09 July 2018
Episode 9- Dr WALT LILLEHEI
Born in Minnesota, Dr. Lillehei completed his Ph.D. in surgery at the University of his hometown in 1951.
At this time, the medical world is still looking for a technique to perform open-heart surgery, while allowing vital organs to receive oxygen. Stopping hypothermic circulation leaves the surgeons only a few minutes to perform the operation. This short time, however, does not allow for more complex surgeries. Dr. Lillehei will form a group to try to solve this problem.
The initial idea is nourished by the fact that a fetus receives oxygen from the circulation of its mother. The pulmonary function is then bypassed as all exchanges done in the placenta.
The placenta is a highly vascularized structure and is attached to the uterus. Veins and arteries stick out, which allows connecting to the fetus. The placenta collects carbon dioxide (CO2) from the fetus and gives oxygen to the fetal blood.
What works in the womb should work well outside this one!
They come up with the idea of connecting a child with a congenital heart defect to his mother or father while the surgeon performs the surgery.
The group therefore buys plastic tubes and a pump that works by circular compression. A wheel rotates and compresses the blood-filled tube in a circular motion with adjustable speed to push the blood forward. In this way, there is no contact with the blood and the tubes are discarded after use.
They experiment with two dogs: a donor and a receiver. The dogs are asleep and the pump is turned on for 30 minutes.
All blood that reaches the heart of the donor is then deviated to a vein of the receiver. The heart of the donor stops and heart surgery is possible at this time. The oxygenated blood of the receiver returns through one of its arteries to the "patient" that they are operating. When the dogs wake up, they are doing well. The intervention is described as successful!
The experiment does not end here. They create a model to perform this type of surgery. A hole between the two ventricles is practiced in a dog. The donor dog is installed. The pump connects the two dogs and the complete surgery is performed in 24 minutes. Once again, the experience went well.
In March 1954, Dr. Lillehei scheduled the first repair of the interventricular septum.
Gregory Gitten, barely 2 years old, is scheduled to close this communication. The controversy breaks out however. A debate on ethics is launched. This technique compromises the lives of two people. The mortality risks can be 200%.
Dr. Lillehei finds the necessary support so that the hospital accepts that the surgery is practiced. The procedure is as planned. Interventricular communication (IVC) is repaired and the young patient is well, as is his recipient mother.
The rest of the operation, however, does not go as well. Gregory will be swept away by pneumonia two weeks after the procedure.
Shortly afterwards, the parents of Annie Brown, 4 years old, ask for a consultation with Dr. Lillehei. The young girl is a carrier of this congenital anomaly. At each contraction of her heart, part of the blood passes through the right ventricle and returns to the lungs. This creates a volume overload in the pulmonary circulation with catastrophic effects in the short or medium term, depending on the size of the hole.
Annie Brown is destined for a very short life. She is hospitalized multiple times for pneumonia. Blood compatibility is present only with the father, who is designated a donor. The operation takes place after a first remission due to pneumonia.
The intervention begins and the heart is opened, allowing the access to the hole and thus closing the septum of the ventricles. At the closing of the heart, the contractions will resume, but at a too slow rate. An atrioventricular conduction blockage occurs. The cause could be a jamming of the electrical passage at this level by the suture. The cardiostimulator (more commonly known as the pacemaker) does not exist at this time. The electrical passage resumes spontaneously, after 90 long seconds.
Annie and her father wake up without any apparent problems. The consequences of the operation are without event and Annie leaves for the house thereafter.
In the next 9 weeks, 7 patients are operated using this method. Of these patients, 6 died and one recipient had a stroke caused by an air bubble in the brain.
Despite all these obstacles, he will correct the first tetralogy of Fallot, a complex congenital disease. The "cross traffic" is still removed. Another way of doing things must still be found.
Dr Lillehel died on July 5, 1999 at the age of 80.