Current PTFE grafts: a biomechanical, scanning electron, and light microscopic evaluation

Area of Science:

• Biomaterials Science
• Vascular Surgery
• Histology

Background:

• Polytetrafluoroethylene (PTFE) grafts are commonly used in vascular reconstructions.
• Recent manufacturing changes aimed to increase the strength of PTFE grafts.
• The impact of these modifications on graft performance and biological response requires investigation.

Purpose of the Study:

• To evaluate the biophysical properties and histological reactivity of two modified PTFE graft brands (Goretex and Impra).
• To assess the suitability of a canine femoral artery model for testing small to medium diameter arterial prostheses.

Main Methods:

• Comparative study of Goretex and Impra PTFE grafts implanted in a canine femoral artery model.
• Assessment of in vivo dynamic compliance.
• Histological analysis using scanning electron microscopy (SEM) and light microscopy.

Main Results:

• Both PTFE graft brands exhibited nearly identical in vivo dynamic compliances.
• SEM revealed endothelialization primarily adjacent to the anastomoses.
• Light microscopy showed similar degrees of host tissue incorporation for both grafts, albeit at a slower rate than previously reported.

Conclusions:

• Manufacturing modifications to increase PTFE graft strength did not significantly alter their biophysical properties or histological reactivity in this model.
• The canine femoral artery model appears suitable for characterizing new small to medium diameter arterial prostheses.