Effect of abdominal aortic grafts on aortic stiffness and central hemodynamics

Graft-prosthesis and stentgraft placements are effective modalities for treating abdominal aortic aneurysm, but related changes in arterial stiffness are not well established. The present study sought to assess aortic stiffness after aneurism repair by measuring pulse wave velocity (PWV). The graft-related variation of carotid-femoral PWV was compared with that of carotid-radial PWV, the latter being unaffected by vascular treatment. The secondary objective was to evaluate potential differences between graft-prosthesis and stentgraft in terms of aortic stiffness and augmentation index, a composite indicator integrating wave reflexion. Fifty patients were included (39 had a graft-prosthesis and 11 had a stentgraft). In the whole group and after a median postoperative follow-up of 47 days, carotid-femoral PWV increased by +1.0 m/s [-12.3, +10.3], while carotid-radial PWV slightly decreased by -0.3 m/s [-4.4; +3.5] (P = 0.001). The effect of the type of prosthesis on the PWV was not significant. Nevertheless, the augmentation index increased after stentgraft implantation (+4% [-10; +17]) and decreased after graft-prosthesis placement (-8.5% [-47; +17]) (P<0.01). This difference was not explained by a heart rate or a treatment effect and was likely attributable to the prosthesis per se. This study demonstrates the impact of aortic grafts on aortic stiffness. Besides, it suggests that stentgraft increases reflected waves more than graft-prostheses. These changes of vascular properties may influence the outcomes after surgery.© 2009 Wolters Kluwer Health.