Long-Term Outcomes of Immediate Repair Compared with Surveillance of Small Abdominal Aortic Aneurysms

Small abdominal aortic aneurysms (no more than 5.5 cm in diameter) are believed to have a low risk of rupture. This study compared two management strategies: immediate surgery and ultrasonographic surveillance followed by surgery if needed. Because of operative mortality, there was an early survival advantage with surveillance, but after eight years, the early-surgery group had gained a survival advantage. Rupture of an abdominal aortic aneurysm is associated with a high fatality rate and is an important cause of sudden death. Low rates of rupture of small abdominal aortic aneurysm were observed among patients enrolled in the United Kingdom Small Aneurysm Trial and the Aneurysm Detection and Management Trial in the United States — 1.0 percent and 0.6 percent per year, respectively. 1 , 2 These low rates of rupture may explain in part why these trials did not demonstrate a five-year survival benefit for patients who were randomly assigned to undergo early elective surgery. Operative mortality rates of 5.8 percent in . . .