What is the management approach for a patient with a tortuous and dilated left vertebral artery and possible dissection?

Management of Tortuous and Dilated Left Vertebral Artery with Possible Dissection

Confirm the diagnosis with MRA or CTA immediately, then initiate antiplatelet therapy (aspirin 75-325 mg daily) if dissection is confirmed without intraluminal thrombus, or anticoagulation for at least 3 months if thrombus is present. 1, 2

Immediate Diagnostic Confirmation

You must obtain definitive vascular imaging urgently because the clinical presentation suggests vertebral artery dissection, which carries high stroke risk in younger patients. 3, 4

• MRA or CTA is mandatory over ultrasound for initial evaluation, with 94% sensitivity versus only 70% for ultrasound in detecting vertebral artery pathology. 1, 5, 2
• Catheter-based contrast angiography is required before any revascularization procedure, as neither MRA nor CTA reliably delineates vertebral artery origins. 1, 6
• Look specifically for intraluminal thrombus on imaging, as this determines whether antiplatelet versus anticoagulation therapy is indicated. 1, 2, 6

Key Clinical Features to Assess

Evaluate for posterior circulation ischemia symptoms including:

• Vertigo, diplopia, ataxia, bilateral sensory deficits, syncope 1, 2
• Perioral numbness, blurred vision, tinnitus 1, 5
• Headache and neck pain (most common presenting symptoms in dissection) 3, 4
• Horner syndrome (classic triad with head/neck pain and stroke) 3

Medical Management Strategy

If Dissection WITHOUT Intraluminal Thrombus

Antiplatelet therapy is the cornerstone of treatment:

• Aspirin 75-325 mg daily as first-line therapy 1, 5, 2
• For aspirin contraindications: clopidogrel 75 mg daily or ticlopidine 250 mg twice daily 5, 2
• Superior option: Aspirin plus extended-release dipyridamole 200 mg twice daily reduces vertebrobasilar territory stroke/TIA from 10.8% to 5.7% compared to placebo 5, 2
• Avoid dual antiplatelet therapy (aspirin + clopidogrel) as hemorrhage risk outweighs benefit 5

If Dissection WITH Intraluminal Thrombus

Anticoagulation is generally recommended for at least 3 months, whether or not thrombolytic therapy is used initially. 1, 2, 6

This applies to acute ischemic syndromes involving the vertebral artery territory with angiographic evidence of thrombus in the extracranial portion. 1, 2, 6

Important Nuance on Anticoagulation vs Antiplatelet

The evidence remains equivocal regarding superiority of anticoagulation versus antiplatelet therapy for vertebral artery dissection. 3, 4 Case series show no clear or consistent benefit for one form of antithrombotic therapy over another. 1 However, the presence of intraluminal thrombus tips the balance toward anticoagulation for at least 3 months. 1, 2, 6

Revascularization Considerations

Revascularization should only be considered if recurrent posterior circulation ischemic symptoms persist despite optimal medical management for at least 3 months. 5, 2

Endovascular Treatment Risks

• Death: 0.3% 5, 2, 6
• Periprocedural neurological complications: 5.5% 1, 5, 2, 6
• Posterior stroke: 0.7% 5, 2, 6
• Restenosis: 26% at 12-month follow-up 5, 2, 6

Surgical Options

If medical therapy fails and revascularization is necessary:

• Trans-subclavian vertebral endarterectomy 1, 5, 6
• Transposition of vertebral artery to ipsilateral common carotid artery 1, 5, 6
• Reimplantation with vein graft extension to subclavian artery 1, 5, 6

Surgical complication rates for proximal vertebral artery reconstruction: early complications 2.5-25%, perioperative mortality 0-4%. 1, 6

Special Consideration: Tortuosity and Dilation

The combination of tortuosity and dilation raises concern for:

• Vertebrobasilar dolichoectasia: fusiform dilatation, elongation, and tortuosity of vertebral and basilar arteries 1
• Fibromuscular dysplasia (FMD): can cause arterial stenosis, occlusion, intraluminal thrombus, aneurysm, or dissection with "string of beads" appearance 1

If FMD is identified, the same antiplatelet therapy approach applies, with BP control and lifestyle modification. 1

Long-Term Monitoring

• Continue indefinite antiplatelet therapy with aggressive cardiovascular risk factor modification 5
• Serial noninvasive imaging (MRA or CTA) to assess disease progression and exclude new lesions 5, 2
• Monitor continuously for recurrent symptoms, as atheroembolism from vertebral artery origin lesions may cause brainstem or cerebellar infarction even when the contralateral vertebral artery is patent 5

Critical Pitfall to Avoid

Do not delay imaging or treatment initiation. Vertebral artery dissection can be insidious and is a leading cause of stroke in young patients, second only to cardioembolic events. 3 The dissection may occur after minor trauma or even spontaneously, and delayed presentation (even weeks after initial injury) is well-documented. 3, 7