Renal Artery Reimplantation Versus Bypass in Elective Open Aneurysm Repair

Background: Complex open abdominal aortic aneurysm (AAA) repair often necessitates revascularization of renal arteries by either renal artery reimplantation or bypass. This study aims to evaluate the perioperative and short term outcomes between these 2 strategies of renal artery revascularization.Methods: We performed a retrospective review of patients who underwent open AAA repair from 2004 to 2020 at our own institution. Patients who underwent elective suprarenal, juxtarenal, or type 4 thoracoabdominal aneurysm repair were identified using current procedural terminol-ogy (CPT) codes and a retrospectively maintained database of AAA patients. Patients who had symptomatic aneurysm or significant renal artery stenosis before AAA repair were excluded. Patient demographics, intraoperative conditions, renal function, bypass patency, and perioper-ative and postoperative outcomes at 30 days and 1 year were compared.Results: One hundred and forty-three patients underwent either renal artery reimplantation (n = 86) or bypass (n = 57) during this time period. The mean age was 69.7 years and 76.2% of the patients were male. Median preoperative creatinine was 1.2 mg/dL for the renal bypass group versus 1.06 mg/dL for reimplantation (P = 0.088). Both groups had similar me-dian preoperative glomerular filtration rate (GFR) of >60 mL/min (P = 0.13). Bypass and reimplantation groups had similar perioperative complications including acute kidney injury (51.8% vs. 49.4% P = 0.78), inpatient dialysis (3.6% vs. 1.2% P = 0.56), myocardial infarction (1.8% vs. 2.4% P = 0.99), and death (3.5% vs. 4.7% P = 0.99), respectively. During the 30-day follow-up period, renal artery stenosis was identified in 9.8% of bypasses and 6.7% of reimplantations (P = 0.71). Six point one percent of patients in the bypass group had renal failure requiring dialysis (both acute and permanent) compared to 1.3% in reim-plantation group (P = 0.3). For those who had 1-year follow-up, the reimplantation group had higher new incidence of renal artery stenosis compared to bypass group (6 vs. 0 P = 0.16).Conclusions: Given that there is no significant difference in outcomes between renal artery reimplantation and bypass within 30 days or at 1-year follow-up, both bypass and reimplantation are acceptable means for renal artery revascularization during elective AAA repair.