An abdominal aortic aneurysm (AAA) occurs when the aorta enlarges abnormally due to damage or weakness in the vessel wall. It is a potentially fatal condition--with a 90 percent fatality rate--and is the third-leading cause of death. Because of its asymptomatic nature, the condition is usually only recognized after a rupture. If the aneurysm is identified before it ruptures, a surgical intervention takes place, usually only after the AAA has grown to an unsafe size--approximately 5.5 cm. Two options for surgical treatment are available for abdominal aortic aneurysms: the open abdominal approach and the endovascular approach.
Open Repair Procedure
The open abdominal aortic aneurysm repair procedure is the more conventional approach to repairing an AAA. In this procedure, a thoracic surgeon opens the abdominal cavity, displaces the intestines and exposes the aorta. Clamping of the aorta takes place to stop blood flow through the organ and the weakened region in the aorta is replaced with a Dacron graft, in the shape and size of a healthy aorta. While the procedure is highly invasive, this route boasts success rates of greater than 90 percent, according to Vascular Web, a website provided by the Society for Vascular Surgery.
Endovascular Repair Procedure
The endovascular abdominal aortic aneurysm repair procedure is a less invasive approach to fixing an AAA. Patients with pre-existing medical conditions that predispose them to complications more commonly undergo this procedure. Catheters are advanced through the blood vessels in the groin to bring an endovascular stent graft (also known as an endograft) to the aneurysm site, monitored through X-rays. Once in place, the graft expands (held into place via a metal frame) at the site of the aneurysm to strengthen this area and prevent rupture by directing blood though the graft rather than through the aneurysm site, or area of the weakened artery. This method usually has less scarring and a shorter length of hospital stay. While less invasive, it often requires more frequent follow-ups to ensure that the graft remains in place and continues to function as intended.
Time Frame
According to The Society of Thoracic Surgeons, the operation length of the open abdominal procedure depends on the extent of the repair required coupled with the patient's general health. Post-procedurally, patients are required to stay in the hospital for roughly a week, but this varies based on the patient's condition and the procedure done. Recovery time varies but usually lasts for four to six weeks. In the endovascular approach, the recovery period after surgery reduces to just a few days, while procedure times and hospital stays remain the same. Due to a variety of potential complications with the endovascular approach, physicians request semiannual monitoring visits to ensure no leaking.
Adverse Events
As with all surgical procedures, certain complications can occur. In both types of abdominal aortic aneurysm procedures, patients run the risk of a heart attack and kidney failure during and after the procedure. Additional adverse complications include respiratory tract failure, deprivation of blood supply to the colon and spinal cord, and prosthetic graft infection.
Prognosis
Patients with aortic dissections have mortality rates of almost 10 percent, according to The Society of Thoracic Surgeons. When surgery is required, the risk increases to almost 30 percent. Doctors attempt to decrease a patient's potential for mortality due to the AAA by treating the person with different medications.
References
- "Vander's Human Physiology: The Mechanisms of Body Function"; Eric P. Widmaier, Hershel Raff, & Kevin T. Strang; 2006
- "The Human Body Book: An Illustrated Guide to Its Structure, Function and Disorders"; Steve Parker; 2007
- MedicineNet.com: Abdominal Aortic Aneurysms
- The Society of Thoracic Surgeons: Aortic Aneurysms
- VascularWeb: Abdominal Aortic Aneurysms
