B2 Thymoma with Intracardiac Extension Presenting as Superior Vena Cava Syndrome: Case Report and Literature Review.

Case 1: A 34-year-old previously healthy male office manager was admitted with acute onset of heaviness, pain, and functional impairment of his right arm. The arm was cyanotic and massively swollen (Figure 1). For the past weeks, he reported transient paresthesia of his right arm during overhead activities and was unable to perform repetitive or strenuous arm exercise. He had a fracture of the right clavicle after a ski accident 5 years previously. The fracture was managed conservatively. There was no personal or family history of thrombosis. Conventional phlebography confirmed axillary and subclavian vein thrombosis (Figure 2, top), and treatment with intravenous unfractionated heparin was started. Figure 1. Clinical presentation of case 1 with massive swelling and cyanosis of the right arm (left). One day after pharmacomechanical thrombolysis, signs of thrombosis have markedly improved (right). Figure 2. Baseline digital subtraction venogram from case 1 with extensive filling defects in the axillary subclavian veins (top). Control venogram after 15 hours of pharmacomechanical thrombectomy confirmed resolution of filling defects and restored venous flow (middle). Positional venography obtained during abduction of the right arm confirmed the venous thoracic outlet syndrome with residual stenosis of the subclavian vein at the costoclavicular junction (white arrow, bottom). Case 2: A 55-year-old man with lung cancer presented with swelling, heaviness, and pain in his left arm 1 week after completion of chemotherapy administered via a left-sided indwelling central venous catheter. Axillary and subclavian vein thrombosis was confirmed by ultrasonography. Low-molecular-weight heparin (LMWH) was initiated, and the catheter was removed 3 days later because it was no longer functional. At 1 week, pain and functional impairment had not improved, and the circumference of the left upper arm had increased by 2 cm. Case 3: A 65-year-old woman with metastatic ovarian cancer presented with swelling of the face and both arms, headache, …

INTERESTING RADIOGRAPHIC FINDING OF SVC SYNDROME DUE TO PRIMARY LARGE B-CELL LYMPHOMA

Artificial reconstruction for a thymoma invading superior vena cava

SUPERIOR VENA CAVA SYNDROME DUE TO A MEDIASTINAL MASS WITH RIGHT ATRIAL INVOLVEMENT

Superior vena cava syndrome (SVCS) is usually caused by extrinsic compression or invasion of the superior vena cava (SVC) by malignant tumors involving mediastinal structures. Although thymomas are well-known causes of SVCS, cases of SVCS caused by malignant thymomas protruding into adjacent vessels draining the SVC with thrombosis have been very rarely reported worldwide. We experienced a 39-year-old female patient with SVCS that developed after the direct invasion of the left brachiocephalic vein (LBCV) and SVC by an anterior mediastinal mass with a high maximum standardized uptake value on the chest computed tomography (CT) and positron emission tomography-CT. Based on these results, she underwent en bloc resection of the tumor, including removal of the involved vessels, and was eventually diagnosed as having a type B2 thymoma permeating into the LBCV and SVC. We present this case as a very rare form of SVCS caused by an invasive thymoma.

WHEN EDEMA ISN'T ANGIOEDEMA: SUPERIOR VENA CAVA SYNDROME AS A CONFOUNDER IN HEREDITARY ANGIOEDEMA

Superior vena cava (SVC) syndrome (SVCS) is any occlusion of the SVC, resulting in venous blood backup. Common causes of SVCS include mediastinal tumors and, less frequently, implanted venous devices. Understanding collateral venous formation in SVCS is crucial for identifying alternative pathways for venous return and alleviating symptoms of venous obstruction. The SVC, formed by the anastomosis of the right and left brachiocephalic veins, drains blood from structures above the diaphragm into the right atrium. Here, we provide a unique postmortem analysis of SVCS and collateral venous formation to support clinical identification and treatment. A 48-year-old cadaver with a limited medical history of metastatic rectal cancer was dissected in an anatomy course. The SVC was observed to be occluded in its entirety. The likely cause of SVCS was mediastinal tumors. Vessel dilation was observed within the azygos system, intercostal, right thoracic-epigastric, inferior epigastric, and internal thoracic veins. Collateral venous formation was found by way of the azygos and hemiazygos veins, which joined inferiorly to form a single vessel draining into the inferior vena cava (IVC), and multiple left intercostal veins formed single communications with the azygos vein. Recognizing this complex anatomy and patterns of the azygos venous system is crucial in understanding alternative blood flow pathways in cases of SVCS. Variations in this system can form critical venous collaterals, bypassing obstructions and relieving venous congestion. Although visualizing these collateral networks on imaging can be challenging, postmortem gross findings offer crucial insights into collateral formations and potential patterns in SVCS presentation. Ultimately, detailed understanding and identification of azygos venous patterns improve patient safety, support accurate diagnosis, and optimize treatment outcomes across a range of medical and surgical disciplines.

Introduction: Different methods have been well addressed in literature in terms of treating superior vena cava (SVC) syndrome; nevertheless, the patency of endovascular treatment has rarely been investigated in patients with SVC syndrome in patients with central venous access. Objectives: The present study was performed to assess the patency rate of endovascular procedure in patients with SVC syndrome caused by intravenous catheterization. Methods: The present case series and longitudinal study was conducted on patients with SVC syndrome in presence of central venous catheter who underwent venoplasty. Computed tomography (CT) venography was performed 1, 6 and 12 months after venoplasty. Facial swelling, facial discomfort, extremity edema, arteriovenous fistula (AVF) dysfunction, impairment in dialysis and SVC stenosis were measured at baseline and 1, 6 and 12 months after venoplasty. Results: Out of 20 investigated patients, 11 (55%) were male. Significantly decreases were observed in the median grades of facial swelling and extremity edema in the follow-up (P<0.001). The decrease in facial discomfort was statistically insignificant (P=0.129), and the median grade of SVC stenosis significantly decreased from 1.5 to zero in the follow-up (P<0.001). A statistically-significant decrease was observed in AVF dysfunction (P=0.007), and impairment in dialysis significantly decreased after the intervention during the follow-up (P<0.001). Conclusion: Findings of the present study revealed the appropriate patency rate of endovascular treatment in patients with SVC syndrome in presence of central venous catheter.

Cavo-Atrial Anastomosis Technique for Partial Anomalous Pulmonary Venous Connection to the Superior Vena Cava—The Warden Procedure

When Catheter Thrombosis Mimics Malignant Cava Thrombosis: The Role of Endovascular Interventions

Superior vena cava (SVC) syndrome is not an uncommon occurrence in patients with malignancy and it is often described as a medical emergency. In majority of the cases, SVC syndrome occurs due to mechanical obstruction of the SVC by extraluminal compression with primary intrathoracic malignancies. However, intraluminal obstruction due to thrombosis can also produce symptoms and signs of SVC syndrome. Clot-related SVC obstruction is mostly associated with indwelling central venous catheter and pacemaker leads, although such thrombosis can occur spontaneously in a background of a hypercoagulable state, e.g., malignancy. Here, an unusual case of sudden onset SVC syndrome has been reported, which on initial radiologic evaluation was found to have a lung nodule without any significant mediastinal mass or adenopathy compressing SVC. Subsequent investigation with Doppler ultrasonography of the neck showed thrombosis in the right internal jugular, right subclavian and right brachiocephalic vein, which was responsible for SVC syndrome. Histopathological evaluation of lung nodule confirmed presence of an adenocarcinoma. Therefore, venous thromboembolism as a paraneoplastic syndrome should be kept in mind while evaluating a case of SVC obstruction in a cancer patient. Management of the underlying disease is of prime importance in such cases and anticoagulation is the mainstay of therapy. Ability to identify paraneoplastic syndrome may have a significant effect on clinical outcome, ranging from early diagnosis to improved quality of life of the patient.

We present a case of an aged male with invasive thymoma that extended into the right atrium and led to superior and inferior vena cava syndrome. The patient initially presented with edema of the face and bilateral lower extremities. Echocardiography revealed a mass within the right atrium. Imaging studies demonstrated an anterior mediastinal tumor that continuously occupied the bilateral brachiocephalic veins, superior vena cava, and right atrium. Pathological diagnosis of the tumor biopsy was highly suspicious of thymoma. Due to the high risk of wide spread of the tumor, treatments including resection of the tumor were impossible. Several days later he died, and an autopsy was performed. The tumor was type B2 thymoma invading bilateral brachiocephalic veins, superior vena cava and right atrium. Multiple tumor emboli within the pulmonary arteries were identified. Direct cause of death was deemed to be tumor strangulation at the tricuspid orifice. In addition to the superior vena cava syndrome, inferior vena cava syndrome including ectasia of the intrahepatic vessels was confirmed along with pericarditis. To our knowledge, this is the first English report of an autopsy case of intracardiac thymoma extension, and a detailed literature review of similar cases is also presented.

3:36 PM Abstract No. 365 Bifurcated Y-stent placement for treatment of superior vena cava syndrome involving both brachiocephalic veins and superior vena cava

In superior vena cava syndrome (SVCS), one or more of the major veins are occlused or deeply stenosed. In these cases. Venous blood from the head, neck, chest and upper limbs regularly reaches brachiocephalic veins and the right atrium through collateral vessels. Several angiographic and echocardiographic studies have reported that in the left brachiocephalic venous stenosis venous blood, instead of flowing toward the superior vena cava and taking the compensation circles to reach the heart, reverses its flow direction through the jugular and then the cerebral veins. In the venous system, flows direction is always centripetal one-way, and a completed flow inversion is possible only in presence of venous stenosis associated with a compensatory circle. Thus, we are here hypothesizing that in SVCS inversion of flows into a jugular vein, already clearly described in the literature, is due to the presence of a compensatory circle that finally connects the superior vena cava to the inferior vena cava. Given that jugular and cerebrospinal veins join with full-channel connections to become a single conduit, we hpothesized that the “new” compensatory circle, deriving from the hemodynamic consequences of SVCS, may include the entire cerebrospinal venous system. This hypothesis is corroborated by the current knowledge on the cerebrospinal venous system: it is a unique, valveless, bidirectional flow circuit that freely communicates with superior and inferior vena cava. In the SVCS, venous blood coming from the head, neck and upper extremities may not descend towards the brachiocephalic vein, as expected from literature, but reverses its flow direction towards the jugular vein and the cerebral spinal venous system, to reach the inferior vena cava.This means that constantly, in the SVCS, part of venous blood coming from the head, neck and upper limbs must cross the brain and the spinal cord to finally reach the right atrium, and that there is a direct contact between the venous blood of the superior vena cava and the cerebrospinal venous system. The continuous passage of venous blood from the superior cava system into the cerebrospinal circulation opens new perspectives in understanding the etiopathogenesis of many neurodegenerative diseases. In vena cava stenosis then, the cerebrospinal circle is subjected to an increase both in pressure and in volume overload, thus creating the possibility that infections, emboli or tumors migrate directly from the peripheral tissues to the brain through the venous route (as already demonstrated in literature). From 2010 to now we have operated for plastic enlargement with patches of saphenous vein, 120 patients with congenital stenosis of the superior vena cava system. These compassionate interventions were undertaken as the “last therapeutic chance” of improving a series of severe and invalidating symptoms, completely non-responsive to each and all clinical practise therapy recommended by updated guidelines, and possibily depending on this blood flow inversion in SVCS. Here we are reporting the angiographic findings of the first two patients with vena cava stenosis. In one we describe the inversion of flow from the site of the obstruction towards the cerebrospinal circle, and in the other we describe the passage of venous blood from peripheral tissues to the cerebrospinal circle.

Results of Superior Vena Cava Reconstruction With Externally Supported Polytetrafluorethylene Vascular Prostheses