Definition and Scope of Cardiac Transplant Medicine
Cardiac (heart) transplantation is a surgical treatment option for patients who have end-stage heart failure that is unresponsive to optimum pharmaceutical therapy.
A cardiac transplant is performed by a cardiovascular surgeon experienced in transplant. Heart failure and transplant cardiologists work intimately with cardiovascular surgeons who perform the cardiac transplants. Initial eligibility for transplant is handled by the heart-failure cardiologist who manages heart failure patients, ranked in increasing severity of their disease from Class I to Class IV.
Cardiac Transplant Medicine Associated Medical Specialities
Medical specialties related to cardiac transplant medicine include:
Infectious Diseases
Common Diseases and Medical Procedures
Cardiac transplant is recommended in patients with end-stage heart failure (advanced heart failure) who are unresponsive to drug therapy and lifestyle modifications. In such patients, interventional cardiology procedures and open-heart surgeries are not able to improve the function of the heart or alleviate the symptoms associated with heart failure. End-stage heart failure patients may experience symptoms even during rest. Several cardiovascular conditions can lead to advanced heart failure. Common conditions that can cause end-stage heart failure include:
Myocardial infarction: Myocardial infarction occurs due to sudden, complete blockage of one or more coronary arteries that supply blood to the heart. It may also result if a coronary artery is too narrow and has poor blood flow. Due to insufficient blood supply, necrosis (death of cells) of the heart tissue results. The most common cause of a heart attack is atherosclerosis—when build-up of cholesterol and fatty deposits within a coronary artery narrows it and disrupts the blood flow to the cardiac tissue itself. A thrombosis (blood clot) may add to the atherosclerosis and result in the final occlusive episode.
Heart valve disease: The valves of the heart help regulate blood flow within the heart. When the valves become faulty, blood flow is disrupted. If there is valve narrowing (stenosis), the blood flow inside the heart slows down. If a heart valve does not close properly (called prolapse), there is backward flow of blood (regurgitation). When the efficiency of the heart, measured by ejection fraction, is compromised, the body (and the heart itself) is underperfused. If severe, death will occur.
Cardiac arrhythmias: Abnormal or irregular heartbeat is known as cardiac arrhythmia. Common types of arrhythmias are atrial fibrillation, atrial flutter, ventricular tachycardia, ventricular fibrillation, and premature ventricular contractions. These can lead to heart failure.
Viral infection of the pericardium: The pericardium is a thin, sac-like membrane covering the heart. Pericarditis is the infection of the pericardium due to bacteria, virus, or fungi. Destruction of cardiac tissue can result in heart failure.
Cardiomyopathy: Enlargement of the heart muscle is called cardiomyopathy which can be dilated, hypertrophic, or restrictive. Cardiomyopathy causes heart muscle to become stiff and thick. This may be secondary to heart attack, hypertension, infection, or amyloidosis.
Left Ventricular Hypertrophy/Pulmonary Hypertension: Left ventricular hypertrophy (LVH) is often associated with left heart failure with pulmonary hypertension resulting primarily from passive backflow, causing elevated left-sided filling pressures.
Heart Transplantation:
Prior to the heart transplant surgery, preoperative management is the province of the heart failure cardiologist. Extensive monitoring is required. Depending on the complexity of a case, a heart transplant surgery can last anywhere from three to eight hours. The three main steps in the procedure are as follows:
First, the heart is connected to a heart-lung machine which performs the functions of the heart and takes the strain off the lungs. The machine pumps oxygen-rich, filtered blood into the body.
Then, the diseased heart is removed.
The diseased heart is replaced with the donor heart.
Following transplant surgery, the patient is put on anti-rejection drugs immediately in order to protect the transplanted heart from the action of the immune system. As the donor heart is foreign tissue, the immune system will try to fight it. Anti-rejection drugs will be required for the rest of the patient’s life to prevent this from happening. The post-transplant management of a patient involves these steps:
Monitoring organ rejection
Infection control
Coughing and breathing exercises to help to keep the lungs clear and prevent pneumonia
Medication adjustments based on the patient’s needs
Diet and exercise planning
Medical-Legal Cases Involving Cardiac Transplant Medicine
A heart transplant is associated with many risk factors. Errors in the pre- or post-transplant phase can also lead to legal issues for the heart failure cardiologist. Malpractice claims associated with cardiac transplant may include the following:
Recommending cardiac transplant in patients who do not need it and could be managed by conventional treatment methods
Failure to match organs correctly leading to organ rejection
Failure to correctly manage the patient in heart-failure
Secondary pulmonary issues
Common complications associated with a heart transplant are listed below.
Perioperative and postoperative bleeding
Postoperative infections
Blood clots, specifically pulmonary emboli and stroke
Preoperative clearance failures
Kidney failure during transplant surgery
Failure of the donor heart