Differential effects of stent-graft fabrics on arterial stiffness in patients undergoing endovascular aneurysm repair.

PURPOSE: To evaluate the differential effects of endograft fabric types on pulse wave velocity (PWV), a valid, clinically feasible marker of arterial stiffness, in patients undergoing endovascular repair (EVAR) of abdominal aortic aneurysms (AAAs).

METHODS

As part of a registered study (ClinicalTrials.gov identifier NCT00636766), 118 consecutive men (mean age 71 ± 8 years) with AAA undergoing elective EVAR were divided into groups according to the type of fabric in the implanted endografts: 46 had polytetrafluoroethylene (PTFE)-covered stent-grafts and 72 received stent-grafts covered with polyester fabric. Patients with Marfan syndrome, collagen-related disorders, and end-stage renal failure were excluded. PWV, clinical characteristics (comorbidities, body mass index, blood pressure, lipids, and glucose profile), novel biomarkers [interleukin (IL)-6, IL-8, IL-10, and osteoprotegerin (OPG)] were determined at baseline and prospectively after 12 months.

RESULTS

At baseline, standard multiple regression analysis revealed the independent association of mean blood pressure, OPG, and AAA diameter with PWV after adjustment for age (R(2)=0.729, p=0.036). At follow-up, serum levels of both IL-8 and IL-10 were significantly increased, while OPG decreased in both groups (p<0.05). However, between-group comparison revealed a more adverse effect of polyester covered endografts on serum IL-8 (p<0.001) and OPG (p=0.048) levels. At the same time, PWV was considerably increased in both polyester (+4.12±0.33 m/s, p<0.001) and PTFE (+2.82 ± 0.25 m/s, p=0.003) groups; the effect was more pronounced in the former group (p=0.033). In multivariate analysis, the polyester endograft type emerged as an independent determinant of PWV change after EVAR (R(2)=0.460, p=0.040).

CONCLUSION

Both endograft types increased PWV, while recipients of polyester covered stent-grafts showed greater PWV elevation. Further investigation will clarify the inflammatory response and the differential clinical impact of endograft types.