Thoracic Endovascular Aortic Repair (TEVAR)
is a minimally invasive operation used to treat some diseases of the thoracic aorta. This surgery is performed without opening up the chest cavity. TEVAR is suitable for patients with descending aortic aneurysm which is larger than 5 cm and rapidly enlarging aneurysms. This procedure has been used since 2003 and as new screening technology and devices become available, patients who were unsuitable for open heart surgery or previously for TEVAR are now considered suitable. Prior to undergoing TEVAR, patients are extensively “worked up”, meaning they undergo numerous tests prior to being deemed a suitable candidate. The anatomy of the aneurysm and the surrounding structures are taken into consideration when assessing the patient for suitability for TEVAR. Advancements within the medical field and the availability of different grafts/instruments will help improve outcomes even further and allow for more patients to be candidates for the minimally invasive procedure. Prior to TEVAR, the only option for aortic aneurysm repair was open surgery.
The procedure is carried out in the cardiac surgery operating room under x-ray fluoroscopy guidance. The procedure is usually performed with the patient fully asleep (general anaesthetic). The access to the aorta is gained by a poke in the femoral arteries in the groin. Guidewires and catheter are inserted into the groin and passed through the arteries up to the aorta.
Illustration of stent graft being deployed to treat a descending thoracic aneurysm. Access is obtained via a small groin incision.
Throughout the procedure, x-ray and ultrasound images help the surgeon guide the devices to the appropriate site. The graft can be secured in place using a “ballooning” technique., where the surgeon expands a small balloon inside the ends of the grafts to ensure it is firmly adhered to the healthy aortic wall (landing site) and then the catheter is pulled back leaving the endograft in place and the diseased section of the aorta is contained. Once the graft is placed and secured, the blood flow is established through this structure and not into the surrounding aneurysm sac, thus taking off the pressure of the aneurysm sac.