Impact of kidney ischemic lesions on renal function after fenestrated endovascular repair

Fenestrated endovascular aortic repair (fEVAR) is being used increasingly in the treatment of complex aortic aneurysms; however, this procedure can be associated with visceral and renal complications. Because the causes of possible renal function (RF) impairment have not been fully examined yet, we conducted a study to investigate whether there are risk factors associate with renal ischemic lesions (RILs) and if they influence RF in patients treated for complex aortic aneurysm with fEVAR.

We evaluated the clinical, anatomic, and technical characteristics of consecutive patients treated with fEVAR from 2008 to 2014. RIL were identified by postoperative computed tomography angiography and the volume of renal parenchyma involved quantified. A decrease in RF (>30% glomerular filtration rate reduction) was evaluated at discharge, and at the 6- and 12-month follow-ups.

Among 53 patients, we analyzed 38 (72%) juxta/pararenal and 15 (28%) thoracoabdominal aortic aneurysms (33 [64%] with ≥3 fenestrations) and 102 renal arteries. Fifteen patients (30%) showed RIL, which was caused by accessory renal artery (ARA) coverage in 6 cases (38%), distal embolism in 6 (38%), renal artery thrombosis in 2 (18%), and iatrogenic embolization for intraoperative bleeding during fEVAR in 1 (6%). The volume of renal parenchyma involved was less than 25% in 10 (67%) and 25% to 50% in 5 (33%) cases. In no cases was more than 50% renal volume affected. On multivariate analysis, RIL predictors were the presence of ARA (odds ratio [OR], 8.00; 95% confidence interval [CI], 1.16-54.89; P = .03) and extensive thrombosis of the pararenal aorta (OR, 39.93; 95% CI, 3.36-474.23; P = .003). At discharge, chronic renal failure (CRF; OR, 4.80; 95% CI, 1.27-18.09; P = .01), diabetes (OR, 8.44; 95% CI, 1.33-53.51; P = .01), and extensive thrombosis of the pararenal aorta (OR, 5.50; 95% CI, 1.32-29.92; P = .01) were significantly associated with worsening RF. RIL, independent from volume, did not influence the postoperative RF. At 6 months and 1-year, preoperative CRF and perioperative declines in RF were identified as the only risk factors for worsening RF.

RIL is a common fEVAR complication and is primarily owing to ARA coverage and aortic thrombus embolization. However, RIL does not influence RF, which is predicted by preoperative CRF, diabetes, and extensive aortic thrombus.