Treatment for Vertebral Artery Occlusion
Medical management with antiplatelet therapy is the first-line treatment for vertebral artery occlusion, with anticoagulation reserved for acute presentations with angiographic evidence of thrombus, and revascularization considered only after medical therapy fails in patients with recurrent posterior circulation ischemic symptoms. 1
Acute Presentation Management
For acute ischemic stroke from vertebral artery occlusion, mechanical thrombectomy should be performed within 12 hours if NIHSS ≥6, PC-ASPECTS ≥6, and age 18-89 years, with reasonable benefit extending to 24 hours using the same criteria. 1 Recanalization of the occluded vessel significantly improves morbidity and mortality outcomes. 2
When angiographic evidence of thrombus exists in the extracranial vertebral artery, initiate anticoagulation with intravenous heparin followed by oral warfarin for at least 3 months, regardless of whether thrombolytic therapy is used. 3, 1 This applies to both atherosclerotic occlusions and traumatic dissections. 4
Initial Diagnostic Evaluation
Obtain MRA or CTA rather than ultrasound for initial evaluation, as these modalities demonstrate 94% sensitivity versus only 70% for ultrasound. 1, 4 However, neither MRA nor CTA reliably delineates vertebral artery origins. 3, 1
Catheter-based contrast angiography is mandatory before any revascularization procedure. 3, 1 For suspected rotational vertebral artery occlusion, dynamic angiography with progressive head rotation is essential to identify the correct site of compression, most commonly at the C2 level. 5
Medical Therapy for Chronic Management
Aspirin 75-325 mg daily is first-line antiplatelet therapy for vertebral artery occlusion. 1 The evidence supporting this approach comes from multiple guideline recommendations. 3
The combination of aspirin plus extended-release dipyridamole 200 mg twice daily is superior to aspirin alone, reducing vertebrobasilar territory stroke/TIA from 10.8% to 5.7% compared to placebo. 3, 1 This represents the strongest evidence for dual antiplatelet therapy in this population.
Ticlopidine 250 mg twice daily demonstrated superiority over aspirin for secondary prevention in symptomatic posterior circulation disease, though it is less commonly used due to side effect profile. 3, 1
Critical Pitfall to Avoid
Do not use dual antiplatelet therapy with aspirin plus clopidogrel routinely, as hemorrhage risk outweighs benefit. 1 This differs from the aspirin-dipyridamole combination, which has proven efficacy.
Indications for Revascularization
Revascularization should only be pursued after medical therapy fails in patients with persistent or recurrent posterior circulation ischemic symptoms despite optimal medical management. 1 There is insufficient evidence from randomized trials demonstrating that endovascular or surgical management is superior to best medical management. 3
The decision for intervention must account for anatomic considerations: when both vertebral arteries are patent and one has significant stenosis, the contralateral vertebral artery usually supplies sufficient blood flow to the basilar artery if it is the dominant vessel. 3 However, atheroembolism from vertebral artery origin lesions may cause brainstem or cerebellar infarction even with a patent contralateral vessel. 1
Endovascular Treatment
Endovascular treatment with angioplasty and stenting carries a 0.3% death risk, 5.5% periprocedural neurological complication risk, and 0.7% posterior stroke risk at 14.2 months follow-up. 1 These risks must be weighed against the natural history of medically-managed disease.
Restenosis occurs in 26% of proximal vertebral artery interventions at mean 12-month follow-up, though this is not consistently correlated with recurrent symptoms. 3, 1 For distal vertebrobasilar disease, neurological complications develop in 24% of cases, approaching 80% in urgent revascularization scenarios. 3
Staged endovascular treatment may be considered for symptomatic intracranial vertebral artery occlusion in the early non-acute stage (4-21 days from onset) when aggressive ischemic events occur despite medical therapy, though this approach requires further validation in controlled studies. 6
Surgical Treatment
Surgical approaches include trans-subclavian vertebral endarterectomy, transposition of the vertebral artery to the ipsilateral common carotid artery, and reimplantation with vein graft extension to the subclavian artery. 3, 1
For proximal vertebral artery reconstruction, early complication rates range from 2.5% to 25% with perioperative mortality of 0% to 4%. 3, 1 For distal vertebral artery reconstruction, mortality rates range from 2% to 8%. 3 Intracranial bypass surgery carries mortality rates of 3% to 12% and neurological/systemic complication rates of 22% to 55%. 3
Surgical decompression is indicated for rotational vertebral artery occlusion caused by extrinsic compression (such as cervical osteophytes) when conservative management fails. 7, 5 Dynamic angiography must identify the precise site of occlusion to guide surgical planning, as misdiagnosis or missing a second occlusive site can lead to treatment failure. 5
Long-Term Management
Continue indefinite antiplatelet therapy after the acute phase with aggressive cardiovascular risk factor modification including lipid management, blood pressure control, and smoking cessation. 1, 4
Serial noninvasive imaging of the extracranial vertebral arteries at intervals similar to those for carotid revascularization is reasonable to assess disease progression and exclude new lesions. 1 Monitor continuously for recurrent symptoms given the 25% mortality rate reported in vertebral artery occlusion series, with higher risk in distal segmental and extensive occlusions. 8