Stroke

Question 1

What is a cerebrovascular accident CVA?

Answer 1

Stroke- acute onset of focal neurological symptoms and signs due to disruption of blood supply. You can tell roughly the area of brain affected by the signs

Question 2

What are the major consequences of stroke in the community?

Answer 2

Loss of independence, burden to family, loss of earning

Question 3

What is the tend of incidence and prevalence in stroke?

Answer 3

Fewer people are dying from stroke- the first stroke rarely kills but 2 in 3 leave hospital with a disability
Incidence and prevalence increasing

Question 4

What is a haemorrhagic stroke?

Answer 4

Bleed into the neurological tissue of the brain

Question 5

What is the greatest risk factor for haemorrhagic stroke?

Give 3 other risk factors

Answer 5

Hypertension
Other risk factors include weakened blood vessel walls due to abnormalities like aneurysm or arteriovenous malformation (AVM) or infamation of the vessel wall eg vasculitis

Question 6

What is an ischemic stroke?

Answer 6

Death of tissue due to lack of perfusion

Question 7

What are the 3 causes of ischemic stroke?

Answer 7

Thrombotic- clot blocking artery at the site of occlusion
Embolism- clot blocking artery has travelled from a distant site to the artery it is occluding (often more proximal arteries or the heart
Hypoperfusion- where demand outstrips supply as there is reduced blood flow due to a stenosed artery

Question 8

How long before the brain begins to die through lack of perfusion?

Answer 8

3-4 minutes

Question 9

What are the general risk factors fir stroke?

Answer 9

NON MODIFIABLE: age, gender, race (S Asians), family history, previous stroke
MODIFIABLE: Hypertension, hyperlipidaemia, smoking, history of TIA, AF, diabetes, heart failure, alcohol excess,obesity, lack of activity, deprivation

Question 10

What is a TIA?

Answer 10

Transient ischemic attack- atery is temporarily blocked => transient symptoms eg limb weakness, impaired speech, diziness
The endothilium dissolves the clot- no long term damage

Question 11

What can be done to prevent stroke?

Answer 11

Lower BP
Stop smoking (this doubles the risk of ischemic stroke)
Hyperlipideamia: Statin is recommended for all ischemic strokes but not haemorrhagic

Question 12

What are the rare causes of stroke in younger people?

Answer 12

Homocysteinemia- high levels of homocysteine
Vasculitis
Antiphospholipid antibody syndrome
Protein S, C or antithrombin deficiency
Paradoxical embolism- venous clot travels into the arterial system via a hole in the heart
Genetic factor 5 leiden mutations or common prothrombin mutation
Cardioembolic; Mural thrombi, infective endocarditis, myoxoma
Cervical artery dissection

Question 13

What conditions can mimic a stroke?

Answer 13

Hypoglycaemia, seizure, migraine, brain tumours, functional hemiparesis (pretending to have a sroke)

Question 14

What should you examine if you suspect a stroke?

Answer 14

General exam, cardio exam and a neurological exam

Question 15

How can you differentiate between ischemic and haemorrhagic stroke?

Answer 15

Brain imaging

CT brain +/- angiography

Question 16

What images are used for haemorrhagic and ischemiac stroke?

Answer 16

Ischemic = MRI with diffusion weighted imaging
Haemorrhagic = MRI with susceptibility weighted imagind

Question 17

If you identify the stroke as ischemic, which tests can help you determine the cause?

Answer 17

Blood tests: glucose, lipids, thrombophilia
?Atheroembolism = platelet rich clot, will infarct on te same side as the coronary artery. => Carotid scanning, CT angiography of aortic arch
?Cardioembolism = fibrin rich clot which will infarct on multiple areas of the brain. => Ambulatory ECG for paroxismal arrhythmias, echocardiogram

Question 18

WHat commonly forms a mural thrombus?

Answer 18

AF

Question 19

If you identify the stroke as haemorrhagic, you need to identify the cause of the bleed. What commonly causes a bleed deep in the brain of older patients?

Answer 19

hypertension

Question 20

If you identify the stroke as haemorrhagic, you need to identify the cause of the bleed. WHat if the patient is young, normatensive and the haemorrhage is lobar or superficial?

Answer 20

Aneurysm

Question 21

If you identify the stroke as haemorrhagic, you need to identify the cause of the bleed. What of there are multiple haemorrhages?

Answer 21

Vasculitis
Moya moya disease
Cerebral amyloid angiopathy

Question 22

In ischemic strokes what is the time period for thrombolysis and thrombectomy?

Answer 22

Thrombolysis <4.5 hours

Thrombectmy <6 hours after starting thrombolysis

Question 23

What drug is used for thrombolysis?

Answer 23

tPA- tissue plasminogen activator

Despite the risk of haemorrhage, functional outcomes are better if you thrombolyse- SITS-MOST trial

Question 24

What is a thrombectomy?

Answer 24

Putting a wire into the brain and putting mesh around the clot to remove it

Question 25

When can a thrombectomy be done?

Answer 25

If the clot is within a proximal artery

Question 26

How can future strokes be prevented if the cause was atheroembolic or thrombotic?

Answer 26

``` Antiplatelets Statins Diabetes managements hypertension management Lifestyle advice ```

Question 27

How can future strokes be prevented if the cause was AF?

Answer 27

Anticoagulate | Warfrin or rivaroxaban, dabigatran, apixaban

Question 28

When is surgery indicated in stroke?

Answer 28

Saving a life Haematoma evacuation relief of raised intracranial pressure Carotid endartectomy

Question 29

What is the risk of stroke following a TIA in a month and within 5 years?

Answer 29

Month = 11-15% | 5 years = 24-29%