Hungarian Radiology

[Forces exerted on the plaques during in vitro measurements by various carotid stent delivery systems and embolic protection devices]


SEPTEMBER 20, 2008

Hungarian Radiology - 2008;82(05-06)

[PURPOSE - During the endovascular treatment of internal carotid artery stenosis, one of the most important aspects is reducing of embolic complications. Degree of embolization may be influenced by the force exerted by stent delivery systems and embolic protection devices. We assessed the force emersion produced by various devices on vessel walls and plaques. MATERIAL AND METHOD - Six different commercially available devices were investigated. The force load on vessel wall was measured in a carotid model with vessel angulations of 25, 50 and 75 degree, respectively. The IDTE 2000 CE marked measurement system was used. A transparent, flexible PVC tube was used as a model of the carotid bifurcation, which was 6 mm in width, 1.5 mm wall thickness and 12 mm length. 75-85% stenosis were created in it. The measured data were evaluated and different conclusions were drawn. RESULTS - Forces exerted on vessel walls varied widely among different stent delivery systems. The magnitude of force exertion caused by stent delivery systems significantly exceeded that caused by protecting devices. Protecting devices showed only 30% increase in vessel load at angulation of 75 degrees compared to those at 25-50 degrees. Above 50 degrees of vessel angulation the forces exerted by stent delivery systems considerably increases. CONCLUSIONS - Our results showed that selection of the most proper stent can contribute to decrease in the load of vessel wall. Protecting devices exert significantly lower forces than stent delivery systems, therefore, it seems to be a better choice to advance a protecting device before introducing a stent delivery system. If the vessel angulation exceeds 50 degrees, endarterectomy should be considered, because the vessel wall load will increase radically in that case.]



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