O-126 - THE ASSOCIATION BETWEEN D-DIMER LEVEL AT 1 YEAR AFTER EVAR AND SAC DIAMETRE CHANGE IN PATIENTS WITH PERSISTENT TYPE 2 ENDOLEAK

TOPIC:
Abdominal Aortic Aneurysms
AUTHORS:
Sugimoto M. (Division of Vascular and Endovascular Surgery, Nagoya University Graduate School of Medicine ~ Nagoya ~ Japan) , Sato T. (Division of Vascular and Endovascular Surgery, Nagoya University Graduate School of Medicine ~ Nagoya ~ Japan) , Ikeda S. (Division of Vascular and Endovascular Surgery, Nagoya University Graduate School of Medicine ~ Nagoya ~ Japan) , Kawai Y. (Division of Vascular and Endovascular Surgery, Nagoya University Graduate School of Medicine ~ Nagoya ~ Japan) , Tsuruoka T. (Division of Vascular and Endovascular Surgery, Nagoya University Graduate School of Medicine ~ Nagoya ~ Japan) , Niimi K. (Division of Vascular and Endovascular Surgery, Nagoya University Graduate School of Medicine ~ Nagoya ~ Japan) , Banno H. (Division of Vascular and Endovascular Surgery, Nagoya University Graduate School of Medicine ~ Nagoya ~ Japan)
Introduction:
Although the optimal management of type 2 endoleak (T2EL) after endovascular aortic aneurysm repair (EVAR) has been controvertial, current ESVS guidelines regard sac shrinkage≥10mm as low risk of failure, with less frequent follow-up even in the presence of T2EL. In contrast, the sac enlargement is considered as an indication for reintervention. While the management of T2EL depends on sac diametre change, there is no established methods to predict which aneurysm with T2EL might shrink or enlarge so far. Recent studies regarding the pathophysiology of aneurysm suggested that unorganized thrombus play a central role for sac enlargement and that sac shrinkage could be induced by suppression of intrasaccular clotting renewal besides mechanical exclusion of aneurysm by endografts. [1] In this context, we hypothesised that D-dimer level, a marker of fibrin turnover and fibrinolysis, could be related to sac remodeling in patients with T2EL. This study reviewed our patients with persistent T2EL at 1 year, aiming to estimate the impact of D-dimer level on sac diametre change within 5 years after EVAR.
Methods:
A retrospective review of our series of elective EVAR of infrarenal abdominal aortic aneurysm between June 2007 and February 2020. A persistent T2EL was defined as a T2EL confirmed at both 6- and 12-month follow-up with contrast enhanced computed tomography (CECT). [2] Patients with >2-year follow-up, persistent T2EL, and data of D-dimer level at 1 year (DD1Y) were included. Patients with any re-intervention or type 1 or 3 endoleak within 1 year were excluded. Spontaneous sac shrinkage (SpS) was defined as ≥5 mm reduction of aneurysm diameter without any reintervention. [3] Aneurysm enlargement (AnE) was defined as ≥5 mm sac expansion during follow-up. The incidence of SpS and AnE was checked with annual CT follow-up up to 5 years. Among the enrolled patients, the association between DD1Y and sac diametre change within 5 years were analysed.
Results:
mong 615 elective EVAR patients with >2-year follow-up, 434 underwent CECT studies at both 6 and 12 months. 170 patients had isolated T2EL at 6 months. After excluding 15 spontaneous resolutions and 1 type Ia endoleak at 12 months, 154 patients with persistent T2EL were confirmed. 5 patients with any reintervention within 1 year were also excluded. Among residual 149 patients, 60 patients whose DD1Y were available were enrolled in the study. During median follow-up of 49 months [30-67, IQR], 19 SpS were observed. Meanwhile, AnE was observed in 20 patients, and 8 reinterventions were performed. There was no mortality during follow-up. Median DD1Y was 9.35 µg/mL [5.16-15.56, IQR; 0.77-45.13, range]. No significant difference of DD1Y was confirmed between patients with SpS and others. In patients with AnE, however, median DD1Y was significantly higher compared to others (12.30 [6.88-21.90, IQR] vs 7.62 [4.41-13.00, IQR], P=0.024), and ROC curve analysis indicated that the optimal-cut off point was 5.5 µg/mL (AUC=0.681). In univariate analysis, DD1Y≥5.5µg/mL and the occlusion of inferior mesenteric artery were significantly associated with AnE (P= 0.025 and 0.038). Cox regression analysis revealed that DD1Y≥5.5µg/mL had a marginal correlation with AnE (P=0.050, HR [95%CI] 4.315 [1.001-18.602]). Neither DD1Y nor the rate of AnE was significantly different among Zenith, Excluder, and Endurant in the present population.
Conclusion:
The present study suggested that higher D-dimer level at 1 year had potential to predict AnE within 5 years in patients with T2EL. Meanwhile, no correlation with SpS was observed in this small series. Larger study is mandatory to confirm the consistency of these findings and to consider confounders. It should be also elucidated whether any intervention to reduce D-dimer, such as fibrinolysis inhibitors, can suppress AnE through stabilization of intrasaccular clot in the future study.
References:
[1] Sénémaud J, Coscas R, Alsac JM, Castier Y, Pellenc Q, Michel JB. Behind the Scenes of Disappointing Long Term EVAR Results: Pathophysiological Insights and Future Research Leads. Eur J Vasc Endovasc Surg. 2020;60:954-955. [2] Sugimoto M, Banno H, Sato T, Ikeda S, Tsuruoka T, Kawai Y, et al. Factors Associated With Spontaneous Sac Shrinkage in Patients With Persistent Type 2 Endoleaks After EVAR. J Endovasc Ther 2022 [In press] [3] Sugimoto M, Banno H, Sato T, Ikeda S, Tsuruoka T, Kawai Y, et al. Clinical Comparison between Early and Late Spontaneous Sac Shrinkage after Endovascular Aortic Aneurysm Repair. Ann Vasc Surg 2021 ;75:420-429.