(763) Pulmonary Embolism From Right Ventricular Myxoma in a Child With Undiagnosed Carney Complex

Introduction: Pediatric pulmonary embolism occurs in 8.6-57 per 100,00 hospitalized children. We report a novel case of bilateral pulmonary emboli in a child presenting with dyspnea who was found to have large right ventricular myxoma and a new diagnosis of Carney Complex.

Description: A 14-year-old female presented to the hospital after two days of shortness of breath and pleuritic chest pain. She was not hypoxic but was tachycardic for age. An elevated D-dimer of 8,000 ug/L prompted chest computed tomography which showed large bilateral pulmonary emboli. Echocardiogram demonstrated a large mass (3x3x7cm) in the right ventricle extending through right ventricular outflow tract, right ventricular dilation, and normal function. Additional laboratory results showed a normal white blood cell count, hemoglobin, and platelet count. Inflammatory markers were elevated, including C Reactive protein of 10 mg/dL and fibrinogen of 810 mg/dL. Systemic heparin was started and she was transferred to a pediatric heart center. On further review of past medical history, she had a pituitary adenoma resected 3 years prior. She was conceived by donor egg so no maternal familial history was able to be obtained but paternal family history was unrevealing. On physical examination, she had multiple abnormal cutaneous and mucosal lentigines. Cardiac magnetic resonance imaging showed a large, mobile right ventricular mass with attachment to the mid-cavity wall/tricuspid support apparatus and a mass in the right pulmonary artery bifurcation. The following day she had a right ventricular myxoma resection and bilateral pulmonary embolectomy. She did well postoperatively and was discharged home on hospital day 4 with the diagnosis of Carney Complex (multiple endocrine neoplasia, lentiginosis syndrome, cardiac myxomas, endocrine/non-endocrine tumors). Genetic testing was sent for PRKAR1A gene sequencing and deletion/duplication studies.

Discussion: Pediatric pulmonary embolism due to cardiac myxoma is rare with most cardiac myxomas occurring in the atria. To our knowledge this is the first pediatric case of Carney Complex presenting with bilateral pulmonary embolism. A high index of suspicion, careful examination, and early diagnostic imaging resulted in a clear diagnosis and an excellent outcome.