Think Outside the Heart: Noncardiac Complications and Considerations in the Adult Congenital Patient

Tackling the big issues facing the adult congenital heart disease (ACHD) population continues to gain traction in a field that has now come of age. In the past two years, we have seen AHA scientific statements on topics ranging from heart failure and mechanical support to the management of pregnancy in complex congenital heart disease.^1-3 We also have the implementation of new training guidelines, an American Board of Internal Medicine (ABIM) board examination (co-sponsored by the American Board of Pediatrics), and ACHD care center accreditation through the Adult Congenital Heart Association (ACHA).

Still, some of the most complex issues responsible for significant morbidity and mortality in the ACHD patient lie outside of the heart. Lui and colleagues diligently undertake this endeavor with a comprehensive review of noncardiac complications in ACHD patients.⁴ For the experienced ACHD practitioner, each section conjures up thoughts of patients that have had such complications and leaves one with greater comprehension and strategies to address these issues. For the trainee in adult or pediatric cardiology or for those not specifically trained or specialized in ACHD, the document serves as a road map to understanding, diagnosing and treating the noncardiac challenges for ACHD patients.

The very fact that we are now facing these long-term extra-cardiac challenges in ACHD is a testament to the profound improvements in surgery, imaging, medical therapy and catheter based interventions that have expanded the population of congenital heart disease (CHD) patients and resulted in adult survival estimates of greater than 90%.⁵ The most recent statistics estimate 1 in 150 adults have some form of CHD. The number of adults with CHD has surpassed the number of children – estimated at 1,400,000 adults compared to 1,000,000 children in 2010 in the United States.⁶ Nearly one-third of these patients have severe forms of CHD. Thus, we have a generation of patients who are at risk of developing chronic multisystem disease in adulthood secondary to their hemodynamic derangements as well as the normal processes of aging.

ACHD patients frequently interface with the medical system for their noncardiac illnesses well after they have attained significant morbidity. Routine surveillance is only gaining widespread acceptance particularly for screening of renal, pulmonary and hepatic disease.⁷ This in the face of almost 50% of young adults with impaired renal function highlighting the intricate connection of the cardiorenal system.⁸ Furthermore, early detection of liver disease in this population of patients who suffer from hemodynamic stresses (venous congestion, ischemic injury) and non-hemodynamic factors such as hepatitis C infection are paramount. Particularly concerning is the recognition of increasing numbers of patients with oncologic diagnoses.⁹ Patients with CHD have risk factors that start with in-utero hemodynamic derangements which then compound and evolve from various surgical palliations and associated cardiac bypass exposures.

Additionally, many a patient have been psychosocially disabled by one’s relationship with his/her own chronic disease that may result in a life of inactivity, poor dietary habits and limited emotional well-being.¹⁰ While these issues and the resultant obesity, hypertension, lipid disorders and insulin resistance – to name a few – are pervasive in our society, they are magnified in the ACHD population. A prime example is the large number of patients with unrecognized and untreated sleep apnea – a condition worsened by the prevalence of restrictive and obstructive lung disease secondary to scarring from open chest operations.¹¹ The presence of sleep apnea can have a profound impact on oxygenation and ventilation, development of arrhythmias, and detrimentally affect the hemodynamics of various palliations, most notably patients with a cavopulmonary or Fontan connection.

For many ACHD patients, the most hazardous endeavor is undergoing elective non-cardiac surgery in a setting that is ill equipped to deal with their comorbidities. Many patients will under report their functional limitations, therefore, providers may mistakenly perceive that younger and seemingly well-functioning patients as having near normal cardiopulmonary reserve. Not surprisingly, up to 40% of adverse events in ACHD patients undergoing noncardiac surgery result from inadequate risk assessment in this setting.¹²

Lui et al. provide caution and guidance for these and many common challenges in ACHD patients and urge an interdisciplinary approach to thinking outside the heart. The safety, longevity, productivity and well-being of our patients depend on it.