Mid-Term Results of Endovascular Abdominal Aortic Aneurysm Repair: Is it Possible to Predict Sac Shrinkage?

Purpose. To evaluate the mid-term results of endovascular repair of abdominal aortic aneurysms and to predict subsequent sac shrinkage. Methods. From December 2006 to April 2010, 114 abdominal aortic aneurysms were treated with stent grafts. The intraoperative sac pressure was measured by a microcatheter. Correlations between the diameter change and relevant factors were determined by a logistic regression analysis. Results. Stent grafts were deployed successfully in all patients. Type-2 endoleaks were noted in 25 patients (22%); there were no type-1 or type-3 endoleaks at discharge. The clinical success rate was 99%. The diameter was reduced in 40 patients (56%) but remained unchanged in 32 (44%). There were no aneurysms that increased in diameter. At 2 years after the repair the rate of cumulative survival was 87% and freedom from secondary intervention was 95%. The sac pressure index after stent grafting with a reduced diameter was 0.56 +/- 0.11 and that of patients with an unchanged diameter was 0.52 +/- 0.14. There were no significant differences between the two groups. Persistent type-2 endoleaks had a slightly negative effect on sac shrinkage (P = 0.052). Conclusions. The mid-term results of endovascular aneurysm repair were satisfactory. Although it was difficult to predict the fate of a sac after stent grafting, persistent type-2 endoleaks were observed to have a slightly negative impact on sac shrinkage.