The Impact of Stent Graft Material on the Inflammatory Response After EVAR

Patients undergoing endovascular aneurysm repair (EVAR) due to abdominal aortic aneurysm often develop an inflammatory response, postimplantation syndrome (PIS) where fever and leukocytosis are common. Previous studies suggest that type of stent graft material (polyester or polytetrafluoroethylene [PTFE]) plays a role.

To investigate the effect of stent graft material on the inflammatory response and length of hospital stay in patients undergoing standard elective EVAR.

Sixty-nine elective EVAR patients were included in this observational study. To avoid comparing patients with a different graft location and stent graft burden, 12 cases were excluded as well as cases with complication or simultaneous open surgical procedures, leaving 45 patients (32 with polyester and 13 with PTFE graft) for final analysis. Tympanic temperature, C-reactive protein (CRP), white blood cell (WBC), and procalcitonin (PCT) were measured on days -1 and +1 and +3. Duration of in-hospital stay and frequency of PIS were recorded.

The PIS was diagnosed in 9 (28.1%) of the 32 polyester cases and in 1 (7.7%) of the 13 cases in the PTFE group (P = .24). Median (interquartile range) in-hospital stay was 5 (5-6) days in the polyester group and 4 (4-5) days in the PTFE group (P = .009). On day +3, in the polyester group, mean CRP was 154 (95% confidence interval: 127-182) mg/L, WBC 9.5 (8.4-10.5) ×10(9)/L, and PCT 0.17 (0.12-0.21) ng/mL. In the PTFE group, mean CRP was 70 (32-109) mg/L (P = .001), WBC 8.8 (6.4-11.1) ×10(9)/L (P = .37), and PCT 0.09 (0.06-0.13) ng/mL (P = .009) on day +3.

Standard EVAR with polyester stent grafts appears to result in a trend toward a more pronounced inflammatory reaction than similar EVAR using PTFE and is associated with a longer in-hospital stay.