Giant saccular superior vena cava aneurysm—a rare and difficult clinical case

Abstract

A superior vena cava (SVC) aneurysm is an extremely rare case of vascular malformation in the chest cavity. This is a report of a case of a 57-year-old woman with a saccular SVC aneurysm which was 8 cm wide. The chest computed tomography (CT) scan confirmed a giant 75 mm × 79 mm × 81 mm mass containing the contrast medium from SVC, constricting the right lung parenchyma, narrowing the right innominate vein, in contact with the anterolateral chest cavity wall, and adjoining the superior mediastinum.Under general anesthesia and employing the median sternotomy approach, using a cardiopulmonary bypass (CPB), the venous aneurysm was successfully resected. The postoperative period was uneventful. Radical surgical resection using a sternotomy and a CPB is recommended. and was entirely constricting the right upper lobe of the lung. After the mass was dissected from the right phrenic nerve and the surrounding tissue, we used a vascular clamp to exclude the neck of the aneurism. The mass was detached; the neck of the aneurysm was continuously sutured and strengthened with teflon felt patches (Figure 2).A histopathological examination was conducted and this confirmed that the mass which had been removed was a part of a venous blood vessel. A control CT scan and chest X-ray was done after surgery ( Figure 3). Because of an uneventful postoperative period, the patient was discharged on the 5th day after the procedure. DiscussionA vein aneurysm is an extremely rare phenomenon in medicine. In 1963, Abbot and Leight introduced a classification of aneurysms and divided them into four groups (congenital, acquired, pseudo-aneurysm, and arteriovenous aneurysm) (2). The fusiform aneurysm constitutes the vast majority. In our case we are presenting a saccular aneurysm, which has only been described in literature a few times. Such aneurysms are usually asymptomatic and are usually diagnosed accidentally in routine chest X-rays. Detailed diagnostics include a CT scan or magnetic resonance imaging (MRI). Aneurysms might be congenital, or caused by inflammation or by the degeneration of the vascular wall, but in most cases their cause is unknown (3). They might be solitary or they may coexist with cystic hygromas and angiomas. In asymptomatic patients where the diameter of the aneurysm is less than 40 mm, we might proceed conservatively, using anti-plaque therapy and periodic scans (4). Aneurysms which are larger, growing, symptomatic or containing thrombus require radical surgical treatment (3,5,6). Part of the thrombus forming the sack of the aneurysm can break away and cause pulmonary embolism or lung infarct which may lead to the patient's death (7,8). Particular caution is required in this circumstances. Thanks to CPB, our patient was protected from pulmonary embolism and lung infarct. The use of CPB should be considered not only when the thrombus formation is detected, but also in the case of calcification in the wall of the aneurysm (5). In our opinion, the type of surgical approach presented here gives better insight ...

Clinics in diagnostic imaging (194)

“…It has been suggested that asymptomatic aneurysms with diameters < 40 mm can be managed conservatively with periodic scans and anticoagulation. (4) This is especially so for fusiform aneurysms that have lower complication rates. (5) Thrombolytic therapy with recombinant tissue plasminogen activator was deemed to be harmful in one case, in which mobilisation of the thrombus in the SVC aneurysm resulted in recurrent pulmonary embolism.…”

“…(3) Surgical resection, usually through a median sternotomy approach, has been advocated for saccular aneurysms due to risks of complications, (1) and for aneurysms that are larger than 40 mm, growing or symptomatic, or those that contain thrombi. (4) Cardiopulmonary bypass should be used when operating on saccular or complex aneurysms, such as those with venous obstruction, calcification or thrombus formation, to prevent pulmonary embolism. (4,6) Endovascular approaches can be considered for patients with high surgical risk.…”

“…(4) Cardiopulmonary bypass should be used when operating on saccular or complex aneurysms, such as those with venous obstruction, calcification or thrombus formation, to prevent pulmonary embolism. (4,6) Endovascular approaches can be considered for patients with high surgical risk. In one case report, a stent was deployed into the SVC and stent meshes were then used for coil occlusion of the neck of the aneurysm sac.…”

A Rare Case of Superior Vena Cava Saccular Aneurysm

“…The exact mechanism by which these aneurysms form has not been elucidated, but suggested theories include congenital abnormalities, inflammation, infection, mechanical trauma, and pathologic deficiencies of the SVC longitudinal muscle wall adventia. [3][4][5] An association with cystic hygromas has been suggested because of the similar embryologic origins of the venous and lymphatic systems. 3 Often, the exact etiology of SVC aneurysms cannot be confirmed.…”

A saccular superior vena cava aneurysm with unique diagnostic computed tomography findings

“…We therefore subsequently started anticoagulant therapy in the present case. The treatment strategy for SVC aneurysms has not been established; however, a recent report suggested that asymptomatic aneurysms <40 mm in diameter might be best approached with conservative observation and anticoagulant therapy 4.…”