Abdominal Aortic Aneurysm - Erler Zimmer

Abdominal Aortic Aneurysm - Erler Zimmer

Clinical History

This 70-year-old man, with a history of mild gastro-oesophageal reflux, presented to the Alfred Hospital with a sudden onset of severe upper abdominal pain radiating to the left shoulder tip. On examination, he displayed distress, hyperventilation, a pulse rate of 87/min, and a blood pressure of 140/90 mm Hg. Abdominal examination revealed board-like rigidity and diminished bowel sounds. Emergency laparotomy revealed no evidence of a ruptured viscus; the pancreas appeared normal, but an unruptured abdominal aortic aneurysm was noted. Subsequent endoscopy revealed a ruptured oesophageal ulcer, and a Celestin tube was inserted. The patient developed localized infective complications, pulmonary edema, and congestion, ultimately succumbing 19 days after admission.

Pathology

The specimen comprises the lower abdominal segment of the aorta, common iliac vessels, and proximal portions of the internal and external iliac arteries. A large 10 x 7 cm aneurysm is situated below the origin of the renal arteries, extending to the aortic bifurcation. The aneurysm, with its severe thinning of the abdominal aorta wall, is partly lined by a laminated thrombus, indicating the chronic nature of the process. Evidence of recent thrombus is present on the luminal surface. Some aneurysmal dilatation of the common iliac and (opened) proximal left external iliac artery is also apparent. The upper end of the specimen shows multiple focally ulcerated atheromatous plaques in the abdominal aorta. No evidence of rupture is observed.

Further Information

Abdominal aortic aneurysm (AAA or triple A) is characterized by a localized enlargement of the abdominal aorta (diameter >3 cm or more than 50% larger than normal). Typically asymptomatic, except during rupture, large aneurysms may be palpable on abdominal examination. Abdominal, back, or leg pain may occur occasionally, depending on location and size. Rupture may result in abdominal or back pain, sudden low blood pressure with loss of consciousness, and often leads to death. AAA's are most common in individuals over 50 years of age, especially in men with a family history of the disease. Additional risk factors include smoking, high blood pressure, and other heart or blood vessel diseases. AAAs are also associated with genetic abnormalities, including Marfan’s syndrome and Ehlers-Danlos syndrome, and about 85% occur below the kidneys.