Weighing risks in abdominal aortic aneurysm

Abdominal aortic aneurysms are believed to result from several factors, one probably being inflammation that leads to dilatation, plaque deposition, and degeneration of the arterial wall. Most of these aneurysms are asymptomatic, but abdominal or back pain, shock, and a pulsatile abdominal mass indicate rupture. Initial aneurysm size exceeding 5 cm (2 in.) in diameter and the presence of hypertension and COPD are important predictors of rupture. The overall operative mortality rate with elective repair of an abdominal aortic aneurysm has been reported to range from 0.9% to 5% at university medical centers, and it is only slightly higher at community hospitals. However, with a ruptured aneurysm and emergency repair, the mortality rate rises to about 75%. Several long-term studies using life-table methods have found that 5-year survival rates after aneurysm repair range from 49% to 84%. This rate is significantly better than the 5-year survival rate of patients who did not have an abdominal aortic aneurysm repaired. However, it is not as good as that of the normal age-matched population, probably because many patients with an aneurysm have concomitant coronary artery disease.