Aim: To investigate the relation between the number of preoperative patent side branches and the presence or absence of postoperative endoleaks, and to study the fate of patent branches after operation.
Patients and methods: Thirty consecutive patients were included. Cine mode viewing of axial CT angiography images was applied to detect infrarenal aortic side branches. The position of side branches relative to the renal arteries, branch patency and run-off pathways were studied.
Results: A total of 160 patent side branches were found. All patients had two or more patent side branches. A patent inferior mesenteric artery was found in 22/30 patients (73%). Postoperative CT scans revealed major endoleaks in five patients (16%) and minor endoleaks in eight (27%). There was no significant difference in the number of preoperative patent side branches in patients with a completely thrombosed aneurysm sac (five; range 2-8) compared to patients with postoperative endoleaks (six; range 3-9; p = 0.12). Backbleeding from patent side branches as the sole cause of endoleak was seen in one patient only (3.3%).
Conclusion: Postoperative endoleaks are not related to the number of preoperative patent side branches. In patients without endoleaks, contrast enhancement of side branches was repeatedly seen in the vicinity of the aneurysm wall. Although close follow-up of these branches is warranted, they did not affect the outcome of endovascular aneurysm repair.