Superior vena cava obstruction (SVCO)

Key points about superior vena cava obstruction

  • Superior vena cava obstruction (SVCO) occurs when a major vein in your body called the superior vena cava is blocked.
  • The most common cause is lung cancer. 
  • Common symptoms include breathlessness, change in vision, dizziness, headache, cough, chest pain, face and arm swelling, visible blue veins on your chest and neck, and difficulty swallowing.
  • SVCO is a medical emergency, so see your doctor or call an ambulance immediately if you have any of these symptoms. 
  • Treatment aims to reduce compression of the superior vena cava and relieve symptoms. Sometimes you may need a procedure called stenting to relieve the obstruction.
  • There is support available to talk about what it is like to experience SVCO.
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The superior vena cava is a major vein in your body that carries blood from your head, neck, upper chest and arms to your heart. SVCO can occur due to:

  • compression of the vein by cancers or nearby swollen lymph nodes
  • blood clots in the vein
  • cancers spreading from other parts of your body to the vein.

The most common cause of SVCO is lung cancer. It can either compress directly on the superior vena cava or spread to nearby lymph nodes, causing them to swell and press on the vein. Other types of cancers that can spread to nearby lymph nodes include:

SVCO can also occur if there are blood clots forming in the superior vena cava, blocking the blood flow. This can occur as a side effect of cancer itself, or after a small tube (central line) is inserted into the vein to give medications such as chemotherapy

Symptoms can develop quickly over a few days or gradually as a long-term problem. Common symptoms of SVCO include:

  • breathlessness
  • changes in vision
  • dizziness
  • headache that worsens when bending forward or lying down 
  • cough
  • chest pain
  • visible blue veins on your chest or neck
  • face, neck or arms swelling
  • difficulty swallowing.

SVCO is a medical emergency. If you have any of the symptoms above, see your doctor or call an ambulance immediately. 

Your doctor will take a history and do a physical examination and request some tests based on your symptoms. This usually involves urgent scanning of your chest such as a chest X-ray, MRI or CT scan.

Your doctor will discuss with you the best treatment options beforehand, depending on the type of cancer you have. Before treatment is started, your doctor may ask you about your wishes or whether you have any advance care plan. You may also be admitted to hospital to receive treatment and be referred to a palliative care specialist.

Treatment aims to reduce compression of superior vena cava and relieve symptoms. Your doctor will consider giving you the following medications:

Sometimes, you may need a procedure called stenting to relieve the obstruction. The procedure involves putting in a small tube in your vein to keep the blood flowing. It is usually done with local anesthetic. You may also need radiotherapy or radiation treatment to destroy cancer cells around the area of compression. 

It can be scary to have SVCO as the condition can cause difficulty breathing. Talk through your feelings with your family members or health professionals taking care of you.

Below are some support services and information for people affected by cancer and their family/whānau:

Emotions and cancer(external link) Cancer Society of NZ
How we can help(external link) Cancer Society of NZ
NZ cancer services – find a hospital/service near you(external link) Healthpoint, NZ
More cancer support groups

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Credits: Healthify editorial team. Healthify is brought to you by Health Navigator Charitable Trust.

Reviewed by: Jarna Standen, Registered Nurse, Mercy Hospice, Auckland

Last reviewed:

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