Operations to treat heart malformations or heart defects are performed through a hole in the cardiac septum. This surgery is used to repair defects of the atrial septum or the ventricular septum, or to correct an irregular connection between the heart and the pulmonary vein. There are a variety of treatments available, such as a heart catheter procedure, minimally invasive surgery or open heart surgery.
Some people are born with heart malformations or heart defects, or they may develop them later in life. The most common acquired heart malformations affect the heart valves. Operations involving the heart valves are described in the heat valve operations section.
Congenital defects, i.e. malformations that people are born with, are much more varied and range from insignificant defects that exhibit no major symptoms through to severe malformations that require heart surgery. Congenital defects are often only discovered after the person reaches adulthood. The most common malformations that require surgical correction include atrial septal defects, ventricular septal defects and anomalous pulmonary venous connections.
Atrial septal defect, ventricular septal defect
The heart is composed of a left part and a right part, which are separated by the cardiac septum. Before birth, a baby’s cardiac septum is still open at the foramen ovale and blood flows freely through the gap. After the baby is born, the foramen ovale closes and the blood flows through the lungs from the right to the left part of the heart. If the foramen ovale does not fully close, or the septa are somehow not properly sealed, this is called an atrial septal defect or a ventricular septal defect. Over time this can lead to cardiac insufficiency, in which case it becomes necessary to surgically close the defective septum. Depending on the size and location of the hole in the cardiac septum, the closure is performed using surgery or a heart catheter procedure.
What preparations are carried out before the procedure?
Before the procedure, the exact size and location of the defect is established using an ultrasound examination, heart catheter examination or magnetic resonance imaging (MRI). The results are then used to decide whether the hole can be closed by means of a heart catheter procedure, or whether open heart surgery is required. Children usually receive a general anaesthetic for heart catheter procedures, while for adults, it is sufficient to simply numb the injection site where the catheter will be inserted using a local anaesthetic.
How is the operation performed?
For a heart catheter procedure, a catheter featuring two occluders is inserted into the femoral vein in the patient’s groin and pushed through until it reaches the septal defect. The occluders are then positioned on each side of the cardiac septum, thereby closing the hole. In the case of a ventricular septal defect, an additional catheter is sometimes also inserted via a vein in the patient’s neck.
In the event of open heart surgery, the heart is accessed by separating the breastbone. During the operation, the heart is temporarily immobilised with the help of a special liquid solution (cardioplegia) and the patient’s circulation is maintained using a life-support machine. The defect is either stitched closed or sealed with a patch made from plastic or tissue from the patient’s pericardium. After the cardioplegic solution has been flushed out, the heart automatically starts beating again.
In the last few years, it has become possible (in certain circumstances) to perform the operation using a minimally invasive surgical technique known as a mini thoracotomy, which does not involve separating the breastbone and opening the ribcage.
What is the success rate of this procedure?
After the gap between the left and right parts of the heart has been closed, the patient is considered to have a healthy heart, as long as the heart did not suffer any permanent damage.
What are the possible complications and risks of this procedure?
Overall, complications following heart malformation surgery are rare. Occasionally patients experience temporary cardiac arrhythmias. As with all surgery, the operation may lead to complications such as infections, post-operative haemorrhaging and blood clots (thromboses) in rare cases.
What happens after the operation?
People who have undergone this operation should avoid lifting heavy objects and major physical exertion until their wounds have fully healed. After the operation, the patient’s heart function is checked regularly over an extended period of time.
After the operation, it is necessary to take blood-thinning medication for a few months, so that blood clots do not form on the implants. Patients are also prescribed antibiotics for a certain period of time to prevent infections. From then on, antibiotics should be taken as a preventative measure whenever they are at risk of infection, for instance due to dental work.
Anomalous pulmonary venous connection
The pulmonary veins that transport blood enriched with oxygen are normally connected to the left atrium. If this connection is irregular, either individual veins (partial anomalous pulmonary venous connection) or all four pulmonary veins (total anomalous pulmonary venous connection) are connected to the heart’s right atrium instead. Total anomalous pulmonary venous connections (TAPVC) must be surgically corrected immediately after birth; otherwise, the body will not be supplied with oxygen.
Partial anomalous pulmonary venous connections (PAPVC) only need to be corrected if they cause problems or if the patient also suffers from another heart defect. Patients with PAPVC often also have an atrial septal defect. Compared to atrial and ventricular septal defects, anomalous pulmonary venous connections are very rare heart malformations.
During surgery, the pulmonary veins are transplanted to their correct position on the left atrium. The operation takes place under general anaesthetic and requires a life-support machine.
After the operation, patients can generally led a normal life. However, they require regular cardiological check-ups and need to take antibiotics to prevent endocarditis (inflammation of the inner layer of the heart).