Cerebral Vasoconstriction After Carotid Endarterectomy and the Role of Conventional Cerebral Angiography

PRACTICAL IMPLICATIONS

Hemorrhage after carotid revascularization should prompt detailed vascular imaging such as serial conventional angiograms.

Carotid endarterectomy (CEA) and carotid artery stenting are established cerebrovascular procedures to reduce the risk of stroke. Complications include stroke, myocardial infarction, and death. A delayed complication after carotid revascularization is cerebral hyperperfusion syndrome (CHS), which can manifest as intracerebral hemorrhage (ICH).¹ A less common delayed complication of carotid revascularization procedures is reversible cerebral vasoconstriction syndrome (RCVS).

RCVS typically presents with thunderclap headaches, with or without focal neurologic deficits, seizures, and radiographic evidence of focal vasoconstriction in multiple cerebrovascular territories, which generally resolve spontaneously within 3 months.² The pathophysiology remains to be defined; however, it is postulated that there is a dysregulation of the cerebral arterial tone resulting from excess sympathetic tone associated with spontaneous neuronal or vascular-driven effect.³ In contrast to CHS, which often presents with ICH, RCVS may present with convexity subarachnoid hemorrhage (cSAH).⁴

We describe a case of RCVS associated with CEA and cSAH. The case demonstrates the need for proper vascular imaging because otherwise the diagnosis may be missed.

Case

A 58-year-old right-handed woman has a history of >80% symptomatic left carotid artery occlusive disease with left retinal ischemia and controlled hypertension. She was on lisinopril for blood pressure control and aspirin as an antithrombotic. She developed severe headache on postoperative day 2 after CEA, which was performed under general anesthesia without immediate complication. She had sudden, brief periods of incoordination when attempting to walk, resulting in near falls. She had no history of headaches.

Initial CT of the head revealed a left frontal extra-axial slightly hyperdense lesion consistent with subarachnoid hemorrhage (SAH). Her MRI brain revealed a hyperintensity within the extra-axial space overlying the left frontal lobe and susceptibility artifact on gradient echo sequences in the subarachnoid space adjacent to the left frontal lobe and leptomeningeal enhancement (figure, A). CT angiography of the head did not show evidence for vasoconstriction. Conventional cerebral angiography revealed multiple foci of vasoconstriction in the left anterior circulation (figure, B). The CSF analysis did not reveal any significant elevation in white blood cell count or protein. The patient did not use cannabinoids and was not on any selective serotonin reuptake inhibitors or migraine abortive agents, which can be associated with cerebral vasoconstriction. Postoperatively, the patient was normotensive.

Figure. MRI of the Brain and Conventional Angiography of the Cerebral Vasculature.

(A) MRI of the brain with extra-axial restricted diffusion, postcontrast enhancement, and susceptibility artifact suggesting hemorrhage. (B) Initial foci of vasoconstriction in the left anterior circulation. (C) Delayed complete resolution of vasoconstriction.

The association between CEA and RCVS was not evident to the treatment team at the time, and therefore, intra-arterial (IA) or systemic calcium channel blocker (CCB) therapy was not administered. The headache was controlled with analgesics. The patient fully recovered and was discharged.

Two months later, repeat conventional angiography revealed complete resolution of the vasoconstriction (figure, C), leading to the diagnosis of RCVS based on the criteria introduced by Calabrese et al.³

Discussion

We describe a patient with reversible cerebral vasoconstriction and SAH after CEA for symptomatic carotid artery stenosis. Clinical findings, cSAH, and cerebral vasoconstriction led to a diagnosis of RCVS in the absence of any other apparent cause.

The critical diagnostic test was conventional cerebral angiography, demonstrating multifocal vasoconstriction with subsequent resolution. Had this test not been performed, the diagnosis may have been missed. Other vascular imaging modalities including magnetic resonance angiography (MRA) and computed tomography angiography (CTA) are limited in resolution to visualize distal arteries. High-resolution magnetic resonance vessel wall imaging is an emerging modality but is not widely available. Transcranial Doppler may reveal dynamic changes but has low sensitivity for early or distal vasoconstriction.

Earlier recognition of RCVS after CEA could have resulted in the use of IA CCB, followed by oral CCB to reverse vasoconstriction; however, such therapy remains untested in a larger scale study.³

There are 5 previously reported cases of RCVS after CEA for symptomatic carotid stenosis and 5 cases of RCVS after CEA for asymptomatic disease (table).^5–7 Symptom onset timing after surgery averaged 7 days for symptomatic stenosis and 4.4 days for asymptomatic stenosis. Three patients received IA therapy, all of whom had asymptomatic disease before CEA and >80% stenosis. One particularly interesting patient developed RCVS after both right and left CEA carried out 1 year apart.

Table.

Details of the Studies of Reversible Cerebral Vasoconstriction Syndrome After Carotid Endarterectomy of Symptomatic and Asymptomatic Carotid Stenosis

In both groups, the most common symptom was headache. Eight of 10 patients had neurologic deficits such as numbness, weakness, incoordination, or aphasia. Hemorrhage occurred in 3 patients, all with ICH and convexity SAH.

RCVS is a rare complication after CEA and may be underreported because of its varying clinical presentation and, in some cases, limited subsequent diagnostic cerebrovascular study. In our case, had repeated conventional cerebral angiography not been carried out, the diagnosis may have been missed. Indications for conventional cerebral angiography may include SAH or lobar hemorrhage after carotid revascularization.

Appendix. Authors

Study Funding

No targeted funding reported.

Disclosure

The authors report no disclosures relevant to the manuscript. Full disclosure form information provided by the authors is available with the full text of this article at Neurology.org/cp.