Narrative review: reversible cerebral vasoconstriction syndromes

Reversible cerebral vasoconstriction syndrome

Reversible cerebral vasoconstriction syndrome (RCVS) is an under-recognised condition. It is characterised by sudden and severe headaches (of "thunderclap" type) associated with multifocal reversible narrowing of the intracranial arteries on neuroradiology. The diagnosis is often established with the resolution of headaches and vasoconstriction. We report two patients with RCVS and review the available literature, to clarify the diagnostic criteria and discuss the treatment options.

Migraine and stroke: current perspectives

OBJECTIVE

The purpose of this article is to review the latest concepts regarding migraine and ischemic stroke. In addition, focal neurological deficits and MRI changes in migraine patients will be reviewed.

METHODS

A PubMed search of neurological literature pertaining to this study was conducted using specific keyword search terms pertaining to migraine and ischemic stroke.

RESULTS

Migraine, especially with aura, is a relative risk factor for stroke. Neuroimaging demonstrates the posterior circulation as being most vulnerable, although the reason for this distribution is unclear. Factors that may contribute to stroke in migraine include changes during cortical spreading depression with hyper- or hypoperfusion of neural tissue, vasospasm and endothelial dysfunction. Estrogen affects migraine expression as well as cerebral circulation, yet most women with migraine without aura are not at increased risk. Co-morbidity with patent foramen ovale can be mechanism of both disorders via presumed lack of filtration of microemboli or toxic substances; however, closure with reversal of right to left shunt seems to be more beneficial for cryptogenic stroke than migraine. Migraine and stroke are found in specific genetic disorders such as CADASIL, HERNS and MELAS giving clues to genetic factors. Stroke associated with migraine treatments such as ergots or triptans is rare, and usually associated with special circumstances such as overuse or concomitant thrombogenic conditions.

CONCLUSION

Although true migrainous infarction is rare, our understanding of the subtle associations between migraine and cerebrovascular behavior is expanding.

Inhibition of cerebral vasoconstriction by dantrolene and nimodipine

INTRODUCTION

Cerebral vasoconstriction is associated with increased cytosolic Ca(2+) concentration in vascular smooth muscle, presumably due to Ca(2+) influx and Ca(2+) release from intracellular stores. We tested the hypothesis that dantrolene (a blocker of Ca(2+)-induced Ca(2+) release from the ryanodine receptor channel on the sarco-endoplasmic reticulum) would potentiate the action of nimodipine (a voltage-dependent L-type Ca(2+) channel blocker, considered standard therapy for SAH) in inhibiting the vasoconstriction of isolated cerebral arteries.

METHOD

Sprague-Dawley rat basilar and femoral arteries were analyzed for ryanodine receptor expression by immunofluorescence and PCR. Vasoconstriction of basilar artery ex vivo was measured in a wire myograph while exposed to serotonin (5-HT) or endothelin-1 (ET-1) in the presence or absence of dantrolene (10-100 muM) and/or nimodipine (30 nM). Femoral artery was examined for comparison.

RESULTS

Basilar and femoral arteries express only the ryanodine receptor 3 (RyR3) isoform. In both basilar and femoral arteries, dantrolene significantly inhibited the constriction to 5-HT, whereas it poorly affected the constriction to ET-1. The inhibitory effect of dantrolene on 5-HT was substantially increased by nimodipine, inducing a 10-fold increase in the 50% effective concentration of 5-HT and a 46% reduction in maximum basilar constriction. In femoral artery, dantrolene modestly affected constriction to phenylephrine and there was no interaction with nimodipine.

CONCLUSION

Dantrolene has synergistic effects with nimodipine against 5-HT-induced vasoconstriction in isolated cerebral arteries. Dantrolene-nimodipine interaction will require testing in a pathophysiological model but might provide treatment for reducing SAH-related vasospasm or other 5-HT-related vasospastic syndromes, such as Call-Fleming syndrome.

Thunderclap headache attributed to reversible cerebral vasoconstriction: view and review

Thunderclap headache attributed to reversible cerebral vasoconstriction (THARCV) is a syndrome observed in a number of reported cases. In this article we reviewed this new headache entity (idiopathic form) using the clinical-radiological findings of 25 reported patients. In this series of patients 72% were women, the mean age at the onset of first headache episode was 39.4 +/- 2.3 years. In addition to the sine qua non condition of being abrupt and severe (thunderclap) at the onset, the headache was usually described as being explosive, excruciating, or crushing. The feature of pulsatility, accompanied or not by nausea was described by 80% of the patients. Forty percent of the cases manifested vomiting and 24% photophobia. Usually the headache was generalized, and in three cases it was unilateral at least at the onset. In 21 of 25 patients (84%) there was at least one recurrence or a sudden increase in the intensity of the headache. A past history of migraine was present in 52% of the patients. Precipitating factors were identified in 56% of the patients. Sexual intercourse was described by six patients. Of the 25 patients with THARCV syndrome studied, 12 (48%) developed focal neurological signs, transitory ischemic attack (n = 1), or ischemic stroke (n = 11, 44%), and two (8%) of them manifested seizures. The THARCV syndrome is a neurological disturbance perhaps more frequent than expected, preferentially affecting middle aged female migraineurs, and having an unpredictable prognosis, either showing a benign course or leading to stroke.

An often unrecognized cause of thunderclap headache: reversible cerebral vasoconstriction syndrome

Thunderclap headache (TCH) can have several causes of which subarachnoid hemorrhage (SAH) is most common and well known. A rare cause of TCH is the reversible cerebral vasoconstriction syndrome (RCVS) which is characterized by a reversible segmental vasoconstriction of the intracranial vessels. We describe two patients with TCH due to RCVS and the probable precipitating factor, namely, cannabis and an anti-migraine drug. In RCVS, cerebrospinal fluid examination is (near) normal, in contrast to SAH and (primary) cerebral vasculitis. Brain MRI may be normal or shows infarction. MRA can demonstrate vasoconstriction of the great arteries, but a normal MRA does not rule out the diagnosis. Caliber changes on cerebral angiography cannot adequately differentiate between RCVS and vasculitis. Calcium-channel antagonists may be a good therapy and repeated transcranial Doppler ultrasonography can be a reliable non-invasive investigation to monitor the effect of treatment and demonstrate reversibility of the vasoconstriction.

Dantrolene mediates vasorelaxation in cerebral vasoconstriction: a case series

INTRODUCTION

Cerebral vasoconstriction syndromes such as vasospasm after subarachnoid hemorrhage (SAH) and trauma, or Call-Fleming syndrome are difficult to treat, and can lead to substantial disability and death. Dantrolene, a ryanodine receptor antagonist, inhibits intracellular calcium release from the sarco-endoplasmic reticulum. We examined the effect of dantrolene on middle cerebral artery (MCA) blood flow velocities as measured by transcranial Doppler (TCD).

METHODS

Three consecutive patients with elevated MCA TCD velocities receiving dantrolene (2.5 mg/kg i.v. q6h) were retrospectively reviewed. Average MCA peak systolic, mean flow velocities, and the pulsatility index (PI) before and after the dantrolene infusion were compared within patients. Systemic physiological parameters (blood pressure, heart rate, central venous pressure, intracranial pressure, body temperature, and cooling water temperature) were retrospectively collected 6 h before and after the dantrolene infusion.

RESULTS

MCA peak systolic velocities (mean +/- SE) for the three patients were 297 +/- 3, 248 +/- 8, and 268 +/- 19 cm/s before dantrolene and 159 +/- 9, 169 +/- 8, and 216 +/- 12 cm/s after dantrolene. Average mean flow velocities showed the same trend. Interestingly, the PI increased slightly from 0.6, 0.52, and 0.67 before dantrolene, to 1.17, 0.71, and 0.77 after dantrolene. Systemic physiological parameters remained stable in all three patients.

CONCLUSION

Dantrolene attenuated cerebral vasoconstriction as measured by TCD without altering systemic physiological parameters. This suggests that intracellular calcium release from ryanodine channels in smooth muscle might play a role in vasospasm. A prospective study is underway to test this hypothesis.

Dantrolene: mechanisms of neuroprotection and possible clinical applications in the neurointensive care unit

Calcium plays a central role in neuronal function and injury. Dantrolene, an inhibitor of the ryanodine receptor, inhibits intracellular calcium release from the sarco-endoplasmic reticulum. We review the available data of dantrolene as a potential neuroprotective agent and briefly summarize its other pharmacologic effects that may have potential applications for patients in the neurointensive care unit (NICU). Areas with the need for continued research are identified.

Postpartum Cervicocephalic Artery Dissection

Background and Purpose— Cervicocephalic artery dissection (CAD) after childbirth is rare. The objective of this study was to determine differences between postpartum and nonpostpartum CAD.

Methods— We compared consecutive patients with postpartum CAD with a control group of women with nonpostpartum CAD.

Results— Of 245 patients with CAD, 102 women <50 years (6 with postpartum CAD and 96 with nonpostpartum CAD) were identified. Vascular risk factors and presenting characteristics did not differ significantly between postpartum CAD and nonpostpartum CAD women. By contrast, patients with postpartum CAD had more often coexisting conditions such as reversible cerebral vasoconstriction syndrome (2 of 6 versus 2 of 96; P =0.017), reversible posterior leukoencephalopathy syndrome (2 of 6 versus one of 96; P =0.009), and subarachnoid hemorrhage without signs of intracranial extension of CAD (2 of 6 versus zero of 96; P =0.003).

Conclusion— CAD and associated conditions should be looked for in women with unusual headache after childbirth.

Bath-Related Thunderclap Headache: A Study of 21 Consecutive Patients

We consecutively recruited 21 patients (all women, mean 54 ± 8 years) with bath-related thunderclap headache (BRTH). Thirteen of them were in menopause, two had just ceased hormonal therapy, and one was at 3 months postpartum. Bathing was the initial trigger for thunderclap headaches in nine patients (43%). Many patients ( n = 15, 71%) had other non-bath-related attacks. Most patients ( n = 18, 86%) reported that the headache occurred immediately when water was sprayed over their body, with warm water (52%) as the most common. During the disease course [mean 14 days (6-34)], the mean number of BRTH was 5.1 ± 3.6 attacks. Nineteen patients (90%) changed bathing habits to prevent attacks. Thirteen patients (62%) had magnetic resonance angiography vasoconstrictions, and two of them (15%) developed reversible posterior encephalopathy. None of the patients without vasoconstrictions had this complication. Nimodipine was effective in stopping further attacks in 84% (16/19) treated patients. No relapse was reported at a mean follow-up of 30 months. BRTH occurred exclusively in women and predominantly in middle age. Deficiency or fluctuation of female sex hormones may play a role. About 60% patients showed cerebral vasospasms, fulfilling the diagnosis of reversible cerebral vasoconstriction syndrome and indicating a risk of posterior encephalopathy.

[A case of reversible cerebral vasoconstriction syndrome (RCVS) triggered by a Chinese herbal medicine]

A 51-year-old woman started taking Chinese medicine containing ephedara herba as a nasal decongestant. One week later, she had three episodes of thunderclap headache, one during defecation and the others while taking a bath. She then had a convulsive seizure upon resolution of the second headache. A cranial CT did not show subarachnoid hemorrhage. Repeated CSF examinations showed neither xanthochromia nor inflammation. Brain diffusion-weighted and FLAIR MR images revealed high intensity lesions in bilateral hemispheres. A cerebral angiography showed multifocal segmental stenosis of bilateral cerebral arteries. Four months later, follow-up angiography showed normalized flow in all cerebral arteries and we gave a diagnosis of reversible vasoconstriction syndrome (RCVS). She has had no symptoms and signs since the third attack of headache. RCVS is an important disease in the differential diagnosis of thunderclap headache without neurological deficit. This is the first report of RCVS triggered by Chinese herbal medicine.

Reversible cerebral vasoconstriction syndrome associated with subarachnoid hemorrhage

INTRODUCTION

Reversible cerebral vasoconstriction syndrome (RCVS) is a rare vasculopathy of unknown etiology. Ischemic stroke and intracerebral hemorrhage are well-documented sequelae, but subarachnoid hemorrhage is an uncommon complication of RCVS.

METHODS AND RESULTS

We report six cases of RCVS associated with subarachnoid hemorrhage. Two cases occurred in postpartum women, two in women with a history of migraines, one in a woman who recently stopped taking her anti-hypertensive medications, and one in a man after sexual intercourse. All six patients presented with the classic thunderclap headache. Two patients experienced generalized tonic-clonic seizures, and two patients had small ischemic infarcts. Segmental vasoconstriction was demonstrated on cerebral angiography in all six cases. Aneurysmal subarachnoid hemorrhage and other etiologies were excluded. Reversibility of the segmental vasoconstriction was confirmed by follow-up angiography in four patients and by transcranial Doppler sonography in two patients. All six patients had an excellent neurological outcome.

CONCLUSIONS

Reversible cerebral vasoconstriction syndrome may be associated with subarachnoid hemorrhage. RCVS should be included in the differential diagnosis of non-aneurysmal subarachnoid hemorrhage.

Clinical spectrum of thunderclap headache

Headaches of the thunderclap variety become severe in intensity within seconds to a minute of onset. Patients with thunderclap headache are to be evaluated in an emergent fashion as many of the underlying causes are associated with significant morbidity and mortality. Although subarachnoid hemorrhage is usually the initial consideration, a multitude of other etiologies have been identified and are discussed herein. In accordance with the increased utilization of cerebral imaging, availability of noninvasive techniques to image the cerebral vasculature and interest in identifying causes of thunderclap headaches, the list of potential causes is growing rapidly. Included in this growth are the reversible cerebral vasoconstriction syndromes, terminology recently introduced to unify several disorders all presenting with thunderclap headache and similar diagnostic findings including reversible vasoconstriction of the intracranial arteries.

Pitfalls in the diagnosis of reversible cerebral vasoconstriction syndrome and primary angiitis of the central nervous system

A case of a 51-year-old woman with reversible cerebral vasoconstriction syndrome (RCVS) without an associative cause is reported. Initially the diagnosis primary angiitis of the central nervous system (PACNS) was considered. Both diagnosis are rare and can mimic each other. Distinction between both can be difficult, but is necessary because of different treatment options. Clinical features and diagnostic assessments to distinguish RCVS from PACNS and the potential pitfalls are discussed.

Cerebral infarction due to vasoconstriction after a hymenoptera stin

A 22-year-old woman developed an anaphylactic reaction after two hornet stings. Left-sided hemiparesis and gaze paresis were revealed after extubation 24 hours later. The vasoconstriction of the right MCA together with hypotension are the suggested pathogenetic determinants of the stroke.