Percutaneous treatment of symptomatic vertebral artery stenosis with coronary stents

Distal Embolization After Stenting of the Vertebral Artery: Diffusion-Weighted Magnetic Resonance Imaging Findings

PURPOSE

We retrospectively evaluated our experience with stenting of the vertebral artery in an effort to determine the risk of distal embolization associated with the procedure.

METHODS

Between June 2000 and May 2005, 35 patients with 38 stenting procedures for atherosclerotic disease of the vertebral origin in our institution were identified. The average age of the patients was 60.3 years (range 32-76 years). Sixteen of these patients (with 18 stents) had MR imaging of the brain with diffusion-weighted imaging and an apparent diffusion coefficient map within 2 days before and after procedure.

RESULTS

On seven of the 16 postprocedural diffusion-weighted MR images, a total of 57 new hyperintensities were visible. All these lesions were focal in nature. One patient demonstrated a new diffusion-weighted imaging abnormality in the anterior circulation without MR evidence of posterior circulation ischemia. Six of 16 patients had a total of 25 new lesions in the vertebrobasilar circulation in postprocedural diffusion-weighted MR images. One patient in this group was excluded from the final analysis because the procedure was complicated by basilar rupture during tandem stent deployment in the basilar artery. Hence, new diffusion-weighted imaging abnormalities were noted in the vertebrobasilar territory in 5 of 15 patients after 17 stenting procedures, giving a 29% rate of diffusion-weighted imaging abnormalities per procedure. No patient with bilateral stenting had new diffusion-weighted imaging abnormalities.

CONCLUSION

Stenting of stenoses of the vertebral artery origin may be associated with a significant risk of asymptomatic distal embolization. Angiography, placement of the guiding catheter, inflation of the stent balloon, and crossing the lesion with guidewires or balloon catheters may potentially cause distal embolization. Further studies to evaluate measures to increase the safety of vertebral artery stenting, such as the use of distal protection devices or short-term postprocedural anticoagulation, should be considered for patients with clear indications for this procedure.

Symptomatic non-atherosclerotic bilateral extracranial vertebral artery occlusion treated with extracranial to intracranial bypass: case report

Posterior fossa ischemia is not a very frequent situation. It is responsible for about 25% of all ischemic strokes, and the vast majority of the cases are related to atherosclerotic stenosis of the vertebral and/or basilar arteries. Acute ischemia can also occur in the setting of vertebral artery dissection, traumatic or spontaneous. Recently, blunt trauma has been increasingly recognized as a cause for craniocervical artery injury. The management options for both traumatic and atherosclerotic lesions of the posterior fossa are still under debate. We present a case of a delayed onset of hemodynamic ischemic symptoms due to bilateral vertebral artery occlusion probably related to remote trauma to the head and neck in a 55-year-old-man treated successfully with extracranial to intracranial bypass.

Management of Vertebral Stenosis Complicated by Presence of Acute Thrombus

A 44-year-old male presented with multiple punctate acute infarcts of the vertebrobasilar circulation and a computed tomographic angiogram showing stenosis of the right vertebral origin. A digital subtraction angiogram demonstrated a new intraluminal filling defect at the origin of the stenotic vertebral artery where antegrade flow was maintained. This filling defect was accepted to be an acute thrombus of the vertebral origin, most likely due to rupture of a vulnerable plaque. The patient was treated with intravenous heparin. A control angiogram revealed dissolution of the acute thrombus under anticoagulation and the patient was treated with stenting with distal protection. Diffusion-weighted magnetic resonance imaging demonstrated no additional acute ischemic lesions. We were unable to find a similar report in the English literature documenting successful management of an acute vertebral ostial thrombus with anticoagulation. Anticoagulation might be considered prior to endovascular treatment of symptomatic vertebral stenoses complicated by the presence of acute thrombus.