Table 1 Underlying mechanisms of haemorrhagic and ischaemic stroke 3

Thrombus - from a ulcerated plaque in the carotid artery

Hypertension is the commonest - causing weakness of the vessel wall

Cardioembolism from Atrial fibrillation (AF)

Amyloid angiopathy

Large vessel atherosclerosis causing a stroke by occlusion

Use of sympathomimetic drugs such as cocaine causing transient hypertension

Small deep perforating vessel arthrosclerosis causing lacunar stroke

Congenital Arterio-venous malformations, aneurysms

A venous clot, causing paradoxical embolism through a patent foramen ovale (PFO)

Uncommon such as tumours, vasculitis, bleeding diathesis and use of anticoagulants

Vasospasm of structurally normal vessels (e.g. sympathomimetic drug use)

Hypercoagulable state, operating with any of these mechanisms or independently