Endoleaks

Endovascular aneurysm repair (EVAR) places a fabric-covered metal tube, called a stent-graft, inside an aortic aneurysm. Blood flows through the tube, and the old aneurysm around it, called the sac, is left without pressure. Over time the sac usually shrinks.

An endoleak means blood is still getting into the sac, outside the stent-graft. The word does not mean blood is leaking out of your body or into your belly. It is a leak into the space that the repair was meant to seal off. If enough pressure builds up in the sac, the aneurysm can keep growing and, rarely, burst. That is why every EVAR is followed by lifelong scans.

Endoleaks are common. Roughly 1 in 4 people who have EVAR will have one at some point, most often in the first year. Many need no treatment at all.

Doctors sort endoleaks into five types based on where the blood is coming from. The type tells us how urgent it is.

What we see

Most endoleaks cause no symptoms. They are found on the routine scans after EVAR, which is why keeping those appointments matters so much. You cannot feel whether your repair is working.

After EVAR you will have a scan at about 1 month, then usually at 12 months, and then every year if everything looks stable. The scan compares the size of the sac with earlier scans and looks for contrast outside the stent-graft.

The number that matters most is the sac size. A sac that is shrinking or stable is reassuring, even if a small type II leak is present. A sac that has grown by 5 mm or more usually means it is time to treat.

The goal is to stop blood from pressurizing the sac. The right treatment depends on the type of leak.

Embolization is the most common treatment for a type II endoleak. Embolization means blocking a blood vessel on purpose. We fill the leaking space, and the small arteries feeding it, with tiny soft metal coils and a liquid plug or glue. There are two main ways to reach it:

When I read a scan after EVAR, the first thing I compare is the sac size against every earlier scan. A small type II leak with a sac that is shrinking does not worry me, and I tell patients that plainly. If the sac is growing, I study the delayed images carefully to find exactly which small arteries are feeding it and plan the most direct route in, because the aim is to seal the whole channel, not just one branch.

Fabio Komlos, MD, interventional radiologist · About Dr. Fabio Komlos

1. 1
   Preparation

   You do not eat for about 6 hours beforehand, and we give you instructions about blood thinners. An IV is placed and you receive moderate sedation or, sometimes, general anesthesia.

2. 2
   Reaching the leak

   We numb the skin and reach the sac either through a pinhole in the groin artery or with a thin needle through the back, guided by X-ray or CT.

3. 3
   Sealing the leak

   We place coils and a liquid embolic agent into the sac and the feeding branches until contrast no longer flows in. This usually takes 1 to 3 hours.

4. 4
   Recovery

   The catheter or needle is removed and the site is bandaged. You rest for a few hours, and some people stay overnight for observation.

1. First day
   Rest at home with an adult to drive you. No driving, alcohol or important decisions for 24 hours after sedation. Mild back or groin soreness is common.
2. First few days
   Some people have a low fever or aching for a few days as the sac clots. Over-the-counter pain relievers usually help. Avoid heavy lifting for about a week.
3. About 1 month
   A follow-up scan checks that the leak has sealed and the sac is stable.
4. Every year
   Lifelong scans continue, because a new leak can appear later.

Embolization stops sac growth in many patients, but type II endoleaks can come back through other small branches, and some people need a second treatment. Type I and III leaks are usually fixed well with extra stent-graft pieces. If less invasive fixes do not work, open surgery is an option, done by a vascular surgeon.