A 33‐month‐old girl presented with failure to thrive. She initially presented to another hospital with cough and fever and was placed on azithromycin for presumed pneumonia. A history of poor weight gain prompted transfer to our hospital. Upon arrival, questioning revealed normal past medical and developmental histories, but a review of systems was positive for decreased energy and difficulty keeping up with her peers when active. On physical exam, she was afebrile with normal vital signs and appeared small for her age. The remainder of her exam was unremarkable. Prior growth charts showed a decline in weight from the 50th percentile at birth to less than the third percentile by 9 months of age, where she remained. Laboratory studies, including a comprehensive metabolic panel, thyroid function tests, Vitamin D level, urinalysis, stool alpha‐1‐antitrypsin, stool fat analysis, and sweat chloride test were normal. A complete blood count and iron studies were consistent with mild pancytopenia and iron deficiency anemia. A chest X‐ray showed a slightly enlarged cardiac silhouette. Given poor oral intake and decreased urine output, she was treated with intravenous fluids. Within 48 hours, she developed respiratory distress. Her liver edge became palpable 3 centimeters below the right costal margin. A repeat chest X‐ray was consistent with pulmonary edema and a basic natriuretic peptide was elevated. She was placed on oxygen and given intravenous furosemide with symptomatic improvement. An echocardiogram demonstrated markedly dilated atria and decreased biventricular systolic function, consistent with restrictive cardiomypathy (RCM). She was placed on a milrinone infusion and ultimately underwent orthotopic heart transplantation.
RCM is the least common cardiomyopathy in children, accounting for only 2.5‐5% of diagnosed cardiomyopathies. It is usually idiopathic in children; however, associated genetic mutations are known and a family history may be present. RCM is characterized by rigid ventricles with abnormal relaxation. Though ventricular function remains intact, forward blood flow and ventricular filling are restricted, leading to dilated atria and symptoms of heart failure. Echocardiogram demonstrates marked enlargement of the atria, normal sized ventricles, and normal heart function. Diagnosis is confirmed by cardiac catheterization. Cardiac biopsy may reveal infiltrative causes such as amyloidosis or sarcoidosis, though these findings are rare in children. Complications include arrhythmias, failure to thrive, congestive heart failure, and sudden death. Medical therapies include diuretics and anti‐coagulation. Heart transplantation is currently the only known definitive treatment of RCM.
In children presenting with failure to thrive, clinicians must maintain a cardiac etiology on the differential regardless of age at presentation, particularly when signs and symptoms of heart failure are present.
To cite this abstract:Rajput S, Stojan J. Getting to the Heart of the Matter: Restrictive Cardiomyopathy Presenting As Failure to Thrive. Abstract published at Hospital Medicine 2014, March 24-27, Las Vegas, Nev. Abstract 279. Journal of Hospital Medicine. 2014; 9 (suppl 2). https://www.shmabstracts.com/abstract/getting-to-the-heart-of-the-matter-restrictive-cardiomyopathy-presenting-as-failure-to-thrive/. Accessed March 31, 2020.