Endovascular Aneurysm Repair (EVAR)

Endovascular Aneurysm Repair (EVAR) is a minimally invasive surgical procedure to treat an aneurysm in the aorta, the main blood vessel that carries oxygen-rich blood away from the heart to the various parts of the body. The procedure involves inserting a stent-graft (a metal mesh tube covered with fabric) through an artery in the groin under X-ray guidance and advancing it up into the site of the aneurysm in the aorta to provide reinforcement and help prevent the aneurysm from bursting.

EVAR is often performed to improve blood flow to an area of the aorta that has been damaged or obstructed, following an injury, disease, or other condition.

Disease Overview

Aortic aneurysm is a condition characterized by an abnormal ballooning or bulging of a section of the aorta due to weakness in the wall of the blood vessel. An aneurysm can develop anywhere along the aorta:

• An aneurysm that occurs in the segment of the aorta that is found in the chest is called a thoracic aortic aneurysm.
• An aneurysm that occurs in the segment of the aorta that passes through the abdomen is called an abdominal aortic aneurysm. This is the more common type of aortic aneurysm.

Most patients with an aortic aneurysm do not have any symptoms. Usually, when the aneurysm enlarges it may cause chest or back pain, palpitations, fatigue, dizziness, or shortness of breath.

Indications

Your surgeon may recommend an endovascular aneurysm repair in the following instances:

• You are not a candidate for traditional open repair
• The aneurysm or bulge is increasing or growing in size (5 cm or more)
• To prevent the risk of rupture of the aneurysm, which can cause death
• There is damage to the aorta from injury or trauma
• There is a focal penetrating ulcer in the aorta
• There is aortic stenosis or a narrowing of the aorta
• There is aortic dissection or separation of the 3 layers of the aorta
• Conservative treatment measures have failed to relieve the symptoms of the aortic aneurysm

Preparation

Preoperative preparation for endovascular aneurysm repair may involve the following:

• A thorough history and physical examination
• Several tests such as electrocardiogram (ECG), stress testing, and other scans
• Informing your doctor of any medications or supplements you are taking
• Informing your doctor of any allergies to medications, anesthesia, or latex
• Refraining from blood thinners, aspirin, or NSAIDs
• Refraining from solids or liquids at least 8 hours prior to the procedure

Surgical procedure

During the EVAR procedure, an endovascular stent is placed inside the aorta to protect the aneurysm from rupturing. In general, the minimally invasive endovascular aneurysm repair will involve the following steps:

• You will be administered general or local anesthesia by your anesthesiologist.
• You will lie on your back on the operating table and the groin area is shaved and cleaned with an antiseptic solution.
• A small surgical cut is made in the groin area to access the blood vessel (femoral artery).
• Under fluoroscopic (live X-ray) guidance, a small catheter (thin tube) is inserted into the femoral artery and advanced to the site of the aortic aneurysm.
• A guide wire and an expandable stent-graft is then passed through the catheter into the affected area of the aorta.
• A contrast medium (dye) is injected into the aorta so that the affected area is clearly visible for precise placement of the stent-graft.
• The stent graft is delivered in a collapsed state through the catheter to the treatment area and expanded to fit against the walls of the aorta on either side of the aneurysm.
• The graft reinforces the weakened section of the aorta to prevent the aneurysm from rupturing.
• Consequently, the blood flows through the graft, avoiding the aneurysm that normally shrinks over time as the blood supply is diverted away from the aneurysm.
• Finally, your physician will withdraw the guidewire and catheter, and the groin incision is sutured and closed with a small bandage.
• After the procedure, X-rays are taken to ensure the correct placement of the stent and to check for any leakage of blood.

Postoperative care

Following the procedure, you will be taken to the recovery room where you will be closely monitored. You may need to stay in the hospital for 2 to 3 days. You will be given blood thinning medications to prevent blood clot formation. Pain medications are also given to ease any discomfort. Your doctor may recommend special stockings for your legs to inhibit blood clot formation. You can resume all your normal activities within a month, but you should refrain from strenuous activities, lifting heavy weights, and driving for at least 4 to 6 weeks or until your physician approves. Follow-up visits may be ordered, during which a CT scan may be necessary to ensure optimal functioning of the graft.

Benefits

Some of the benefits of endovascular aneurysm repair over traditional open surgery include:

• Shorter hospital stay
• Faster recovery
• Minimal muscle trauma
• Smaller to no visible scar
• Less bleeding
• Decreased risk of infection
• Less postoperative pain
• Quicker return to normal activities

Risks and Complications

Endovascular aneurysm repair is a relatively safe procedure; however, as with any surgery, some risks and complications may occur, such as the following:

• Infection
• Bleeding
• Blood clots or deep vein thrombosis (DVT)
• Damage to nearby tissues or organs
• Stent migration
• Endoleak (leakage of blood from the graft)
• Injury to kidneys
• Heart attack
• Stroke
• Tissue necrosis (death of tissue)

Summary

Endovascular aneurysm repair is recommended as a preventative treatment to avert aneurysm rupture and death. It is a less invasive procedure when compared to an open surgery repair and helps to avoid rupture of the aneurysm in over 99% of patients. After the repair of the aneurysm, patients are advised certain lifestyle changes such as abstinence from smoking, avoiding lifting heavy objects, controlling blood pressure and blood cholesterol levels, and doing gentle exercise such as cycling and walking to improve their condition and prevent the recurrence of an aneurysm.