SVC obstruction
Superior vena cava obstruction; Superior vena cava syndrome
SVC obstruction is a narrowing or blockage of the superior vena cava, which is the second largest vein in the human body. The superior vena cava moves blood from the upper half of the body to the heart.
Causes
Superior vena cava (SVC) obstruction is a relatively rare condition.
It is most often caused by cancer or a tumor in the mediastinum (the area of the chest under the breastbone and between the lungs).
The types of cancer that can lead to this condition include:
- Breast cancer
- Lymphoma
-
Metastatic lung cancer
(lung cancer that spreads)
Metastatic lung cancer
Small cell lung cancer (SCLC) is a fast-growing type of lung cancer. It spreads much more quickly than non-small cell lung cancer. There are two typ...
- Testicular cancer
- Thyroid cancer
- Thymus tumor
Superior vena cava obstruction can also be caused by noncancerous conditions that cause scarring. These conditions include:
-
Histoplasmosis
(a type of fungal infection)
Histoplasmosis
Histoplasmosis is an infection that occurs from breathing in the spores of the fungus Histoplasma capsulatum.
-
Inflammation of a vein (
thrombophlebitis
)
Thrombophlebitis
Thrombophlebitis is swelling (inflammation) of a vein. A blood clot (thrombus) in the vein can cause this swelling.
-
Lung infections (such as
tuberculosis
)
Tuberculosis
Pulmonary tuberculosis (TB) is a contagious bacterial infection that involves the lungs. It may spread to other organs.
Other causes of superior vena cava obstruction include:
-
Aortic aneurysm
(a widening of the artery that leaves the heart)
Aortic aneurysm
The aorta is the main blood vessel that supplies blood to the abdomen, pelvis, and legs. An abdominal aortic aneurysm occurs when an area of the aor...
- Blood clots in the superior vena cava
-
Constrictive pericarditis
(tightening of the thin lining of the heart)
Constrictive pericarditis
Constrictive pericarditis is long-term (chronic) inflammation of the sac-like covering of the heart (the pericardium) with thickening and scarring. ...
- Effects of radiation therapy for certain medical conditions
- Enlargement of the thyroid gland (goiter)
Catheters placed in the large veins of the upper arm and neck may cause blood clots in the superior vena cava.
Symptoms
Symptoms occur when something blocks the blood flowing back to the heart. They may begin suddenly or gradually, and may worsen when you bend over or lie down.
Early signs include:
- Swelling around the eye
- Swelling of the face
- Swelling of the whites of the eyes
The swelling will most likely be worse in the early morning hours and go away by mid-morning.
The most common symptoms are shortness of breath (dyspnea) and swelling of the face, neck, trunk, and arms.
Shortness of breath
Breathing difficulty may involve:Difficult breathingUncomfortable breathingFeeling like you are not getting enough air
Other possible symptoms include:
-
Decreased alertness
Decreased alertness
Decreased alertness is a state of reduced awareness. A coma is a state of decreased alertness from which a person cannot be awakened. A long-term co...
-
Dizziness
Dizziness
Dizziness is a term that is often used to describe 2 different symptoms: lightheadedness and vertigo. Lightheadedness is a feeling that you might fai...
- Fainting
- Headache
- Reddish face or cheeks
- Reddish palms
- Reddish mucus membranes (inside the nose, mouth, and other places)
- Redness changing to blueness later
- Sensation of head or ear "fullness"
- Vision changes
Exams and Tests
An examination may show enlarged veins of the face, neck, and upper chest. Blood pressure is often high in the arms and low in the legs.
A bronchoscopy (a lighted tube placed through the mouth into the windpipe and lungs) may be performed if lung cancer is suspected.
Bronchoscopy
Bronchoscopy is a test to view the airways and diagnose lung disease. It may also be used during the treatment of some lung conditions.
Lung cancer
Small cell lung cancer (SCLC) is a fast-growing type of lung cancer. It spreads much more quickly than non-small cell lung cancer. There are two typ...
Blockage of the SVC may be visible on:
-
Chest x-ray
Chest x-ray
A chest x-ray is an x-ray of the chest, lungs, heart, large arteries, ribs, and diaphragm.
-
CT scan of the chest
or
MRI of chest
CT scan of the chest
A chest CT (computed tomography) scan is an imaging method that uses x-rays to create cross-sectional pictures of the chest and upper abdomen....
MRI of chest
A chest MRI (magnetic resonance imaging) scan is an imaging test that uses powerful magnetic fields and radio waves to create pictures of the chest (...
-
Coronary angiography
(a heart blood vessel study)
Coronary angiography
Coronary angiography is a procedure that uses a special dye (contrast material) and x-rays to see how blood flows through the arteries in your heart....
-
Doppler ultrasound
(sound wave test of the blood vessels)
Doppler ultrasound
This test uses ultrasound to look at the blood flow in the large arteries and veins in the arms and legs.
-
Radionuclide ventriculography
(nuclear study of heart motion)
Radionuclide ventriculography
Nuclear ventriculography is a test that uses radioactive materials called tracers to show the heart chambers. The procedure is noninvasive. The ins...
This disease may also affect the results of the following tests:
-
Abdominal MRI
or CT scan
Abdominal MRI
An abdominal magnetic resonance imaging scan is an imaging test that uses powerful magnets and radio waves. The waves create pictures of the inside ...
-
Liver scan
Liver scan
A liver scan uses a radioactive material to check how well the liver or spleen is working and to assess masses in the liver.
Treatment
The goal of treatment is to relieve the blockage.
Diuretics (water pills) or steroids may be used to temporarily relieve swelling .
Swelling
Swelling is the enlargement of organs, skin, or other body parts. It is caused by a buildup of fluid in the tissues. The extra fluid can lead to a ...
Other treatment options may include radiation or chemotherapy to shrink the tumor, or surgery to remove the tumors. Surgery to bypass the obstruction is rarely performed. Placement of a stent to open up the SVC is available at some medical centers.
Chemotherapy
The term chemotherapy is used to describe cancer-killing drugs. Chemotherapy may be used to:Cure the cancerShrink the cancerPrevent the cancer from ...
Stent
A stent is a tiny tube placed into a hollow structure in your body. This structure can be an artery, a blood vessel, or something such as the tube t...
Outlook (Prognosis)
The outcome varies, depending on the cause and the amount of blockage.
SVC syndrome caused by a tumor is a sign that the tumor has spread, and it indicates a poorer long-term outlook.
Possible Complications
The throat could become blocked, which can block the airways.
Increased pressure may develop in the brain, leading to changed levels of consciousness, nausea, vomiting, or vision changes.
When to Contact a Medical Professional
Call your health care provider if you develop symptoms of SVC obstruction. Complications are serious and can sometimes be fatal.
Prevention
Prompt treatment of other medical disorders may reduce the risk of developing SVC obstruction.
References
Rice TW, Rodriguez MR, Light RW. The superior vena cava syndrome: clinical characteristics and evolving etiology. Medicine (Baltimore) . 2006;85;1:37-42. PMID: 16523051 www.ncbi.nlm.nih.gov/pubmed/16523051 .
Ugras-Rey SS. Selected oncologic emergencies. In: Marx JA, Hockberger RS, Walls RM, et al, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice . 8th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 123.
Wilson LD, Detterbeck FC, Yahalom J. Superior vena cava syndrome with malignant causes. N Engl J Med . 2007;356:1862-9. PMID: 17476012 www.ncbi.nlm.nih.gov/pubmed/17476012 .
-
Heart, section through the middle - illustration
The interior of the heart is composed of valves, chambers, and associated vessels.
Heart, section through the middle
illustration
Review Date: 1/13/2015
Reviewed By: Jacob L. Heller, MD, MHA, Emergency Medicine, Virginia Mason Medical Center, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.