Adult Congenital Cardiac Surgery

Epidemiology

There are more adults than children living with congenital heart disease, and the population continues to grow. The prevalence of adults with congenital heart disease in Quebec, Canada, was 6.12 per 1000 for the year 2010, which was a 57% increase compared with 2000. This compares with an only 10% increase in the prevalence of children with congenital heart disease during the same time period. This presents several unique challenges to the health care providers that care for these patients.

In 2001, the 32nd Bethesda Conference developed guidelines for resource allocation and program development directed at adults with congenital heart disease. The model for delivery of care focuses on classification of congenital heart defects into different levels of anatomic complexity ( Box 131-1 ), with referral to specialized adult congenital disease centers for increasing levels of such classification. More than half of the ACHD population is believed to be at increased risk for sudden cardiac death, need for reoperation, and other severe complications. This report estimated that 15% of the ACHD population have anatomically complex disease and require regular follow-up at a specialized center for adult congenital heart disease, and an additional 38% have moderate anatomic complexity of disease requiring periodic follow-up in a specialized center. The British Cardiac Society Working Party published a similar document addressing the care for the GUCH (grown-up congenital heart) population. The consensus of both documents is that all patients (with the exception of those with simple heart lesions) should receive lifelong specialized ACHD care.

Structured ACHD Programs

Over the past decade, there has been an increase in the number of centers with specialized multidisciplinary teams committed to the lifelong care of ACHD patients. Many challenges are involved in creating and maintaining a successful team of specialized ACHD providers. Health care providers who specialize in the care of these patients have various levels of experience in ACHD diagnosis and management. Although they are committed to the care of their patients, they may not have had the benefit of training in this subspecialty. Programs that specialize in ACHD care excel in multidisciplinary collaboration with specialists in not only congenital cardiac disease but also reproductive and obstetric care, nephrology, hepatology, hematology, pulmonary, rheumatology, psychiatric support, palliative care, and transition education. From a cardiac perspective, it is essential to have experienced clinicians with expertise in imaging, electrophysiology, interventional catheterization, congenital cardiac surgery, cardiac anesthesia, critical care, advanced heart failure management, and transplant medicine. The organizational structure should be regionally coordinated, so that regional centers caring for adults with congenital heart disease can easily consult and refer to the specialized programs.

Lapse in medical care in adults with congenital heart disease results in adverse outcomes. In a study of 158 adult patients referred to one ACHD center, lapse of medical care, defined as an interval of more than 2 years, occurred for 99 patients (63%). The median duration of lapse of care was 10 years. Patients with lapse of care were 3.1 times more likely to require urgent cardiac interventions ( P = 0.003). In a multicenter study of 922 patients at 12 ACHD centers, 42% experienced a gap in cardiology care that lasted longer than 3 years, and 8% had a gap longer than a decade. The mean age at the first gap was 19.9 years. The most common reasons for gaps included feeling well, being unaware that follow-up was required, and complete absence from medical care. Disease complexity was predictive of a gap in care among 59% of mild, 42% of moderate, and 26% of severe disease patients reporting gaps ( P < 0.0001).

Emergencies in the ACHD patient are of particular concern. In one multicenter study of hospital admissions of adults with congenital heart disease, 63% of emergent admissions required cooperation with another specialized department. An additional challenge that faces the ACHD population is lack of insurance coverage. Congenital heart disease patients without private insurance and older than 17 years are at higher risk of being admitted via the emergency room.

A critical volume of patients is needed to maintain expertise in the various disciplines required in the care of ACHD patients. Adult congenital heart surgery should be performed only by surgeons who are experienced in all aspects of congenital heart surgery. In an analysis of the Nationwide Inpatient Sample, early mortality and length of stay were lower for patients who underwent ACHD procedures performed by surgeons with expertise in congenital heart disease. The choice of location for surgery should depend on not only the surgeon but also the multidisciplinary team's support for management of adult comorbidities. The optimal surgical location may be center dependent. Certain factors place adults with congenital heart disease at higher risk of death when surgery is performed at freestanding pediatric hospitals. These risk factors include older age, male sex, government-sponsored insurance, and greater surgical complexity. Additionally, greater surgical complexity, government-sponsored insurance, DiGeorge syndrome, weekend admissions, and depression result in higher resource use in ACHD surgical admissions. Analysis of the Nationwide Inpatient Sample examining ACHD surgical admissions to adult hospitals identified nonelective admissions, government-sponsored insurance, surgical complexity, heart failure, renal failure, and complications as risk factors for higher resource utilization.

Surgical Indications in ACHD Patients

The ACC and American Heart Association (AHA) have developed guidelines for management of adults with congenital heart disease, which include recommendations for surgical interventions. It is important to recognize the decision to proceed with surgery in the ACHD patient is multifactorial. The goals of prolonging survival and improving quality of life are paramount. The use of previously established measures of physical functioning (such as New York Heart Association [NYHA] class) is difficult to assess in the ACHD patient. Many patients, having lived with the sequelae of cardiac disease since birth, do not perceive themselves as “limited” in the setting of markedly diminished objective exercise capacity. There is a common misconception that surgical palliation of a congenital heart defect in infancy or childhood is “curative.” Therefore, by the time that patients are formally evaluated, ventricular dysfunction may be severe and irreversible. Despite this, NYHA class of III or higher has been associated with increased operative mortality, major adverse events, and greater length of stay in ACHD patients undergoing surgery.

Pediatric surgical risk scoring systems, such as Aristotle or STAT, may offer some prognostic value in ACHD patients but have limitations in their applicability. For example, high-risk surgeries often include procedures primarily done in infants (such as the Norwood operation or interrupted aortic arch repair), and the distribution of procedures in ACHD patients is skewed toward those classified as lower risk. Furthermore, patient comorbidities that may influence surgical outcome in the pediatric population (such as those in the Aristotle Comprehensive Scoring system, including low birth weight, prematurity, and noncardiac congenital anomalies) may not be as applicable in the adult population, whereas diabetes, hypertension, vascular disease, markers of hepatic disease, and NYHA class may be more meaningful. In a multicenter study of 2012 ACHD patients requiring surgery from 13 European countries, preoperative cyanosis, arrhythmias, and NYHA class of III or higher were risk factors for hospital mortality.

A subset of ACHD patients are referred for primary surgical correction. The principle reason for this is late diagnosis, for example, patients with atrial septal defects or aortic coarctation. Patients may also be referred as adults for a condition that was previously considered inoperable, or because they are from a geographic region without local surgical congenital heart expertise, or because they have anatomically complex lesions but balanced systemic and pulmonary blood flows. Patients with unrepaired tetralogy of Fallot and pulmonary atresia have a poor prognosis; survival beyond the fifth decade is rare.