Acute Stroke

Presentation

• Sudden numbness or weakness of the face, arms or leg – especially on one side of the body
• Sudden confusion or trouble speaking or understanding speech
• Sudden trouble seeing in one or both eyes
• Sudden trouble walking, dizziness, or loss of balance or coordination
• Sudden severe headache with no known cause

(Society of Neurointerventional Surgery)

Figure 1 : Symptoms of acute stroke
Source - www.wales.nhs.uk

Causes

A stroke occurs due to an interrupted or reduced blood supply to the brain causing brain cell death.

Common causes for strokes are:

• Hyperlipidemia
• Smoking
• Diabetes
• Hypertension
• Atrial fibrillation
• Family history of stroke

(Society of Neurointerventional Surgery)

A stroke may be caused by a blocked artery (ischemic stroke) or bursting of a blood vessel (haemorrhagic stroke). A temporary disruption of blood flow to their brain is known as a transient ischemic attack, or TIA.

 Ischemic stroke

Occurs when the arteries to the brain become narrowed or blocked. It causes severely reduced blood flow. The most common ischemic strokes include:

-               Thrombotic stroke 
           A blood clot forms in one of the arteries that supply blood to the brain. A clot may            be caused by fatty deposits that build up in arteries.

-               Embolic stroke 
          A blood clot or other debris forms away from the brain, commonly in the heart and           it is swept through the bloodstream to lodge in narrower brain arteries.

Haemorrhagic stroke

Haemorrhagic stroke occurs when a blood vessel in your brain leaks or ruptures. Brain haemorrhages can be caused by:

-       Hypertension

-       Over-treatment with anticoagulants

-       Aneurysms

Types of haemorrhagic stroke:

•  Intra-cerebral haemorrhage.
•  Sub-arachnoid haemorrhage

(Mayo Clinic. 2013)

Figure 2 : Hemorrhagic & ischemic strokes

source - www.stemcellmd.org

Investigations

• Computed Axial Tomography (CAT) scan

CAT scan of the brain determines whether the patient is suffering from a stroke. And also it can show whether it is an ischemic stroke or a hemorrhagic stroke. If the CAT scan reveals that there is an ischemic stroke, special CAT scans may be performed to view the arteries and determine the site of the blockage and the way blood flows to the brain. 

• Magnetic Resonance Imaging (MRI) scan

A MRI scan can be also performed instead of a CAT scan. 

(Society of Neurointerventional Surgery)

Stepwise Management

Common treatments for both ischemic and hemorrhagic strokes are,

Anticoagulants / Antiplatelets

Antiplatelet agents such as aspirin and anticoagulants, such as warfarin, interfere with the blood's ability to clot and helps in preventing stroke.  

Antihypertensives

Used to treat high blood pressure. They can lower the blood pressure by opening the blood vessels, decreasing blood volume or decreasing the rate and/or force of heart contraction.

Additionally, when arteries show plaque buildup or blockage, medical procedures may be needed. Such as:

Carotid Endarterectomy 

Also known as carotid artery surgery. In this the blood vessel blockage is surgically removed from the carotid artery.

Figure 3 : Carotid Endarterectomy 

Source - myhealth.alberta.ca

Angioplasty / Stents

Balloon angioplasty and implantable steel screens called stents are used to open up the blocked blood vessel.

(American Heart Association. 2015)

Ischemic Stroke Treatment

• Tissue plasminogen activator

It is given through an IV in the arm. It works by dissolving the clot and improving blood flow to the part of the brain being deprived of blood flow.

• Endovascular Procedures

Removes the blood clot by sending a catheter to the site of the blocked blood vessel in the brain.

Hemorrhagic Stroke Treatment

Endovascular Procedures

Use of a catheter introduced through a major artery in the leg or arm, then guided to the aneurysm or AVM; it then deposits a mechanical agent, such as a coil, to prevent rupture.

Surgical Treatment

A metal clip is placed surgically at the base of the aneurysm to secure it.

(American Heart Association. 2015)

REFERENCES

American Heart Association. 2015. American Heart Association. [ONLINE] Available at: http://www.strokeassociation.org/STROKEORG/AboutStroke/Treatment/Stroke-Treatments UCM 310892_Article.jsp  [Accessed 27th April 15].

Society of Neurointerventional Surgery. (nd.) Society of Neurointerventional Surgery. [ONLINE] Available at: http://www.snisonline.org/stroke [Accessed 27^th April 15].

Mayo Clinic. 2013. Mayo Clinic. [ONLINE] Available at: http://www.mayoclinic.org/diseases-conditions/stroke/symptoms-causes/dxc-20117265  [Accessed 27th April 15].