Many aneurysms can be fixed with a minimally invasive approach called EVAR, or stent grafting. This surgery involves placing a stent graft (a Dacron or Gore-tex tube supported by metal stents) into the artery to create an internal bypass through the aneurysm. The device is deployed through small incisions in the groin. The surgeon, watching a monitor, manipulates wires and catheters through the arteries. The stent graft is collapsed into a tube, which is inserted into the arteries under fluoroscopy (continuous x-ray). When the device is unsheathed, it unfurls and the radial force of the metal stent fixes it against the wall of the artery to hold it in place. It is fixed to the normal artery above and below the aneurysm. Blood then flows through the stent graft and does not fill the aneurysm. If there is no blood flow through the aneurysm, the aneurysm does not grow and does not rupture. The blood in the aneurysm sac clots, and over time, the outer wall of the aneurysm sac shrinks down around the graft.
This surgery was initially introduced for people who were too sick to consider open aneurysm repair, but currently, we consider this approach for most people with aneurysms, because there is less up-front risk with this surgery. However, treatment is individualized and some people are not good candidates for EVAR. Your doctor will discuss this with you.
After surgery, we monitor the stent graft with imaging (initially CT scan, later ultrasound), to assess the graft, to check the size of the aneurysm sac, and to ensure there is no endoleak. An endoleak is continued flow into the aneurysm. The most common type is caused by small branch vessels that normally arise from the aneurysm and reverse their direction of flow. In most cases, these vessels seal themselves over time. Rarely, they stay open and are associated with increased growth of the aneurysm. In this circumstance, we perform a secondary procedure to block off (embolize) the branches with metal coils.
For most people, EVAR takes about two to three hours. Typically, we use a light general anesthetic. Most people do not require blood transfusion, and most people leave the hospital the day following surgery.
Potential risks of surgery include: heart attack, arrhythmia (abnormal heart rhythm), prolonged intubation, pneumonia, kidney failure, infection, stroke, bleeding, or distal embolization. We have performed over 150 EVAR procedures with a complication rate of less than fve percent.