Reversible Cerebral Vasoconstriction Syndrome (RCVS)

Author: Robby Allen, MD

Answer to last week’s case: reversible cerebral vasoconstriction syndrome (RCVS). Congrats to Drs. Solger and Cerbini for getting the correct diagnosis.

Who gets RCVS?

RCVS occurs more commonly in women, often in the middle-aged years. The exact incidence is unknown but it may not be that uncommon: a retrospective review from a single hospital in Paris identified 67 cases over a three-year period. [1]

How does RCVS present?

The clinical course of RCVS varies but classically presents with a thunderclap headache (pain climaxing within one minute). The headache will be described as excruciating, often bilateral and originating from the occiput before spreading diffusely. Associated symptoms include nausea, vomiting, photophobia, and phonophobia. In more severe cases, patients may present with seizure (1-17%) or even mimic stroke or TIA. [2] Visual deficits will be the most common focal deficit (think posterior circulation), but may present with sensory, motor or even speech deficits.

Let’s pause. This all sounds interesting but how am I going to differentiate RCVS from more common headache syndromes (e.g. subarachnoid hemorrhage, migraine, trigeminal neuralgia, etc)?

Think RCVS when a patient describes a series of short lived (often 1-3 hours) headaches, occurring over a period of one to four weeks. Patients with RCVS may also have an identifiable trigger (see figure 1). (Clues from the presented case were SSRI, pseudoephedrine, and triptan use).

Triggers of RCVS [2]

Be afraid of pregnant and recently pregnant women

Headache in pregnant or postpartum women may challenge providers. In addition to the normal differential, provides should consider additional secondary causes including pituitary apoplexy (Sheehan Syndrome), preeclampsia, cerebral venous thrombosis, posterior reversible encephalopathy syndrome (PRES), post lumbar puncture headache (if a woman had an epidural), and RCVS.

Interestingly, experts believe there may be an overlap between PRES and RCVS. While thought to be associated with severe hypertension, up to one-quarter of patients with PRES are normotensive. [3] Similarly, up to one-third of patients with RCVS may be hypertensive during acute episodes. Radiographically, all PRES patients will have transient vasogenic edema whereas only 8-38% of RCVS will have this finding. [2] Both processes are thought to arise from endothelial dysfunction, vasoconstriction, breakdown of the blood-brain barrier, and vasogenic edema. [4]

How to diagnose RCVS

The diagnosis can be made clinically as it has been increasingly recognized as a common diagnosis in patients with recurrent thunderclap headaches without any other attributable cause (such as aneurysm, AVM). A non-contrast head CT, CT angiogram, and lumbar puncture may be done to assess for other life-threatening etiologies such as subarachnoid hemorrhage. Direct (femoral) or indirect (MRA, CTA) angiography may confirm the diagnosis by demonstrating vasoconstriction. Vasoconstriction is most typically diffuse, bilateral, and characteristically has a string of beads appearance from segmental narrowing and dilation of cerebral arteries. [2] However, a normal angiogram does not rule out RCVS, as maximum vasoconstriction may not occur up to 16 days after the onset of symptoms. [5] Transcranial doppler may also be useful to monitor disease progression or recurrence, demonstrating increased intracranial velocity which may interestingly persist even after resolution of vasoconstriction on angiogram. [6]

How to treat RCVS

Once the diagnosis of RCVS is made, treatment is generally supportive. In severe cases of RCVS presenting with seizure, coma, and even intracranial hemorrhage, ICU level of care may be necessary. Blood pressure control is similar to stroke management – avoiding hypotension which may precipitate hypoperfusion and watershed infarction. There are no proven therapies for RCVS. Intraarterial vasodilators such as milrinone, nimodipine, epoprostenol, and even balloon angioplasty have been trialed in severe cases without proven success. [2]

Fortunately, the prognosis is fairly positive. Among those who present with focal neurologic deficits, few have residual deficits. Post-partum RCVS may be a risk factor for severe disease. In a case series of 18 patients, four died and five had residual deficits. [7]

Those diagnosed with RCVS should be advised to avoid known triggers (see figure above). In addition, patients should be advised to rest and avoid strenuous activity.

Segmental narrowing and dilation of RCVS [2]

Take-away:

1. Think of RCVS in a middle-aged or postpartum woman presenting with recurrent, thunderclap headache
2. Once the diagnosis of RCVS is made, patients should be counseled to avoid known triggers