Total Anomalous Pulmonary Venous Return

Total Anomalous Pulmonary Venous Return (TAPVR)
Definition What is total pulmonary venous return?
The blood returning to the heart from the body is low in oxygen since the body tissue extracted oxygen from the blood, such a poorly oxygenated blood is blue in color. The right pumping chamber of the heart (right ventricle) pumps blood to the lungs to become rich in oxygen again and acquire a pink color. This well oxygenated blood return to the heart through four pulmonary veins, two veins from each lung, which connect to the left atrium. In this heart defect the pulmonary veins return to the heart connecting to other than the left atrium. This abnormal connection may be in many different ways. The most commonly encountered abnormal connection is when all pulmonary veins meet together and drain into a single blood vessel which join the major vein draining poorly oxygenated blood from the upper part of the body (superior vena cava or SVC). In other scenarios the pulmonary veins may meet into a single vein which may drain into the blood circulation of the liver, or drain into the blood vessel which drains blood from the heart (coronary sinus).	The pulmonary veins collect behind the left atrium and instead of draining into the left atrium it drains into a vertical vein which drains into the superior vena cava (SVC) through the innominant vein.
Incidence How common or rare is this disease?
It occurs in 0.056 per 1,000 live births. It is the 12th most common congenital heart disease and constitutes 2.6% of patients with congenital heart disease.
Effects What does it cause?
When all or most of the pulmonary veins drain in this abnormal fashion, this would result in the well oxygenated blood returning from the lungs to mix with the poorly oxygenated blood returning from the body, this will occur in the right atrium. Part of this blood will proceed to the right ventricle through the tricuspid valve and the rest will cross the atrial communication that all children are born with to go to the left atrium and consequently to the left ventricle and out to the body. The mixture of the two types of blood will cause the blood going out to the body to become bluish in color (cyanosis), and there will also be an increase in the amount of blood flow to the lungs resulting in lung congestion and heart failure.	The well oxygenated blood returning from the pulmonary veins can not be delivered directly to the body as it normally does. Instead it mixes with the poorly oxygenated blood (blue) returning from the body resulting in cyanosis (purple).
Course How would this disease progress?
Lung congestion and heart failure start few days to weeks after birth. This may cause the child to feed poorly and grow inadequately. Untreated, bluish discoloration of the skin will progress and damage to the blood vessels of the lungs may eventually become irreversible.
Treatment Does it require any treatment?
Surgical repair is necessary for survival. The pulmonary veins are reconnected to the left atrium and the communication between the two atria is closed. This is performed within the first weeks after the child’s birth.
Complications
Surgical results are typically very good and children lead thereafter normal lives. However, occasionally the pulmonary veins are small and there may be obstruction to their entrance into the left atrium causing high blood pressure in the lungs. This may be relieved in the cardiac catheterization by placing a wire mesh tube (stent) which keeps the pulmonary vein open.