Intravascular ultrasound evidence for stabilization of compensatory enlargement of the femoropopliteal segment after endograft placement

Purpose: To document whether the vasodilatory response seen at the anastomo tic segment 6 months after placement of a balloon-expandable endograft in t he femoropopliteal segment progresses between 6 and 24 months. Methods: Twelve patients (9 men; median age 65 years, range 47-75) treated with an investigational polytetrafluoroethylene (PTFE) endograft for obstru ctive disease of the femoropopliteal segment were studied with intravascula r ultrasound (IVUS) immediately after placement and at 6 months (first foll ow-up period) and 24 months (second follow-up period). Matched IVUS cross s ections derived from the endograft and the anastomotic segment were analyze d for changes in lumen (LA), vessel (VA), and plaque areas (PLA). Results: Five patients had complete IVUS surveillance at both the first (me an 8 months, range 7-9) and second (mean 25 months, range 23-26) follow-up periods; 1 patient was lost to follow-up during the second interval, and an other 6 were excluded owing to graft occlusion (n = 4) or no IVUS surveilla nce available (n = 2) during the second follow-up period. Matched IVUS cros s sections derived from the endograft showed no significant change in LA du ring both follow-up periods (-8% and +1%, respectively). There was no evide nce for intimal hyperplasia or endograft recoil. During both follow-up peri ods, IVUS cross sections derived from the anastomotic segment revealed sign ificant increases in LA (+37% and +8%, respectively) and VA (+26% and +6%, respectively) (both p < 0.05). The change in PLA during both follow-up peri ods was not significant (+13% and +3%, respectively). Conclusions: The PTFE endograft seems to inhibit both intimal hyperplasia a nd constrictive remodeling. The short-term (6-month) vascular dilatory resp onse seen at the anastomotic segment tends to stabilize at 2 years. Therefo re, this endovascular anastomosis acts as an "ideal" end-to-end anastomosis .