A 14-year-old Girl with Hypoplastic Left Heart Syndrome Comes for a Well-child Visit
After reading this article and answering the review questions, the reader will be able to:
- Explain single ventricle physiology and associated increased risk for neurocognitive disabilities
- Discuss the unique health care needs of the patient with complex congenital heart disease (CHD)
- Reinforce the need for transition to the adult health care system as adolescents with CHD grow older.
A 14-year-old girl comes to your clinic for a routine well-child check. She is new to your practice, having just moved with her parents from out of state. Review of her records shows that she has Hypoplastic Left Heart Syndrome (HLHS) and underwent a series of three open-heart surgeries when she was younger. Her most recent surgery was an extracardiac fenestrated Fontan procedure performed at three years of age. Her mother reports that she is doing quite well overall, although she has noticed her daughter has more difficulty in school now that she is in 8th grade. When questioned, the girl admits that she daydreams and has trouble paying attention to her teachers.
Further review of her records shows that she is behind in her vaccinations. Her only medication is aspirin, 81mg once daily. On review of systems, she denies any cyanosis, pallor, palpitations, syncope or presyncope, chest pain, respiratory distress, or edema. She has been menarchal for about six months and has regular menstrual cycles. Her last evaluation by a pediatric cardiologist was three years ago, and she had an echocardiogram at that visit that showed good right ventricular function, mild tricuspid regurgitation, and an unobstructed neoaorta.
On physical exam, she is well appearing with normal vital signs. Her pulse oximetry on her right finger is 92%. She has a well-healed sternotomy scar. On cardiac exam, she has a normal S1 and a single S2. She has no murmurs. Her liver is palpable at the right costal margin. She has two-plus radial and femoral pulses bilaterally. Her extremities are warm and she has some subtle clubbing of her fingers.
Overview of CHD and Single Ventricle Physiology
CHD, as a group, is the most common major congenital anomaly, with a population frequency of about 1%1. Until recently, severe CHD was frequently fatal in early life. However, with improved medical care and surgical techniques, the vast majority of infants born with CHD now survive, many into adulthood2-6. One example of this type of complex CHD is Hypoplastic Left Heart Syndrome (HLHS). These infants are born with severe hypoplasia of the mitral valve, aortic valve, and aortic arch (Figure 1: HLHS). These infants survive to term due to the presence of a patent ductus arteriosus (PDA), thus HLHS is a ductal dependent lesion. Untreated, HLHS is universally fatal in the first few weeks of life due to closure of the PDA.
The most common treatment strategy employed in children with HLHS is single ventricle palliation, consisting of a series of three surgeries. The first surgery, the Norwood procedure, is performed in the first few days of life (Figure 2: Norwood). The tiny native aorta is attached to the pulmonary artery to create a "neoaorta", which allows the right ventricle to pump blood to the body. A Blalock-Taussig shunt allows blood to flow from the innominate artery into the pulmonary arteries. This allows the single right ventricle to "pump" blood to both the systemic and pulmonary circulations.
The second and third surgeries together create the Fontan physiology, which is the strategy used for most patients who have any form of single ventricle disease (i.e., HLHS, tricuspid atresia, unbalanced atrioventricular canal, and others). A Fontan circuit allows systemic venous blood to flow directly from the systemic veins into the pulmonary arteries, bypassing the heart. This reserves the single ventricle as the pump to the systemic circulation, which allows for near-complete separation of the systemic and pulmonary circulations.
The second surgery, most commonly the bidirectional Glenn operation, is typically performed between four and six months of age. The superior vena cava is disconnected from the right atrium and connected to the right pulmonary artery (the Blalock-Taussig shunt is taken down). Blood from the inferior vena cava still returns to the right atrium and is pumped out to the body through the right ventricle, so the patient is still cyanotic (pulse oximetry 80-85% is typical).
The third stage of surgery is the Fontan operation, which is typically performed between 2 and 4 years of age (Figure 3: Fontan). In the Fontan operation, the inferior vena cava is disconnected from the right atrium and an artificial tube is used to baffle the flow up to the pulmonary arteries. Typically a fenestration, or a small hole, is created between the Fontan baffle and the right atrium to allow "pop-off" of blood from the inferior vena cava into the right atrium, creating a right-to-left shunt. Now, all the blood returning from the body (except for the fenestration and the coronary sinus) passively flows into the lungs, providing separation of the systemic and pulmonary circulations. Due to the deoxygenated blood that crosses the fenestration and the venous blood exiting the coronary sinus into the right atrium, the oxygen saturation of a Fontan patient is not 100%; typically greater than 90% is acceptable.
Special Health Care Considerations for Children with Complex CHD
The Fontan procedure is the last planned surgical procedure in any patient with single ventricle physiology. These patients, like all patients with complex CHD, require lifelong care from both primary care providers and subspecialists - they have been repaired, not cured7.
Many patients and their families struggle with medical compliance, particularly when multiple care providers are involved. Children with CHD are no exception. Many pediatric patients will continue to see their primary care provider but will have difficulty keeping regular appointments with subspecialists8, particularly when travel is involved. Removing obstacles to compliance is essential for their long-term health.
Children with complex CHD, like many children with chronic illness and prolonged hospitalizations, often fall behind on their vaccinations. Unless a child has received a heart transplant, there is no cardiac contraindication to any vaccination, including live-virus vaccines. Children with CHD in particular should receive annual influenza vaccination after 6 months of age, as they represent a vulnerable population. Children aged 2 to 6 years who have cyanotic CHD or who receive medication for congestive heart failure should receive the 23-valent pneumococcal polysaccharide vaccine, as well12.
Prophylaxis against respiratory syncytial virus (RSV) is of critical importance in CHD patients 24 months of age or less who qualify. Cardiac indications for RSV prophylaxis are shown in Table 1.
Children and adolescents with any form of complex CHD (not just single ventricle physiology) are at increased risk for both learning disabilities and attention deficit-hyperactivity disorder (ADHD). Full-scale IQ testing of children with complex CHD show that they have IQs within the normal range, although as a population they are below the mean. When specific neurocognitive testing is done, children with CHD are more likely to have lower scores in attention, executive function, memory, language, comprehending instructions, and sensorimotor function9. In a recent study, almost 50% of school-aged children with complex CHD required special school services at least part-time.10
When assessed by parents and teachers for ADHD-related symptoms, children with CHD are two to three times more likely than healthy children to exhibit inattention, hyperactivity, or both10. Children with CHD typically tolerate traditional ADHD medications quite well, although providers are encouraged to consult their patient's pediatric cardiologist before initiating treatment for ADHD.
Many children with complex CHD (although certainly not all) require some form of anticoagulation. Patients with single ventricle physiology are virtually always anticoagulated, although the exact practices vary from one pediatric cardiologist to another. Warfarin or aspirin are most commonly used, particularly when a fenestration is present. This is due to the risk of a paradoxical embolism, which could cross the fenestration into the right atrium, into the right ventricle, and out the aorta.
Not all patients with CHD require prophylaxis for endocarditis, but some groups of patients still do. Fontan patients should receive prophylaxis before dental procedures, according to the 2007 American Heart Association guidelines11. Table 2 lists the conditions for which endocarditis prophylaxis is indicated before dental procedures.
Patients with CHD are often at increased risk for early atherosclerotic disease, and so current American Academy of Pediatrics guidelines recommend screening these patients with fasting lipid profiles after two years of age. If their lipid levels are normal, screening can be repeated every five years13. If levels are abnormal, dietary and lifestyle modification is indicated, and referral to the appropriate subspecialist may be needed.
Contraception and Pregnancy
Sexual health and family planning are important issues for adolescents with CHD, just as for all adolescents. Adolescents with CHD represent a heterogenous group. Some forms of CHD do not place women at any increased risk during pregnancy, whereas other defects are associated with up to 50% mortality. The World Health Organization classifies patients with Fontan circulation and good heart function as class III pregnancy risk, with a significantly increased risk of mortality or severe morbidity14. If pregnancy is decided upon, these patients require intensive monitoring by specialists throughout pregnancy and the peripartum period.
These risks of pregnancy make counseling and effective contraception for these patients of critical importance. While combination oral contraceptive pills may seem an obvious choice, the estrogen component is associated with increased risk of thromboembolism, and is therefore contraindicated in patients with Fontan circulation15.
Progesterone-only birth control, usually in the form of Implanon®, is often recommended. Depo-Provera® injections can cause hematomas in anticoagulated patients, intrauterine device implantation carries risk, and progesterone-only pills (the "minipill") may lack appropriate efficacy14. Cerazette®, a newer progesterone-only pill, has higher efficacy than traditional minipills, but is not FDA-approved in the United States. Ultimately, it is important to consult a practitioner with experience in this area.
Emergency contraception (Plan B®) is considered safe in patients with all forms of CHD14. As with any medical treatment, known risks of each of these contraceptive methods must be weighed against benefits. Adolescents also need to be reminded that none of these contraceptive methods protect against sexually transmitted diseases.
All adolescents with complex medical histories require education about their disease and medical history. Adolescents with complex CHD will require an organized transition to appropriately prepared adult care providers. Many of these patients can have full adult lives, including families and successful careers, with few limitations. These patients as a group, however, have more problems obtaining higher education, job training, and health insurance than their healthy counterparts7.
CHD is Common
Today, there are approximately one million adults and 800,000 children living with CHD in the United States. Due to increased survival, the number of adults with CHD is projected to increase by 5% per year. Half of these adults have complex CHD and are at high risk of developing new heart problems as they age1. The US health care system has a severe shortage of practitioners and facilities equipped to care for these patients16. Advocacy and increased awareness are needed - our patients are waiting for it.
- Park, Myung K. The Pediatric Cardiology Handbook: Mobile Medicine Series, 4th ed. Mosby, 2009.
- Park, Myung K. Pediatric Cardiology for Practitioners, 5th ed. Mosby, 2007.
- Wilson W, Taubert KA, Gewitz M, et al. Prevention of infectious endocarditis: guidelines from the American Heart Association. Circulation 2007;116:1736-1754.
- Marelli AJ, Mackie AS, Ionescu-Ittu R, et al. Congenital heart disease in the general population: changing prevalence and age distribution. Circulation 2007;115:163-72.
- Perloff JK, Warnes CA. Challenges posed by adults with repaired congenital heart disease. Circulation 2001;103:2637-43.
- Khairy P, Poirer N, Mercier LA. Univentricular heart. Circulation 2007;115:800-12.
- Khairy P, Fernandes SM, Mayer JE Jr., et al. Long-term survival, modes of death, and predictors of mortality in patients with Fontan surgery. Circulation 2008;117:85-92.
- Congenital heart disease after childhood: an expanding patient population. 22nd Bethesda Conference, Maryland, October 18-19, 1990. J Am Coll Cardiol 1991;18:311-42.
- Gatzoulis MA, Webb GD. Adults with congenital heart disease: a growing population. In: Gatzulis MA, Webb GD, Daubeney PEF, editors. Diagnosis and Management of Adult Congenital Heart Disease. London: Churchill Livingston, 2003:3-6.
- Knauth A, Verstappen A, Reiss J, et al. Transition and transfer from pediatric to adult care of the young adult with complex congenital heart disease. Cardiol Clin 2006;24:619-629.
- Mackie AS, Ionescu-Ittu R, Therrien J, et al. Children and adults with congenital heart disease lost to follow-up: who and when? Circulation 2009;120;302-309.
- Miatton M, De Wolf D, Francois K, et al. Neuropsychological performance in school-aged children with surgically corrected congenital heart disease. J Pediatr 2007;151:73-8).
- Shillingford AJ, Glanzman MM, Ittenbach RF, et al. Inattention, hyperactivity, and school performance in a population of school-age children with complex congenital heart disease. Pediatrics 2008;121;e759-767.
- Wilson W, Taubert KA, Gewitz M, et al. Prevention of infectious endocarditis: guidelines from the American Heart Association. Circulation 2007;116:1736-1754.
- American Academy of Pediatrics Committee on Infectious Diseases. Policy statement: recommendations for the prevention of pneumococcal infections, including the use of pneumococcal conjugate vaccine (Prevnar), pneumococcal polysaccharide vaccine, and antibiotic prophylaxis. Pediatrics. 2000;106(2 Pt 1):362-6.
- Kavey RW, Allada V, Daniels SR, et al. Cardiovascular risk reduction in high-risk patients: a scientific statement from the American Heart Association expert panel on population and prevention science; the councils on cardiovascular disease in the young, epidemiology and prevention, nutrition, physical activity, and metabolism, high blood pressure research, cardiovascular nursing, and the kidney in heart disease; and the interdisciplinary working group on quality of care and outcomes research. Circulation 2006;114:2710-2738.
- Thorne S, Nelson-Piercy C, MacGregor A, et al. Pregnancy and contraception in heart disease and pulmonary arterial hypertension. J Fam Plann Reprod Health Care 2006; 32(2)00-00.
- World Health Organization (WHO), Department of Reproductive Health. Medical eligibility criteria for contraceptive use (4th ed.). Geneva, Switzerland: WHO, 2010.
- Child JS, Collins-Nakai RL, Alpert JS, et al. Task force 3: workforce description and educational requirements for the care of adults with congenital heart disease. 32nd Bethesda Conference, Bethesda, Maryland. J Am Coll Cardiol 2001;37:1183-87.
Children who SHOULD receive RSV prophylaxis
Children who generally SHOULD NOT receive RSV prophylaxis
Children with hemodynamically significant acyanotic CHD who require medication to control congestive heart failure
Children with hemodynamically insignificant CHD (eg, small secundum ASD, small VSD, pulmonic stenosis, uncomplicated aortic stenosis, mild coarctation of the aorta, or small PDA)
Children with moderate to severe pulmonary hypertension
Children with heart defects already surgically corrected, unless they continue to require medication for congestive heart failure
Children with cyanotic CHD
Children with mild cardiomyopathy that do not receive medical therapy for the condition.
Adapted from Red Book, 2009. The American Academy of Pediatrics.
Prosthetic cardiac valve
Cardiac valve repaired with prosthetic material
Prior history of endocarditis
Unrepaired cyanotic CHD
Cyanotic CHD repaired with palliative shunts and conduits
Any CHD repaired (surgically or catheter-based) with prosthetic material in the last 6 months
Any CHD repaired with prosthetic material with residual defects at the site of the patch or device
Cardiac transplant patients with valvulopathy
Adapted from the American Heart Association guidelines for prevention of infective endocarditis, published in Circulation 2007;116;1736-1754.
Arrows indicate the direction of blood flow in the heart of a neonate with HLHS. Blue arrows indicate deoxygenated blood, red arrows indicate fully oxygenated blood, and purple arrows indicate mixing. Note that all the blood flow to the body is through the patent ductus arteriosus.
Arrows indicate the direction of blood flow in the heart of a neonate with HLHS who has undergone a Norwood procedure. Note the presence of the Blalock-Taussig shunt, the creation of the neoaorta, and the removal of the atrial septum.
Again, arrows indicate the direction of blood flow in a child who has undergone the Glenn and Fontan procedures, allowing for near-complete separation of the pulmonary and systemic circulations. The fenestration allows some deoxygenated blood to cross into the systemic circulation.