Use of abdominal chimney grafts is feasible and safe: short-term results

To present our initial experience with the use of chimney grafts in endovascular aneurysm repair (EVAR) of abdominal aortic aneurysms (AAAs) with challenging anatomy.

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.

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.

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.