A 73-year-old female presented as an outpatient from her primary care physician for a CT of the thorax, abdomen, and pelvis to evaluate a reportedly stable abdominal aortic aneurysm. Pertinent past medical history revealed a left supraclinoid internal carotid artery aneurysm, a stable infrarenal abdominal aortic aneurysm, systemic lupus erythematous/rheumatoid arthritis overlap syndrome, smoldering IgG lambda myeloma, chronic kidney disease (stage II), hyperparathyroidism, and a cerebral infarction in the right posterior cerebral artery territory in 2009. Findings on the CT of the thorax demonstrated a fusiform superior vena cava (SVC) aneurysm measuring 5.9 × 4.4 × 6.1 cm (anterior-posterior × transverse × craniocaudal). No thrombus was noted within the SVC aneurysm (). The aneurysm was first partially visualized in 2007 on a cervical spine CT, and since that time it had remained stable on annual follow-up CTs.\nThe patient's course between 2007 and the most recent study in 2016 included an extensive rheumatologic and hematologic workup, including a temporal artery biopsy in 2015. Pathology revealed intimal hyperplasia with focal internal membrane disruption, but no features of granulomatous vasculitis were identified.\nThe etiology of the SVC aneurysm in this patient is uncertain. Potential causes in this patient include autoimmune disease (RA/SLE), which seems unlikely. Pathology did not reveal any convincing evidence of vasculitis. The arterial aneurysms are also felt to be unrelated as the patient has significant atherosclerotic disease. While an iatrogenic cause is possible, a chart review did not elicit any complications relating to prior hemodialysis catheter placement. Therefore, we surmised that the SVC aneurysm was likely idiopathic.\nThis patient did not receive any anticoagulation to prevent thrombus formation within the SVC aneurysm, and no repair was ever attempted. For the six years during which the patient was under observation at our institution, an SVC thrombus or sequela of an embolus originating from the SVC has never been observed. While the patient had a cerebral infarct in 2009, there was no evidence of right to left circulatory shunt. The observatory management of the SVC aneurysm in this patient stands in contrast with the majority of the cases found in the literature. Most patients were treated prophylactically for theoretical complication.
A 42-year-old female was referred to the outpatient department, with features suggestive of lower respiratory tract infection. Physical examination was unremarkable. She had no history of any cardiac disease or injury to thoracic cage. She had no history of antecedent serious illness. Family history was also non-contributory.\nChest X-ray was done for the workup of respiratory symptoms, which showed abnormal contour and widening of right border of mediastinum (). In chest X-ray, the cervico-thoracic sign and hilum overlay sign were present in posteroanterior (PA) view. Lateral view showed anterior bulging of mediastinum.\nComputed tomography (CT) of thorax was done for further workup in angiographic protocol which was suggestive of aneurysmal ectasia of SVC and patchy consolidation of right lower lobe. Aneurysmal ectasia of SVC measuring 4.5 × 5.5 cm in maximum dilatation and for a length of 8.9 cm without internal thrombosis or dissecting flap was present ( and ). No other vascular anomalies were detected.\nSince CT did not reveal any signs of obstruction, we believe that the SVC aneurysm is primary and can be classified as congenital primary superior vena caval aneurysm (CPSVCA), class 1A as per Abott’s classification (1964) [].