Intra-Sac Injection of Thrombin During Endovascular Aneurysm Repair to Remedy Type II Endoleak and Promote Sac Shrinkage

Purpose: To evaluate the safety and effectiveness of intra-sac thrombin injection to remedy type II endoleaks (T2ELs) during endovascular aneurysm repair (EVAR). Materials and Methods: 224 cases abdominal aortic aneurysm (AAA) were treated with EVAR. For the 52 cases of intra-operative type II endoleaks and 8 cases of ruptured AAAs, after the grafts were deployed, thrombin was injected into the aneurysm sac through a preset catheter. The occurrence of endoleaks post-EVAR were followed up with by Computed Tomography (CT) angiogram. The diameter and the volume of the aneurysm sac were alsomeasured. Endpoints included incidence of T2ELs, AAA sac shrinkage and re-intervention rate and all-cause mortality. Results: The overall technical success rate was 100%. Fifty-two patients were followed up with for 9-56 (median 24) months. No serious complications were observed during follow-up. The incidence of endoleakwas 5.8% (3/52) during follow-up. The maximumdiameter of the aneurysmdecreased from 61.1 +/- 14.2 mm to 53.7 +/- 10.6 mm, 47.9 +/- 8.3 mm and 43.7 +/- 7.2 mm (87.9%, 78.4% and 71.5% of pre-EVAR) at the 6-month, 1-year and 2-year follow-up, respectively (P <.05). The volume of the aneurysm sac shrank from 236.2 +/- 136.2 cm(3) to 202.6 +/- 114.1 cm(3), 155.6 +/- 68.4 cm(3) and 129.7 +/- 52.4 cm(3) (85.8%, 65.9%, and 54.9% of pre-EVAR) at the 6-month, 1-year and 2-year follow-up, respectively (P <.05). The rate of various endoleaks was 5.8% (3/52) and the re-intervention rate was 1.9% (1/52) in this research. Conclusions: Clinical outcomes show that intra-sac injection of thrombin during EVAR is safe and may be effective in remedying small amount and lowvelocity endoleaks and promoting shrinkage of the aneurysm sac.