8th August 2024

Haemorrhagic stroke

Aetiology and pathophysiology of haemorrhagic stroke

Approximately 20% of strokes are haemorrhagic.

The biggest risk factors are increasing age, hypertension, and use of antiplatelets or anticoagulants. Other risk factors include male sex, heavy alcohol use, stimulant drug use (cocaine), vascular malformations and cerebral malignancy, cerebral amyloid angiopathy (CAA), bleeding disorders, cerebral vasculitis and increased aneurysm risk (e.g. in connective tissue diseases or autosomal dominant polycystic kidney disease).

Haemorrhagic stroke may occur due to:

• Spontaneous intracerebral haemorrhage, risk factors for which are listed above, but most common aetiologies are hypertensive (resulting small vessel disease affecting deep perforating vessels leads to haemorrhage within the deep structures of the brain, such as the basal ganglia) and CAA (deposition of amyloid beta-peptide deposits in blood vessels results in lobar haemorrhage affecting cortical vessels. CT may demonstrate typical ‘finger-like’ projections and subarachnoid extension).
• Subarachnoid haemorrhage (SAH): mostly due to aneurysm rupture.

Pathology due to traumatic haemorrhage (e.g. subdural or extradural haematoma) is not usually considered a stroke.

Presentation and management of haemorrhagic stroke

The presentation is similar to ischaemic stroke. Clues that a stroke may be haemorrhagic include meningism, severe headache, reduced or progressive loss of consciousness and seizures.

Initial assessment is the same as for ischaemic stroke, including the importance of swift diagnosis and management. Specific considerations for haemorrhagic stroke include:

• Assessment: haemorrhage will usually be seen on CT
• Initial treatment:
  • Rapid blood pressure control using IV labetalol, target 140 mmHg systolic
  • Rapid reversal of anticoagulation; not for aspirin or other antiplatelets
  • Discuss with neurosurgery
• SAH: additionally treated with nimodipine PO/NG (nasogastric) to reduce vasospasm; ultimately requires neurosurgical management with endovascular coiling, if there is an appropriate aneurysm target, to prevent re-bleeding
• Identifying the cause:
  • MRI may demonstrate an arteriovenous malformation (AVM); microbleeds suggest CAA
  • SAH: cerebral angiography (CTA, MRA [MR angiography] or digital subtraction angiography) to identify aneurysms
• Secondary prevention is with adequate control of hypertension and other risk factors. Statins are contra-indicated post haemorrhagic stroke

Image Source: Wikimedia Commons (2008). Intracerebral, Licensed under a creative commons licence. Available for free at: https://commons.wikimedia.org/wiki/File:Intracerebral.jpg (Accessed: 16 January 2024)

Image Source: Wikimedia Commons (2006). Subarachnoid haemorrhage, Licensed under a creative commons licence. Available for free at: https://commons.wikimedia.org/wiki/File:Subarachnoid_haemorrhage.jpg (Accessed: 16 January 2024)

Image Source: Wikimedia Commons (2016). Trauma subdural arrows, Licensed under a creative commons licence. Available for free at: https://commons.wikimedia.org/wiki/File:Trauma_subdural_arrows.jpg (Accessed: 16 January 2024)

Image Source: Wikimedia Commons (2011). 13049 2011 Article 474 Fig2 HTML, Licensed under a creative commons licence. Available for free at: https://commons.wikimedia.org/wiki/File:13049_2011_Article_474_Fig2_HTML.webp (Accessed: 16 January 2024)