Reduction in ruptured aortic aneurysms is not due to increases in endovascular repairs

We sought to determine if the shift from open abdominal aortic repair to endovascular methods has affected the incidence of rupture of abdominal aortic aneurysms (rAAA). The Nationwide Inpatient Samples 2001 to 2007 was used. The incidence of rAAA and myocardial infarction (MI) as well as the number and type of aneurysm repairs were tabulated. There were no significant changes in the number of diagnosed (56,991 to 51,122; P = 0.26) and repaired (45,828 to 43,900; P = 0.79) abdominal aortic aneurysms between 2001 and 2007. Open abdominal aortic repair decreased from 31,989 to 13,876 (P < 0.001) whereas the number of endovascular aneurysm repairs increased from 13,839 to 30,025 (P < 0.001). In the same time, rAAA decreased from 7,749 to 5,267 (-32%, P < 0.001). The reduction of rAAA was greatest (-35.5%) in patients 65 to 84 years of age and less in patients 85 years and older (-15%). The number of MI decreased from 773,871 to 624,936 (P = 0.005). The decrease in rAAA was significantly correlated with decreases in MI (r = 0.97, P = 0.0003). Although endovascular aneurysm repair increased, the overall application of abdominal aortic aneurysms repair did not change and does not account for the reduction in rAAA. It is more likely that environmental or other risk factor modifications also predisposing to decreases in MI account for the reduction in rAAA.