Treatment for Bilateral Vertebral Artery Occlusion
The treatment for bilateral vertebral artery occlusion should include antiplatelet therapy with aspirin (75-325 mg daily) as first-line therapy, with anticoagulation for at least 3 months if there is angiographic evidence of thrombus in the extracranial portion of the vertebral artery. 1, 2
Diagnostic Approach
- MRA or CTA is recommended over ultrasound for evaluation of vertebral arteries in patients with suspected posterior cerebral or cerebellar ischemia due to higher diagnostic accuracy (94% vs 70% sensitivity) 1, 3
- Catheter-based contrast angiography is useful when noninvasive imaging fails to define the location or severity of stenosis in patients who may be candidates for revascularization 3, 1
- Serial noninvasive imaging of the extracranial vertebral arteries is reasonable to assess progression of atherosclerotic disease and exclude development of new lesions 3, 2
Medical Management
First-Line Therapy
- Antiplatelet therapy is the cornerstone of management 3, 2:
- Aspirin (75-325 mg daily) is the first-line therapy 3, 1
- For patients with aspirin contraindications, clopidogrel (75 mg daily) or ticlopidine (250 mg twice daily) are reasonable alternatives 3, 2
- The combination of aspirin plus extended-release dipyridamole has shown benefit in reducing vertebrobasilar territory stroke or TIA compared to placebo 1, 3
Anticoagulation
- For patients with acute ischemic syndromes involving the vertebral artery territory with angiographic evidence of thrombus in the extracranial portion, anticoagulation is recommended for at least 3 months, whether or not thrombolytic therapy is used initially 1, 3
- The WASID trial found aspirin and warfarin to be equally efficacious after initial noncardioembolic ischemic stroke 3
Risk Factor Management
- Medical therapy and lifestyle modification to reduce atherosclerotic risk are recommended according to the standards for extracranial carotid atherosclerosis 3
Revascularization Options
Revascularization should be considered when medical therapy fails to control symptoms 2. The approach depends on the location and severity of occlusion:
Surgical Options
- Surgical approaches for proximal vertebral artery reconstruction include 3, 1:
- Trans-subclavian vertebral endarterectomy
- Transposition of the vertebral artery to the ipsilateral common carotid artery
- Reimplantation of the vertebral artery with vein graft extension to the subclavian artery
- Early complication rates for proximal vertebral artery reconstruction range from 2.5% to 25% with perioperative mortality rates of 0% to 4% 1, 4
- For distal vertebral artery reconstruction, mortality rates range from 2% to 8% 3
Endovascular Treatment
- Endovascular treatment (angioplasty and stenting) carries risks 3, 2:
- Death (0.3%)
- Periprocedural neurological complications (5.5%)
- Posterior stroke (0.7%)
- Restenosis occurs in approximately 26% of proximal vertebral artery interventions 1, 2
- Rates of stroke and restenosis appear to be related to ascending (more distal) location and anatomic complexity of the lesion 3
Special Considerations
- For subclavian steal syndrome, extra-anatomic carotid-subclavian bypass is recommended in the absence of clinical factors predisposing to surgical morbidity 3, 2
- Percutaneous endovascular angioplasty and stenting is reasonable for patients with symptomatic posterior cerebral or cerebellar ischemia caused by subclavian artery stenosis who are at high risk of surgical complications 3
- Bilateral distal vertebral artery occlusion has historically been associated with poor outcomes, with mortality rates of 4.5% per year and stroke rates of 1.8% per year in long-term follow-up 5
- Patients with bilateral distal vertebral artery occlusion may present with progressive or stepwise neurologic deficits over a longer time period than those with basilar artery occlusion 6