[Replantation of IMA and accessory right RA during infrarenal AAA repair and a current view on indications for IMA replanting].

INTRODUCTION: Replanting the inferior mesentery artery during infrarenal aortic aneurysm repair is a measure which might prevent development of colon ischemia under certain circumstances. These circumstances and patients who would benefit from this procedure are not well defined.

CASE REPORT: 64-year old man underwent an elective operation on infrarenal AAA at our institution in December 2009. From preoperative CT angiography we knew about the accessory right renal artery branching directly from AAA and bilateral occlusion of hypogastric arteries. We performed open resection of AAA with implantation of a bifurcated graft. Proximal anastomosis was situated below renal arteries, distal anastomoses were bilaterally constructed on external illiac arteries. The accessory right renal artery was anastomosed into the right limb of the graft and IMA was replanted into the body of the graft. Postoperative recovery of the patient was uneventful. His follow-ups 3 and 6 months after the operation have been showing good clinical state of the patient, absence of abdominal complaints and normal levels of urea and creatinine. CT angiography which was performed 3 months after the operation discovered an occlusion of the reimplanted IMA, but patent replanted accessory right renal artery.

DISCUSSION: Assessment of collateral circulation of large intestine during infrarenal AAA repair is influenced by many preoperative and intraoperative factors. Most surgeons judge the adequacy of the collateral circulation by IMA backbleeding combined with inspection of sigmoid colon after restoring aortic flow. There have been numerous attempts to replace this subjective approach with more objective methods like intraoperative colon mucosal saturation measurement, laser Doppler flowmetry, IMA stump pressures, photophletyzmographic technique. Even though these methods describe conditions when a collateral circulation of rectosigmoid is inadequate after IMA ligature, they are unable to fully eliminate the occurrence of colon ischemia because of its multifactorial nature. Solving the problem of collateral circulation of the large intestine represents only a part of the obstacle presented by colon ischemia after infrarenal AAA repair.

CONCLUSION: IMA replantation during infrarenal AAA repair does not fully prevent an occurance of colon ischemia. On the other side, this moneuver does not increase perioperative morbidity, nor prolongs an operation significantly. Our policy is to replant IMA whenever we thing the circulation of large intestine is under threat or in borderline situations.