Outcomes of Extended Endovascular Aortic Repair for Aorto-Iliac Aneurysm with Internal Iliac Artery Occlusion

Prospective clinical study for claudication after endovascular aneurysm repair involving hypogastric artery embolization

Purpose

This prospective study aimed to assess the prognosis of claudication after endovascular aneurysm repair (EVAR) involving hypogastric artery (HGA) embolization.

Methods

Patients who were scheduled to undergo EVAR involving bilateral or unilateral HGA embolization (BHE or UHE, respectively) between May 2017 and January 2019 were included in this study. Patients underwent the walk test preoperatively, one week postoperatively, and monthly thereafter for six months. The presence of claudication and the maximum walking distance (MWD) were recorded. A near-infrared spectroscopy monitor was placed on the buttocks, and the recovery time (RT) was determined. A walking impairment questionnaire (WIQ) was completed to determine subjective symptoms.

Results

Of the 13 patients who completed the protocol, 12 experienced claudication in the 6-min walk test. The MWD was significantly lower at one week postoperatively than preoperatively. The claudication prevalence was significantly higher at five and six months postoperatively after BHE than after UHE. BHE was associated with longer RTs and lower WIQ scores than UHE.

Conclusions

We noted a trend in adverse effects on the gluteal circulation and subjective symptoms ameliorating within six months postoperatively, with more effects being associated with BHE than with UHE. These findings should be used to make decisions concerning management strategies for HGA reconstruction.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00595-022-02502-x.

Gluteal Blood Flow Monitoring in Endovascular Aneurysm Repair With Internal Iliac Artery Embolization

BACKGROUND

When an internal iliac artery (IIA) has to be embolized during endovascular aneurysm repair (EVAR), buttock claudication sometimes poses problems. However, there is no established method to evaluate intraoperative blood flow to the gluteal muscles.

METHODS AND RESULTS

Gluteal regional oxygen saturation (rSO2) was monitored using near-infrared spectroscopy (NIRS) during surgery, and changes in rSO2were compared with treatment results. Twenty-seven patients who underwent EVAR and IIA embolization at our institution between April 2019 and May 2020 were included in this study. The association between intraoperative changes in rSO2and postoperative incidence of buttock claudication was analyzed. Furthermore, the presence or absence of communication between the superior and inferior gluteal arteries and the intraoperative changes in rSO2were compared to ascertain whether rSO2reflects blood flow change. Postoperative buttock claudication occurred in 4 of 19 patients (21%) with unilateral occlusion of IIA and in 4 of 8 patients (50%) with bilateral occlusion of IIAs. rSO2was found to decrease significantly further in patients with buttock claudication than in patients without buttock claudication (-15±12% vs. -4±16%, P<0.05). In addition, rSO2was predominantly lower in patients without the communication between the superior and inferior gluteal arteries than in those with the communication.

CONCLUSIONS

Gluteal rSO2is useful as an indicator of intraoperative gluteal blood flow.

Clinical outcomes after internal iliac artery embolization prior to endovascular aortic aneurysm repair

BACKGROUND

Aortic anatomy is important in determining the success or failure of endovascular aortic aneurysm repair (EVAR). Endoleak is another issue which should be addressed for a long-term durability of the procedure. Internal iliac artery (IIA) embolization is required to prevent type II endoleak when the iliac landing zone is not sufficient such that the iliac limb should be extended down to the external iliac artery (EIA). Pelvic ischemia is an important complication of IIA embolization, but its incidence and severity is not exactly known. Our experience suggests this to be common but not severe. In this study we reviewed the clinical outcomes of patients who underwent IIA embolization to facilitate EVAR at one of the major tertiary medical centers in South Korea.

METHODS

We performed a retrospective review of the patients who underwent IIA embolization prior to EVAR between November 2005 and June 2018 at a single tertiary medical center in South Korea. Patients were interviewed via telephone to determine the severity of buttock claudication according to a previously defined pain scale.

RESULTS

The majority of 139 patients in both the unilateral and bilateral IIA embolization groups experienced no (N.=83, 60.0%) or mild (N.=51, 36.7%) buttock claudication. Only three patients in the unilateral IIA embolization group reported that their symptoms affected daily life, but without need for any measures for pain relief. Symptom duration was longer in the bilateral embolization group (12.6 months) compared to the unilateral group (6.6 months) without statistical significance (P=0.559). There were no critical complications such as buttock necrosis, spinal cord ischemia, or ischemic colitis.

CONCLUSIONS

Based on our experience, IIA embolization does cause buttock claudication of a certain degree. However, the most of them experienced mild discomfort rather than such symptoms severely affect their quality of life. Considering the risks of general anesthesia and complications of surgical procedures, IIA reconstruction along with EVAR may not be necessary.

Use of Numerical Simulation to Predict Iliac Complications During Placement of An Aortic Stent Graft

BACKGROUND

During endovascular aneurysm repair (EVAR), complex iliac anatomy is a source of complications such as unintentional coverage of the hypogastric artery. The aim of our study was to evaluate ability to predict coverage of the hypogastric artery using a biomechanical model simulating arterial deformations caused by the delivery system.

METHODS

The biomechanical model of deformation has been validated by many publications. The simulations were performed on 38 patients included retrospectively, for a total of 75 iliac arteries used for the study. On the basis of objective measurements, two groups were formed: one with "complex" iliac anatomy (n = 38 iliac arteries) and the other with "simple" iliac anatomy (n = 37 iliac arteries). The simulation enabled measurement of the lengths of the aorta and the iliac arteries once deformed by the device. Coverage of the hypogastric artery was predicted if the deformed renal/iliac bifurcation length (L_pre) was less than the length of the implanted device (L_stent-measured on the postoperative computed tomography [CT]) and nondeformed L_pre was greater than L_stent.

RESULTS

Nine (12%) internal iliac arteries were covered unintentionally. Of the coverage attributed to perioperative deformations, 1 case (1.3%) occurred with simple anatomy and 6 (8.0%) with complex anatomy (P = 0.25). All cases of unintentional coverage were predicted by the simulation. The simulation predicted hypogastric coverage in 35 cases (46.7%). There were therefore 26 (34.6%) false positives. The simulation had a sensitivity of 100% and a specificity of 60.6%. On multivariate analysis, the factors significantly predictive of coverage were the iliac tortuosity index (P = 0.02) and the predicted margin between the termination of the graft limb and the origin of the hypogastric artery in nondeformed (P = 0.009) and deformed (P = 0.001) anatomy.

CONCLUSIONS

Numerical simulation is a sensitive tool for predicting the risk of hypogastric coverage during EVAR and allows more precise preoperative sizing. Its specificity is liable to be improved by using a larger cohort.

Combined transbrachial and transfemoral strategy to deploy an iliac branch endoprosthesis in the setting of a pre-existing endovascular aortic aneurysm repair

This article describes brachial access to position a long sheath in the abdominal aorta in conjunction with a large caliber sheath via the femoral artery ipsilateral to the target site to deliver a 0.018 bodyfloss wire. This bodyfloss wire is inserted into the precannulation port of the iliac branch endoprosthesis (W. L. Gore and Associates, Flagstaff, Ariz), which is then advanced from the groin. Once the bifurcated device is deployed, hypogastric access and stenting is achieved from the upper extremity. This technique is an alternative to safely extend the distal seal while preserving the hypogastric artery and has the advantage of limited iliac bifurcation manipulation.