Epidemiology of Aortic Aneurysm

The epidemiology of abdominal aortic aneurysm (AAA) disease has been well described over the preceding 50 years. This disease primarily affects elderly males with smoking, hypertension, and a positive family history contributing to an increased risk of aneurysm formation. The aging population as well as increased screening in high-risk populations has led some to suggest that the incidence of AAAs is increasing. The National Inpatient Sample (1993–2003), a national representative database, was used in this study to determine trends in mortality following AAA repair in the United States. In addition, the impact of the introduction of less invasive endovascular AAA repair was assessed. Overall rates of treated unruptured and ruptured AAAs remained stable (unruptured 12 to 15/100,000; ruptured 1 to 3/100,000). In 2003, 42.7% of unruptured and 8.8% of ruptured AAAs were repaired through an endovascular approach. Inhospital mortality following unruptured AAA repair continues to decline for open repair (5.3% to 4.7%, P = 0.007). Mortality after elective endovascular AAA repair also has statistically decreased (2.1% to 1.0%, P = 0.024) and remains lower than open repair. Mortality rates for ruptured AAAs following repair remain high (open: 46.5% to 40.7%, P = 0.01; endovascular: 40.0% to 35.3%, P = 0.823). These data suggest that the numbers of patients undergoing elective AAA repair have remained relatively stable despite the introduction of less invasive technology. A shift in the treatment paradigm is occurring with a higher percentage of patients subjected to elective endovascular AAA repair compared to open repair. This shift, at least in the short term, appears justified as the mortality in patients undergoing elective endovascular AAA repair is significantly reduced compared to patients undergoing open AAA repair.