Aortic Brief History of Acute

Aortic

Brief history of acute aortic dissections

An aortic dissection is a tear in the inner lining of the aorta. Two types of aortic dissections exist: type A and type B. Type A acute aortic dissections are the most serious type of complaint. The type A dissection begins in the aorta and progresses throughout the vessel, extending far beyond the original tear -- as long as the arteries in the leg. This dissection necessitates immediate medical attention. In contrast, type B is localized, and only in the descending aorta, although in some cases it may extend into the abdomen. Type B can be treated with aggressive medical interventions, such as blood pressure reduction through diet and pharmaceuticals.

Type A requires immediate surgery because stroke, heart attack, congestive heart failure, or massive internal hemorrhaging may occur at any time (Aortic dissection, 2011, Columbia Surgery). Such an acute aortic rupture can result in blood loss; a failure of the aortic valve and rapid heart failure; loss of blood from the coronary arteries, causing a heart attack; or "accumulation of blood in the pericardium (the sac that contains the heart)" can prevent the heart from pumping blood (Aortic dissection, 2011, Columbia Surgery).

Aortic dissection can also result in malperfusion syndrome, when restricted blood flow results in the failure of other organs, most typically the kidneys and intestines. The result may be temporary or permanent kidney failure and intestinal injury and the need for a bowel resection (Aortic dissection, 2011, Columbia Surgery). Malperfusion syndrome can occur in both types of aortic dissection, and will warrant surgery even in type B patients.

Less acute type B conditions often produce no symptoms, and even type A may not produce symptoms, earning aortic dissections the nickname of 'the silent killer.' However, when the condition becomes acute, it can cause many of the symptoms of a heart attack, including crushing pain in the chest, a sense of doom, high blood pressure, and shortness of breath. New technologies for the treatment of type A aortic dissections include using dissection, and selective perfusion to protect the brain. "Valve sparing root replacements may be performed to replace the entire ascending aorta without leaving residual dissection behind" (Type A, 2011, Columbia Surgery). For type B, the usual prescription is blood pressure control, given the risks of surgery. However, endovascular stent grafting is often offered as an alternative and less invasive treatment (Type B, 2011, Columbia Surgery).

When operating, the femoral artery is usually selected for aortic cannulation. But in some patients, "although the femoral artery seems to be intact, its use for aortic return carries a high risk of cerebral embolism because of the atheromatous changes in the thoracic aorta. Alternatively, surgeons may use the axillary artery in the presence of peripheral artery disease or femoral artery dissection" although "the use of the axillary artery for cannulation can be troublesome because of the vessel's small diameter" (Yamamoto et al. 2001). Aortic cannulation through the apex of the left ventricle and the aortic valve is recommended as the safest place of entry (Yamamoto et al. 2001).