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A heart transplant is performed in patients with refractory acute and chronic heart failure. An orthotopic heart transplant is the most commonly utilized technique though a heterotropic transplant has also been described and performed. Main indications for transplant in chronic heart failure include patients who have disabling symptoms despite optimal medical management or refractory arrhythmias despite medical and electrophysiological procedures. For acute heart failure refractory to inotropes and mechanical circulatory devices, a heart transplant is indicated. This activity reviews the indications, contraindications, techniques, and common complications of the heart transplant procedure and highlights the role of the interprofessional team in performing this procedure and post-transplant surveillance. Objectives: Identify the indications and contraindications for heart transplants. Outline the selection process of the patient considered appropriate candidates for cardiac transplantation. Summarize the common post-transplant complications including early and delayed complications. Describe interprofessional team strategies for improving care coordination and communication to advance the heart transplantation procedure and improve patient outcomes. Access free multiple choice questions on this topic.

Patients with advanced heart failure requiring mechanical circulatory support and inotropic support have a poor prognosis.[1] Cardiac transplantation in a selected cohort of such patients can be the treatment of choice. The early experience with heart transplants was disappointing. In 1967, the first patient to receive a heart transplant died of an overwhelming infection after 17 days.[2] However, with the advent of immunosuppressive therapies and a better understanding of human anatomy and surgical techniques, cardiac transplantation started gaining popularity in the 1990s. The International Society for Heart and Lung Transplantation (ISHLT) reported maximum transplants during the period of 1993-2004; however, in recent years, the numbers reported have grown even further.[3] With well-defined indications now set forth by the American College of Cardiology/American Heart Association/Heart Failure Society of America (ACC/AHA/HFSA) and European Society of Cardiology (ESC) in collaboration with ISHLT, more people are on the waiting list than is the availability of the organ itself.[4] This review will focus on the updated guidelines on indications and contraindications of a heart transplant, commonly utilized techniques, post-transplant immunosuppression, and common complications of the procedure.

Post-transplant complications are broadly divided into early and late complications.[15][16] Early Complications They occur in the immediate postoperative period within days of transplantation. Primary Graft Dysfunction (PGD) Primary graft dysfunction (PGD) is defined as the failure of graft function within the first 24 hours after transplantation in the absence of hyperacute rejection, pulmonary hypertension, or known surgical complications such as bleeding or tamponade. The International Society of Heart and Lung Transplant (ISHLT) reported the PGD incidence to be 33% in all cardiac transplant procedures. In some case series, patients with severe PGD, have shown to have a survival of 44% at one year.[17] Rejection Rejection occurs as a result of interaction between the recipient's immune system and the allograft. It may be categorized by the type of immune response (cell-mediated vs. antibody-mediated) and by severity (ranging from mild rejection without allograft dysfunction to severe rejection with hemodynamic compromise). The incidence of rejection requiring augmentation of immunosuppression has fallen from 23.5% (2004–2006) with contemporary rates approximately 13% (2010–2014) between discharge from hospital and one year. Surveillance endomyocardial biopsies (generally 10 to 12 in the first year) are performed to look for evidence of rejection. Grading is standardized according to the 2005 revised ISHLT nomenclature, which includes the use of immunohistochemistry. Infection The use of immunosuppression inevitably increases the risk of infection. The risk of death due to infection is greatest in the first year post-transplant when maximum immunosuppression is being used. Patients should be vaccinated for influenza and pneumococcal infections. Live vaccines are contraindicated. Routine prophylaxis for pneumocystis jerovecii, cytomegalovirus, candida, and in some cases, herpes is given to these patients. Delayed Complications They occur late in the transplantation period after months or years of transplant. Cardiac Allograft Vasculopathy

The use of immunosuppression inevitably increases the risk of infection. The risk of death due to infection is greatest in the first year post-transplant when maximum immunosuppression is being used. Patients should be vaccinated for influenza and pneumococcal infections. Live vaccines are contraindicated. Routine prophylaxis for pneumocystis jerovecii, cytomegalovirus, candida, and in some cases, herpes is given to these patients. Delayed Complications They occur late in the transplantation period after months or years of transplant. Cardiac Allograft Vasculopathy Cardiac allograft vasculopathy (CAV) is a process that leads to the narrowing or occlusion of the coronary arteries of the allograft. CAV is a significant cause of death late post-transplant, and its incidence increases with the time elapsed since transplant. It is a combined immunological and non-immunological insult. Intimal hyperproliferation due to smooth muscle cell hyperplasia and accumulation of lipids and inflammatory cells is the hallmark of the pathology of a biopsy specimen. Both epicardial and endocardial vessels are involved. Most patients may not have any symptoms and may be detected on routine biopsy surveillance. Some patients may have angina or heart failure symptoms at presentation. Due to the diffuse nature of the disease, outcomes of revascularization are not good. Post-transplant use of statins and rapamycin, when given early in the post-transplant period, may delay the development of CAV. Common risk factors for developing CAV can include immune-mediated (mismatch between donor and recipient including HLA and DR) and non-immune mediated (increased age, recipient coronary artery disease, or risk factors like smoking, hypertension, hyperlipidemia, and obesity). This vasculopathy can present as heart failure and needs to be monitored using regular echocardiographic examinations and hemodynamic measurements.[18][19] Malignancy New onset of solid malignancies occurs in around 10% of transplant patients after 1 to 5 years of transplant. Immunosuppression Related Side Effects

Cardiac allograft vasculopathy (CAV) is a process that leads to the narrowing or occlusion of the coronary arteries of the allograft. CAV is a significant cause of death late post-transplant, and its incidence increases with the time elapsed since transplant. It is a combined immunological and non-immunological insult. Intimal hyperproliferation due to smooth muscle cell hyperplasia and accumulation of lipids and inflammatory cells is the hallmark of the pathology of a biopsy specimen. Both epicardial and endocardial vessels are involved. Most patients may not have any symptoms and may be detected on routine biopsy surveillance. Some patients may have angina or heart failure symptoms at presentation. Due to the diffuse nature of the disease, outcomes of revascularization are not good. Post-transplant use of statins and rapamycin, when given early in the post-transplant period, may delay the development of CAV. Common risk factors for developing CAV can include immune-mediated (mismatch between donor and recipient including HLA and DR) and non-immune mediated (increased age, recipient coronary artery disease, or risk factors like smoking, hypertension, hyperlipidemia, and obesity). This vasculopathy can present as heart failure and needs to be monitored using regular echocardiographic examinations and hemodynamic measurements.[18][19] Malignancy New onset of solid malignancies occurs in around 10% of transplant patients after 1 to 5 years of transplant. Immunosuppression Related Side Effects Human papillomavirus (HPV) related squamous cell cancer is the most common malignancy reported. Avoiding sun exposure is recommended in these patients. Ebstein-Barr virus-related post-transplantation lymphoproliferative (PTLD) is also common in these patients from immunosuppression. Other toxicities related to tacrolimus or sirolimus use include renal disease, diabetes, hyperlipidemia, and metabolic derangements (hypoglycemia and hyperglycemia).[20]

The management of advanced heart failure, whether acute or chronic, is challenging and complex. With improved surgical and organ preservation strategies, a heart transplant is an option for eligible patients. To derive good outcomes, the goals and objectives of the heart transplantation have to be defined prior to taking the patient to surgery. In some cases, chronic infections, cirrhosis, and chronic kidney diseases, as well as psychosocial factors, may preclude cardiac transplants. Proper screening is thus required for proper patient selection. As with any other complex procedure, the preoperative workup must be thorough, and the patient should be seen by a pulmonologist and cardiologist to optimize lung and cardiac function. Due to the potential of complications from immunosuppression and the procedure itself, routine surveillance and biopsies are recommended.[22] To improve outcomes, the ISHLT working in collaboration with ACC/AHA/HFSA and ESC has issued indications for a heart transplant in both acute and chronic heart failure patients. For optimum results, patients with any contraindications to heart transplants should be excluded from the list and managed medically and on mechanical support. In addition to complications of the surgery, both early and late complications can complicate heart transplants. Hence careful supervision is needed in the immediate post-operative period as well as years after transplant. An integrated interprofessional team with a cardiologist, cardiothoracic surgeon, trained nursing staff, and pharmacist well trained with titration and side effects of immunosuppressants can greatly improve heart transplantation outcomes. The role of a primary care physician in follow-up is also crucial; thus, further emphasizing the need for an interprofessional approach to the management of heart transplant patients. The need for meticulous planning and discussion with other professionals involved in the management of the patient is highly recommended to lower the morbidity and improve post-transplant outcomes.[23][24]