Aortic thrombosis in infancy.

A 33-day-old female was admitted to hospital with the diagnosis of viral bronchiolitis. The physical examination performed after treatment with bronchodilators revealed a grade 2/6 systolic ejection murmur at the left upper sternal edge. The arterial pulses and blood pressure in all extremities were normal. The two-dimensional echocardiogram revealed a mass measuring 3.5 x 3.5 cm at the ductus level consistent with a thrombus; there was flow acceleration at the level of the proximal descending aorta with no significant gradient. All other laboratory tests were normal except for an elevated platelet count. The infant was treated with subcutaneous enoxaparin and oral aspirin for four months and nine months, respectively Progressively the clot became smaller, however still visible at last evaluation at age of 12 months. Her growth and development remained normal. Aorticthrombosis in neonates and young children is uncommon. Until 2000 only 63 cases had been reported in the English literature. Spontaneous aortic thrombosis is rare. A 20-year literature review in 2006 yielded only 12 such cases. The clinical presentation is variable and the prognosis can be life threatening. The prognosis depends on the size and location of the thrombus, the underlying cause, delay in reaching a diagnosis, and the treatment modality.