FEVAR branches can occlude jeopardizing perfusion of the organs they supply. A recent study has shown the rate of patency as 95.7% at 1 year and 88.6% at 4 years. Pooled analysis has shown a 4.5% rate of renal artery occlusion during 12 month follow up with 2.3% going on to dialysis and 1.4% requiring permanent dialysis. 1.8% of patients can go on to have mesenteric stenosis though these have been due to technical issues with the stents.