The superior vena cava (SVC) is the second largest vein in your body, carrying deoxygenated blood from the upper half of your body to the right atrium, which is one of the four chambers in your heart. SVC obstruction occurs when the vein becomes narrowed or blocked. The obstruction may be a chronic condition, meaning it lasts for a long time, or it may be acute, meaning the condition starts suddenly and lasts for a short time.
In most cases, the cause of the obstruction is cancer, particularly lung cancer, although not all of the possible causes are cancerous.
The main symptom is shortness of breath. Other symptoms include a cough, headaches, swelling of the face, neck or arms, and swelling of veins in the neck, chest or arms.
A doctor can diagnose the condition using imaging techniques, such as contrast-enhanced CT, MRI or a technique called a digital subtraction angiography.
If the obstruction in the vein is caused by cancer, it is usually treated with radiation therapy and chemotherapy. However, it may take several weeks for the patient to respond to these treatments.
SVC stenting, in which an interventional radiologist places a metal stent into the narrowed or blocked vein to hold it open, is a minimally invasive option which can be carried out as a stand-alone procedure or in addition to other treatments. The interventional radiologist will use fluoroscopy for guidance while inserting a catheter into a large vein, leading it to the affected area, and placing a stent there to provide relief. In most cases, symptoms will clear up quickly following the stent placement, usually within 24 to 48 hours.