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Complex Aorta Surgery

The aorta is the large artery that leaves the heart and provides oxygen-rich blood throughout the body.

Many diseases and conditions can cause the aorta to dilate (widen) or dissect (tear) increasing your risk for future life-threatening events. These conditions include:

  • atherosclerosis (hardening of the arteries)
  • hypertension (high blood pressure)
  • genetic conditions (such as Marfan Syndrome)
  • connective tissue disorders (such as Ehler-Danlos disorder, polychondritis, scleroderma, osteogenesis imperfecta, polycystic kidney disease, and Turners Syndrome)
  • injury

An aortic dissection, usually caused by high blood pressure, is a condition that forces the layers of the wall of the aorta apart through increased blood flow. Over time, the pressure of the blood flow can cause the weakened area of the aorta to bulge like a balloon, stretching the aorta, causing severe, sharp, tearing pain in your chest and back.

When is surgery needed to treat aortic disease?
Surgery is needed to treat aortic disease for various reasons. A primary cause for surgery is when an artery wall in the aorta weakens and the wall abnormally expands or bulges as blood is pumped through it. This bulging is called an aortic aneurysm.

An aneurysm can develop anywhere along the aorta:   
  • Aneurysms that occur in the section of the aorta that runs through the abdomen (abdominal aorta) are called abdominal aortic aneurysms.
  • Aortic aneurysms that occur in the chest area are called thoracic aortic aneurysms and can involve the aortic root, ascending aorta, aortic arch or descending aorta.
  • Aneurysms that involve the aorta as it flows thru both the abdomen and chest are called thoracoabdominal aortic aneurysms. 

Is an aortic aneurysm serious?
Aortic aneurysms are the 13th leading cause of death in the United States. Research has shown that patients with large thoracic aneurysms are more likely to die of complications associated with their aneurysms than from any other cause.

What types of surgery are used to treat aortic disease?

During the last ten years, 21% of open great vessel procedures performed at Cleveland Clinic were for life-threatening acute aortic dissections.

A variety of complex aortic surgery procedures are performed. Ascending aorta, aortic arch, descending aorta, thoracoabdominal repairs and thoracic aorta endovascular stent graft procedures are all performed by a multidisciplinary team.

Hybrid Elephant Trunk Procedure
The hybrid elephant trunk procedure is one commonly used complex aortic operation recommended for patients who have extensive aortic aneurysms as well as several coexisting medical conditions, particularly respiratory problems.
The elephant trunk procedure is a two-stage procedure used to treat extensive aneurysms involving both the ascending aorta and aortic arch, and the descending thoracic or thoracoabdominal aorta.

Anatomic Illustration of Two-Stage Procedure

elephanttrunkpreThe elephant trunk procedure was used to treat a 65-year-old woman who had a leaking aneurysm, severe emphysema, and a leaky aortic valve.
elephanttrunk1

In the first stage, surgeons used a traditional incision in the sternum to replace the aortic valve, ascending aorta and arch, and placed an “elephant trunk” graft that hangs in the descending aorta. Shaped in a tubular form, the elephant trunk graft is made from Dacron, which is a synthetic material that is used to replace or repair blood vessels. The aorta was then wrapped at the diaphragm, and superior mesenteric arteries were bypassed.

[Click here for larger view]
3dCTscan

During the second-stage procedure, a stent graft was placed by using an endovascular approach through the femoral artery to connect the elephant trunk to the lower wrap graft.

[Click here for larger view]

In other cases, an additional incision may be required to place an extra graft to another part of the aorta.

While a high-risk staged procedure, the current techniques used by surgeons has resulted in a 98% survival rate for 142 patients having the first stage of the elephant trunk procedure and 92% survival for the second stage. Late survival was excellent with very low risk of reoperation.
Learn more about our Surgical Outcomes.

The Modified David’s Reimplantation Procedure
Another method to improve the overall outcome in the surgical treatment of an aortic aneurysm is the Modified David’s Reimplantation Procedure. This procedure, developed by Dr. Lars G. Svensson, Director of the Center for Aortic Surgery, Marfan Syndrome and Connective Tissue Disorders Clinic at the Cleveland Clinic, is used to treat an aortic root aneurysm.
 

aorticroot

What is an aortic root aneurysm?
Occurring at the aortic root (the section of the aorta that is attached to the heart), an aortic root aneurysm can cause a life-threatening condition called aortic dissection. In this condition, blood flows through a tear in the inner layer of the aorta, causing the layers to separate. Blood flow becomes interrupted and causes the arterial wall to burst.

How is it treated?
The David’s valve-sparing aortic root replacement method is a surgical treatment for aortic root aneurysms. With this method, the aneurysm is repaired while the patient’s own aortic valve is preserved. If the patient’s aortic valve is diseased or cannot be used during the surgery, a bioprosthetic valve may be used.


What is the Modified David’s Reimplantation Procedure?
While the David’s valve-sparing aortic root replacement method has many benefits, it is also a technically difficult procedure. Dr. Svensson’s Modified David’s procedure helps the surgeon determine the appropriately sized aorta graft, maintain the left ventricular outflow tract (the passageway out of the left ventricle), and improve outcomes when using the valve-sparing method.
(insert graphic: modified david procedure)

With the Modified David’s approach, the surgeon uses a special piece of equipment called a Hegar’s dilator to ensure the outflow tract size of the aortic root is maintained, a more normal aortic root is established, and valve function is improved. Early results show the Modified David approach is successful.

Surgeons have performed over 120 Modified David Reimplantation procedures with no deaths and 97% freedom from reoperation at 10 years.

Endovascular Repair
Surgeons are now able to treat some thoracic and thoracoabdominal aneurysms with a promising, new procedure called an endovascular stent graft.

What is an endovascular stent graft?
Endovascular means that surgery is performed inside the body using thin, long tubes called catheters. Through small incisions in the groin, the catheters are used to guide a stent graft through the blood vessels to the site of the aneurysm.

An endovascular stent graft is a small, wire mesh tube (also called a scaffold) that reinforces the weak spot in the aorta. By sealing the area tightly with the artery above and below the aneurysm, the graft allows blood to pass through it without pushing on the aneurysm.

What are the benefits of endovascular repair?
Endovascular repair of thoracic aneurysms is generally less painful and has a lower risk of complications than traditional open-chest surgery because the incisions are smaller.

The use of endovascular stent grafts is particularly beneficial for those patients who are not candidates for open-chest surgery, due to the risks it presents.

While a new and evolving approach, surgeons are paving the way for successful use of endovascular repair of thoracic aneurysms, with careful attention to technique and type of stent graft used through various clinical trials.

In a recent study  using certain type of graft called the Zenith TX1 and TX2 thoracic stent graft (Cook Inc.) in 100 high-risk patients, over half showed improvement in the size of their aneurysm 12 and 24 months following the procedure, in addition to experiencing minimal complications.

Innovations advancing complex aortic surgery
For decades, Cleveland Clinic has been a world leader in medical breakthroughs and innovations. For example, two of the most important advances in modern cardiac care occurred at Cleveland Clinic. The first major contribution was the invention of coronary angiography in 1958. The next milestone was the first coronary artery bypass operation.

  • Developed and refined at Cleveland Clinic beginning in 1967, coronary artery bypass has become the most common heart surgery in the world.
  • Continued advances at Cleveland Clinic are enhancing complex aortic surgery, as well.

Ascending and Descending Aortic Aneurysm Repair
Complex aortic procedures treat patients with aneurysms that need replacement of the aorta from the aortic valve down to the aortic bifurcation (where the aorta separates into two).

axillaryartery
The axillary artery is used to provide ongoing blood perfusion to organs during aortic aneurysm repair and when atherosclerosis (plaque) is present in the ascending aorta.

Cleveland Clinic surgeons offer an innovative approach for ascending and descending aortic aneurysm repair through a single operation that uses combined incisions in the chest and mid-abdomen. During the procedure, the axillary artery (the part of the main artery of the arm) is used to provide ongoing blood perfusion to the body’s organs, and is also used when atherosclerotic plaque is present in the ascending aorta.

Protecting the Brain
A recent study of 403 patients who underwent ascending and aortic arch minimally invasive operations over a 10-year period at Cleveland Clinic showed that blood conservation during surgery is beneficial for the prevention of stroke and neurocognitive outcome.

By following a preoperative protocol that includes patients donating 1 unit of autologous (their own) blood and fresh frozen plasma weekly before surgery (usually 3 to 4 units in total), and donating platelets 3 to 6 days before surgery to be used during the procedure, there was a 98.5% 30-day survival with only 2.0% occurrence of stroke.

While studies are ongoing as to the direct link that blood conservation has on brain function following replacement of the entire aortic arch or an endarterectomy (surgical removal of the lining of an artery), evidence from Cleveland Clinic studies and ongoing experience supports its use.

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