Normally, there are 4 pulmonary veins that carry pure blood from both lungs that finally drains into left atrium (LA).
When instead of connection into left atrium, it connects elsewhere, named as TAPVC. Generally, it forms a chamber behind LA and that chamber connects at several sites and re-enter into right sided cardiac chambers.
This means that pure blood does not enter the body and so survival will not be possible without any communication in heart. Normally there is connection in the form of PFO or ASD between upper chambers of heart so that mixing of blood occurs at that level.
Varieties of TAPVC:
Supracardiac: When pulmonary veins drain above the heart and then into right side of heart (e.g. draining into SVC)
Cardiac: When pulmonary veins drain into the right heart directly
Infracardiac: When pulmonary veins drain below the heart and finally drain into right sided heart. Majority of this variety is obstructive in nature so patient becomes very symptomatic early after birth.
Mixed TAPVC: Any of combination mentioned above.
TAPVC can be obstructive or non-obstructive. If obstructive, patient will be symptomatic early.
Clinical presentation of TAPVC?
- It depends on the connection for mixing in heart.
- If PFO is small, then will be in respiratory distress with early cyanosis (blueness).
- If size is adequate then patient will be asymptomatic in early life.
- In case of obstruction, pulmonary pressures will be high so patient needs to treat early. In case of TAPVC, lungs receive double amount of blood supply so lung pressures can be little high even without obstruction.
Treatment of TAPVC?
- Only option is to correct this problem is by open heart surgery.
- By surgery, we will connect the common chamber with left atrium along with closure of hole.
Coronary sinus TAPVC