01Approach to the Critical Patient/attcp67

Immediate priorities

›Vertebral artery dissection recognition

›Posterior neck pain or occipital headache with new neurologic symptoms

›Abrupt or subacute onset

›Pain often precedes stroke symptoms by hours to days

›Posterior circulation deficit pattern

›Dizziness, diplopia, dysarthria, dysphagia, drop attack

›Ataxia, nystagmus, numbness, nausea and vomiting

›Mechanical trigger history

›Recent cervical spine manipulation, extreme neck rotation, or minor trauma

›Trivial mechanism does not exclude dissection

›Segment and hemorrhage risk triage

›Extracranial dissection (V1 to V3)

›Antithrombotic therapy is the primary treatment axis

›Lower subarachnoid hemorrhage risk

›Intracranial dissection (V4)

›Dissects into or through a dural arterial segment lacking external elastic lamina

›Subarachnoid hemorrhage risk changes anticoagulation decision

›If thunderclap headache or meningismus, non-contrast CT head before any antithrombotic

›Exclude subarachnoid hemorrhage from intracranial extension or rupture

›Neurosurgery activation if hemorrhage present

›If acute posterior circulation stroke deficits, activate stroke code

›Time last known well drives thrombolysis and thrombectomy eligibility

›Cervical artery dissection is not an absolute contraindication to IV thrombolysis

›Aortic arch dissection and intracranial hemorrhage remain absolute contraindications

›Parallel processing of imaging, labs, and neurology notification

›Door-to-CT target under 25 minutes

›Door-to-needle target under 60 minutes for IV thrombolysis

›Suspected basilar artery occlusion (altered consciousness, quadriparesis, locked-in features)

›Neurointerventional activation before CTA confirmation if resources allow

›Thrombectomy benefit window extends beyond 24 hours in basilar occlusion

Hemodynamic and monitoring targets

›Blood pressure strategy

›Permissive hypertension when no reperfusion therapy planned

›Avoid lowering BP unless over 220/120 mmHg

›Rationale is preserving flow through a stenosed or narrowed dissected segment

›Pre-thrombolysis target SBP under 185 mmHg and DBP under 110 mmHg

›Labetalol 10 to 20 mg IV over 1 to 2 minutes, may repeat once, maximum 40 mg

›Nicardipine infusion 5 mg/hour, titrate by 2.5 mg/hour every 5 to 15 minutes, maximum 15 mg/hour

›Post-thrombolysis target SBP under 180 mmHg and DBP under 105 mmHg for 24 hours

›Avoid SBP below 120 mmHg because it reduces collateral perfusion

›Exceptions to standard thresholds

›Chronic hypertension shifts the autoregulation curve rightward, tolerate higher permissive values

›Bow Hunter syndrome physiology depends on head position, not blood pressure alone

›Monitoring bundle

›Continuous cardiac monitor for arrhythmia from brainstem autonomic involvement

›Lateral medullary infarction can produce bradycardia or blood pressure lability

›Continuous pulse oximetry, SpO2 target 94 to 98%

›Supplemental oxygen only if SpO2 under 94%

›Avoid hyperoxia, which can promote cerebral vasoconstriction and reduce collateral flow

›Serial neurologic checks every 15 minutes for the first 2 hours after reperfusion therapy, then hourly

›Watch specifically for new bulbar dysfunction, worsening ataxia, or declining consciousness

›Airway and swallow monitoring

›Bulbar signs (dysarthria, dysphagia, absent gag) predict aspiration risk

Immediate consults and escalation triggers

›Consultation triggers

›Vascular neurology or stroke neurology at presentation

›All confirmed or suspected cervical artery dissection with neurologic deficit

›Neurointerventional radiology

›Large vessel occlusion, basilar occlusion, or flow-limiting pseudoaneurysm

›Neurosurgery

›Intracranial (V4) dissection with subarachnoid hemorrhage

›Cerebellar infarction with brainstem compression or hydrocephalus risk

›Deterioration triggers

›Recurrent transient symptoms despite antithrombotic therapy

›Reimage for dissection progression, new thrombus, or pseudoaneurysm enlargement

›Consider escalation to endovascular therapy

›Progressive brainstem or cerebellar signs

›Basilar artery extension or occlusion concern

›Malignant cerebellar edema with fourth ventricle compression

02History/hx66

Presentation pattern

›Pain characteristics

›Posterior neck pain

›Ipsilateral to the dissected artery

›Present in a substantial majority of confirmed cases

›Occipital headache

›Dull, throbbing, or unfamiliar in quality compared to prior headaches

›New or different headache pattern is a key clue

›Interval between pain onset and neurologic symptoms

›Hours to days in most cases

›Delayed presentation is common and increases missed-diagnosis risk

›Sentinel and warning symptoms

›Transient dizziness, diplopia, or dysarthria preceding a completed stroke

›Represents vertebrobasilar TIA

›Recurrence within days to weeks carries high stroke risk

›Thunderclap headache

›Consider intracranial (V4) dissection with subarachnoid extension

›Non-contrast CT head before further workup

Precipitants and mechanical triggers

›Mechanical events

›Cervical spine manipulation (chiropractic or osteopathic)

›Recognized precipitant, particularly for extracranial V3 segment injury

›Association does not require high-force manipulation

›Extreme or sustained neck rotation or hyperextension

›Sports, yoga, ceiling painting, hairdresser positioning

›Coughing, vomiting, or sneezing reported in some cases

›Minor cervical trauma

›Trivial mechanism does not exclude dissection

03Physical Exam/exam45

Vital signs and vascular exam

›Blood pressure

›Bilateral arm pressures

›Asymmetry over 20 mmHg suggests concomitant subclavian or aortic arch process

›Hypertension common and often reactive

›Do not treat aggressively before thrombolysis decision is made

›Neck and vascular findings

›Cervical bruit

›Nonspecific but supportive when present

›Neck tenderness or limited range of motion

›Nonspecific musculoskeletal overlap

›Carotid and peripheral pulses

›Assess for concurrent carotid dissection or systemic vasculopathy

Cranial nerve and brainstem findings

›Ocular motor and gaze findings

›Nystagmus

›Direction-changing or vertical nystagmus favors central vestibular cause

›Skew deviation

›Vertical misalignment suggests brainstem localization

›Internuclear ophthalmoplegia

›Bulbar and lower cranial nerve findings

›Dysarthria

›Dysphagia and absent or asymmetric gag reflex

›Aspiration risk driver

›Hoarseness or vocal cord palsy

›Nucleus ambiguus involvement in lateral medullary syndrome

›Cerebellar findings

›Limb and truncal ataxia

04Differential Diagnosis/ddx41

Cannot-miss diagnoses

›Basilar artery occlusion

›ICD-10 I63.22

›Coma, quadriplegia, locked-in syndrome

›Can result from vertebral dissection propagation

›Subarachnoid hemorrhage

›ICD-10 I60.x

›Thunderclap headache, meningismus

›Consider intracranial (V4) dissection as the source

›Internal carotid artery dissection

›ICD-10 I77.74

›Isolated Horner syndrome with full anhidrosis, or anterior circulation deficit

›Differentiating clue against vertebral dissection when posterior circulation signs are absent

›Giant cell arteritis

›ICD-10 M31.6

›Age over 50, jaw claudication, temporal tenderness, visual symptoms

›Elevated ESR and CRP redirect diagnosis toward vasculitis rather than dissection

Vertebrobasilar stroke syndromes

›Lateral medullary (Wallenberg) syndrome

›Posterior inferior cerebellar artery territory

›Crossed sensory loss, ipsilateral Horner, ipsilateral ataxia, dysphagia, hiccups

›Cerebellar infarction

›Posterior inferior, anterior inferior, or superior cerebellar artery territory

›Risk of malignant edema with brainstem compression over 24 to 48 hours

›Bow Hunter syndrome

›Positional vertebrobasilar insufficiency from rotational compression of the dominant vertebral artery

›Symptoms reproducible with head turning and resolve with neutral positioning

05Laboratory Tests/lt22

Diagnostic and rule-out labs

›Complete blood count and coagulation panel

›Baseline before antithrombotic initiation

›Platelets under 100,000 per microliter is a caution for thrombolysis and anticoagulation

›PT/INR and aPTT for baseline coagulation status

›D-dimer

›Not validated as a rule-out test for cervical artery dissection

›Unlike aortic dissection, no established D-dimer threshold excludes vertebral dissection

›A normal D-dimer must not delay imaging

›ESR and CRP

›Ordered when giant cell arteritis is a competing consideration

›Marked elevation redirects workup toward vasculitis rather than dissection

›Normal inflammatory markers do not exclude dissection, since dissection itself does not typically elevate them

Pre-procedural and connective tissue labs

›Pre-thrombolysis and pre-anticoagulation labs

›Point-of-care glucose

›Hypoglycemia under 3.0 mmol/l corrected before attributing deficits to stroke

›Renal function

›Creatinine for contrast planning and DOAC dosing

›Selected connective tissue and hypercoagulability workup

›Genetic testing for vascular Ehlers-Danlos syndrome (COL3A1) when recurrent or multiple dissections

›Hypercoagulability panel in young patients with no mechanical trigger identified

›Draw before anticoagulation initiation when feasible

›Interpret with caution in the acute phase, since acute-phase reactants affect results

06Diagnostic Tests/dt43

Scoring Systems

›NIHSS

›Quantifies posterior circulation stroke severity

›NIHSS systematically underestimates posterior circulation and cerebellar stroke severity

›Isolated ataxia, vertigo, or dysarthria contribute few points despite significant deficit

›Low NIHSS does not exclude a disabling posterior circulation stroke

›No validated dissection-specific pretest probability score

›Unlike the Aortic Dissection Detection Risk Score for aortic dissection, no comparably validated clinical prediction rule exists for cervical artery dissection

›Diagnosis is driven by clinical suspicion (neck pain or headache plus posterior circulation symptoms) combined with imaging rather than a scoring algorithm

MRI

›MRI and MRA neck

›Fat-saturated T1 axial sequence

›Crescent-shaped hyperintense intramural hematoma is the classic finding

›Best seen in the subacute phase, roughly 3 to 7 days after onset, when hematoma is methemoglobin-rich

›Hyperacute hematoma may be isointense and easily missed

›Time-of-flight MRA

›Can show intimal flap, double lumen, or luminal narrowing

›Lower sensitivity than CT angiography for occlusion and flap detection

›MRI brain

›DWI for associated posterior circulation infarct

›Preferred over CT for posterior fossa pathology when clinical uncertainty persists and time permits

›Do not delay thrombectomy to obtain MRI

CT

›CT angiography of the head and neck

›First-line diagnostic study

›High sensitivity for intimal flap, string sign, pseudoaneurysm, and occlusion

›Identifies segment involved (V1 through V4) and associated large vessel occlusion

›String sign

07Disposition/dispo22

Level of care

›Admission for all confirmed cervical artery dissection

›Highest stroke risk in the first 2 weeks after diagnosis

›Even isolated dissection without infarct warrants inpatient observation in most practice

›Stroke unit or ICU for dissection with completed infarct

›Serial neurologic checks

›Telemetry for arrhythmia detection

›Escalated level of care triggers

›Basilar artery occlusion or extension

›Cerebellar infarction with edema or hydrocephalus risk

›Intracranial (V4) dissection with subarachnoid hemorrhage

Transfer and discharge criteria

›Transfer indications

›No on-site neurointerventional capability with large vessel or basilar occlusion

›Drip and ship, administer IV thrombolysis if eligible before transfer

›Do not delay thrombolysis for transfer logistics

›Suspected Bow Hunter syndrome or pseudoaneurysm requiring surgical or endovascular evaluation

›Vascular neurosurgery or neurointerventional acceptance

›Discharge criteria after stabilization

›Antithrombotic regimen established and tolerated

›No recurrent transient symptoms

›Stable follow-up imaging plan in place

›Repeat CT angiography or MRA typically at 3 to 6 months to assess healing

›Neurologically stable or improving with a rehabilitation plan if deficits persist

08Treatment/t99

Antithrombotic therapy

›Extracranial (V1 to V3) dissection without hemorrhage

›Antiplatelet therapy

›Aspirin 300 mg orally once, then 75 to 100 mg orally daily

›Anticoagulation as an alternative

›Heparin infusion without bolus if bleeding risk present, titrated to institutional aPTT target

›If no bleeding risk, bolus 60 to 80 units/kg IV followed by infusion 12 to 18 units/kg/hour

›Titrate every 6 hours to therapeutic aPTT

›Transition to a DOAC or warfarin for continued anticoagulation

›CADISS trial evidence

›No significant difference in recurrent stroke between antiplatelet and anticoagulant therapy

›Recurrent stroke rate was low in both arms, approximately 1% at 3 months

›Duration and choice

›Typical treatment duration 3 to 6 months pending healing on follow-up imaging

›Transition to long-term antiplatelet therapy if imaging shows healing

›Continue longer if pseudoaneurysm or persistent flow abnormality remains

›Therapy is not working

›Recurrent transient ischemic symptoms despite adequate antithrombotic therapy

›Reimage for dissection progression, new thrombus, or enlarging pseudoaneurysm

›Consider switching antiplatelet to anticoagulation or vice versa

›Consider endovascular therapy if a fixed hemodynamically significant lesion is identified

Intracranial (V4) dissection and hemorrhage considerations

›Anticoagulation caution

›Anticoagulation is relatively contraindicated in intracranial (V4) dissection

›Intracranial segment lacks external elastic lamina and adventitia is thin

›Anticoagulation raises subarachnoid hemorrhage risk from a dissecting aneurysm

›Antiplatelet therapy generally preferred over anticoagulation when intracranial extension is present without hemorrhage

›If subarachnoid hemorrhage present

›Hold all antithrombotic therapy

›Neurosurgery and neurointerventional consultation

›Endovascular occlusion or trapping of the dissecting segment

›Balloon test occlusion of the contralateral vertebral artery adequacy before sacrifice

›Flow-diverting stent as an alternative when vessel preservation is feasible

Acute ischemic stroke reperfusion therapy

›IV thrombolysis

›Alteplase 0.9 mg/kg IV, maximum 90 mg

›10% of total dose as bolus over 1 minute

›Remaining 90% as infusion over 60 minutes

›Eligible window within 4.5 hours of last known well

›Tenecteplase 0.25 mg/kg IV, maximum 25 mg, single bolus

›Reasonable alternative to alteplase

›Cervical artery dissection is not an absolute contraindication to IV thrombolysis

›Aortic arch dissection and intracranial hemorrhage remain absolute contraindications

›Theoretical risk of extending the dissection or expanding a periarterial hematoma exists but has not been shown to outweigh reperfusion benefit in cohort data

›Post-thrombolysis monitoring

›Neurologic checks every 15 minutes for 2 hours, then hourly for 22 hours

›No antiplatelet or anticoagulant for 24 hours after thrombolysis

›Repeat non-contrast CT head at 24 hours before initiating antithrombotics

›Mechanical thrombectomy

›Confirmed large vessel or basilar occlusion within standard or extended window

›Door-to-groin puncture target under 90 minutes for direct arrivals

›Basilar artery occlusion

›Time window flexible, benefit reported beyond 24 hours in selected cases

›High mortality without recanalization

Interventional and surgical options

›Endovascular stenting

›Flow-limiting stenosis or enlarging pseudoaneurysm refractory to medical therapy

›Dual antiplatelet therapy required after stent placement

›Aspirin 81 mg plus clopidogrel 75 mg daily, typically for 1 to 3 months, then single agent long-term

›Surgical decompression for Bow Hunter syndrome

›Recurrent positional vertebrobasilar ischemia despite conservative measures

›C1-C2 fusion or bony decompression of the compressing structure

›Osmotherapy for malignant cerebellar edema

›Mannitol 0.5 to 1 g/kg IV over 20 minutes, may repeat every 4 to 6 hours

›Maintain serum osmolality under 320 mOsm/l

›Monitor serum sodium and obtain ECG surveillance for hypernatremia-associated QTc prolongation and arrhythmia during repeated dosing

›Hypertonic saline 23.4% 30 to 60 mL via central line for refractory intracranial pressure

›Monitor serum sodium at least every 6 hours during active titration

›Neurosurgical decompression for brainstem compression or hydrocephalus

›Suboccipital craniectomy or external ventricular drain as indicated

Iatrogenic harms and interventions to avoid

›Intubation

›Neck hyperextension during laryngoscopy can mechanically extend a dissection, particularly in the mobile V3 segment

›In-line neutral positioning and video laryngoscopy preferred

›Bulbar dysfunction (absent gag, dysphagia) is an indication for airway protection

›Avoid induction-related hypotension, which reduces perfusion through the narrowed dissected segment

›Sedation

›Can mask evolving neurologic exam needed for serial stroke monitoring

›Propofol-associated hypotension reduces cerebral perfusion pressure through the stenosed vessel

›Fluid loading

›Maintain euvolemia with isotonic fluids

›Avoid hypotonic fluids, which worsen cerebral edema

›Avoid hypovolemia, which compounds hypoperfusion in a permissive-hypertension strategy

›Oxygen

›Supplemental oxygen only if SpO2 under 94%

›Hyperoxia is not beneficial and may promote vasoconstriction, reducing collateral flow

›Vasopressors

›Not routine, but appropriate if permissive hypertension is undermined by iatrogenic hypotension (for example, sedation or overcorrection with antihypertensives)

›Goal is restoring perfusion pressure through the dissected segment, not a fixed pressor protocol

›Mechanical circulatory support

›Intra-aortic balloon pump and other mechanical circulatory support are not indicated

›Vertebral artery dissection is a cervical arterial process, not a cardiac output problem

›Anticoagulation

›Contraindicated in intracranial (V4) dissection with subarachnoid hemorrhage

›Relatively contraindicated with a large completed infarct due to hemorrhagic transformation risk

›Acceptable in extracranial dissection without hemorrhage, with outcomes similar to antiplatelet therapy

›Fibrinolysis

›Not an absolute contraindication for cervical artery dissection causing acute ischemic stroke

›Remains absolutely contraindicated if aortic arch dissection or intracranial hemorrhage is present

›Analgesia

›IV opioids for severe neck pain or headache, fentanyl 25 to 50 mcg IV titrated, or morphine 2 to 4 mg IV titrated

›Acetaminophen 650 to 1000 mg orally or IV every 4 to 6 hours, maximum 4000 mg per 24 hours, as a non-sedating first-line option

›Use opioids cautiously once anticoagulation is initiated, since oversedation can mask a change in neurologic exam

›NSAIDs used with caution once an antithrombotic plan is set, given additive bleeding risk with anticoagulation

09Special Populations/sp53

Pregnancy

›Epidemiology and risk in pregnancy

›Cervical artery dissection is uncommon in pregnancy but reported in the peripartum period

›Valsalva during labor is a proposed mechanical contributor

›Imaging in pregnancy

›MRI and MRA without contrast preferred

›CT angiography with abdominal shielding when benefit outweighs radiation risk

›Antithrombotic therapy in pregnancy

›LMWH (enoxaparin) preferred anticoagulant, safe in pregnancy

›Warfarin contraindicated, teratogenic and associated with fetal hemorrhage

›DOACs contraindicated in pregnancy

›Aspirin 81 to 162 mg daily acceptable in the second and third trimester

›Thrombolysis in pregnancy

›Alteplase is not an absolute contraindication

›Placental bleeding is the main theoretical concern

›Multidisciplinary decision with maternal-fetal medicine

›Blood pressure management in pregnancy

›Avoid ACE inhibitors and ARBs, teratogenic

›Labetalol and hydralazine preferred antihypertensives

Geriatric

›Presentation differences

›Atypical or minimized neck pain reporting is common

›Dissection is a less common stroke cause in this age group than large-artery atherosclerosis or cardioembolism, but still occurs, often superimposed on an atherosclerotic vessel

›Thrombolysis and anticoagulation considerations

›No upper age limit for IV alteplase or tenecteplase

›Higher rate of symptomatic intracranial hemorrhage over age 80, approximately 7 to 9% versus 5 to 6% overall

›Renal function affects DOAC dosing

›Dabigatran requires creatinine clearance above 30 mL/min

10Background/b45

Epidemiology

›Incidence

›Vertebral artery dissection incidence approximately 1 to 1.5 per 100,000 per year

›Combined cervical (carotid plus vertebral) artery dissection incidence approximately 2.6 to 3 per 100,000 per year

›Accounts for approximately 2% of all ischemic strokes overall

›Accounts for up to approximately 25% of ischemic strokes in patients under age 45

›Demographics

›Mean age of onset in the mid-40s, younger than typical atherosclerotic stroke

›No strong sex predominance established for vertebral dissection specifically

›Multiplicity and recurrence

›Multiple or bilateral cervical artery dissection in roughly 10 to 16% of cases

›Recurrent dissection risk approximately 1% per year after the index event

›Higher recurrence risk with an underlying connective tissue disorder or strong family history

›Outcomes

›Overall mortality is low, generally under 5%

›Higher mortality with bilateral vertebral involvement or basilar artery extension

›Most patients with extracranial dissection and appropriate antithrombotic therapy have a favorable long-term vascular outcome

Pathophysiology

›Anatomic segments

›V1 segment, origin from the subclavian artery to the C6 transverse foramen

›V2 segment, within the transverse foramina from C6 to C2

›V3 segment, exits the C2 transverse foramen and loops around the atlas before piercing the dura

›Most mobile segment, most susceptible to mechanical and rotational injury

›V4 segment, intradural from the dura to the vertebrobasilar junction

›Lacks external elastic lamina and has a thin adventitia

›Dissection here carries disproportionate subarachnoid hemorrhage risk

›Mechanism of dissection

›Intimal tear allows blood to enter the arterial wall

11Patient Discharge Instructions/pdi24

copy discharge instructions

›What happened to you

›A tear formed in the wall of an artery in your neck that supplies part of your brain

›This can cause a blood clot to form or reduce blood flow to the back of your brain

›Most of these arteries heal over the following 3 to 6 months with treatment

›Your medications

›Take your blood thinner or aspirin exactly as prescribed every day

›Do not stop your blood thinner or aspirin without talking to your doctor first

›Do not start any new over-the-counter medication, supplement, or herbal remedy without checking first, since some increase bleeding risk

›Activity guidance

›Avoid chiropractic neck manipulation and cervical spine adjustment until your doctor clears you

›Avoid extreme or forceful neck rotation and hyperextension, including certain yoga poses and contact sports

›Avoid heavy lifting and straining

›Light to moderate walking is encouraged

›Follow-up appointments

›Vascular neurology or stroke clinic within 1 to 2 weeks of discharge

›Repeat CT angiography or MRA at 3 to 6 months to check healing

›Primary care within 2 to 4 weeks

›Return to the emergency department immediately if you develop

›New or worsening neck pain or headache

›New dizziness, double vision, slurred speech, or trouble swallowing

›New weakness or numbness, especially on one side or crossing sides of the body and face

›Sudden severe headache unlike any you have had before

›A new fall or drop attack without warning

›Any sign of unusual bleeding or bruising if you are taking a blood thinner

12References/r10

Guidelines and key sources

›AHA/ASA scientific statement on treatment and outcomes of cervical artery dissection in adults

›Yaghi S, et al. Stroke. 2024

›European Stroke Organisation guideline on the diagnosis and management of cervical artery dissection

›Debette S, et al. European Stroke Organisation. 2021

›AHA/ASA guideline for early management of patients with acute ischemic stroke

›Powers WJ, Rabinstein AA, Ackerson T, et al. Stroke. 2018

›Established IV thrombolysis and thrombectomy eligibility criteria applied to dissection-related stroke

Landmark trials

›CADISS trial (Cervical Artery Dissection in Stroke Study)

›CADISS trial investigators. Lancet Neurology. 2015

›Randomized antiplatelet versus anticoagulant therapy, no significant difference in recurrent stroke at 3 months

Evidence & Review

Evidence & Review