Study on Prognosis of Buttock Claudication in Endovascular Aneurysm Repair Cases Involving Internal Iliac Artery Embolization−comparison of Bilateral and Unilateral Embolization

Introduction: Buttock claudication is a complication of internal iliac artery embolization performed simultaneously with endovascular aneurysm repair (EVAR). Although internal iliac artery embolization is a necessary procedure in the endovascular treatment for aneurysms, buttock claudication may become the cause of lowering quality of life after surgery. However, there are few reports that examined its natural prognosis in detail. Methods: This is a prospective study targeting the patients who were scheduled to undergo simultaneous internal iliac artery embolization and for whom EVAR was scheduled for abdominal aortic aneurysm or iliac artery aneurysm. Cases in which walk tests could not be performed for various reasons were excluded. A treadmill walk load test (12% slope, 2.4km/h speed) and 6-minute flat surface walk test were performed before and one week after surgery and once every month until 6 months after surgery, and presence or absence of development of claudication, pain-free walking distance (PWD), and maximum walking distance (MWD) were examined. In addition, in the treadmill walk load test, a near-infrared spectroscopy (NIRS) monitor was attached to the buttocks, and the recovery time (RT) was examined per leg. In addition, subjective symptoms of gait disorders were investigated using Walking Impairment Questionnaire (WIQ) at every test. Results: The subjects were 14, and all were male patients (mean age 78.1±4.3 years). Five cases were excluded after inclusion, due to poor health conditions. In 13 out of 14 cases, a symptom of claudication was observed in the 6-minute flat surface walk test one week after surgery, however, the number of cases complaining of claudication decreased with time (Table 1). Cases in which claudication remained at 6 months post-surgery were all bilateral embolization cases. When we divided cases into 6 bilateral embolization cases and 8 unilateral embolization cases, no significant difference was seen in the incidence rate of claudication at one week post-surgery. However, at 5, and 6 months post-surgery, there were significantly more cases with claudication in bilateral embolization cases(Table 1). In subjective assessment by WIQ, bilateral embolization cases were significantly worse or showed a tendency of getting worse for pain related items at 5 months post-surgery (p < 0.01), for distance related items at 4 and 5 months post-surgery (p=0.01, 0.04), for speed related items at 3, 4, 5 months post-surgery (p=0.04, 0.06, 0.04), and for staircase related items at 4 and 5 months post-surgery (p=0.09, < 0.01). There was no significant difference in the 6-monute walk distance between the bilateral and the unilateral embolization cases, and a similar result was obtained even when it was adjusted by preoperative walk distance. The RT by NIRS was significantly prolonged at 3 and 4 months post-operation in the bilateral embolization cases (102±41sec vs 201±32sec, p=0.03, 47±40sec vs 155±40sec, p< 0.01). Conclusion: In the unilateral embolization cases, buttock claudication disappeared within half a year after surgery, whereas claudication significantly remained in the bilateral embolization cases. Because bilateral embolization can affect the circulatory dynamics of the gluteal muscle and subjective symptoms during walking, EVAR must be performed with reconstruction of internal iliac artery in mind.Table 1Cases in which claudication remained Disclosure: Nothing to disclose