Prediction of Renal Function Decline After Endovascular Aortic Repair Using Three-Dimensional Image Analysis

Some accessory renal arteries (ARA) branching from the necks or abdominal aortic aneurysms (AAAs) need to be sacrificed at endovascular aortic repair (EVAR). Precise prediction of the effect of ARA interruption on renal function is challenging but helpful especially in cases with renal dysfunction. We aimed to predict renal function decline using a three-dimensional (3D) image analyzer. Consecutive patients undergoing EVAR for AAAs between January 2020 and June 2023 were included. Patients on dialysis were excluded. They were classified into three groups: no ARA, preserved ARA, and sacrificed ARA groups. Changes in estimated glomerular filtration rate (eGFR) were compared in each group. Volume of ARA perfusion area (Va) was simulated, and those of postoperative ischemic area (Vi) and whole kidneys (Vt) were calculated using a 3D image analyzer (SYNAPSE VINCENT; Fujifilm) on contrast enhanced computed tomography imaging (Fig). Predicted eGFR was calculated as preoperative eGFR × (1 – Va/Vt). Predictability of postoperative eGFR was compared between 3D imaging-based and diameter-based prediction based on correlation coefficient. Other variables such as blood loss and dose of contrast medium were also analyzed. ARAs existed in 42 cases (38%), and 8 cases (19%) required interruption of ARAs. The size of ARA was 2.38 ± 0.46 mm in diameter. Decline in eGFR after EVAR was 0 (−5.5 to 11.3) mL/min/1.73 m2 in the no ARA group, –1.8 (–5.6 to 2.0) mL/min/1.73 m2 in the preserved ARA group, and –12.8 (–21.4 to 5.4) mL/min/1.73 m2 in the sacrificed ARA group. Significant decline in eGFR was observed in the sacrificed eGFR group (P = .036). Vt was 234.5 ± 38.4 mL, Va was 17.6 ± 8.3 mL, and Vi was 15.6 ± 6.6 mL. Strong correlation was observed between Va and Vi (r = 0.87, P = .01) and between 3D imaging-based predicted eGFR and actual postoperative eGFR (r = 0.91, P < .01). On the other hand, the correlation between the eGFR decline and ARA diameter was weak (r = 0.13, P = .77). Blood loss and dose of contrast medium also did not offer any precise prediction (r = –0.52 to 0.027, P > .05 for all). Sacrifice of ARAs at EVAR decreases renal function. 3D imaging volumetry rather than ARA diameter enables precise prediction on postoperative eGFR, and thus can offer essential information on determining the surgical options in patients with ARAs.