Impact on renal function after endovascular aneurysm repair with uncovered supra-renal fixation assessed by serum cystatin C.

Objective: Supra-renal fixation in endovascular aneurysm repair (SR-EVR) is used to improve the proximal seal of aortic stent grafts and appears to have minimal effect on serum creatinine. Serum cystatin C (CC) is a more sensitive marker of renal injury and, unlike creatinine, is unaffected by non-renal influence. The aim of this study was to assess the true renal effect of SR-EVR using this superior renal index.

Methods: Consecutive patients undergoing SR-EVR were prospectively recruited and compared to control groups undergoing open aneurysm repair (OR) and colorectal resection (CR). Serum CC and creatinine clearance (CrC) were determined pre-operatively and at 3, 6 and 12 months post-surgery. Renal function was compared using analyses of covariance (ANCOVA).

Results: Sixty-five patients (M:F; 52:13, median age 74 years) were enrolled (24 SR-EVR, 28 OR, 13 CR). Pre-operative renal function and risk factors were comparable (CC 1.04mg/l, SR-EVR; 0.96mg/l, OR; 0.97mg/l, CR). Adjusting for baseline renal function, there was no significant difference in CC or CrC between study and both control groups at 3, 6 or 12-months post-operatively.

Conclusion: Using cystatin C as a more sensitive renal index, there was no detectable evidence of kidney dysfunction at up to one-year following EVR with uncovered bare-metal supra-renal fixation.