by EBSCO Medical Review Board
(Endovascular Coiling of Cerebral Aneurysm)


Endovascular embolization is a procedure that blocks blood flow in a specific area. In this case, it blocks blood flow through a weakened artery in the brain.

Reasons for Procedure

This procedure is done to manage an aneurysm. This is a weakened spot in the wall of the artery. It may cause bleeding or burst. The embolization will decrease the risk of this from happening.

Possible Complications

Problems are rare, but all procedures have some risk. Your doctor will review some problems that may happen, such as:

  • Infection
  • Allergic reactions to anesthesia
  • Stroke due to a blood clot
  • Seizures
  • The aneurysm is punctured and bursts
  • The aneurysm is not fully closed and problems return

Before your procedure, talk to your doctor about ways to manage factors that may increase your risk of problems, such as:

What to Expect

Prior to Procedure

The doctor will use previous tests to plan the surgery. Follow these steps leading up to the procedure:

  • Arrange for a ride to and from the care center. Also, arrange for someone to help you at home.
  • Talk to your doctor about your medicines. You may be asked to stop taking some up to one week before surgery.
  • Tell your doctor about any allergies you may have. This includes any allergy to contrast dye.
  • Tell your doctor if you may be pregnant.
  • Do not eat or drink after midnight the night before surgery.

A ruptured aneurysm is an emergency. The procedure may need to be done right away.


Your doctor will talk to you about options including:

  • Moderate sedation—You will be but sleepy and will not feel pain.
  • General anesthesia—You will be asleep.

Description of the Procedure

An incision will be made in your groin. A hollow needle will be inserted into your artery. A long tube will be passed through the needle. An x-ray machine will show the doctor where the tube is in your body.

The tube will be guided through the artery, past the heart, and into the brain. A dye will highlight the blood vessels and blood flow. A second tube will be placed in the first one and guided to the aneurysm. Coils will be guided through the tube and inserted into the area. A blockage will naturally form over the coil. It will stop blood flow to the weak artery. Some aneurysms may need a metal tube called a stent to hold the coils in place.

The doctor will check to make sure blood is no longer flowing into the aneurysm. The tube will be taken out. A seal may be placed over the puncture site to close it. A bandage will be put on the incision.

Immediately After Procedure

You will need to lie flat for 2 to 6 hours.

How Long Will It Take?

It will take 2 to 4 hours.

How Much Will It Hurt?

Anesthesia will prevent pain during the procedure. You may have some discomfort when the tube is first inserted. The area will be sore for a few days after the procedure.

Average Hospital Stay

A person with an unruptured aneurysm will stay in the hospital overnight. A person with an aneurysm that ruptured will need to stay longer.

Post-procedure Care

At the Care Center

The staff will check on your progress until the anesthesia wears off.

During your stay, the hospital staff will take steps to reduce your chance of infection such as:

  • Wash their hands before contact.
  • Wear gloves or masks as needed.
  • Keep the incision covered.

There are also steps you can take to reduce your chances of infection such as:

  • Wash your hands often. Remind visitors and your care team to do the same.
  • Remind your care team to wear gloves or masks as needed.
  • Do not allow others to touch your wound.
At Home

Strenuous activities will need to be limited for two weeks.

Call Your Doctor If Any of the Following Occurs

Call your doctor if any of these occur:

  • Signs of infection, such as fever and chills
  • Redness, swelling, pain, bleeding, or discharge from the incision
  • Pain that you cannot control with the medicine you were given
  • Pain, swelling, cramping, or loss of feeling in your legs
  • Chest pain
  • Lightheadedness

If you think you have an emergency, call for emergency medical services right away.


American Heart Association 

National Institute of Neurological Disorders and Stroke 


Health Canada 

Heart and Stroke Foundation of Canada 


Brott TG, Halperin JL, et al. 2011 ASA/ACCF/AHA/AANN/AANS/ACR/ASNR/CNS/SAIP/SCAI/SIR/SNIS/SVM/SVS guideline on the management of patients with extracranial carotid and vertebral artery disease: executive summary. Stroke. 2011 Aug;42(8):e420-63 full-text, correction can be found in Stroke 2011 Aug;42(8):e541.

Carotid angioplasty and stenting. Johns Hopkins Medicine website. Available at: Accessed July 19, 2020.

Carotid artery disease: carotid stenting. Cleveland Clinic website. Available at: Accessed July 19, 2020.

Carotid artery stenting. British Society of Interventional Radiology website. Available at: Accessed July 19, 2020.

Carotid artery stenosis repair. EBSCO DynaMed website. Available at: Accessed July 19, 2020.

Carotid stenting. UCSF Department of Surgery website. Available at: Accessed July 19, 2020.

Endovascular angioplasty with stenting (CAS). Johns Hopkins Medicine website. Available at: Accessed July 19, 2020.

Revision Information

  • Reviewer: EBSCO Medical Review Board Rimas Lukas, MD
  • Review Date: 07/2020
  • Update Date: 07/19/2020