What is a Heart Transplant?
Heart transplant is a simple three step procedure. This is a rather simple procedure for a cardiac surgeon compared to other complicated surgeries.
First Step:
Harvesting organ from the donor:
The donor is usually a brain dead person on life support. When the family of such a person is willing to donate the organ, the organ is removed and protected in ice to prevent any damage. A heart once removed from the body stays stable for about 6 hours. Due to time constraints the Heart is usually flown down if the transplant has to be conducted interstate. The Tamil Nadu police offer support in such cases if the Heart has to be taken from one part of the city to the other. The areas are cordoned off immediately on request. Procuring a heart itself is a very structured and transparent process with the help of the government. The heart usually goes to such a recipient who needs it most.
Removing the recipient’s damaged heart:
The second step is removing the damaged heart. This is a very simple procedure if the recipient has not undergone any previous surgeries. In case the recipient has undergone a Bypass or a catheter implant then cutting through the scar tissue may prolong or complicate this step.
Implantation of the donor heart: The third step is probably the easiest; the implantation of the donor heart. Today, this operation basically involves the creation of only five lines of stitches, or “anastomoses”. These suture lines connect the large blood vessels entering and leaving the heart. Remarkably, if there are no complications, most patients who have had a heart transplant are home about one week after the surgery. The generosity of donors and their families makes organ transplant possible.
Who needs a Heart transplant?
Most patients require a transplant because their hearts can no longer pump well enough to supply blood with oxygen and nutrients to the organs of the body. A smaller number of patients have a good pump, but a bad “electrical conduction system” of the heart. This electrical system determines the rate, rhythm and sequence of contraction of the heart muscle. There are all kinds of problems that can occur with the conduction system, including complete interruption of cardiac function causing sudden cardiac death.
While there are many people with “end-stage” heart disease with inadequate function of the heart, not all qualify for a heart transplant. All the other important organs in the body must be in pretty good shape. Transplants cannot be performed in patients with active infection, cancer, or bad diabetes mellitus; patients who smoke or abuse alcohol are also not good candidates. It’s not easy to be a transplant recipient. These patients need to change their lifestyle and take numerous medications (commonly more than 30 different medications). Hence, all potential transplants patients must undergo psychological testing to identify social and behavioral factors that could interfere with recovery, compliance with medications, and lifestyle changes required after transplantation.
Moreover, needing a heart and being a suitable candidate are not enough. The potential donor heart must be compatible with the recipient’s immune system to decrease the chance of problems with rejection. Finally, this precious resource, the donor organ, must be distributed fairly. The Multi Organ Harvesting Aid Network makes sure that the sickest recipient is given the first preference. As mentioned earlier, this organization makes sure the entire process is fair, structured and transparent.
Results of a Heart Transplant:
In patients with severe heart failure that requires transplantation, the mortality rate within one year is 80%. Five year survival in patients with any form of complex heart disease and heart failure is 50%.
After heart transplant, the one year survival rate averages 90% and five year transplant averages 60%.
Complications of a heart transplant:
The immune system of the body fights against the implanted organ as it sees it as a foreign body. Rejection can be controlled with powerful immunosuppressive medications that greatly reduce the chances of complete organ rejection. Even while there is no active rejection, there is a possibility of acute chronic rejection which causes the growth of tissues in heart vessels. This eventually leads to blockage and finally the organ fails to pump. This is the main factor why heart transplant does not have good long term results.
Immunosuppressive drugs greatly reduce the chances of rejection but also increase the chances of infection in the recipient. The recipient is prone to the most common infections and some may eventually die of developing cancer.
How does a heart transplant patient know if he or she is rejecting the donor organ or developing an infection?
Symptoms
- Weakness,
- Fatigue
- malaise (feeling lousy),
- fever, and
- “flu-like symptoms”, such as chills, headaches, dizziness, diarrhea, nausea and/or vomiting.
In such cases, the recipient has to immediately seek medical attention and perform all required tests so that it can be treated appropriately.
How is rejection of the organ diagnosed and monitored?
The standard for monitoring rejection is the endomyocardial biopsy. This is a simple operation for the experienced cardiologist and can be done as an outpatient procedure. First, a catheter is put into the jugular vein in the neck. From there, the catheter is advanced into the right side of the heart (right ventricle) using an x-ray method called fluoroscopy for guidance. The catheter has a bioptome at its end, a set of two small cups which can be closed to pinch off and remove small samples of heart muscle. The tissue is processed and placed on glass slides to be reviewed under the microscope by a pathologist. Based on the findings, the pathologist can determine whether or not there is rejection.
Immunosuppressive therapy is then adjusted, for example, increased if rejection is present. Investigators have tried to develop less invasive methods to monitor for rejection. There is a new high-tech analysis that can be done in a sample of blood that is very promising and much easier for the patient than the endomyocardial biopsy. This test looks at the expression of specific genes in cells in the blood. The amount of expression of key genes indicates whether or not rejection is occurring. Nevertheless, so far, no method has replaced the endomyocardial biopsy.
Several theories exist to explain the link between periodontal disease (Periodontal disease is a type of disease that affects one or more of the periodontal tissues: 1. alveolar bone, 2. periodontal ligament, 3. cementum, 4. gingiva) and heart disease. One theory is that oral bacteria can affect the heart when they enter the blood stream, attaching to fatty plaques in the coronary arteries (heart blood vessels) and contributing to clot formation. Coronary artery disease is characterized by a thickening of the walls of the coronary arteries due to the buildup of fatty proteins. Blood clots can obstruct normal blood flow, restricting the amount of nutrients and oxygen required for the heart to function properly. This may lead to heart attacks.
