Preliminary experience with optical coherence tomography imaging to evaluate carotid artery stents: safety, feasibility and techniques

Abstract

Optical coherence tomography (OCT) is an increasingly used intravascular imaging modality to assess coronary stent implantation and vessel healing. A recently developed catheter (C7 Dragonfly; LightLab Imaging Inc.,Westford, MA, USA) allows visualisation of peripheral arteries up to 10 mm of diameter with high speed pullback. Safety, feasibility and the technique of OCT following carotid artery stenting (CAS) were evaluated in the present study. OCT was performed in seven consecutive patients following successful CAS using proximal cerebral protection devices, occluding the common and external carotid artery and gentle manual injection of a total of 8-14 ml of 50% diluted contrast media with normal saline in order to displace the blood from the artery. Once the blood was displaced, pullback was started through the stented segment continuing the gentle contrast injection. After completion of the pullback all injected contrast was aspirated and discarded. In the first three patients, OCT was also performed without internal carotid artery flow blockage. Due to the high blood flow in the ICA it was not possible to replace all residual blood and obtain adequate OCT images. No procedural, in-hospital, or 30-day follow-up complications occurred. One patient experienced transient intolerance to vessel occlusion without any neurological sequels. OCT images were of good quality providing important information regarding stent geometry, presence and lack of strut apposition, plaque fracture, and plaque prolapse. Intravascular OCT under occlusive proximal protection appears feasible and safe to assess stent implantation in carotid arteries.