Convexity subarachnoid haemorrhage secondary to internal carotid stenosis: an indication for revascularisation

Area of Science:

• Neurology
• Vascular Surgery
• Neurosurgery

Background:

• Carotid artery stenosis (CAS) is a major cause of stroke, with treatment guidelines established for symptomatic cases.
• The management of asymptomatic CAS remains controversial, posing a clinical challenge.
• An aging population contributes to the increasing prevalence of CAS.

Observation:

• A 78-year-old woman presented with convexity subarachnoid hemorrhage (cSAH) due to previously undiagnosed high-grade internal carotid artery stenosis.
• Two months post-hemorrhage, she experienced an atherothrombotic ischemic stroke, necessitating surgical intervention.
• Post-endarterectomy, the patient developed reperfusion syndrome, indicating compromised cerebral collateral circulation.

Findings:

• Transcranial Doppler studies revealed impaired cerebral vasoreactivity, suggesting exhausted collateral pathways.
• The patient's clinical course, including cSAH and subsequent ischemic stroke, highlights the potential severity of asymptomatic high-grade CAS.
• Exhausted collaterals were identified as the underlying mechanism for both cSAH and reperfusion syndrome.

Implications:

• Convexity subarachnoid hemorrhage secondary to high-grade internal carotid artery stenosis may serve as a critical marker for elevated stroke risk.
• Revascularization therapy, such as endarterectomy, should be strongly considered in patients with high-grade CAS presenting with cSAH.
• Further research is warranted to refine treatment strategies for asymptomatic carotid artery stenosis, particularly in high-risk presentations.