Cardiac Aspects of Pediatric Sports/Exercise Participation
Chest pain in children can be one of the most frightening symptoms encountered by a medical professional. The causes and clinical manifestations of chest pain in this age group fall into the categories of: idiopathic, musculoskeletal, psychogenic, respiratory, gastrointestinal, cardiac and miscellaneous. Although cardiovascular causes of chest pain are uncommon, accounting for less than 5 percent of the cases in children and young adults, they are potentially the most serious.
Deborah Heart and Lung Center developed a program for those most likely to initially encounter pediatric chest pain - school and pediatric office nurses. Attendees learned to recognize indicators of potential cardiac disease in children who appear to be "normal" and discussed cardiac abnormalities that may interfere with safe athletic participation.
"The primary goal of any preparticipation screening should be the identification of pre-existing cardiovascular abnormalities that may threaten the well-being of the pediatric athlete," said Niels G. Giddins, M.D., Chair of Pediatric Cardiology, Deborah Heart and Lung Center. "Although the risk of athletic death is relatively small, early detection of clinically significant heart disease may permit life-prolonging interventions."
Intense athletic training is likely to increase the risk for sudden cardiac death in athletes with clinically important structural heart disease. Cardiovascular disease and/or defects account for 85-95 percent of sudden death in athletes.
"It is important to remember that an athlete is anyone involved in physical activity," said Virginia Bliszcz, CCRN, Pediatric Intensive Care Unit, Deborah Heart and Lung Center. "A child involved in intramural sports, recess and gym class is involved in athletic activity."
For preparticipation screenings, the AHA recommends a complete patient and family history, a complete physical exam for cardiac disease, screening before all high school and collegiate sports and avoidance of routine use of noninvasive testing. During the history, physicians should note signs of abnormal symptoms: excessive shortness of breath or fatigue during normal activities, syncope, near-syncope and/or chest pain during physical exercise.
"While most pediatric chest pain can be attributed to factors other than cardiac, when combined with other physical symptoms and a family history of significant cardiovascular disability or death in individuals younger than 50, it can signify a cardiovascular problem," said Bliszcz. "A family history of other conditions such as hypertrophic cardiomyopathy, long QT syndrome, Marfan's Syndrome and arrhythmias should alert a physician to look more closely at cardiac issues during the physical exam."
The cardiovascular physical examination should include cardiac auscultation in supine and standing positions, chest and femoral artery pulse assessment, brachial blood pressure measurement and recognition of stigmata of Marfan syndrome.
Questionable results from a preparticipation screening should prompt referral to a pediatric cardiologist who can then make the proper diagnosis and recommendation for exercise and sports participation.
If a pediatric patient is found to have cardiovascular disease, recommendations for athletic participation were outlined by the 26th Bethesda Conference(1). The Conference details various types of cardiovascular disease and defects, including hypertrophic cardiomyopathy, the most common cause of sudden cardiac death. It goes on to explain the level of physical activity appropriate for each.
"One thing the Bethesda Conference did was to classify physical activity by type, dynamic or static, and intensity, low, moderate or high," said Bliszcz. "Each category of activity affects the cardiovascular system differently and may influence recommendations for participation."
Dynamic activity involves changes in muscle length and joint movement with rhythmic contractions that develop relatively small intramuscular force. Static involves development of a large intramuscular force with little or no change in muscle length or joint movement. Combining the type of activity with the level of intensity provides a reference to limitations on sports participation. Some cardiovascular patients may be able to participate in a high static, low dynamic activity such as rock climbing; others, a low static, high dynamic such as tennis.(2)
Through cooperation between the physician, patient, family and school/team and through continued monitoring of any cardiovascular disease, most pediatric patients will be able to participate in physical activity.
Niels G. Giddins, MD., Chair, Pediatric Cardiology
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Clinical Trial Examines ICD Therapy in High-Risk Patients
Cardiologists at Deborah Heart and Lung Center are currently participating in MADIT II (Multicenter Automatic Defibrillator Implantation Trial). MADIT II is the second phase of a randomized, FDA-approved trial examining the use of implantable cardioverter defibrillators (ICD) in moderately high-risk coronary artery disease patients with advanced left ventricular dysfunction or ventricular tachycardia. According to Raffaele Corbisiero, M.D., Attending Electrophysiologist at Deborah, "The study is designed to determine if ICD therapy will improve survival and reduce mortality in the ICD-treated patients verses medicinally-treated patients."
The original MADIT I trial, initiated in 1994, substantiated the ability of the implanted defibrillator to save lives in a more narrowly-focused, high-risk population
The study was terminated early when it was found that the ICD group had a 54 percent better survival than the medically treated group.
Sudden cardiac death remains a major unresolved public health problem in the United States and throughout the world. It is estimated that 450,000 people in the United States alone succumb to sudden cardiac death annually, and 80-90 percent of these events are caused by ventricular fibrillation (VF), a very fast ventricular arrhythmia. Without treatment, VF can cause the heart to stop and deplete the brain and body tissue of oxygen-rich blood, resulting in damage or possible death.
Past attempts to prevent sudden cardiac death and reduce mortality in patients with chronic heart disease using pharmacological agents have been unsuccessful in randomized trials involving type I antiarrhythmic agents, Sotalol and Amiodarone.
"We are attempting to identify and treat high-risk patients before they have an event," said Dr. Corbisiero. "We know that in patients who have a history of severe heart rhythm problems and have had prior events, the likelihood of it happening again is very high. The goal of MADIT II is to identify and treat these patients before sudden death occurs."
The MADIT II population consists of patients with one or more prior documented myocardial infarctions. Approximately 720 patients will be randomly assigned to the transvenous ICD and 480 patients will be assigned to no ICD. Deborah Heart and Lung Center currently has 20 patients enrolled in MADIT II, making it number one in the country.
In recognition of the importance of cost considerations in the evaluation of new technologies and the role that such information will play in both clinical and health policy decisions in the future, an economic study was conducted as part of the original MADIT study. The MADIT Cost Effective Study (CES) was unique in its design as a prospective, randomized trial in which comprehensive health utilization and cost-of-care data were collected from patients during the entire length of the study.
"The findings from MADIT CES indicated that the use of an implantable cardiac defibrillator represents a relatively modest investment in terms of years of life saved in selected individuals at high-risk for fatal cardiac arrhythmias," stated Dr. Corbisiero.
As the MADIT trial is ongoing, no conclusive findings have been reported as of yet, however, according to Dr. Corbisiero, the belief is that the prophylactically implanted defibrillator will prove extremely beneficial for high-risk patient groups. Once proven, all high-risk patients will receive defibrillators as a preventative measure.
According to Dr. Corbisiero, "MADIT II is the best and most dramatic example of the benefits of preventative medicine and technology."
Raffaele Corbisiero, MD
Attending, Department of Electrophysiology
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