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.
Keywords: abdominal aortic aneurysm; biomarkers; endograft; endovascular aneurysm repair; interleukins; osteoprotegerin; polyester fabric; polytetrafluoroethylene fabric; pulse wave velocity; stent-graft.