What is the recommended diagnostic work‑up and management for reversible cerebral vasoconstriction syndrome (RCVS) in adults?

Reversible Cerebral Vasoconstriction Syndrome (RCVS): Diagnostic Work-Up and Management

For adults with suspected RCVS, initiate immediate non-invasive vascular imaging (CTA or MRA) to confirm multifocal cerebral artery narrowing, remove all vasoactive triggers, and start nimodipine 60 mg every 4 hours as first-line therapy while avoiding glucocorticoids which worsen outcomes. 1, 2

Clinical Recognition and Triggers

RCVS presents with recurrent thunderclap headaches occurring over approximately 1-2 weeks, often maximal at onset, with or without focal neurological deficits. 3, 4, 5

Key Triggers to Identify and Remove:

• Vasoactive substances: serotonergic agents (SSRIs, triptans), sympathomimetic drugs (decongestants), cannabis, and illicit drugs 1, 6
• Precipitating activities: sexual activity, exertion, Valsalva maneuvers, showering 3
• Postpartum state (occurs in approximately 8% of cases) 5
• Over 80% of patients have identifiable triggers that must be discontinued immediately 7

Clinical Patterns:

• Women are affected more frequently (64% in prospective series), tend to be older, and have higher rates of stroke and cortical subarachnoid hemorrhage 5
• Approximately one-third of patients experience blood pressure surges accompanying headache attacks 7
• Headaches recur daily for approximately 1 week, while vasoconstriction may persist for weeks to months 5

Diagnostic Work-Up

Initial Imaging Strategy:

Obtain CTA or MRA of head and neck as first-line imaging to demonstrate the characteristic "string and beads" appearance of multifocal segmental cerebral artery narrowing. 8, 3, 4

• CTA head and neck with IV contrast is rated 8/9 (usually appropriate) for initial evaluation 8
• MRA head and neck (with or without contrast) is equally rated 8/9 8
• Catheter digital subtraction angiography (DSA) is the gold standard but should be reserved for cases with inconclusive non-invasive imaging, as the procedure itself may provoke vasoconstriction 3, 2

Brain Parenchymal Imaging:

MRI brain without and with contrast is rated 9/9 for initial screening to detect complications. 8

• MRI is more sensitive than CT for detecting acute ischemic changes 8
• Look for: cortical subarachnoid hemorrhage (22%), intracerebral hemorrhage (6%), ischemic infarcts (4%), and posterior reversible encephalopathy syndrome (PRES) features (9%) 5

Laboratory Studies:

• Complete blood count, inflammatory markers (ESR, CRP) to help differentiate from primary CNS vasculitis 1
• Lumbar puncture is NOT routinely indicated unless meningitis or aneurysmal SAH cannot be excluded; CSF is typically normal or shows mild protein elevation without pleocytosis in RCVS 2, 4

Transcranial Doppler Monitoring:

• Mean flow velocity >120 cm/s in the middle cerebral artery identifies patients at higher risk for ischemic complications 7

Critical Differential Diagnoses to Exclude

The most dangerous misdiagnoses are aneurysmal subarachnoid hemorrhage and primary CNS vasculitis (PACNS), which require fundamentally different management. 2, 4

Distinguishing Features:

Feature	RCVS	Aneurysmal SAH	PACNS
Headache pattern	Recurrent thunderclaps over 1-2 weeks	Single thunderclap	Subacute/chronic
CSF	Normal or mild protein elevation	Xanthochromia, RBCs	Elevated protein, pleocytosis
Angiography	Reversible multifocal narrowing	Aneurysm	Progressive narrowing
Time course	Resolves in 1-3 months	Stable aneurysm	Progressive

2, 4

Management Algorithm

Immediate Actions (First 24-48 Hours):

1. Remove all vasoactive triggers immediately (medications, illicit drugs) 1, 2
2. Start nimodipine 60 mg orally every 4 hours (first-line pharmacotherapy) 1, 2
3. Maintain euvolemia; avoid prophylactic hemodynamic augmentation which can cause iatrogenic harm 1
4. Bed rest and analgesics for supportive care 2

Blood Pressure Management:

• Avoid aggressive blood pressure augmentation as prophylaxis 1
• For symptomatic vasospasm with neurological deterioration, elevating systolic blood pressure may be reasonable to reduce progression of delayed cerebral ischemia 1
• Monitor for blood pressure surges during headache attacks 7

Medications to AVOID:

Glucocorticoids are contraindicated - they are an independent predictor of worse outcomes and should be avoided entirely. 2

Refractory Cases:

For severe vasospasm with neurological deterioration despite medical management:

• Intra-arterial nimodipine or verapamil can be considered 1
• Cerebral angioplasty may be reasonable for severe vasospasm refractory to medical therapy 1
• Reserve invasive neurointerventional techniques for severe deteriorating cases only 2

Complications and Their Time Course

Hemorrhagic complications occur early (first week), while ischemic events occur later (second week). 5

Early Complications (First Week):

• Cortical subarachnoid hemorrhage (22%)
• Intracerebral hemorrhage (6%)
• Seizures (3%)
• PRES (9%)

Later Complications (Second Week):

• TIAs (16%)
• Cerebral infarction (4%)

5

Follow-Up Imaging

Repeat vascular imaging at 3 months to confirm resolution of vasoconstriction and establish the diagnosis definitively. 2, 4

• Vasoconstriction should completely resolve within 1-3 months 4, 5
• Persistent narrowing beyond 3 months suggests alternative diagnosis (PACNS, atherosclerosis) 2

Prognosis and Pitfalls

Most patients (90-95%) recover without permanent neurological deficits, though 5-10% are left with permanent disability and rare deaths occur. 2

Common Pitfalls:

• Misdiagnosing as aneurysmal SAH and performing unnecessary catheter angiography, which may worsen vasoconstriction 3, 4
• Misdiagnosing as PACNS and inappropriately treating with glucocorticoids, which worsens outcomes 2
• Performing lumbar puncture routinely when imaging already confirms the diagnosis 2
• Failing to identify and remove vasoactive triggers, which is the cornerstone of management 1, 2

Relapse:

• Relapse is rare but has been reported in a small proportion of patients during follow-up 2, 7
• No relapses were observed in one prospective series with mean follow-up of 16 months 5