Heart Transplantation Topic Review

Clinically, the current practice of orthotopic cardiac transplantation involves the surgical removal of a patient’s terminally diseased heart and surgical implantation of a healthy donor heart.

Heart transplantation is considered a therapeutic option only in end-stage heart failure (HF), also known as American College of Cardiology/American Heart Association (ACC/AHA) Stage D HF, refractory to other therapies. Patients with NYHA Class III to IV HF should be referred to an HF program experienced in cardiac transplantation, especially if the VO₂ max is below 14 mL/kg on cardiopulmonary stress testing.[Heidenreich PA, et al. J Am Coll Cardiol. 2022;e340-e341]

The 2022 ACC/AHA Guideline for the Management of Heart Failure recommends (Class of Recommendation 1) cardiac transplant in selected patients with advanced HF despite guideline-directed medical therapy, to improve survival and quality of life.[Heidenreich PA, et al. J Am Coll Cardiol. 2022;e340] Caretaker status and goals of care should be taken into consideration during patient selection,[Heidenreich PA, et al. J Am Coll Cardiol. 2022;e341] as should the patient’s age, weight, renal function, diabetes, cerebral and peripheral vascular disease, frailty and psychosocial aspects; all of these factors may be a contraindication for transplantation.[Mehra MR, et al. J Heart Lung Transpl. 2016;3-4]

Heart transplantation improves survival in carefully selected individuals. Median postoperative survival is now more than 12 years, compared to less than 2 years for Stage D HF without advanced treatment. Survival at 1, 3 and 5 years is 90.3%, 84.7% and 79.6%, respectively. [Heidenreich PA, et al. J Am Coll Cardiol. 2022;e341]

Perioperative mortality is approximately 5%. Postoperative management includes lifelong immunosuppression with a multidrug approach including corticosteroids, calcineurin inhibitors and anti-lymphocyte drugs such as mycophenolate to manage graft rejection.  

Heart transplantation is not appropriate for patients with severe fixed pulmonary hypertension, malignancy, a significant illness with limited survival or any illness that would have a high likelihood of occurring in the transplanted heart. Patients older than 70 years may still be considered; however, most institutions use this age as a relative contraindication.

To minimize waitlist mortality and maximize posttransplant outcomes, the United Network for Organ Sharing (UNOS) and Organ Procurement and Transplantation Network (OPTN) in the United States revised their heart allocation policy in 2018. The new system includes six categories for adult heart allocation, shown in the Figure.[Shore S, et al. Circ Cardiovasc Qual Outcomes. 2020;3c]

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Status 1

• Extracorporeal membrane oxygenation (up to 7 days)
• Nondischargeable surgically implanted ventricular assist device (VAD)
• Mechanical circulatory support device (MCSD) with life-threatening ventricular arrhythmia

Status 2

• Intra-aortic balloon pump (up to 14 days)
• Sustained ventricular tachycardia/ventricular fibrillation
• Nondischargeable, surgically implanted, nonendovascular left VAD (up to 14 days)
• MCSD with device malfunction/mechanical failure
• Total artificial heart
• Dischargeable biventricular assist device
• Acute endovascular percutaneous circulatory support (up to 14 days)

Status 3

• Dischargeable left VAD (up to 30 days)
• Multiple inotropes or single high-dose inotropes with continuous hemodynamic monitoring
• MCSD with device infection, hemolysis, pump thrombosis, right heart failure, mucosal bleeding and aortic insufficiency
• Extracorporeal membrane oxygenation after 7 days or any other temporary MCSD after 14 days

Status 4

• Stable left VAD candidates not using 30-day discretionary period
• Inotropes without hemodynamic monitoring
• Congenital heart disease
• Ischemic heart disease with intractable angina
• Hypertrophic cardiomyopathy
• Restrictive cardiomyopathy
• Amyloidosis
• Re-transplant

Status 5

• Combined organ transplants

Status 6

• All other active candidates

References:

• Heidenreich PA, et al. J Am Coll Cardiol. 2022;doi:10.1016/j.jacc.2021.12.012.
• Mehra MR, et al. J Heart Lung Transplant. 2016;doi:10.1016/j.healun.2015.10.023.
• Shore S, et al. Circ Cardiovasc Qual Outcomes. 2020;doi:10.1161/CIRCOUTCOMES.119.005795.