• Reversible cerebral vasoconstriction syndrome (RCVS) is the second most common cause of thunderclap headache after aneurysmal subarachnoid hemorrhage (SAH) and the most common cause of recurrent thunderclap headaches.
• Up to 40% of patients with RCVS have a history of migraine.
• It is associated with selective serotonin reuptake inhibitors (SSRIs), triptans, cocaine, marijuana, tacrolimus, oral contraceptives, as well as the peripartum period.
• Symptoms are often triggered by emotional stress, sexual activity, showering, straining, and physical exertion.
• Although the vasoconstriction is reversible, it can cause intracranial hemorrhage, seizures, stroke, and coma.
• Diagnosis is by history, cerebral angiography and exclusion of aneurysmal SAH.

Bottom Line: Consider RCVS in the differential of thunderclap headache and in patients who present with worse than usual migraine headache.

References

Arrigan MT, Heran MKS, Shewchuk JR. Reversible cerebral vasoconstriction syndrome: an important and common cause of thunderclap and recurrent headaches. Clin Radiol. 2017 Dec 21 [Epub ahead of print]

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