Can you get a subacute vertebral artery dissection?

Vertebral Artery Dissection: Diagnosis and Management

Yes, vertebral artery dissection can present in the subacute phase. Vertebral artery dissection (VAD) occurs when an intimal tear initiates an intramural hematoma, which can present in acute, subacute, or chronic phases depending on the timing of diagnosis relative to symptom onset 1.

Clinical Presentation

• Vertebral artery dissection typically presents with headache, neck pain, vertigo, nausea, visual disturbances, or syncope 1
• Some patients develop sudden catastrophic neurological events, while others have a more gradual onset of symptoms 1
• After initial warning symptoms, cerebral or retinal ischemia develops in 50-95% of cases 1
• VAD accounts for approximately 10-15% of ischemic strokes in patients under 45 years of age 2, 3

Risk Factors

• Sudden or excessive neck movement (hyperflexion/hyperextension) 1
• Minor trauma including chiropractic manipulation 1
• Connective tissue disorders (Ehlers-Danlos syndrome, Marfan syndrome) 1, 4
• Fibromuscular dysplasia (associated with approximately 15% of cases) 1
• Penetrating trauma and amphetamine abuse 1

Diagnostic Imaging

• CT Angiography (CTA) of the head and neck with IV contrast is the preferred initial diagnostic modality with the highest reported sensitivity (100%) 2, 3
• MR Angiography (MRA) has a sensitivity of approximately 77% compared to conventional angiography 2, 3
• Carotid duplex ultrasonography may identify a dissection flap and differential flow in true and false lumens, but has limited utility for dissections beginning above the angle of the mandible 1, 3
• Important to note that VAD can present with a normal-appearing lumen on imaging, with wall thickening ("suboccipital rind" sign) as the only imaging sign of dissection 5
• Catheter-based Digital Subtraction Angiography is the traditional gold standard but now largely supplanted by CTA and MRA 2, 3

Management

Antithrombotic Therapy

• Antithrombotic treatment for at least 3-6 months is recommended for patients with vertebral artery dissection associated with ischemic stroke or TIA (Class IIa recommendation) 1, 3
• Options include:
  • Anticoagulation with heparin, low-molecular-weight heparin, or warfarin (target INR 2.0-3.0) 1, 3
  • Antiplatelet therapy with aspirin, clopidogrel, or the combination of extended-release dipyridamole plus aspirin 1, 3
• After the initial 3-6 month period, transition to antiplatelet therapy is typically recommended 3

Invasive Treatment

• Surgical or endovascular revascularization is reserved for patients with persistent or recurrent symptoms that fail to respond to antithrombotic therapy 1, 3
• Endovascular options include angioplasty and stenting (Class IIb recommendation) 1, 6
• Protected stent-assisted angioplasty may be considered in selected cases 6

Prognosis and Follow-up

• With appropriate antithrombotic treatment, the prognosis is usually favorable 1, 3
• The annual rate of recurrent stroke, TIA, or death was reported as 8.3% in patients treated with anticoagulants versus 12.4% in those treated with aspirin in one observational study 3

Important Clinical Considerations

• Maintain a high index of suspicion in younger patients with posterior circulation stroke symptoms 2, 3
• Imaging should include the entire vertebral artery from origin to basilar artery, as dissection may involve any portion 2
• Anticoagulation may adversely influence the outcome if subarachnoid hemorrhage occurs due to intracranial extension of the dissection 3, 7
• VAD can be easily overlooked if only lumen-opacifying studies are performed, as the arterial lumen at the dissection site may be normal in caliber 5