Cerebrovascular accident (CVA) or stroke is the condition in which blood flow to the brain is obstructed and hence there is a rapid loss of brain function. It can be caused by rupture of an artery in the brain or the blocking of a blood vessel by a clot. It is the second leading cause of death worldwide after heart diseases.
There are two main types of stroke:
This can occur when blood flow to a part of the brain is interrupted leading to brain tissue damage in that area. This can occur due to blocking of a blood vessel by a clot formed locally (thrombosis), an embolus (it is a free-floating clot formed somewhere else) causing the obstruction (embolism), decrease in blood flow due to shock (systemic hypoperfusion) or a blood clot in the dural venous sinuses draining blood from the brain (venous thrombosis).
A hemorrhagic stroke can occur when a blood vessel on the brain's surface bursts and bleeds in between the brain and skull (subarachnoid haemorrhage) or when a there is a rupture and bleeding inside the brain (cerebral haemorrhage).
Apart from these two, there is the silent stroke or transient ischemic attack (TIA) occurs when blood flow to part of the brain is blocked temporarily.
It is important to be able to recognise the signs and symptoms of a stroke as it can save life and lead to early recovery.