Superior Vena Cava Syndrome.

Superior vena cava syndrome (SVCS) or superior vena cava obstruction (SVCO) is caused by gradual compression/obstruction of the superior vena cava vein by disease, growth or malignancies of any of the structures which surround it. However presently in 90% of the cases, this syndrome is associated with malignancy and in 80% of these cases, bronchogenic carcinoma is the cause.

Occurrence of symptoms is gradual and therefore it is found that the diagnosis is often delayed till symptoms become severe due to significant obstruction. The SVC is particularly susceptible to compression because it is thin-walled, has low pressure of blood flowing through it  and rigid structures surrounding it.

Signs and Symptoms.

Usually the following symptoms are seen:

• Shortness of breadth or dyspnea.
• Chest pain
• Swelling of face or arm.
• Distended veins in the neck, upper part of chest and arms.
• Bluish tinge to the skin of face and neck.
• Cough.
• Hoarseness of voice.
• Stuffed nose.
• Headache.
• Dizziness and giddiness.
• Edema of the face and/or upper extremities.

Causes.

Previously, before modern day antibiotics, infections commonly caused superior vena cava syndrome. These infections include tuberculosis, syphilis and fungal infections.

Today with the advent of new antibiotics, these infections are cured and 80% to 90% of the cases are due to malignancy, the most common being bronchogenic carcinoma.

15% of the cases are caused by lymphoma.

Other causes include thrombosis due to catheter related procedures such as dialysis and pacemaker leads.

Picture showing superior vena cava syndrome.

Click on image to enlarge.

Diagnosis of Superior Vena Cava Syndrome.

Besides the signs and symptoms that help to arrive at a diagnosis, certain investigations are required to confirm the diagnosis and cause of the syndrome.

• Chest X-ray may show mediastinal widening and even the primary cause of SVCS.
• CT scan should be contrast enhanced and should be of the neck, chest, abdomen and pelvis to detect the cause and its extent.
• Ultrasound
• MRI
• Bronchoscopy and mediastinoscopy for transbronchial aspiration.
• Venography may be necessary also wherein a dye is injected and the veins are x-rayed.

Treatment.

Treatment typically aims at treating the underlying cause. The usual care is given to breathing, clearing of airway and circulation.

• Malignancies are treated with radiation and chemotherapy.
• Infections are treated with the appropriate antibiotics.
• Thrombosis is treated with clot-busting drugs (thrombolytic drugs), blood thinners, angioplasty and in some cases surgery may be required.

Prognosis.

The outlook of this disease for patients depends on the underlying cause of this syndrome. Symptoms due to a malignant cause are usually relieved within one month. However most cases due to malignancy succumb within two to two and half years even with treatment. Without treatment, patients with SVCS due to malignancy die within one month.

Prevalence by Age.

Superior vena cava syndrome due to malignancy usually occurs in elderly people and where the cause is not malignant including lymphoma, the younger age group is affected. The average age of onset is 54 years.

Related posts:

1. Superior Vena Cava.
2. Inferior Vena Cava.
3. Parts of the Heart.
4. Fetal Alcohol Syndrome.
5. Carpal Tunnel Syndrome.
6. Right Atrium of the Heart.
7. Right Heart.