Thrombotic Diseases Flashcards
Define stroke
/Is a neurological deficit of cerebrovascular cause that persists beyond 24 hours or interrupted by death within 24 hours
When does stroke occur
when there is a rapid death of brain tissue due to a disturbance in blood supply
What is a major differentiating factor between a stroke and a TIA
Time frame - 24 hours
Stroke beyond 24hrs
Tia resolved within 24 hrs
Risk factors for stroke
Inactivity Previous stroke and tia Obesity/unhealthy etc Heart disease / high Bp Smoking Diabetes Age/ family history Oral contraception
What are the carotid arteries
Anterior supply for front and middle regions of brain
What are vertebral arteries
Posterior supply for brain stem and rear regions of brain
What are the 2 types of stroke
Ischamic
Haemorrhagic
Subtypes of ischaemic stroke?
- thrombosis
- embolism
- atrial fibrillation
- endocarditis
What is thrombosis cause ischaemic stroke?
Associated with the large and small arteries - carotid, vertebral, basilar
Damages caused by an atherosclerotic plaque rupture leading to thrombosis, this interrupts the blood supply and then nutrients such as oxygen and glucose cannot get to the neurons. There is a rapid death of brain tissue leading to loss of function
What is the embolism cause of ischaemic stroke ?
Caused by conditions that form clots in the left ventricle of the heart such as a heart attack or congestive heart failure.
The heart is the most common source of embolism to the brain so then these clots break off and go to the brain from upstream arteries
It is basically as a result of a low ejection fraction in the heart in these conditions which activate a clotting cascade and therefore clot —> embolism
Most common type of stroke
Ischaemic
What is the atrial fibrillation cause of ischaemic stroke?
During atrial fib -the left atrium is less effective in the ejection of blood which then lead to blood stasis in the left atrial Appendage which leads to clots and therefore the Emboli can break off and cause a stroke in the brain
What is the endocarditis cause of stroke?
There can be fungal or bacterial growth in the heart valves which then form clumps or vegetation which can break off into emboli and travel to the brain
2 types of haemorrhagic stroke?
Intracerebral
Subarachnoid
What is intracerebral stroke and it’s cause?
Bleeding Within brain - due to hypertension, trauma, bleeding disorders or vascular defects
Arteriovenous malformation - the feeder artery to NIDUS lead to collection vein
There is a highBP in AVM which causes rupture and bleeding - causes haematoma which can compress, rupture and damage neurone - irreversible damage
What is subarachnoid stroke and risk factors
On surface of brain - mainly due to aneurism rupture mainly occurring in circle of Willis
Risk factors are smoking,alcohol, hypertension, genetics, drug abuse and drugs eg anticoagulants