**3. Treatment**

#### **3.1. Medical management**

Once heart failure is recognized, medical treatment consists of a cocktail of medications including diuretics, beta blockers, renin-angiotensin-aldosterone system blockers, mineralocorticoid receptor antagonists, digoxin, pulmonary vasodilators, calcium channel blockers, and afterload reducing agents, similar to adult-onset heart failure [1]. Treatment is tailored based on specific physiology and is outside the scope of this chapter. Other interventions include implantation of a cardioverter defibrillator [6] and cardiac resynchronization therapy [7].

## **3.2. Surgical management**

population faces is the development of heart failure, and this is currently recognized as the

In current medical practice, the gold standard for treating end stage heart failure is heart transplantation. This however remains a treatment option that is limited by donor supply. For the past several decades, the number of heart transplants that have been performed annually in the United States is between 2000 and 2500 [4]. This supply does not meet the current demands of the growing heart failure population. As the prevalence of heart failure in the ACHD population grows, the demand for heart failure treatment will continue to increase,

In addition to the concerns associated with donor supply, ACHD patients face further burdens when seeking heart transplantation as a treatment option due to their medical complexities that are not currently accounted for in the guidelines established by UNOS. These include younger age, anatomical complexities, and decreased likelihood of an implanted mechanical assist device in comparison to the non-ACHD candidates. This, in turn, leads to a lower urgency status, longer waitlist times, and a higher incidence of ACHD patients experiencing

It is evident that further evaluation of the growing ACHD population is necessary in order to provide effective management plans for the treatment of heart failure that will account for their complex circumstances. This chapter discusses current medical management, associated

The diagnosis of heart failure in ACHD is often difficult because this population may present with atypical signs and symptoms; however, diagnosis is facilitated by regular follow-up including history and physical exam, laboratory and imaging studies, and functional testing that is part of the management of these patients. Once a hemodynamic lesion is identified on imaging, correction of the lesion is usually required. If no hemodynamic lesion is present, patients are classified into two groups based on whether or not there is impaired ventricular function. Medical management of heart failure is indicated when there is impaired ventricular function without a significant hemodynamic lesion or for patients with normal ventricular function who are clinically symptomatic with either an elevated BNP or evidence of impairment of cardiopulmonary exercise testing. Regular follow-up is indicated if BNP or exercise testing is normal or for clinically, asymptomatic patients with normal ventricular function [1].

Once heart failure is recognized, medical treatment consists of a cocktail of medications including diuretics, beta blockers, renin-angiotensin-aldosterone system blockers,

treatment outcomes, and future directions in the management of ACHD patients.

placing further strain on the already overburdened transplant system.

leading cause of death for ACHD patients [3].

delisting due to clinical deterioration [5].

**2. Diagnosis**

80 Heart Transplantation

**3. Treatment**

**3.1. Medical management**

Structural intervention is often required in patients with adult CHD and ranges from catheter based therapy to heart transplantation depending on the etiology of CHD and presentation of symptoms in adulthood. The decision to undertake surgical correction must be weighed carefully against medical management as survival decreases with an increase in the number of sternotomies [8]. Additionally, the use of blood products may cause HLA sensitization, impacting the potential for later heart transplant [9]. Cardiac surgery includes pulmonary valve/conduit replacement, closure of atrial septal defects, aortic procedures, repair/revision of tetralogy of Fallot, conversion to or revision of Fontan repair, and other valvular repair/replacements [10].

Mechanical circulatory support (MCS) assistance may be indicated for patients who develop acute heart failure resistant to maximal medical management. Extracorporeal membrane oxygenation is considered for patients who develop cardiogenic shock and often serves as a "bridge to decision" therapy in this patient population [11]. Unlike standard heart failure, ECMO is particularly useful for CHD patients who develop right ventricular failure [12]. The use of ECMO should be limited to patients who have not developed multi-organ failure as prognosis is poor in this population.

The number of chronic ventricular assist device implantations continues to increase although concentrated to relatively few centers [13]. Few patients with single ventricle morphology are implanted as most patients are classified as systemic morphological left or right ventricle [13]. Similar to ECMO therapy, long-term MCS is used as a bridge to transplant or candidacy and seldom used as destination therapy [13]. Most patients are implanted with a left VAD, but there is a higher proportion of patients compared to the acquired heart failure population who require biventricular support with either biventricular VADs or a total artificial heart [13]. Across all morphologies, axial, continuous flow pumps are more commonly used; however, there is a larger proportion of pulsatile pumps used in the ACHD population compared with those with acquired heart failure [13].

Heart transplantation is considered when estimated 1-year survival is less than 80%. The decision to list for heart transplant is complex, more so than patients with acquired heart failure, and factors influencing this decision include anatomical considerations, presence of non-heart end-stage organ failure, progressive cyanosis, degree of pulmonary hypertension, and cardiopulmonary exercise testing [14]. Patients with single ventricle morphology present particular anatomical and vascular challenges, as they often require additional surgical procedures at the time of transplant including pulmonary artery and abnormal systemic venous return reconstruction. Overall, patient selection is crucial for the success of heart transplant in adults with congenital heart disease.
