The aorta is the largest artery of the human body. It begins from the heart, runs through the chest and abdomen and at the level of the navel splits into two branches, the iliac arteries. The part within the abdomen is called abdominal aorta and supplies blood to all the abdominal organs and to both legs. The normal aorta has a diameter of 1,8 – 2,2 cm. In some patients the aorta is weak and dilates like a balloon. When the size reaches 3cm, an abdominal aortic aneurysm is created.
The main risk is rupture which can be fatal due to internal bleeding. Less commonly peripheral embolization can occur. In most aneurysms there is a significant amount of clot (thrombus) within the aorta. In some cases a piece of clot can travel and block any blood vessel of the abdomen or lower extremity (peripheral embolization).
Abdominal aortic aneurysm is more common in men, older than 60 years. Fortunately, if diagnosed early (before rupture), treatment is simple and effective. Most patients do not have any symptoms. Some may feel a bulging mass in the abdomen. Sudden abdominal or lower back pain or loss of consciousness suggests rupture. On rare occasions patients may feel pain in the abdomen or lower extremity due to peripheral embolization.
The etiology of the aneurysm is unknown. Risk factor include age >60y, 1st degree relative with an aneurysm, high blood pressure and smoking. Diagnosis is confirmed with ultrasound or CT scan. Every male over the age of 60 should have a screening Duplex ultrasound of the abdominal aorta (in case of 1st degree relative with an aneurysm at the age of 50). If repair of the aneurysm is required, patients need to have a CT angiography or an MRI angiography.
The risk of rupture is relative to the diameter. If it is smaller than 5cm, patients should monitor the aneurysm with US or CT every 6-12 months, control their blood pressure and stop smoking.
Repair of the aneurysm is required when it becomes larger than 5cm, when there is a significant increase of diameter or when it becomes symptomatic.
There are two methods of treatment, minimally invasive (endovascular) and open surgical repair.
Percutaneous Aortic Endograft
Percutaneous Aortic Endograft
During the minimally invasive procedure the repairs of the aneurysm is performed from within the vessel (this is why it is called endovascular). Under local anesthesia, the vascular surgeons puncture the femoral arteries of the leg and then place an edograft within the aorta and iliac arteries. The patient is discharged in 1 – 2 days, there is no postoperative pain and recovery is very fast.
Open surgical repair requires general anesthesia and an incision of the entire abdomen. The aorta is replaced with a synthetic graft. Usually after the operation, the patient is transferred to ICU for 1 – 2 days and he is discharged after one week. Full recovery requires 2 – 3 months.
The advantages of the minimally invasive procedure are obvious: no general anesthesia, no abdominal incision, no postoperative pain, early discharge and early recovery. The endovascular repair is performed in most but not all patients.
For both methods there are indications and contradictions.
Endovascular Aneurysm Repair
Branched Aortic Endograft
The results of the endovascular repair are excellent when:
a) It is performed by experienced vascular surgeons in patients suitable for this technique.
b) It is performed in state of the art hybrid operating rooms which combine the safety of the operating room with the superb imaging capabilities of the angiography suite.
c) Last generation endovascular devices are used.
Patients with abdominal aortic aneurysm should consult vascular surgeons with experience in both endovascular and open surgical repairs in order to receive the most appropriate method of treatment.