Customized stents bring endovascular option to more thoracic and abdominal aortic aneurysm patients

April 1, 2021

Melissa Kirkwood, M.D. Surgery

Carlos Timaran, M.D. Surgery

The majority of thoracic and abdominal aortic aneurysms (AAAs) are asymptomatic – a patient has a CT scan or X-ray for an unrelated issue, and the aneurysm is visible on the imaging. Sometimes a primary care physician finds a mass in the lower abdomen during a regular physical exam. An ultrasound screening of patients older than 65 with a history of smoking or family history of aneurysms may also detect the presence of aortic aneurysms. In any case, the patient is referred to our vascular team to verify the diagnosis with an ultrasound and CT scan and to create a treatment plan.

Small AAAs don’t pose a substantial threat. We might recommend monitoring it via imaging every few months to watch for changes in size and check for new weak spots. However, a large AAA raises concerns about a rupture, and we might recommend surgery to repair it.

Ruptured AAA is the 13th-leading cause of death in the U.S., taking approximately 15,000 lives a year.

A potentially lifesaving protocol

Depending on the patient’s overall health and specific condition, our specialists will recommend the appropriate procedure. UT Southwestern’s Advanced Endovascular Aortic Program focuses on treating complex aortic diseases using total endovascular therapies that are minimally invasive. Our team has developed a Physician-Sponsored Investigational Device Exemption (PS-IDE) protocol, which we have used since 2014 to implant fenestrated and/or branched stent-grafts.

Using these devices and minimally invasive therapies, our vascular surgeons can repair most aortic diseases, including complex suprarenal and thoracoabdominal aortic aneurysms and chronic dissections. This approach is appropriate for most patients, especially those who cannot have open surgery, and it provides a faster recovery. Currently, we are the only vascular specialists in the southwestern U.S. with access to all devices for the true total endovascular repair of all aortic diseases.

Whereas in most centers 20% to 30% of patients cannot be offered endovascular repair, more than 90% of aortic aneurysms can be repaired at UT Southwestern using stent-grafts. All approved and investigational devices are currently available through our program.

Currently, we are the only vascular specialists in the southwestern U.S. with access to all devices for the true total endovascular repair of all aortic diseases.

Custom-made stents

Unfortunately, some patients are not eligible for endovascular aneurysm repair (EVAR) because of the location of their aneurysm. Often, it is because the aneurysm is too close to the arteries that branch off to the kidneys, bowel, and liver. In a traditional EVAR, the stent-graft would block blood flow to these organs.

To overcome this issue, UT Southwestern offers fenestrated and branched endovascular aortic repair (F-BEVAR). This approach uses a custom-made stent-graft that is based on a patient’s CT scan and has fenestrations or branches that align with the arteries branching off the aorta to allow blood flow to these organs to continue. To date, we have treated more than 500 patients using F-BEVAR devices.

Our Advanced Aortic Endovascular Program, led by Dr. Timaran, is the only center of excellence in the region with access to these custom-made endovascular aneurysm devices and the expertise to provide them to patients. UT Southwestern earned High Performing recognition from U.S. News & World Report for 2020-21 for abdominal aortic aneurysm repair.

Testing a new device

One downside to F-BEVAR is that the only fenestrated device currently approved by the U.S. Food and Drug Administration (FDA) is a custom-made stent that can take up to six weeks to manufacture. A clinical study being conducted at just 33 medical centers in the U.S., including UT Southwestern, is testing a new fenestrated/branched device.

FDA approval of such a device has the potential to help many more patients with abdominal aortic aneurysm avoid open surgery and get back to their normal lives more quickly. It’s important to remember, however, that some patients may still have to undergo open surgery due to the severity of their condition or the location of their aneurysm.

Along with our expertise in endovascular repair, UT Southwestern is also a center of excellence for open AAA repair. Many locations will not perform these procedures due to limited experience, so they refer their patients to us for the best outcomes. The same is true for our expertise in treating aortic arch aneurysms, which are equally complex.

About the Authors

Melissa Kirkwood, M.D., an Associate Professor of Surgery, is Chief of the Division of Vascular Surgery, Medical Director of the Clinical Heart and Vascular Center, and Director of the Vascular Lab at UT Southwestern. She specializes in all aspects of vascular surgery: peripheral artery disease and limb salvage with both advanced endovascular and open techniques, carotid artery disease, and open and endovascular aortic surgery.

Carlos Timaran, M.D., a Professor of Surgery and Chief of Endovascular Surgery at UT Southwestern, is an internationally recognized expert in advanced endovascular techniques. He is one of only a few surgeons in the U.S. who perform aneurysm repair using customized fenestrated endovascular grafts. Dr. Timaran has authored more than 80 peer-reviewed abstracts and over 65 articles in peer-reviewed journals and has given more than 200 lectures and presentations around the world.