A Systematic Review and Meta-Analysis of Laparoscopic Ligation of the Inferior Mesenteric Artery for the Treatment of Type II Endoleaks

Objectives: Type II endoleak (T2E), often generated by persistent retrograde flow through the inferior mesenteric artery (IMA) is the most frequent complication following endovascular aortic aneurysm repair (EVAR). T2E treatment revolves around transarterial and translumbar embolization of the feeding artery and/or sac, with mediocre results. The aim of this study is to assess the safety feasibility and efficacy of laparoscopic IMA ligation for the treatment of T2E. Methods: We conducted a systematic electronic research on Medlin, Scopus, EMBASE, and Cochrane Library according to Preferred Reporting Items for Systematic Review and Meta-Analysis protocol (PRISMA) for articles published up to February 2022, describing laparoscopic IMA ligation for the treatment of T2E. Publications describing hand assisted or prophylactic IMA ligation were excluded. A metanalysis was performed utilizing both the random and common effects model and the DerSimonian and Laird method. Additionally, we carried out a post hoc power analysis. Results: Fifteen studies, including one prospective case series (CS), five retrospective CS and nine case reports, including 33 patients (91% male) met the inclusion criteria. The mean abdominal aortic aneurysm diameter at the time of diagnosis was 58.8 mm. The mean operational duration was 117.5 minutes. The mean follow-up for the included studies was 17 months. The mean reported time of T2E identification was 9.1 months post-intervention, while the mean reported aneurysmal sac diameter increase at the time of diagnosis was 11.5 mm. type a (T2aE) and type b (T2bE) patterns were 57.6% and 42.4% respectively. Six CS incorporating 24 patients were included in the meta-analysis. The pooled technical success and postoperative mortality rates are 100% (95% CI: 93.13-100), (I-2 = 0.0%, p = 0.99) (power = 99%) and 0.00% (95% CI: 0.00-6.87) (I-2 = 0.0%, p = 0.99). The pooled reintervention and conversion to open surgical repair rates are 15.08% (95% CI: 0.79-37.28), (I-2 = 0.0%, p=0.66) (power = 13.6%), and 0.69% (95% CI: 0.00-14.80) (I-2 = 0.0%, p = 0.99) (power = 7.05%) respectively. Conclusions: We demonstrated the safety and feasibility of IMA ligation for the treatment of T2E. Definitive conclusions about its efficacy cannot be drawn due to underpowered results warrantying further research. Identification and proper classification of T2E remain an obstacle affecting treatment outcomes and reintervention rates throughout the entire spectrum of available treatments.