Heart transplantation is now considered to be a viable treatment option for selected patients with end-stage heart disease. At present, more than 4,000 heart transplants are done annually worldwide. The indications for adult heart transplantation, as reported to the Registry of the International Society for Heart and Lung Transplantation in 2013, are shown in Figure 13.1. Ischemic coronary artery disease (28.1%) and nonischemic cardiomyopathy (54.2%) represent the most frequent causes for transplantation.

It should be noted that indications/contraindications can be flexible and can vary from center to center.

Criteria for selection can include the following:

Contraindications (not necessarily absolute)

The limiting factor in heart transplantation is the shortage of donor organs. In Canada, there were 146 adult and 21 pediatric heart transplants performed in 2013, with 167 people on the waiting list at the end of that year. In the United States, 2,655 heart transplants were
performed in 2014, with over 4,000 patients on the waiting list. Following the diagnosis of brain death, organ procurement may be considered for the purpose of donation. Preferably, the donor should not have sustained prolonged cardiac arrest, severe chest trauma, intracardiac injections, septicemia, excessive inotropic support, and be younger than 55 years of age. In all cases, a careful clinical examination of the potential donor is undertaken to rule out coronary artery atherosclerosis and contractile dysfunction; investigations may include angiography and echocardiography. The use of coronary angiography would be dictated by patient age, sex, and risk factors. In general, a contrast left ventriculogram is avoided to reduce the risk of nephrotoxicity.

Poor ejection fraction, despite optimization of physiologic variables, would exclude a potential donation. Transplantation can proceed with mild left ventricular hypertrophy; however, wall thickness >13 mm or electrocardiogram (ECG) criteria for left ventricular hypertrophy would make transplantation unadvisable. In general, severe congenital or valvular abnormalities would preclude donation, with the exception of abnormalities in which “bench” repair can be undertaken before transplant.

Blood group ABO compatibility is important, as mismatch may result in hyperacute rejection. The donor body weight should be within 20% of that of the recipient. However, in the case of a small donor matching, using BMI or height is more accurate than using weight. Preferably, donor heart ischemic time should be less than 4 hours. Prolonged ischemic time may contribute to early allograft failure; however, techniques to allow improved tolerance of ischemia may be on the horizon.

The concept of “extended-donor criteria” is becoming popular, and outcomes are favorable. Donor hearts with one or more of the following: size mismatch, ischemic time longer than 4 hours, ventricular hypertrophy, donor age older than 55 years, malignant brain tumors, long-standing death by poisoning, and significant inotropic requirements, are at times considered for transplant. In fact, looking at a wide variety of traditional reasons not to accept a donor heart, only diabetes mellitus was found to be predictive of 1-year mortality in a recipient, leading to concerns that many viable and “less than perfect” donor hearts are not being used for transplant.

The use of non-heart-beating (donation after cardiac death) donors is now used in multiple jurisdictions for kidney, liver, and lung transplantation. There have been cases of heart transplantation from non-heart-beating donors. However, the ethical and legal issues surrounding the technique for this form of heart donation are controversial.

The goals of management are to maintain euvolemia, achieve relatively normal afterload, and optimize cardiac output (CO) without excessive use of inotropic medications, in particular β-agonists. Unfortunately, the brain-dead patient often can become extraordinarily unstable, and achieving hemodynamic stability can be a challenge. In addition, the treatment modalities to support certain end organs for donation are often at odds with each other. The onset of diabetes insipidus needs to be considered when excessive urine output (greater than 300 mL per hour) is observed and must be treated promptly with desmopressin (1-deamino-8-D-arginine vasopressin [DDAVP]). As a result of dysfunction of the hypothalamic-pituitary system, it is suggested that hormonal replacement therapy be undertaken. This includes the use of intravenous (IV) exogenous thyroid therapy, arginine vasopressin, and methylprednisolone. In addition, adequate glycemic control should be achieved.

Overall survival at 1 year is 84.8% for recipients between 50 and 64 years of age for transplants performed from April 11, 2010 to March 31, 2014. Having congenital heart disease as the indication for transplant is a powerful predictor of postoperative 1-year mortality. In addition, the requirement of extracorporeal circulatory support, dialysis, preoperative mechanical ventilation, female gender, nonidentical ABO matching, previous blood transfusions, coronary artery disease as the indication for transplant, and being hospitalized immediately before transplant all are risk factors for 1-year mortality. Mortality during the first year is greater than the next 4 years combined, so risk factors associated with 1-year mortality are also powerful predictors of 5-year mortality. For those that have survived after 1 year, allograft vasculopathy during the first posttransplant year, diabetes mellitus, treatment for rejection during the first posttransplantation year, recipient age, donor age, recipient weight, and transplant center volume are risk factors for 5-year mortality.

The most common causes of death are the following:

Within 30 days posttransplant

From 31 to 365 days posttransplant

After 5 years

The older biatrial technique involves anastomoses of the recipient and donor atrial cuffs. The bicaval technique maintains the above left atrial anastomoses and attempts to maintain cardiac anatomy with separate recipient’s bicaval anastomoses to the donor’s right atrium.
There may be an advantage of decreased need for pacemakers and improved mortality with the bicaval technique.

Congenital cardiac disease and primary pulmonary hypertension are the most common indications for combined heart/lung transplant. Other indications include cystic fibrosis, α₁-antitrypsin deficiency and other forms of lung disease, such as emphysema and idiopathic pulmonary fibrosis. The procedure is performed through a transverse thoracotomy incision, and the donor heart/lungs are transplanted en bloc. Important postoperative problems include bleeding and reperfusion lung injury, which may require inhaled NO, or occasionally extracorporeal membrane oxygenation (ECMO). Survival following heart/lung transplant is 68% and 51% at 1 and 3 years, respectively.

An ongoing worldwide shortage of donor hearts has meant ongoing pressure to manage medically patients with end-stage cardiac failure. Patients need to adhere to strict lifestyle modifications and diet; otherwise, any other therapy will have limited usefulness. As heart failure progresses, patients may respond to a variety of medications. Angiotensin-converting enzyme (ACE) inhibitors have been shown to improve symptoms and decrease mortality in patients with heart failure. Angiotensin II receptor blockers can be considered for patients intolerant of ACE inhibitors. Patients with severe forms of heart failure also may benefit from a low-dose aldosterone antagonist (spironolactone), with attention paid to potential hyperkalemia. Tailored doses of diuretic therapy may offer some symptomatic relief. β-Blockade with carvedilol, sustained-release metoprolol, or bisoprolol has been shown to reduce the risk of death. Therapy to maintain sinus rhythm is also recommended. In addition, patients with advanced heart failure may reduce their risk of sudden cardiac death by the insertion of an ICD. Furthermore, ICD implantation can be combined with cardiac resynchronization therapy (this can also be done alone), which has been shown to improve functional class and survival in advanced heart failure, in patients who are under optimal medical management. Intra-aortic balloon pump (IABP) and, increasingly, VAD implantation or semi-implantable paracorporeal devices also are finding a role in the management of patients as a bridge to transplant, particularly for those presenting in acute decompensated heart failure.

The Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) tracked 1,420 LVAD placements in 2010. Far fewer biventricular assist devices were inserted. The indications for LVAD insertion seem to be changing since 2006, when 40.8% were due to life-threatening cardiogenic shock. In 2010, only 12.3% of the patients had cardiogenic shock, and progressive decline of cardiac function (42%) presented the largest single indication. Of those that received an LVAD, 67.5% were listed or were being considered for heart transplant in 2010. In general, three major categories of patients considered for VAD include (1) temporary insertion while cardiac function recovers from insult (bridge to recovery),
(2) insertion while awaiting transplant or transplant assessment (bridge to transplant), and (3) patients who need long-term support but are not transplant candidates (destination therapy). Interestingly in 2010, the INTERMACS registry found that in 30.6% of patients, LVAD insertion was considered a destination therapy. The vast majority of VADs are continuous flow pumps instead of pulsatile flow.