Short-term and long-term results of a randomized study comparing high tie and low tie inferior mesenteric artery ligation in laparoscopic rectal anterior resection: subanalysis of the HTLT (High tie vs. low tie) study

Abstract

Background: In rectal anterior resection, a clear consensus regarding the optimal level of inferior mesenteric artery (IMA) ligation does not exist because of a lack of randomized trials. We conducted a randomized trial to determine if the IMA should be tied at the origin (high tie, HT) or distal to the left colic artery (low tie, LT) (HTLT study). This study is a subanalysis of HTLT study for laparoscopic surgery. Methods: All candidates were randomly divided into the HT or LT groups. The lymph node dissection around the origin of the IMA was performed in the LT group. The stratified factor was the approach (open or laparoscopy). Evaluation parameters were operative factors, short-term and long-term results. In the present study, laparoscopic surgeries were examined as subgroup analysis. Results: From June 2006 to September 2012, 331 patients were registered. Two hundred and fifteen patients (107 for HT: 108 for LT) underwent laparoscopic surgeries. There was no difference between the groups in background. The incidence of anastomotic leakage (HT: LT %) showed no significant differences for grade 2 or higher (11.2:9.3), and grade 3 or higher (2.8:4.6). There were no differences in operative time (200:205 min), blood loss (15:15 ml), number of dissected lymph nodes (22:20), and postoperative hospital stay (10:10 days). The incidence of bowel obstruction in HT was significant (3.7 vs. 0%, p = 0.043). There were no significant differences in overall survival (5-year: 91.3 vs. 90.2%, p = 0.850) and disease-free survival (5-year: 83.2 vs. 78.0%, p = 0.525). There were no differences in the first recurrent site and death reason between both groups. The risk factors for leakage were being male and an anastomotic level in a multivariate analysis by logistic regression. Conclusion: The IMA ligation level was unrelated to anastomotic leakage. No significant difference was detected in long-term results between HT and LT.