest X-ray appearance similar to a cottage loaf, also known as the ‘snow man’ sign or ‘figure of 8’ sign.
- Fixed Split S2,
- Loud S1,
- Right Ventricular heave,
- Right axis deviation on ECG,
- Right Ventricular Hypertrophy,
- S3 Gallop,
- Snowman sign or `figure of 8 configuration` on chest radiograph,
- Systolic ejection murmur at left upper sternal border,
- Tachypnea, Cyanosis, Dyspnea since the overloaded pulmonary circuit can cause pulmonary edema,
- Cottage-loaf Sign, that is, Chest X-ray appearance similar to a cottage loaf, also known as the ‘snow man’ sign or ‘figure of 8’ sign.
- Fixed Split S2,
- Loud S1,
- Right Ventricular heave,
- Right axis deviation on ECG,
- Right Ventricular Hypertrophy,
- S3 Gallop,
- Snowman sign or `figure of 8 configuration` on chest radiograph,
- Systolic ejection murmur at left upper sternal border,
- Tachypnea, Cyanosis, Dyspnea since the overloaded pulmonary circuit can cause pulmonary edema,
HEART CONDITIONS Diseases and Treated FAQ's
Prenatal diagnosis: Anomalous pulmonary venous return can be diagnosed before birth by a
fetal echocardiogram or heart ultrasound as early as 18 weeks into the pregnancy.
It can be diagnosed with CT scan, angiography, transesophageal echocardiography, or cardiac MRI. Unfortunately, less invasive and expensive testing, such as transthoracic echocardiography and CT scanning are generally less sensitive.
A chest X-ray, similarly, will show enlargement of the right side of the heart and will also demonstrate increased blood flow into the pulmonary vessels. In newborns with total anomalous pulmonary venous return and obstructed pulmonary venous return, chest X-ray may show evidence of pulmonary edema (fluid in the lungs)
Measurement of oxygen saturation may detect a low value (typically in the mid- to high 80s) in children without pulmonary venous obstruction. An electrocardiogram (ECG) may be helpful to show if there are problems with enlargement of the heart.
It can be diagnosed with CT scan, angiography, transesophageal echocardiography, or cardiac MRI. Unfortunately, less invasive and expensive testing, such as transthoracic echocardiography and CT scanning are generally less sensitive.
A chest X-ray, similarly, will show enlargement of the right side of the heart and will also demonstrate increased blood flow into the pulmonary vessels. In newborns with total anomalous pulmonary venous return and obstructed pulmonary venous return, chest X-ray may show evidence of pulmonary edema (fluid in the lungs)
Measurement of oxygen saturation may detect a low value (typically in the mid- to high 80s) in children without pulmonary venous obstruction. An electrocardiogram (ECG) may be helpful to show if there are problems with enlargement of the heart.
In TAPVC without obstruction, surgical redirection can be performed within the first month of life.
The operation is performed under general anesthesia. The four pulmonary veins are reconnected to the left atrium, and any associated heart defects such as atrial septal defect, ventricular septal defect, patent foramen ovale, and/or patent ductus arteriosus are surgically closed. With obstruction, surgery should be undertaken emergently.
PGE1 should be given because a patent ductus arteriosus allows oxygenated blood to go from the circulation of the right heart to the systemic circulation.
Total anomalous pulmonary venous return is a defect which requires surgical correction. The timing of the surgical repair varies depending on the type of total anomalous pulmonary venous return present as well as the condition of the child.
Surgical repair is performed emergently for newborns with obstructed total anomalous pulmonary venous return.
Some of these children will actually require extracorporeal life support (ECMO) prior to surgery because of their blood flow instability.
Children with total anomalous pulmonary venous return without obstruction typically undergo surgical repair electively days to weeks after the diagnosis.
The operation is performed under general anesthesia. The four pulmonary veins are reconnected to the left atrium, and any associated heart defects such as atrial septal defect, ventricular septal defect, patent foramen ovale, and/or patent ductus arteriosus are surgically closed. With obstruction, surgery should be undertaken emergently.
PGE1 should be given because a patent ductus arteriosus allows oxygenated blood to go from the circulation of the right heart to the systemic circulation.
Total anomalous pulmonary venous return is a defect which requires surgical correction. The timing of the surgical repair varies depending on the type of total anomalous pulmonary venous return present as well as the condition of the child.
Surgical repair is performed emergently for newborns with obstructed total anomalous pulmonary venous return.
Some of these children will actually require extracorporeal life support (ECMO) prior to surgery because of their blood flow instability.
Children with total anomalous pulmonary venous return without obstruction typically undergo surgical repair electively days to weeks after the diagnosis.
The complications of TAPVR include:
- Enlarged heart, Lung problems, including respiratory failure and high blood pressure in the lungs, abnormal heart rhythms.
- Risk factors thought to be related to this condition include:
- Family history of heart defects,
- Having other heart defects,
- Environmental exposures,
More research is needed to confirm causes and risk factors for TAPVC.
- Enlarged heart, Lung problems, including respiratory failure and high blood pressure in the lungs, abnormal heart rhythms.
- Risk factors thought to be related to this condition include:
- Family history of heart defects,
- Having other heart defects,
- Environmental exposures,
More research is needed to confirm causes and risk factors for TAPVC.