Use of Abdominal Chimney Grafts is Feasible and Safe: Short-term Results

Purpose: To present our initial experience with the use of chimney grafts in endovascular aneurysm repair (EVAR) of abdominal aortic aneurysms (AAAs) with challenging anatomy.Methods: Among 390 EVAR cases performed at our institution between November 2008 and February 2010, 15 patients (all men; mean age 81.8 years) underwent EVAR with synchronous placement of chimney grafts. The chimney technique involved placing covered stents parallel to the main aortic stent-graft to preserve or rescue flow to aortic branch vessels while extending the proximal fixation zone. All patients presented with pararenal aortic aneurysms with short necks (between 0 and 10 mm long) that required either suprarenal clamping to tailor a proximal anastomosis in open repair or suprarenal fixation to anchor an endoprosthesis. Chimney grafts were implanted into 10 left renal and 5 right renal arteries.Results: The immediate technical success was 100%. One early type II endoleak due to retrograde flow from the inferior mesenteric artery was detected and is under surveillance. Mean follow-up was 6.8 months (range 1–13). One chimney graft occluded 45 days postoperatively; the patient underwent open thrombectomy of the left renal artery and iliorenal bypass. The creatinine value at discharge was 1.6 mg/dL, and resting renal scintigraphy showed 36% perfusion for the left kidney and 64% for the right kidney. During follow-up, no patient required hemodialysis; no aneurysm-related deaths were noted.Conclusion: This limited experience demonstrates that the use of abdominal chimney grafts is feasible and safe. Long-term results in larger patient cohorts are needed evaluate the utility of this alternative endovascular technique.