What is the treatment protocol for vertebral artery (VA) occlusion, stenosis, dissection, or pseudoaneurysm due to trauma, including medications and duration?

Treatment Protocol for Traumatic Vertebral Artery Injury

Initial Medical Management

For traumatic vertebral artery dissection, occlusion, stenosis, or pseudoaneurysm with angiographic evidence of thrombus in the extracranial portion, initiate anticoagulation with intravenous heparin followed by oral warfarin for at least 3 months. 1, 2

Anticoagulation Protocol (First-Line for Thrombus Present)

• Start: Intravenous heparin immediately upon diagnosis 1
• Transition: Convert to oral warfarin (Coumadin) after initial stabilization 1
• Duration: Minimum 3 months of anticoagulation therapy 1, 2
• Monitoring: This applies whether or not thrombolytic therapy is used initially 1

Antiplatelet Therapy (Alternative or for No Thrombus)

For patients without angiographic evidence of thrombus, or after completing 3 months of anticoagulation, transition to antiplatelet therapy. 1, 2

Medication Options (in order of preference):

• Aspirin 75-325 mg daily as first-line therapy 1, 2, 3
• Aspirin 50-325 mg daily PLUS extended-release dipyridamole (superior to aspirin alone, reduced vertebrobasilar stroke/TIA from 10.8% to 5.7% in trials) 1, 2
• Clopidogrel 75 mg daily for aspirin-allergic patients or as alternative 1, 4
• Ticlopidine 250 mg twice daily (shown superior to aspirin for posterior circulation disease but less commonly used due to side effect profile) 1

Important: Dual antiplatelet therapy (aspirin + clopidogrel) increases hemorrhage risk and is NOT recommended 1

Diagnostic Imaging Requirements

Obtain MRA or CTA immediately—these have 94% sensitivity versus only 70% for ultrasound in detecting vertebral artery pathology. 1, 2

Imaging Algorithm:

• Initial: MRA with fat saturation protocols or CTA for diagnosis 1, 2
• Pre-intervention: Catheter-based angiography is required before any revascularization, as neither MRA nor CTA reliably delineates vertebral artery origins 1, 2
• Follow-up: Serial noninvasive imaging at intervals to assess healing and progression 2, 4

Indications for Endovascular or Surgical Intervention

Reserve revascularization for patients with persistent or recurrent ischemic symptoms despite optimal medical therapy. 1, 3

Endovascular Treatment (Angioplasty/Stenting)

• Risks: Death 0.3%, periprocedural neurological complications 5.5%, posterior stroke 0.7% 1, 2, 4, 3
• Restenosis rate: 26% at mean 12 months follow-up 1, 2, 4, 3
• Consider for: Patients failing medical therapy or with hemodynamically significant lesions causing recurrent symptoms 5, 6

Surgical Options

• Trans-subclavian vertebral endarterectomy 1
• Vertebral artery transposition to ipsilateral common carotid artery 1, 2, 4
• Vertebral artery reimplantation with vein graft extension to subclavian artery 1, 2, 4
• Mortality rates: 0-4% for proximal reconstruction, 2-8% for distal reconstruction 1, 2
• Complication rates: 2.5-25% for proximal procedures 1, 2

Special Considerations by Lesion Type

Pseudoaneurysm Management

• Extracranial: Anticoagulation for 3 months, then transition to antiplatelet therapy 1, 2
• Intracranial: Higher rupture risk with subarachnoid hemorrhage—consider parent vessel occlusion via endovascular coiling if patient tolerates test balloon occlusion 7, 8
• Recurrence risk: Close follow-up required as pseudoaneurysms can recur even after successful coil embolization 7

Dissection-Specific Protocol

• Natural history: Recurrent stroke risk only 1-4% over 2-5 years with treatment 1
• Anatomic healing: Occurs in 72-100% of cases; incomplete healing does NOT increase recurrent stroke risk 1
• Duration of therapy: Continue anticoagulation 3-6 months, then transition to long-term antiplatelet therapy 1

Occlusion/Severe Stenosis

• Assess contralateral vertebral artery: If patent with anatomic continuity to basilar artery, usually provides sufficient collateral flow 4
• Medical therapy: Same antiplatelet regimen as above 1, 4, 3
• Revascularization: Only if bilateral disease or symptomatic despite medical therapy 4, 3

Critical Pitfalls to Avoid

• Do NOT use dual antiplatelet therapy (aspirin + clopidogrel) routinely—hemorrhage risk outweighs benefit 1
• Do NOT increase aspirin dose if ischemic event occurs on aspirin—no evidence of benefit; switch to alternative agent instead 1
• Do NOT rely on ultrasound alone for vertebral artery evaluation—sensitivity too low at 70% 1, 2
• Do NOT anticoagulate intracranial dissections with subarachnoid hemorrhage risk—may worsen hemorrhagic complications 1
• Do NOT pursue revascularization for asymptomatic healed dissections—no benefit demonstrated 1

Long-Term Management

After acute phase (3-6 months), continue indefinite antiplatelet therapy with aspirin 75-325 mg daily or aspirin plus extended-release dipyridamole. 1, 2, 3

• Risk factor modification: Treat as extracranial carotid atherosclerosis with aggressive lipid management, blood pressure control, smoking cessation 4
• Surveillance imaging: Serial MRA or CTA at 3-6 month intervals initially, then annually if stable 2, 4
• Monitor for: Recurrent posterior circulation symptoms (vertigo, diplopia, ataxia, bilateral sensory deficits) 3