Outcome of renal stenting for renal artery coverage during endovascular aortic aneurysm repair

Abstract

Objective To determine the outcome of adjunctive renal artery stenting for renal artery coverage at the time of endovascular abdominal aortic aneurysm repair (EVAR). Methods Between 8/2000 to 8/2008, 29 patients underwent elective EVAR using bifurcated Zenith stent-grafts and simultaneous renal artery stenting. Renal artery stenting during EVAR was performed with endograft “encroachment” on the renal artery ostium (n = 23) or placement of a renal stent parallel to the main body of the endograft (“snorkel”, n = 8). Follow-up included routine contrast-enhanced computed tomography (CT), multi-view abdominal x-rays, and creatinine measurement at 1, 6, and 12 months, and then yearly thereafter. Results 31 renal arteries were stented successfully in 29 patients. All patients with planned renal artery stent placement (n=18) had a proximal neck length < 15mm. Mean proximal neck length was shorter in patients who underwent the “snorkel” technique (6.9 ± 3.1 mm) compared to those with planned endograft encroachment (9.9 ± 2.6 mm). None of the patients with unplanned endograft encroachment had neck lengths < 15mm (mean length: 26.3±10.2 mm). Mean proximal neck angulation was 42.8 ± 24.0 degrees and did not differ between the groups. One patient had a type I endoleak on completion angiography, and 2 additional patients had a type I endoleak on the first postoperative CT scan. All type I endoleaks resolved by the one-month postoperative CT scan. Primary-assisted patency of renal artery stents was 100% at a median follow-up of 12.5 months (range 2 days to 77.4 months). One patient had near occlusion of a renal artery stent noted on follow-up CT scan at 9 months; patency was restored by placement of an additional stent. One patient required dialysis following sustained hypotension from a right external iliac artery injury which resulted in prolonged post-operative bleeding. Mean creatinine at baseline was 1.1 ± 0.3 mg/dl, 1.2 ± 0.5 mg/dl at 1 month follow-up, and 1.2 ± 0.5 mg/dl at 2 years of follow-up. There were no cases of late type I endoleaks (>one month postoperatively) or stent-graft migration. Conclusions Adjunctive renal artery stenting during endovascular AAA repair using the “encroachment” and “snorkel” techniques is safe and effective. Short and medium term primary patency rates are excellent, but careful follow-up is needed to determine the durability of these techniques.

Endovascular Chimney Technique for Juxtarenal Abdominal Aortic Aneurysm: A Systematic Review Using Pooled Analysis and Meta-Analysis

“…Of these 20 endoleaks, 12 type I endoleaks were considered as ''low flows,'' which appeared after some delay 26 and finally disappeared during follow-up. 1,14,18,21,24 The ''kissing balloon'' technique, 13 Palmaz stent (Cordis, Miami Lakes, FL), 1 proximal coil embolization or extender cuff placement 18,20 were successfully used to resolve the other 8 type I endoleaks (Table IV). A total of 13 patients (5.5%) developed type II endoleaks within 30 days without death.…”

Chimney Technique in the Endovascular Repair of Juxtarenal Abdominal Aortic Aneurysm

“…In 2007, Hiramoto et al published their experience with 29 patients in which 31 renal stents were placed [ 11 ] . Of their 29 patients, 18 had planned stenting for proximal neck length of <15 mm, and the other 11 were unplanned events.…”

A Case of Near Total Occlusion of the Renal Artery after Endovascular Abdominal Aortic Aneurysm Repair

“…First, the patient's blood pressure rose slowly over a long period of time after the initial EVAR procedure and was found by laboratory tests aortic aneurysm repair is effective and safe. 6 Thus, if the occlusion is confirmed during EVAR, adjunctive stenting will prevent the need to undergo a second medical procedure.…”