Thoracic Aortic Stenting
Thoracic Aortic Endovascular Stent Grafting (TEVAR)
When an aortic aneurysm reaches a dangerous size, it may be possible to repair it with minimally invasive techniques called Thoracic Endovascular Aneurysm Repair (TEVAR). In some cases thoracic aortic dissection can also be treated with TEVAR.
TEVAR basically means repairing the aneurysm from within and is performed with a small cut in the groin. TEVAR reduces the risk of aneurysm repair provided the patient and the aneurysm are suitable. Unfortunately, not all patients are suitable, and attempting TEVAR in these cases may be more dangerous.
There is usually some pre-operative medical workup required, as well as specialised CT scans and possibly an angiogram. The procedure requires careful planning in co-operation with the company who manufacture the stent grafts which are placed during the repair. Depending on the complexity of the case, this may take 6-8 weeks to plan and manufacture to ensure an exact fit to your aneurysm. The device is usually in on or two parts.
The operation is performed under general anaesthetic with intra-operative monitoring for maximum safety. These may include an arterial pressure monitor in the artery at the wrist, a central line venous catheter and a urinary catheter. These are placed after anaesthetic for maximum comfort. In addition, a spinal fluid draining catheter may be inserted (see below).
The operation is usually performed through an incision of about 5cm in a groin. Through this incision, the femoral artery is carefully dissected out. A percutaneous sheath is placed in the other groin’s femoral artery. A small angiogram catheter is placed and imaging of the aorta and the aneurysm is performed. Blood thinner is given. The stent graft is introduced, positioned, checked and deployed in the aorta, achieving a seal above and below the aneurysm. This excluding the aneurysm from the blood pressure and rendering it safe. The artery in the groin is then repaired and the wound carefully closed in layers.
You may need to be treated in intensive care after the TEVAR repair. Usually patients are mobile after a few days and discharged in 5 days or less.
There are several complications which can occur during and after TEVAR aneurysm repair including bleeding, bowel dysfunction, limb dysfunction, renal dysfunction, heart strain and heart attack, lung problems including pneumonia and others. In worst cases, death can occur, though 98% patients survive. A complication specific to procedures on the thoracic aorta is paraplegia which can occur in up to 11% of cases. The incidence of paraplegia is usually less after TEVAR compared with open surgery. Several techniques are used to reduce the incidence of paraplegia and one of these is to drain some spinal fluid from the back via a spinal drain inserted at the time of surgery.