The Long-Term Durability of Intraoperatively Placed of Palmaz Stents for the Treatment of Type Ia Endoleaks After EVAR of AAA

Abstract

Introduction: Type Ia endoleak is associated with aneurysm expansion and rupture and aggressive treatment is recommended as soon as possible. Proximal Palmaz stents are one treatment alternative with well proven short-term results. However, little is known about the long-term. This study aims to study the long-term results of the intraoperative placement of Palmaz stent for the treatment of proximal (Type Ia) endoleaks during EVAR of AAA. Methods: Patients receiving intraoperative proximal Palmaz stent due to type Ia endoleak between 1998 and 2012 were reviewed retrospectively concerning pre-, intra- and post-operative data. Pre-operative and follow-up imaging was reviewed for anatomical changes for AAA sac and at different visceral levels of the aorta (Celiac trunk, SMA, Lowest renal artery and 9 mm below lowest renal). Survival was calculated with life tables. Relative survival comparing acute (ruptured and symptomatic) with elective EVAR patients concerning patients with follow-up ≥3 months was also performed. For the anatomical changes, Wilcoxon signed rank test was used for comparisons of significance. For the life tables, log-rank test was used. Results: One hundred and twenty five patients were included (83 elective, 22 ruptures and 20 symptomatic). Thirty-six (34%) patients out of 105 with an available pre-operative CT were outside the IFU, while 43 (41%) had conical aortic necks. Nine patients died peri-operatively. Median follow-up was 43 (15–72) months. Six patients had late AAA-related deaths. There were 51 re-interventions of which 7 were type Ia endoleak related. Primary and assisted freedom from type Ia endoleak five years post-operatively was 84 ± 4% and 89 ± 3%, respectively. The visceral aortic diameter increased significantly between the 1st and the latest post-operative images in 15/91 (16%), 12/91 (13%), 34/91 (37%) and 30/91 (33%) patients at the levels of coeliac trunk, SMA, lowest renal artery and 9 mm distal to lowest renal artery, respectively. Sixteen (18%) out of these 91 patients exhibited ≥5 mm AAA expansion. Five-year primary, primary-assisted and secondary success were 55 ± 5%, 66 ± 5% and 71 ± 5% respectively. For patients with follow-up ≥3 months, there was no significant (P > 0.05) difference in survival, clinical success or assisted type Ia endoleak for the acute (N = 30) versus elective (N = 76) EVAR. There was a significantly higher primary freedom from type Ia endoleak (P = 0.025) in elective EVAR when comparing with acute EVAR. Conclusion: Intraoperatively placed Palmaz stents seem to confer a high freedom from type Ia endoleaks on the long-term. Palmaz stents are an acceptable bailout solution for intraoperative type Ia endoleaks, especially in the acute setting, but should not be used in extending the application of elective infrarenal EVAR to more demanding anatomies. Disclosure of Interest: None Declared.