Endovascular management of cerebral bypass graft problems: an analysis of technique and results

Abstract

Background and purpose: Cerebral bypass grafts may develop generalized graft narrowing or focal stenosis during the perioperative period or later. Endovascular techniques such as PTA and stent placement of graft vessels are potential treatment options. Our objective was to review the safety, indications, technique, and results of endovascular management of graft problems.

Materials and methods: All patients with cerebral bypass procedures by using graft vessels from 2005 to 2009 were identified from a prospective registry and were studied retrospectively. Patient characteristics, bypass procedures, indications for endovascular interventions, graft patency, and clinical outcomes were reviewed from medical charts and imaging records.

Results: A total of 79 patients underwent bypass procedures by using graft vessels. Seven patients of this group underwent endovascular interventions for the treatment of graft narrowing. Four of the 7 patients were treated for graft narrowing in the perioperative period (<1 month) with PTA; and 3 of the 7 patients, for late stenosis, 2 with PTA alone and 1 with PTA followed by stent placement. All procedures were immediately successful in improving flow through the graft. In late stenosis, PTA alone provided temporary improvement followed by recurrence, whereas PTA with a stent procedure was effective in the 1 patient long term.

Conclusions: PTA is safe and effective in the management of graft spasm in the perioperative period. For late graft stenosis, PTA alone provides only temporary respite, while PTA with stent placement may be an effective solution.

Fig 1.

A, Postoperative angiogram (IADSA), lateral view right ICA injection, shows the IC-IC bypass from the MCA to the PCA. B, Angiogram (IADSA), right ICA anteroposterior view, with the catheter showing poor graft filling before the angioplasty procedure. C, Angiogram shows the balloon catheter (arrow) positioned in the graft across the segment of narrowing in the proximal graft. D, Post-PTA IADSA showing much better graft flow (arrow). Distal segments of the graft show narrowing.

Fig 2.

A, Angiogram (IADSA), ICA anteroposterior view, status postclipping of a giant MCA aneurysm shows the stenotic MCA branches—superior and inferior. B, Angiographic 3D reconstruction shows the RAG bypass on the left side from the ECA to the MCA M2, immediately postsurgery. C, Angiogram (IADSA), ICA injection, anteroposterior view, 8 months postoperatively, shows the poor flow in the graft with a stenosis in the proximal fourth of the graft (arrow). D, Angiogram, lateral view left common carotid injection, shows the HyperGlide balloon catheter (arrow) with the Envoy catheter in the graft vessel. E, Angiogram (IADSA), ICA injection, anteroposterior oblique view, immediately after angioplasty and stent placement (arrow), shows good filling of the bypass graft. F, Angiogram (IADSA), common carotid anteroposterior oblique view 3 months after angioplasty and stent placement, with the arrow showing the stent in place and a much-improved flow.