Heart-Lung Transplantation

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Heart-Lung Transplantation

Definition
Purpose
Demographics
Description
Diagnosis/Preparation
Aftercare
Risks
Normal results
Morbidity and mortality rates
Alternatives

Definition

Heart-lung transplantation is the surgical replacement of a person’s severely diseased or dysfunctional heart and lungs with a healthy human donor heart and lungs.

Purpose

Heart-lung transplantation is an uncommon operation. It is performed when the person has both end-stage lung disease and end-stage heart disease that

do nor respond to any other medical treatments. It is also sometimes performed on children with severe congenital heart defects. The purpose of heart transplantation is to extend and improve the life of a person who would otherwise die.

Demographics

Heart-lung transplant recipients are not limited by sex, race, or ethnicity. Patients who are severely limited in daily activity, as defined by their doctors, and have a very limited life expectancy, may be candidates for heart-lung transplantation. Healthy donor hearts and lungs are in short supply, therefore, strict rules dictate criteria for transplant recipients. Patients who may be too sick to survive the surgery or the side effects of immunosuppressive therapy are not considered transplant candidates. Other factors that absolutely contraindicate (rule out) heart-lung transplantation include multiple organ system dysfunction, current substance abuse, bone marrow failure, active malignancy (cancer), and HIV infection. Other relative contraindications include age greater than 60, anorexia, obesity, peripheral and coronary vascular disease, ventilator support, steroid dependency, chest wall deformity, resistant bacterial or fungal infections, and certain psychiatric conditions.

According to the Organ Procurement and Transplantation Network, in the United States 961 heart-lung transplants were performed between 1988 and November 2007. Overall, slightly more women than men have received heart-lung transplants in the United States, and more than 800 of the recipients were white. Internationally 800–1,000 heart-lung transplants are performed each year.

Description

Patients with end-stage heart and lung disease unresponsive to medical treatment must have a complete medical examination before they can be put on the transplant waiting list. Many types of tests are done, including blood tests, X-rays, and tests of heart, lung, and other organ function. The results of these tests indicate to doctors how serious the heart disease is and whether the patient is healthy enough to survive the transplant surgery.

Patient-donor matching

All patients placed on the waiting list are registered with the United Network for Organ Sharing (UNOS). UNOS has organ transplant specialists who run a national computer network that connects all the transplant centers and organ-donation organizations. Patients

KEY TERMS

Aorta— The main artery that carries blood from the heart to the rest of the body. The aorta is the largest artery in the body.

Cardiopulmonary bypass— Mechanically circulating the blood with a heart-lung machine that bypasses the heart and lungs.

Congenital defect— A defect present at birth that occurs during the growth and development of the fetus in the womb.

Coronary vascular disease— Or cardiovascular disease; disease of the heart or blood vessels, such as atherosclerosis (hardening of the arteries).

End-stage heart or lung failure— Severe heart or lung disease that does not respond adequately to medical or surgical treatment.

Nephrotoxicity— A building up of poisons in the kidneys.

Osteoporosis— Loss of bone mass, causing bones to break easil.

Pulmonary hypertension— Increased blood pressure in the blood vessels of the lungs.

Resistant infections— Infections that are not cured by standard antibiotic treatment.

are grouped in terms of priority based on how long they can live without a transplant. The list is national and independent of the heart transplant center where the surgery will take place.

Established criteria for donor organ matching include the following:

anatomic compatibility between the donor and recipient;
immunologic compatibility between the donor and recipient;
medical urgency; and
location of the patient and donor.

The heart and lungs must be transplanted as quickly as possible, therefore, after anatomic and blood group compatibility have been determined, a list of local patients is checked first for a suitable match. After that, a regional list and then a national list are checked. The patient’s transplant team of heart and lung transplant specialists makes the final decision as to whether a donor organs are suitable for the patient.

The transplant procedure

Under general anesthesia, an incision is made in the patient’s chest to access the heart and lungs. Anticoagulation (anti-clotting) and antibiotic medications are provided, and cardiopulmonary bypass to a heart-lung machine is established. Blood flow through the heart is stopped by application of a clamp across the aorta. The surgeon removes the diseased organs. In the heart, the back parts of the patient’s own right and left atriums are often left intact, along with the aorta beyond the coronary arteries. This provides large suture lines that allow decreased surgical time and result in fewer bleeding complications.

The donor heart is dissected to match the remaining native heart and aorta. The sutures are made to join the structures. Once completed, the cardiac chambers is filled with the patient’s blood that is diverted away from the heart and lung machine. Mechanical ventilation of the donor lungs helps inflate the lung tissue.

Diagnosis/Preparation

History, examination, and laboratory studies are performed before referral to a transplant center. These records are reviewed on-site for qualification to be placed on the United Network for Organ Sharing (UNOS) national waiting list. Procedures necessary for evaluation include a chest X-ray, arterial blood samples, air flow studies, ventilation and perfusion scanning (studies the exchange of oxygen with carbon dioxide in the lungs), and cardiac catheterization of both the right and left sides of the heart.

Aftercare

The patient will be treated in the intensive care unit upon completion of the surgery, and cardiac monitoring will be continued. Medications for cardiac support will be continued until cardiac function stabilizes. Mechanical circulatory support may be continued until cardiac and respiratory functions improve. Ventilator support will be continued until the patient is able to breathe independently. After leaving the intensive care unit, the patient will spend a week or more in a special transplant unit. Medications to prevent organ rejection will be continued indefinitely, as will medications to prevent infection. The patient will be evaluated before discharge and provided with specific instructions to recognize infection and organ rejection. The patient will be given directions to contact the physician after discharge along with criteria for emergency room care.

WHO PERFORMS THE PROCEDURE AND WHERE IS IT PERFORMED?

Cardiac surgeons and cardiovascular surgeons can be trained in transplantation surgery during their residency. Young adults and pediatric patients are treated at centers that specialize in the care of children.

Risks

General anesthesia and cardiopulmonary bypass carry certain risks unassociated with the heart-lung transplant procedure. Graft rejection and technical failure are often a result of lung injury sustained during the stoppage and restarting of the organ. Infection by cytomegalovirus (CMV) often occurs in the first year, but is usually treatable. Immunosuppressive drugs to prevent rejection have side effects associated with malignancies, lymphomas or tumors of the skin and lips being most common. Osteoporosis and nephrotoxicity are also associated with the immunosuppressive therapies.

Normal results

Lung and cardiac function are drastically improved after transplantation. Strenuous exercise may still be limited, but quality of life is greatly improved. The patient will continue with medical visits frequently throughout the first year, including required tissue biopsies to test for rejection and cardiac catheterizations. The frequency of medical visits will decrease after the first year, but invasive medical procedures will still be necessary. Medications to suppress rejection of the organs and prevent infection are continued.

Morbidity and mortality rates

Death within the first 30 days is usually associated with technical and graft failure of the transplanted organ. Causes of death after 30 days often include immune system rejection of the transplant, infection of the airways or other infection, and the development of coronary artery disease. The one-year survival rate is 65%. The five-year survival rate is 40%.

Systemic hypertension (high blood pressure) is common at one year after surgery and can be relieved with medical treatment. Chronic bronchiolitis (infection of the airways) is expected in one-third of patients

QUESTIONS TO ASK THE DOCTOR

How many of these procedures have been performed at this center in the last year and last five years?
How many of these procedures has the surgeon performed in the last year and last five years?
What is the length of time spent on the waiting list for a patient with the pathology of the patient?
What are the complications associated with this procedure?
What are the complications associated with the duration of the transplantation?
What type of limitations will be faced if the transplant is successful?
How frequent will future medical visits be after the procedure during the first year and after that?

at five years. Hyperlipidemia (high lipid concentration in blood), diabetes mellitus, and kidney dysfunction are also seen in some patients within the first year of transplantation and continue to affect an increasing number of patients each year. Malignancies that include lymphoma and lip and skin tumors are seen at a higher rate than in general populations.

Alternatives

There are no good alternatives when both heart and lungs are seriously diseased. Individuals with only end-stage heart disease sometimes do well with a ventricular-assist device that helps the heart pump. Individuals with end-stage lung disease but a healthy heart often do well with a lung transplant. When both organs are seriously diseased, there are few alternatives to a heart-lung transplant if a suitable donor can be found.