The superior vena cava is an essential vein that returns used blood from the upper half of the body to the heart. If the vein becomes blocked or restricted due to a cancerous tumor, infection, blood clot or another anomaly, the result is called superior vena cava syndrome. Obstructions can cause symptoms ranging from dizziness and headaches to severe facial and throat swelling. Treatment of superior vena cava syndrome typically focuses on the cause of the blockage, and may entail chemotherapy treatment, steroid injections, antibiotics or surgery. When the condition is detected and treated early, most patients experience full recovery.
Malignant tumors in the lungs, breasts, thyroid and lymph nodes in the chest are the leading causes of superior vena cava syndrome. The vein is not well protected and can easily become compressed by a growing tumor. Blood clots, goiters and heart aneurysms can also restrict proper blood flow into the heart. In addition, untreated bacterial and viral infections such as tuberculosis and syphilis can occasionally lead to inflammation and blockage in the superior vena cava.
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The disease tends to develop gradually as tumors or other conditions progress, though acute cases of superior vena cava syndrome may result from blood clotting. In the early stages of the disease, patients may experience dizzy spells, lightheadedness, frequent headaches and minor vision problems. Redness in the cheeks, nose, hands and arms occurs as blood flow is further restricted. Eventually, the neck and face become swollen and start to turn blue. Throat swelling can lead to serious breathing problems that may result in unconsciousness and brain damage if not relieved immediately.
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A physician who suspects progressive superior vena cava syndrome can conduct a physical examination of the patient's throat and face and check for signs of abnormal blood pressure. A chest x-ray and computerized axial tomography (CAT)scan can reveal the cause and severity of the obstruction. The physician will usually administer steroids or diuretics to relieve immediate swelling symptoms, and then determine the best course of treatment for the underlying cause.
Chemotherapy or radiation treatments are typically performed to eradicate cancerous tumors in the chest or lungs. Anticoagulant medications can relieve blood clots, and bacterial infections are treated with oral or intravenous antibiotics. Surgery is rarely performed due to the vulnerability of the heart and surrounding structures. The prognosis for patients with noncancerous conditions is very good, and most people recover from their symptoms in less than one month. Cancer patients may need to receive ongoing treatment and monitoring sessions to make sure that cancer does not spread to other parts of the body.