Aortic Arch Thrombosis Mimicking Interrupted Aortic Arch

We report a case of a 32-week-gestation male who presented initially with symptoms suggestive of an interrupted aortic arch. The absence of a VSD prompted further investigations, including a CT angiogram, which revealed that he had an extensive thrombus in his aorta. He underwent a successful aortic thrombectomy with arch repair on cardiopulmonary bypass support. In view of the extensive thrombus, the patient was referred to the haematology team. There was no family history of prothrombotic tendencies. 1. Case Report Baby D was born at 32 weeks of gestation via emergency caesarian section following a period of reduced foetal movements. Antenatal scans were normal, and his mother had a relatively uneventful pregnancy until then. There was however a history of previous term stillbirth (no postmortem) and 2 live preterm births who are otherwise well. His mother was not known to have diabetes or be on any medication. There was no risk for sepsis. At birth, he was intubated for poor respiratory effort and received surfactant for prematurity. He was also noted to have some hydropic signs with ascites but no pleural or pericardial effusion. His local paediatric team was concerned when his saturations were not improving with worsening metabolic acidosis, poor lower limb pulses, and blood pressure. Prostin was commenced for a possible duct-dependent lesion, and dobutamine was started for inotropic support. At his worst, his blood lactate was 19？mmol/L in his local hospital. He was transferred to Birmingham Children’s Hospital for a cardiac opinion. In PICU, an initial echo was suspicious of interrupted aortic arch. In view of the absence of a VSD, he had a CT angiogram (Figure 1) that demonstrated an extensive thrombus in his aorta (distal to his left carotid down to his descending aorta). His echo (Figure 2) showed that he had poor left ventricular contractility but no pericardial effusion. Baby D also had a CT head at the same time that revealed extensive intraventricular haemorrhage in lateral, 3rd and 4th ventricles with some subdural bleed. Figure 1: Computed tomography showing the aortic arch which appears to be interrupted with a radiodense lesion distal to the left subclavian artery. Figure 2: Echocardiogram showing the aortic arch with an echobright lesion within the lumen of the aorta just distal to the left subclavian artery. He underwent aortic thrombectomy with arch repair on cardiopulmonary bypass support. The surgery was successful, and he had his chest closed 48 hours later. He received adrenaline and milrinone for inotropic support. His