When your aorta is healthy, its elastic walls expand and contract easily. However, when your aorta is diseased, the areas of weak, abnormal tissue bulges or balloons out. The stress of high-pressure blood flow on this abnormal tissue, which becomes weak and thin, puts this vital blood vessel at risk of tearing or rupturing.
Thoracic aortic disease may be caused by several different conditions and may occur in both males and female of any age. When the underlying cause is genetically based, more than one family member may be affected. Thoracic aortic disease is serious because weak, fragile aortic tissue under high pressure may tear or rupture, causing life-threatening bleeding. Early detection can prevent emergencies that too often result in injury or loss of life.
Types of Aortic Disease
Bulging or enlargement of a blood vessel due to weakness of vessel wall.
A tearing of the inner lining of the aortic wall, allowing blood to enter and split the layers of the aortic wall. Blood may travel within the layers of the aorta, creating a "false" channel, sometimes called a false lumen.
Bleeding within the wall of the aorta, a variation of classic aortic dissection. Ulceration of atherosclerotic plaque penetrates into the aortic wall.
Diagnostic testing is the first step in establishing a treatment strategy. A high degree of accuracy in the performance and interpretation of these tests is particularly critical in the evaluation of aortic disease:
Medical treatment and lifestyle changes are specified for each individual and will include blood pressure optimization and lifestyle recommendations. Blood pressure medications, such as beta-blockers, ACE inhibitors, ARBs and calcium channel blockers, are commonly prescribed. However, use of diuretics may be beneficial in patients who are prone to weight gain as a result of water retention. Generally, an optimal systolic blood pressure range prior to surgery is between 105 and 110 during normal activity.
Lifestyle recommendations address diet, exercise and smoking cessation. It is very important that those with aortic disease do not smoke either actively or passively. A diet low in fat and carbohydrates and high in fiber and protein is recommended. Exercise is generally extremely helpful for aortic aneurysm patients, and they are encouraged to be active. Usually power walks of 15 to 30 minutes two to three times daily are recommended. However, heavy lifting, which puts pressure on the aorta, is prohibited.
When the risk of aortic dissection or rupture is greater than that associated with surgery, elective surgery is offered to replace the diseased section of the aorta with a Dacron graft. If necessary the aortic valve may also be either repaired or replaced. The following are Thoracic Aortic surgical options:
Thoracic Aortic Resection
The surgical removal of some portion of diseased aorta. A Dacron graft is used to replace your diseased aortic tissue and is compatible with your body, so rejection is not an issue and calcification does not occur.
Hypothermic Circulatory Arrest
Surgeries that remove a portion of the aorta temporarily stop blood circulation under controlled conditions. To prevent injury to your brain, hypothermic circulatory arrest, also called total circulatory arrest (TCA), is used to temporarily suspend blood flow under very cold body temperatures. At these cold temperatures, cellular activity levels slow significantly, and blood circulation can be stopped for up to 30 to 40 minutes without harm to you. This allows surgery to safely be performed on your aorta. A majority of thoracic aortic surgery patients will need a short TCA time of 15 to 30 minutes.
Selective Cerebral Perfusion
Another safety procedure that may be used during hypothermic circulatory arrest to protect your brain is selective cerebral perfusion, which ensures oxygenated blood reaches your brain. With selective cerebral perfusion, the surgeon will make a second incision in your upper chest and place a cannula in an artery to deliver blood to your brain while the rest of your circulation is stopped. This helps prevent brain injury during hypothermic circulatory arrest. When the cannula is removed, the incision will be sutured and closed.