Superior Vena Caval Obstruction
Superior Vena Caval Syndrome

General Considerations

• Obstruction of flow in the superior vena cava due to:
• Most often due to thoracic malignancy, especially small-cell carcinoma
• Large-cell type of non-Hodgkin lymphoma
• Intravascular thrombosis indwelling catheters
• Mediastinal fibrosis
• Infections such as TB and histoplasmosis
• May produce superior vena caval syndrome
• Obstruction of the SVC results in one or more collateral pathways (60% or more narrowing)
• The azygous venous system, which includes the azygos vein, the hemiazygos vein, and the connecting intercostal veins
• The internal mammary venous system plus tributaries and secondary communications to the superior and inferior epigastric veins
• The long thoracic venous system, with its connections to the femoral veins and vertebral veins, provides the third and fourth collateral routes.

Clinical Findings

• Symptoms depend, in large measure, on how quickly the obstruction develops and the efficiency of the collaterals that are able to form
• Dyspnea is the most common symptom
• Facial swelling
• Cough
• Arm swelling
• Hoarseness
• Stridor

Imaging Findings

• Chest radiography
• Mediastinal or right upper lobe mass
• CT is the study of choice
• Mediastinal mass
• Narrowing or complete obstruction of the SVC
• Collateral flow
• Venography is the most conclusive study

Treatment

• Relieve symptoms with oxygen, diuretics, elevation of the head
• Treat the primary malignancy, if present
• Thrombolysis, if indicated

Prognosis

• Depends on the underlying cause of the obstruction

 Superior vena Caval Obstruction. There is a mediastinal soft tissue mass (white arrows) that is completely obstructing the superior vena cava, the location of which is marked by a red arrow.

Superior Vena Cava Syndrome Treatment and Management. TA Nickloes, AM Kallab, and LO Mack. eMedicine.