Cardiac Care of the Adult with Down Syndrome
Daphne T. Hsu, MD
Professor of Pediatrics, Albert Einstein College of Medicine
Director, Montefiore Adult Congenital Heart Disease Program
Chief of Pediatric Cardiology and Co-Director of the Pediatric Heart Center, Children’s Hospital at Montefiore
Congenital Heart Defects in Down Syndrome
About 50% of babies born with Down syndrome will have some form of a congenital heart defect. Congenital heart defects result from disruption of the normal development of the heart chambers, valves and/or arteries in the first three months of pregnancy. These defects are diagnosed by performing a heart ultrasound (echocardiogram) during pregnancy or shortly after birth. Babies with significant heart defects often develop clinical signs and symptoms including a heart murmur, low oxygen level (cyanosis), fast breathing, or difficulty feeding and growing. The majority of babies with Down syndrome will need to have one or more surgical or catheterization interventions early in life to counteract the effects of the congenital heart defect and allow the child to grow and develop. Over the past 20 years the results of surgery and catheter-based interventions for congenital heart defects have improved dramatically, to the point where the vast majority of patients are now expected to survive to adulthood. As a result of these remarkable improvements, the cardiac care of adults with Down syndrome and congenital heart disease plays an important role in allowing Down syndrome patients to maintain a good quality of life as they age.
Late Effects of Congenital Heart Defects
Interventions to treat congenital heart defects are performed with the goal of normalizing blood flow through the heart and improving heart function. The interventions performed are tailored to the specific type of congenital heart defect present. In broad strokes, interventions to correct congenital heart defects include establishing normal connections by closing or opening holes between heart chambers, redirecting blood to and from major arteries and repairing or replacing narrowed or leaking valves. In some cases, bioprosthetic or artificial materials are used to achieve these goals. While interventions for congenital heart defects result in remarkable clinical improvements, patients with repaired congenital heart defects can develop symptoms from cardiac issues as they age. Thus, all patients with congenital heart disease, particularly those with Down syndrome, require regular heart monitoring throughout their life.
Cardiac Issues in Adult Patients with Congenital Heart Disease
The cardiac issues that arise in adults with congenital heart disease fall into four main categories:
- Residual congenital heart lesions: leaking valves, narrow arteries, residual holes in the heart, or undersized heart structures because of growth failure
- Heart dysfunction: impaired pumping or filling of the heart
- Arrhythmias: tachyarrhythmias (too fast) and bradyarrhythmias (too slow)
- Adult-onset heart disease: hypertension, stroke, coronary artery disease
If one or more of these issues arise, they can lead to symptoms of heart failure such as fatigue, exercise intolerance, trouble breathing, edema, poor weight gain, dizziness or fainting.
CoMorbidities in Adult Patients with Congenital Heart Disease
Patients with congenital heart defects can have abnormalities of organ function that may exacerbate cardiac issues. In patients with Down syndrome, obstructive sleep apnea is common and can contribute to heart failure by causing high pressures in the lungs and worsens symptoms of fatigue and exercise intolerance. Scoliosis is common in patients with congenital heart disease and can impair lung function and negatively affect exercise tolerance. Lung function can also be impaired due to restrictive lung disease following a sternotomy or thoracotomy. Neurologic issues such as a stroke or transient ischemic attack can occur in patients who have a residual hole in the heart because the hole allows a clot to travel from the right to the left side of the heart and then to the brain. Kidney function may be impaired in the patient who has undergone open heart surgery or has heart failure and can worsen water retention. Liver disease such has hepatic cirrhosis or hepatocellular carcinoma has recently been recognized as an important noncardiac complication of elevated right heart filling pressures. Obesity, type 2 diabetes, polycystic ovary disease can accelerate the development of adult-onset cardiac diseases.
Monitoring of the Adult Patient with Congenital Heart Disease- Who, What, Where and When?
Who: As an increasing number of patients with congenital heart defects survive into adulthood, the need for subspecialists with expertise in the issues facing the adult with congenital heart disease has grown. Recently, fellowship training programs for adult or pediatric cardiologists who have an interest in adult congenital heart disease have been established with a focus on improving the long-term outcomes of congenital heart disease by establishing methods to best evaluate and treat affected patients. Subspecialty board certification in adult congenital heart disease is now offered by the American Board of Internal Medicine to those who have completed a fellowship. Currently number of cardiologists who have completed fellowship training programs is small and unable to meet the growing needs of adult congenital heart disease patients. Luckily, a cadre of adult and pediatric cardiologists who have longstanding clinical expertise in the care of congenital heart disease patients is also available to provide care to this population.
What: Monitoring of the patient with adult congenital heart disease includes:
- Detailed history and physical examination
- Noninvasive imaging (echocardiography, cardiac MRI, cardiac CT) to assess the function of the heart and the presence and severity of residual lesions
- Arrhythmia evaluation with an electrocardiogram, 24-48 hour Holter monitoring and longer term rhythm monitoring
- Exercise stress testing
- Invasive testing such as cardiac catheterization, electrophysiology testing
Decisions regarding the frequency and modes of testing that should be performed is dependent on the type of congenital heart disease, the presence of risk factors, and the severity of the clinical signs and symptoms. If a surgical or catherization-based intervention is being considered, more extensive testing including cardiac catheterization and/or electrophysiology testing is often performed.
Where: Adult patients with congenital heart disease and in particular those who have undergone surgical or catheter-based intervention often receive their care at centers that offer these interventions. The Adult Congenital Heart Disease Association maintains a database of adult congenital heart disease programs and the services offered at the programs (https://www.achaheart.org/your-heart/clinic-directory/). If a patient is geographically remote from an adult congenital heart disease program, patients may benefit from a “spoke and wheel” arrangement where the routine cardiac surveillance (clinical history, echocardiogram, electrocardiogram, rhythm monitoring, exercise stress testing) is provided by a local cardiologist with close review and collaboration with subspecialists in advanced imaging, cardiac catheterization, arrhythmia treatment, congenital heart disease surgery and heart failure at a comprehensive adult congenital heart disease program.
When: The American Heart Association and American College of Cardiology recently published the 2018 Guideline for the Management of Adults with Congenital Heart Disease (Journal of the American College of Cardiology VOL. 73, NO. 12, 2019). This extensive document outlines the rationale and general principles for the overall evaluation and management of patients with congenital heart defects and makes specific recommendations for timing and testing for each congenital heart defect. This guideline serves as an excellent roadmap for care for the adult congenital heart disease patient, however specific plans should be modified and tailored to individual patient’s needs and situation.
Treatment of Adult Patients with Congenital Heart Disease
The goals of treatment for cardiac issues in adult patients with congenital heart disease fall into several categories.
- Symptom relief: Symptoms of heart failure can develop in adults with congenital heart disease and are most commonly the result of fluid retention or inadequate delivery of oxygen to the tissues. Fluid retention can be managed with the use of a diuretic to increase urine output. In patients with fatigue and an inadequate cardiac output initial treatment involves intravenous medications to acutely improve heart function, followed by neurohormonal blockade if the underlying issue is cardiac muscle damage. Surgical or catheter-based intervention is indicated if the underlying issue is a residual congenital heart defect.
- Arrhythmia management: Patients with tachyarrhythmias can develop heart failure or syncope and are treated initially with antiarrhythmic medications chosen, based on the type of arrhythmia present. Catheter ablation, if successful, can offer a more definitive therapy for arrhythmia control. An anti-tachycardia pacemaker or implantable cardiac defibrillator (ICD) are also effective interventions to manage significant atrial or ventricular tachyarrhythmias. Patients with bradycardia can present with heart failure because the heart rate cannot keep up with demand. Pacemaker placement to increase the heart rate is often the treatment of choice.
- Correction of residual defects: Surgical or catheter-based intervention for residual lesions are performed to relieve symptoms or may be performed in the asymptomatic patient to prevent a progressive decline in heart function. Decisions regarding invasive intervention requires the clinician and patient to critically evaluate the goals of treatment and carefully weigh the risks and benefits of the potential intervention against conservative management.
- Management of end-stage heart failure: Adult patients with congenital heart disease can develop primary heart muscle dysfunction that is not caused by a residual heart lesion. If unresponsive to medical therapy, patients can be considered for a mechanical heart (ventricular assist device) or heart transplant procedure.
- Prevention or treatment of adult onset cardiovascular disease: As patients with congenital heart disease age, they are not immune to the development of adult-onset cardiovascular disease. Literature has suggested that Down syndrome patients may be less predisposed to the development of coronary artery disease. Nonetheless, interventions that can reduce obesity, manage hypertension and avoid type 2 diabetes should be implemented.
- Pregnancy: Pregnancy results in a significant increase in circulating blood volume in order for the maternal circulation to support the fetus. At the time of delivery there are also significant changes in blood pressure and volume that occur. In patients with certain types of congenital heart defects, an increased volume load and pressure load can lead to the development of heart failure and/or arrhythmias. Pre-conception counseling is essential to decide if the initiation of medical, surgical or catheter-based interventions prior to pregnancy are indicated. During pregnancy, the management of the pregnant patient with congenital heart disease should be multidisciplinary with participation from obstetrics, nursing, cardiology, anesthesia, and neonatology.
- Pulmonary hypertension: Although decreasing in frequency, pulmonary hypertension remains an important cause of morbidity and mortality in the adult congenital heart disease patient. Management strategies include removing the stimulus to pulmonary hypertension, treatment with pulmonary vasodilators, and in rare cases heart-lung transplantation. Patients with pulmonary hypertension should have careful management at adult congenital heart disease specialty centers.
Special Treatment Considerations for the Adult with Congenital Heart Disease
- Exercise: Patients with significant residual lesions, heart failure or pulmonary hypertension do require exercise restrictions. For the majority of patients with mild or repaired congenial heart defects, exercise restrictions are rare in patients and recreational sports are encouraged because of the benefits of decreasing risk factors for adult-onset cardiovascular disease. Patients with Down syndrome who do not have pulmonary hypertension should be encouraged to exercise regularly.
- Endocarditis prophylaxis: The recommendations for the use of antibiotics for endocarditis prophylaxis were revised in 2007. The use of antibiotic prophylaxis was limited to select groups of patients at high risk for infective endocarditis. These groups included patients who have prosthetic valves or prosthetic material used in a valve repair, patients who have had endocarditis in the past, patients who have low oxygen saturation, patients who have undergone placement of patch material in the heart within six months and patients who have undergone a heart transplant and have a valve abnormality.
- Dental Care: Regular dental cleaning is recommended for all patients with particular attention to those patients in the groups at high risk for infective endocarditis listed in the previous section.
- Diet: No particular dietary restrictions are recommended for patients with congenital heart disease. A heart-healthy diet that maintains an ideal body weight and prevents type 2 diabetes and hyperlipidemia is recommended. Patients who are taking warfarin should follow a diet that limits or standardizes intake of Vitamin K rich foods.
Cardiac Care of the Adult with Down Syndrome: Summary
The success of cardiac surgery and catheter-based interventions in the management of the Down syndrome patients with congenital heart defects has resulted in a remarkable increase in the number of Down syndrome patients who are living well into their adult years. Regular follow-up care by a specialist in adult congenital heart disease should be life-long. Routine surveillance for the presence of heart failure or arrhythmia has the potential to identify issues before they become clinically important. Treatment decisions should be made based on a careful assessment of the potential risk and benefits of all the potential options.
Daphne T. Hsu, MD
Professor of Pediatrics, Albert Einstein College of Medicine
Director, Montefiore Adult Congenital Heart Disease Program
Chief of Pediatric Cardiology and Co-Director of the Pediatric Heart Center, Children’s Hospital at Montefiore
3415 Bainbridge Avenue
Bronx, New York 10467
Phone: 718-741-2538
FAX: 718-920-4351
Email: dhsu@montefiore.org