Chapter 500. Health Care Management for the Child with Cardiovascular Disease

The number of people living with congenital heart disease is rising yearly. Approximately 1 in 300 children is born with significant heart disease that requires intervention in the first month of life. In the United States, there are approximately 35,000 children born with heart disease each year. Secondary to advances in surgery, medicine, and intensive care unit (ICU) care, most of these children live into adult life. There are now as many adults with congenital heart disease as there are children. Long-term considerations for their care and well-being need to be considered too. This section will deal with some of the day-to-day issues that face these patients.

Medical insurance and insurance eligibility issues remain problematic in the current US health care system. The financial stresses and strains placed on families with children with congenital heart disease can be enormous. Health care costs vary internationally but in the United States these issues can be challenging and may negatively impact upon care. In the current system, children, adolescents, and some young adults are covered under their parents’ private insurance group contracts. Dependent care continues until age 18, 21, or 25, depending upon such things as academic or dependent status and the parent’s contract with his or her employer. Some insurance contracts will allow young adults with disability to continue under the parent’s coverage. Even with some form of private health insurance, families still face significant financial hardships with the costs of medicines and needed services. Parents and older patients may decide when, where, and how much to work to simply have access to a certain level of insurance. Families without private health insurance may qualify for state or federal programs. There are many regulations for both initially receiving and maintaining eligibility, and the bureaucratic intricacies can be overwhelming. The children may easily have gaps in their health care coverage.

One major problem relates to adolescents and young adults as they try to transition to independence. Some will simply need continuous financial help from their parents in regard to medical issues. Others, with more severe lesions who can be classified as disabled, may qualify for Medicare and Social Security Disability (SSI). A Web site that may be helpful is www.disabilitysecrets.com/advice.html.

Most children with congenital heart disease can expect to live to be adults; as survival has increased, attention has been diverted towards some of the other important aspects of care, including neurodevelopmental, behavioral, emotional, and psychosocial issues. Improving quality of life issues starts with the fetus. Prenatal diagnosis of ductal-dependent lesions has been shown to improve not only survival but also neurodevelopmental outcomes, as these neonates are less likely to have preoperative metabolic acidosis. At the initial diagnosis of the complex heart disease, the family is overwhelmed; indeed, most if not all families cannot absorb the majority of the information proffered at that time. Prenatal diagnosis gives the family time to prepare and anticipate such things as health insurance, time off work, and childcare. They can have all their support systems in place, and dealing with the issues prior to delivery can significantly lessen the emotional and financial impact on the family and let them concentrate on the more immediate postdelivery issues. The parents and family members are integral parts of the care team. Their emotional wellbeing is important for both short- and long-term care. Several studies have shown that although IQ scores of children with congenital heart disease are generally within the average range, they tend to be lower than in age-matched controls in the normal population. Term newborns with cyanotic heart disease and complex single-ventricle physiology have widespread brain abnormalities before they undergo heart surgery. These abnormalities are not associated with known genetic defects/disabilities that are common in children with congenital heart disease. These genetic issues are additional burdens that affect neurodevelopmental outcomes. It is only recently that a change in hematocrit levels during bypass surgery on infants was found to affect neurodevelopmental outcome. Lower hematocrit levels as part of hemodilution strategies for bypass were associated with lower IQ scores. Children with congenital heart disease tend to have learning difficulties with attention deficit disorder, visual spatial issues, expressive language, or behavior. For patients with hypoplastic left heart syndrome, motor scores appeared to be more effective than cognitive scores at age 1 year.

The main focus at the toddler/preschool age is to anticipate issues in preparation for school and physical activities. As the children enter school, questions regarding the type of learning strategies and the areas of education that need to be stressed become important. The use of medicines for attention deficit hyperactivity disorder (ADHD) must be scrutinized, as these medicines are sympathomimetic and carry a risk of arrhythmia. This is an excellent time to try to steer a child to the appropriate level of physical activities and sports. The concept of health-related quality of life (HRQOL) has been explored in several studies, and many children and parents rate their quality of life in a similar manner to age and gender-match controls. Several predictors have been identified that may be important determinants of HRQOL including the diagnosis of cyanotic heart disease, reduced physical capacity, the use and duration of deep hypothermia and circulatory arrest, and early prenatal distress. Interestingly, in some of these studies, the parents of children with congenital heart disease rated HRQOL lower than their children. As many of these children have been through frequent medical and/or surgical procedures, there is a tendency of parents to be overprotective. Although this is certainly a natural reaction as the child grows and develops, this can have psychologically deleterious effects. It is therefore important to solicit information on activities and to avoid unnecessary restrictions. As children age, body image is also a consideration, as surgical scars and other morphologic differences can be associated with a negative impact on self-esteem. Studies have also shown an increased incidence of depressive symptoms in children with surgically corrected congenital heart disease, compared to their age matched controls. Once again, developing a rational, achievable exercise routine that may involve other family members can be helpful.

As children grow into adolescence and adulthood, concerns other than school performance predominate. These include peer relationships, fear of death, employment, insurance, marriage, contraception, the ability to have children, and the risk of transmission of congenital heart disease. Adolescents becoming independent have their own challenges. A study of heart transplant patients, ages 15 to 31, revealed that more than half of respondents admitted to missing medications or follow-up appointments. In a study of young adults (ages 19 and 20) and adolescents (ages 16–18) with congenital heart disease, more than half of the young adults and more than one-quarter of adolescents reported that in the past 30 days they had either smoked cigarettes, used marijuana or other drugs, or had an episode of binge drinking. More than one-third of adults with congenital heart disease have met Diagnostic and Statistical Manual of Mental Disorders Fourth Edition criteria for either a depressive episode or general anxiety disorder. Adolescents and adults with congenital heart disease do not always tell their doctors the extent of their problems or limitations; in fact, they tend to be ambivalent. One study concluded that they have a strong wish to be healthy, and they may hide their symptoms from the healthcare personnel and sometimes even from themselves. In my own experience, this is very true. Only after one of my teenage patients died did we find out that he had a syncopal episode 2 weeks prior to his sudden death that was witnessed by his siblings, whom he had sworn to secrecy.

Specific screening and testing for children with known heart disease will be covered under the section “Exercise Considerations in Congenital Heart Disease.” In addition, this section will focus more on the high school and college athletes including club sports, as sports participation at this age and level is truly competitive and training is pushed beyond normal endurance. The section will also be limited to cardiac issues and will not include hemoglobinopathies (sickle cell variants), clotting abnormalities, pulmonary causes, or neurologic causes such as cardiovascular accidents (CVAs), and seizures.

Pregnancy and Contraception

Risk stratification for maternal outcomes for pregnancy are limited. Table 500-1 provides our best current practical guidelines for counseling patients regarding risks. Collaborative management by a pediatric cardiologist, or adult cardiologist with experience in congenital heart disease, and a perinatologist is optimal.

Prevention of pregnancy with steroidal birth control increases the risk of thromboembolic events and is contraindicated in patients with residual right-to-left shunts, pulmonary hypertension, and single ventricles with passive pulmonary blood flow. Alternative approaches should be utilized.

Exercise

Physical exertion at some level is beneficial for almost all people, including those with congenital heart disease. The goal is to balance the beneficial effects of increased cardiac work associated with exercise with the risk of disease progression or serious injury and death, which may occur. Making recommendations for the type or extent of physical activity for children with congenital heart disease is quite difficult and secondary to the heterogeneity within defects. In addition, secondary to changes in surgical techniques and the timing of interventions, there is a lack of data in making recommendations for various lesions for which we have not necessarily had enough time to know the long-term risks.

The 36th Bethesda Conference, published in 2005, deals with eligibility recommendations for competitive athletes with cardiovascular abnormalities.1 As such, it does not deal with recreational activities or physical education at school. Generally, sports are broken down into categories based upon the amount of dynamic and static activity (eTable 500.1). All exertion and physical activity can be broken down into these components. Restrictions for patients with congenital heart disease vary depending on the actual increase on myocardial oxygen demands and the physiologic stress placed on the underlying cardiac conditions. For instance, wrestling, a sport with a high static component, is not recommended for patients with moderate or severe aortic insufficiency, as it potentially will increase the amount of leakage. It should also be noted that the exact classification of some sports varies in the amount of dynamic and static components from training to competition. Many sports not considered to have a high static component during competition include training sessions with weightlifting. Training regimens may need to be modified. Different positions in different sports also have very different physical demands. Examples would include goalie versus a midfielder in soccer, a catcher versus first-base player in baseball, and an offensive lineman versus wide receiver in football. In addition, bicycling will vary on whether a ride is level or up hill with an increasing static component as the grade or slope increases. Exercise activities are also classified as to whether there is a collision risk or increased risk secondary to dizziness or momentary loss of coordination. For instance, patients with pacemakers and patients who take anticoagulation agents such as Coumadin or enoxaparin will have restrictions that are not related to myocardial demands.

Patients with cyanotic heart lesions usually restrict themselves, because they become more cyanotic with increasing physical effort. They may participate in physical education at school but must be allowed to rest or stop, and they should not be forced or induced to do any competitive activity, such as running a mile for time or performing so many push-ups or sit-ups. Most children with repaired lesions can participate in all sports. The timing after repair will depend on the type of surgery or intervention. Patients with atrial and ventricular septal defects that are repaired surgically must wait 3 to 6 months before full participation in sports. They should have an echocardiogram and EKG to make sure that they do not have any arrhythmias, pulmonary hypertension, or ventricular dysfunction. Patients with atrial septal defects, especially those closed after childhood, may have tachyarrhythmias as long-term sequelae and should be followed for this possibility. Small atrial septal defects/patent foramen ovales and ventricular septal defects with QP/QS ratios of less than 1.5:1 are not always repaired. These patients are cleared for all activity, except for patients with atrial septal defects and patent foramen ovales who should not scuba dive, secondary to the risk of embolic stroke. Moderate-to-large atrial septal defects, ventricular septal defects, and patent ductus arteriosus are usually repaired either by surgery or interventional catheterization once they are found in children old enough to compete competitively (approximately age 12 years). They can participate in routine exercise, as long as they are allowed to rest and limit their exertion until they are repaired.

Tetralogy of Fallot patients should not compete in any sports until after they are repaired. Their postrepair recommendations depend on right ventricular function, volume and pressure, and on the presence or absence of atrial or ventricular arrhythmias. The right ventricular volume should be normal or only mildly enlarged, and the right ventricular pressure should be less than one-half systemic. They should have exercise stress tests to specifically look for ventricular arrhythmias, because many have had a ventriculotomy as part of the repair.

Asymptomatic patients with aortic stenosis, including subvalvar and supravalvar stenosis, who have mild stenosis, defined as a mean gradient of less than 25 mmHg by echocardiogram or as a peak gradient of 30 mmHg in the catheterization lab, can participate in all sports as long as they have a normal ECG. Asymptomatic moderate aortic stenosis defined as a catheterization gradient of 30 to 50 mmHg or a mean gradient of 25 to 40 mmHg on echocardiogram may participate in some sports, but they will need an echocardiogram/exercise testing prior to approval. Patients with severe aortic stenosis should not participate in competitive sports or in physical education at school, and their level of exercise should be adjusted by a cardiologist. Because all forms of subvalvar, valvar, and supravalvar aortic stenosis tend to progress with time, these patients will need serial follow-up every 1 to 2 years with the possibility of a change in recommendations.

Pulmonic stenosis is very well tolerated, and as long as the right ventricular pressures are less than one-half systemic and the right ventricular function is normal, patients should not have any restrictions. Patients with a peak gradient by echocardiogram of more than 50 mmHg undergo intervention, usually by catheterization. Following intervention, if they have right ventricular pressures less than one-half systemic, good right ventricular function, and only mild pulmonary insufficiency, they can participate in all sports 2 weeks postcatheterization intervention and 3 months postsurgical intervention.

D transposition (simple transposition) patients at present will almost all have had arterial switch repairs. The important caveat to remember here is that their coronary arteries were moved as part of the operation. They should all undergo exercise stress testing prior to approval for competitive sports. Additional sequelae that may affect their ability to participate are supravalvar pulmonic stenosis or supravalvar aortic stenosis and dilation of the neoaortic root. Fontan patients are such a heterogeneous group, that it is difficult to predict how they will react to physical exertion.

Coarctation patients also have their own set of considerations.The first is to remember that they often have other associated lesions, including subaortic stenosis, bicuspid aortic valve, aortic stenosis, and dilated aortic roots that must also be factored into exercise participation. Patients after repair will sometimes have mild residual gradients at rest, a recurrence of a gradient with exercise, left ventricular hypertrophy or systemic hypertension. Patients repaired by stent or balloon angioplasty should have magnetic resonance imaging (MRI) to look for aneurysms prior to competitive sports participation.

Kawasaki disease is now the most common type of acquired heart disease. Aneurysms will develop in 4% of those patients treated with high-dose gamma globulin in the acute phase. The risks of exercise in individuals depend on the degree of coronary involvement. There are two avenues for the development of coronary ischemia from Kawasaki disease. Coronary thrombi may form in large aneurysms and spread distally if the aneurysms do not resolve. Second, since coronary aneurysms represent a vasculitis and damage to the coronary wall, progressive coronary artery stenosis may develop. The limitations are varied, and the most important piece of information to remember is that patients who develop aneurysms need stress testing with myocardial perfusion imaging to delineate their safe exercise levels.

Effects of Altitude

Oxygen delivery to tissues is equal to the oxygen content of the blood times the cardiac output. Exposure to higher altitudes where the partial pressure of oxygen (PO2) and inspired oxygen (PIO2) are reduced, decreases alveolar oxygen (PaO2) as can be calculated from the alveolar gas equation: PaO2 = PIO2 – PaCO2/R + F R is the respiratory quotient, normally about 0.8, and F is the correction factor, usually less than 2 mmHg. The normal PIO2 is about 150 mmHg and is equal to 21% of 760 mmHg (barometric pressure minus 47 mmHg) water vapor pressure. The partial pressure of oxygen (PO2) is determined by barometric pressure, and the barometric pressure decreases as altitude increases. Because the oxygen dissociation curve is S-shaped, it does not show a significant decrease in oxygen saturation until the PO2 is about 60 mmHg.

When there is normal cardiopulmonary function, alveolar oxygen PaO2 is about 100 mmHg. The difference between alveolar and arterial oxygen (AaDO2) is normally less than 15 mmHg, producing arterial PaO2 of at least 85 mmHg and oxygen saturation in the high 90s. In practical terms, up to a level of 3000 feet, there is no response to altitude because there is essentially no change in oxygenation. The oxygen dissociation curve is almost horizontal at this point. The PaO2 at 5000 feet is 82 mmHg, and the oxygen dissociation curve starts to become more vertical at this point, although the slope is shallow. Between 5000 to 10,000 feet (moderate elevation) the slope of the curve is still not steep, but there will be changes of oxygen saturation and initiation of physiologic responses to the decreased oxygen saturation (hypoxia). An elevation of 10,000 feet corresponds to a PaO2 of 62 mmHg. Above 10,000 feet, high altitude, the oxygen dissociation curve is much more vertical, and increases in altitude cause much more precipitous falls in PaO2 and O2 saturation and stronger physiologic responses.

The heart lesions which do not tolerate the physiologic increase in pulmonary vasoconstriction caused by hypoxia (increased altitude) include single ventricles with Fontan circulation, as these patients do not have a ventricle to pump blood to the pulmonary circulation. In general, Fontan circulation patients will tolerate increased altitude if they have an atrial fenestration, but this improved toleration depends on the reason for the presence or continued presence of the fenestration (eg, some centers only fenestrate high-risk Fontans, and these high-risk patients would be expected to do poorly with any added stress). Other patients who have the potential to be affected at moderate altitudes include patients with pulmonary hypertension from pulmonary vascular disease and patients with either severe tricuspid regurgitation (eg, Ebstein anomaly), severe pulmonary insufficiency (eg, tetralogy of Fallot status posttransanular patch repair or with longstanding homograft valves), or both. This intolerance to altitude will be increased if exertional activity is involved, as the reduced alveolar oxygen tension created by exercise may increase pulmonary vasoconstriction.

Patients with cyanotic heart disease and those with Fontan physiology should live below 5000 feet (low altitude) so that there will not be a significant compromise of O2 delivery to the body or a significant increase in pulmonary vasoconstriction. They usually will be able to visit moderate elevations, 5000 to 10,000 feet for short periods, such as airline flights without sequelae. The longer they stay at elevation and the closer the elevation is to 10,000 feet, the more likely they are to develop symptoms and distress. Trips to relatives who live at moderate elevation or family ski vacations should have contingency plans that allow the patient to return to low altitude quickly. Even if they are not symptomatic at rest, their exercise tolerance will likely be affected. Supplemental oxygen will be helpful in alleviating symptoms.

All commercial airlines carry supplemental oxygen, but they have differing policies on the use of supplemental oxygen, and it is wise to contact and arrange ahead of time the O2 delivery system to be used. (In this day and age, expect to be charged a handsome supplemental fee.) Commercial aircraft can maintain a cabin pressure equivalent to sea level or local ground level up to an altitude of 22,500 feet. Above that altitude, cabin pressure will start to decrease, inducing lower arterial saturation/PO2 in the travelers. The maximum altitude allowed is roughly 9000 feet, but at usual cruising altitudes, the cabin pressure is usually 7000 to 8000 feet. Because most flights are of short duration (less than 6 hours) and there is little physical activity, commercial flights are well tolerated. Special consideration for layovers at altitude must be considered in planning travel.

Another travel consideration is the actual altitude to be visited. Most major US cities are listed at elevations near or below 5000 feet (low altitude). Unfortunately, some of the cities at around 5000 feet are situated in mountain valleys, and some of their greater metropolitan areas may be at much higher elevation. For example, Albuquerque is listed at an elevation of 4945 feet, and Salt Lake is listed at an elevation of 4390 feet, but both cities have associated areas of between 7000 and 8000 feet of elevation. Long-term plans for higher education and job selection will also be affected by altitude. In the western United States, some schools are located at high altitudes, and school performance and the possibility of having to be more self-sufficient while away at school can be quite demanding.

Patients with severe tricuspid regurgitation, severe pulmonary insufficiency, tricuspid regurgitation and pulmonary insufficiency, or right ventricular dysfunction will be increasingly affected at increasing moderate elevation. They can be expected to have the same problems as Fontan circulation patients at moderate elevations when they live at high elevations, and they should live below 10,000 feet in elevation. Every patient will vary in their clinical response, so recommendations in medications need to be customized. Most effects of elevation are reversible over time, although subsequent response to hypoxia may be more vigorous.

Patients who should remain at low altitude also include unrepaired tetralogy of Fallot and unrepaired tetralogy of Fallot physiology patients (eg, tricuspid atresia, ventricular septal defect, pulmonic stenosis, and transposition ventricular septal defect pulmonic stenosis, because they are at risk of hypoxic (hypercyanotic episodes). They should not fly or visit moderate or high altitude until they are repaired. The patient with an absent pulmonary artery on the side opposite the aortic arch (a rare condition) should not spend time in elevations above 5000 feet because of the risk of acute pulmonary edema.

Besides supplemental oxygen, there are now other medical options to aid patients who are planning visits to moderate and high altitudes or who have pulmonary vasoconstriction. Phosphodiesterase type-5 inhibitors, such as sildenafil, have a rapid onset of action, and they may be started a few days prior to the expected change in altitude. The endothelin blocker bosentan would not be a good choice, since it does not achieve its maximal effect for weeks or months after institution of therapy. There is also a much higher risk of side effects. Inhaled (nebulized) iloprost a stable analog of prostacyclin is another alternative. Because it is inhaled, side effects are uncommon and include headache, flushing, and most importantly hypotension. The major limitations are the frequency of application, up to 6 times per day, and the need for a nebulizer. The L type calcium channel blocker, nifedipine, is also effective at treating pulmonary edema caused by acute pulmonary hypertension.2-6