Chapter 25: Abdominal Aortic Aneurysmal Disease

GENERAL CONSIDERATION AND HISTORY

Aneurysmal degeneration of the aorta is defined as dilation of the blood vessel 1.5 times of or greater than its normal diameter.¹ Aortic aneurysms carry a significant risk of morbidity and mortality. The UK Small Aneurysms Study found that of 103 recorded ruptured abdominal aortic aneurysm (AAA), 25% died without even reaching the hospital.² Given this, understanding the etiology and diagnosis is of the utmost importance to avoid death from aneurysm rupture.

History of Aortic Aneurysm Disease

Egyptian hieroglyphics illustrated arterial aneurysms thousands of years before year 1 A.D.³ The Greek surgeon Antyllus was one of the first documented to have treated an aneurysm in the second century A.D.⁴ John Hunter performed a successful ligation of the superficial femoral artery to repair a popliteal artery aneurysm in 1785.⁵ In 1817, British surgeon Astley Cooper performed a successful aortic ligation, and on March 6, 1888, the first successful endoaneurysmorrhaphy was first described when Rudolph Matas repaired a brachial artery aneurysm.^4,6 Endoaneurysmorrhaphy involves opening the aneurysmal sac, removing clot, and suturing together the vessel walls to create a more normal arterial lumen. Roughly 60 years later, Charles Dubost successfully resected an AAA and replaced it with a homograft.⁷ In the United States, Denton Cooley and Michael DeBakey performed a similar AAA surgery just months later.⁴ In 1990, Juan Parodi and Julio Palmaz performed what we believe to be the first minimally invasive endovascular approach to repair an AAA in Argentina.⁸ Endovascular techniques have since evolved to allow for complex aortic aneurysm repairs through sub-centimeter incisions in a patient’s groins and/or arm.

Anatomy of Aortic Aneurysm Disease

The aorta is defined by its relation to the aortic arch and its branches. The ascending thoracic aorta refers to the aortic arch as it begins from the aortic valve to the takeoff of the innominate artery. The descending thoracic aorta refers to the thoracic aorta distal to the left subclavian artery and continues toward the diaphragm. The supraceliac aorta refers to the aortic segment between the diaphragmatic hiatus and the celiac axis. The aorta below the diaphragmatic hiatus is referred to as the abdominal aorta. The suprarenal aorta, or visceral aorta, refers to the aortic segment between the celiac axis and the renal arteries, including the superior mesenteric artery (SMA). Finally, the infrarenal aorta refers to the segment between the renal arteries and aortic bifurcation. Of note, the infrarenal aorta includes the origin of the inferior mesenteric artery (IMA), which arises around the level of the third lumbar vertebra. Normal measurements of the aorta are given in Table 25-1.⁹