EVALUATION AND DIAGNOSIS
Cardiomyopathy can be a challenging disease to diagnose because it is not easily detected during a routine examination by a pediatrician or general practitioner. Symptoms may not exist or be noticeable in the early stages of the disease. With young children, cardiomyopathy can be difficult to diagnose because they are unable to clearly communicate how they feel. It is not uncommon for cardiomyopathy to be inadvertently missed in children who have no heart-related illness, family history of the disease, or physical signs of the disease.
Some children are diagnosed following the detection of a heart murmur or other abnormal physical findings during their well-child visit. Because cardiomyopathy is rare in young children, symptoms may get misinterpreted as asthma, pneumonia, acute bronchitis, respiratory distress, gastrointestinal disease, or even a cold or flu. If symptoms persist, a chest x-ray or an appointment with a pediatric cardiologist will be suggested. Since cardiomyopathy can be a progressive disease, early detection, proper diagnosis, and targeted treatment are critical to a successful outcome.
A formal diagnosis is made by a pediatric cardiologist, who will perform an echocardiogram and an electrocardiogram. An echocardiogram (echo) is an ultrasound image of the heart that is used to determine if there is any abnormal thickening or enlargement of the heart. An electrocardiogram (EKG), a recording of the heart’s electrical activity, is used to detect abnormal heart rhythms. Other non-invasive or invasive tests may be performed based on the child’s heart condition.
As part of the evaluation process, blood and urine samples will be collected. Additional laboratory testing may be recommended when an infant or young child is diagnosed with severe or progressive cardiomyopathy. Additional testing may be needed to screen for viral infections or systemic conditions that affect multiple organs. Rare diseases associated with cardiomyopathy include Barth syndrome, Noonan syndrome, Duchene muscular dystrophy, and inherited metabolic or mitochondrial diseases.
If the cardiomyopathy is found to be viral in nature, screening of family members will not be necessary. With confirmed inherited metabolic disorders, a change in diet, specific supplements (carnitine), or a blood and marrow transplant may be considered.
For a child who has an inherited form of cardiomyopathy, an echo and EKG test will be recommended for parents and siblings. Even if the screening results are normal, the cardiologist may still advise family members to be rescreened every few years. A family member could carry a cardiomyopathy-causing genetic mutation but has not developed the disease yet. In this case, it is possible for cardiomyopathy to resurface later in life with or without symptoms. If additional family members are found to have cardiomyopathy, screening outside of the immediate family (grandparents, aunts, uncles, cousins) should be considered.
Individuals with a family history of cardiomyopathy have been advised to have an echocardiogram and EKG every 1 to 3 years before age 12, and then more frequently from age 12 to 21. If by early adulthood, cardiomyopathy has not developed, screening most likely can be stopped. Certain individuals older than age 21 may be advised to continue screening every five years if late onset cardiomyopathy has occurred in their family. These screening guidelines may be adjusted on an individual basis by your cardiologist.
Genetic testing is another option to consider when there is a family history of cardiomyopathy. Genetic testing can identify a disease-causing mutation in a diagnosed child. This finding can then be used to test other family members and assess their risk for developing cardiomyopathy. The test results will provide guidance on which family members can discontinue screening and which members require more careful monitoring. The geneticist and cardiologist will work together to review the laboratory results and develop an appropriate treatment plan. They will also advise on how to manage screening of family members going forward. For more information on genetic testing, visit the Genetic Testing webpage.