What is a Stroke

When blood flow to an area of the brain is cut off, brain cells in that area are deprived of oxygen and die. Depending on the area affected various permanent disability like paralysis of a limb, loss of memory or inability to speak can occur. If the area affected is large the person will have severe disability affecting many parts of the body. A massive stroke can also be fatal.

Stroke Association UK reports that in the UK one stroke occurs every 3 minutes and 27 seconds. In USA it is the fifth leading cause of death. However no two strokes are the same. Recovery from a stroke differs from person to person. The ability to recover from a stroke depends on the severity of the stroke and how quickly you get treated. The quicker the treatment the better the recovery. Because every stroke is different, there is no set pattern for recovery.

Symptoms of stroke
• The face may be distorted and droop on one side. The person may not be able to smile.
• Significant weakness of one arm. When asked to raise both arms together, one arm keeps dropping or not able to raise that arm.
• Speech may be altered or slurred.

Other less common symptoms may be:
• Sudden severe headache that cannot be controlled by a pill.
• Sudden blurring of vision
• Suddenly becoming violent or confused
• Numbness of a limb or part of the face with weakness
• Sudden dizziness or becoming unconscious

Any one of the signs above when present is probably a stroke and the person will need emergency medical treatment. Get them to the nearest hospital treating strokes. Make sure the hospital has access for an emergency scan. The sooner the diagnosis is confirmed and treatment begun the better the result.

A stroke is a medical emergency and needs immediate medical attention.

Types of Stroke:
Ischaemic Stroke: When the blood vessel supplying an area of the brain is blocked by a cerebral embolism or a build-up of fatty plaque within the vessel wall, the blood supply to the area gets blocked and an “Ischaemic Stroke” results.

Haemorrhagic Stroke:When a vessel supplying an area of brain ruptures leaking blood (burst aneurysm), the area is deprived of oxygen and “Haemorrhagic Stroke” results. Stroke can also result when there is pressure on an area of brain by a bulging blood vessel (aneurysm).

Although a majority of stroke is an Ischaemic Stroke, if a haemorrhagic stroke is treated as you would an ischaemic stroke the result would be catastrophic as more blood would leak in to the area, causing more damage to the brain cells. According to the American Stroke Association 13% of strokes are haemorrhagic strokes.

Therefore, before commencing treatment the type of stroke must be established.

Investigation:

Scan: To distinguish between Ischaemic and haemorrhagic stroke it is necessary to have a brain scan. The scan will confirm the type of stroke.

Other Tests: Routine general examination of the patient must exclude atrial fibrillation as this may be the cause for an embolus. Blood tests must also check for high cholesterol.

Treatment
Once the type of stroke is confirmed, treatment should be started without delay. Effective and early treatment can prevent long-term disability. Treatment is usually non-surgical but some may need surgery.

Non-Surgical Treatment:
The aim of treatment in ischaemic stroke is to re-establish blood supply to the area of brain deprived of blood flow as soon as possible. This usually means getting rid of a blood clot that is obstructing the vessel.

Alteplase also known as tPA is an injection that is given to dissolve the clot (thrombolysis). However, for it to be effective it must be given within 4 to 5 hours of a stroke. It is estimated that 1 in 7 patients benefit by this drug. As the majority of stroke is caused by a blood clot Alteplase has become a very useful drug in treating stroke.

Blood thinning Drugs: In ischaemic stroke drugs like aspirin and clopidogrel should be considered.

Other Drugs: To prevent further clots developing anticoagulants like heparin and warfarin may be given for varied lengths of time. Anticoagulants are particularly useful when you have an atrial fibrillation which could contribute to an embolus forming or when the patient is at risk of developing (or have had) a DVT.

Statins: If the levels of triglycerides and cholesterol are high the patient should be advised Statins to lower the level. High cholesterol usually encourages the build up of lipid plaque within the lumen affecting blood flow to the brain (or heart).

Antihypertensives: In haemorrhagic stroke high blood pressure must be controlled as it can cause an aneurysm in the brain to leak. If the patient is on anticoagulants, this must be stopped immediately.

Surgical Treatment: Surgery in Stroke may be undertaken for a variety of reasons. The type of procedure will depend on the cause and type of stroke.

Carotid endarterectomy: If the Ischaemic Stroke is caused by narrowing of the carotid artery (caused by deposition of plaque), the patient will require a surgical procedure to remove it (Carotid endarterectomy).

In Hemorrhagic Stroke the types of surgery done will include clipping of aneurysm, coil embolization, and repair of arteriovenous malformation (AVM).

Clipping of Aneurysm, Coil Embolization and Repair of Arterio Venous Malformation:
Many of these procedures require opening the skull. There is now an attempt to treat some of these endoscopically. This is done by using a catheter introduced through the femoral artery in the thigh to reach the affected area in the brain.
In the case of an aneurysm, stroke may result either from blood leaking from the aneurysm or by direct pressure of an expanding aneurysm on the brain cells.

The treatment here would be to clip the aneurysm where it arises from the main vessel to block the blood entering it. This surgery helps prevent further blood leaking from the aneurysm. It can also help prevent an aneurysm from bursting again. During the procedure, the surgeon will place a tiny clamp at the base of the aneurysm.

Coil embolization is a less complex procedure for treating an aneurysm. The surgeon will insert a catheter into the femoral artery in the groin. The catheter is then threaded to the site of the aneurysm. Then, a tiny coil will be pushed through the tube into the aneurysm. The coil will cause a blood clot to form, which will block blood flow through the aneurysm and prevent it from leaking blood or bursting again.

Arteriovenous Malformation Repair: AVM is a tangle of malformed vessels where arteries and veins are connected in an abnormal manner. This may either rupture leaking blood in to the brain or by its bulge cause pressure on the brain. Here the AVM will need a repair. There are various ways of repairing an AVM. The methods include surgery toremove them, radiation to shrink them or injecting a substance to block them.

Conclusion: Stroke is a major cause of disability and is now considered as the 5th leading cause of death. The majority of strokes are ischaemic in type and can be treated non surgically. The sooner the treatment is started the better the recovery.

To identify and treat stroke remember – “FAST”.
F = Facial weakness, A = Arm weakness, S = Speech altered and T= Timing of treatment determines speed of recovery.

Ref: NHS Choice; American Stroke Association; National Heart Lung and Blood Institute

Hi Badri
Thanks for the review of Stroke one of the common medical problems every of us face. We know that despite all modern development in the field of medicine, we are not able to do much for stroke patients. The deeper we dwell in the subject, more depressed we become.
As you correctly mentioned hypertension is the most important factor in the causation of this malady. A few random points I want to make for the sake of junior colleagues.
Hypertension is common in patients admitted with an acute stroke, and a transient blood pressure rise can be found also in previously normotensive patients, whereas in patients with haemorrhagic stroke hypertension in the acute phase is more severe than the usual blood pressure elevation.
The appropriate management of raised blood pressure at stroke onset remains an unsolved question. In fact, blood pressure may decline spontaneously and unpredictably without intervening medications. Furthermore, the incorrect use of antihypertensive drugs in acute stroke may reduce the pressure-dependent cerebral perfusion to the ischemic penumbra, the area surrounding the ischemic necrotic core perfused by collaterals at low flow, and therefore may worsen cerebral damage.
We have noted in our practice that there are so many patients under our care who show much variability or instability in the BP recordings despite two or three drugs. Such persons who show this type of instability are prone to chronic repeated small stroke like events leading to brain atrophy, subcortical ischemic lesions and cognitive impairment. Calcium channel blockers are said to be better for these patients.
It has been known for years that blood pressure at night is typically lower than blood pressure during the day. There is a somewhat arbitrary cut-off of about 10%. If your blood pressure declines less than 10% during the night compared with what it was during the day, you are defined as a non-dipper. There is a fair amount of data that have shown that if you are a non-dipper or if your blood pressure at night remains elevated, the risks for subsequent cardiovascular disease and renal disease are higher. These variability of BP can be identified and treated only by ambulatory BP measuring devices.
Another category of patients who have risk of stroke is persons who have obstructive sleep apnoea. Experts on sleep apnoea have data showing that if you fix the sleep apnoea, you can restore dipping status in many cases, although not all of them.
The significance and best management of hypertension observed during the first hours after stroke onset are still a matter of debate. Recent guidelines recommend clinical trials to ascertain whether antihypertensive therapy in the acute phase of stroke is beneficial. This review summarizes previous reports on blood pressure management during the first 72 hours after an acute ischemic stroke and shows that a large number of papers published in the past 20 years failed to convince that early use of antihypertensives in unselected patients with acute ischemic stroke is beneficial. The authors stress that only blood pressure values repeatedly higher than 220/120 mm Hg should be gradually lowered and kept in the range of 180-220 mm Hg systolic and 100-120 mm Hg diastolic. (Ref: http://www.medscape.com/viewarticle/473113).

UA Mohammed

Mohammed,
Thank you for your feedback on this important topic. Hypertension is an important topic on its own. It is a vast subject where research has been a continuous process. As you rightly point out, it can affect the heart, brain, kidney or any other system. What is important here (stroke) is that, if you are dealing with hemorrhagic stroke, hypertension can make things worse and will need careful monitoring. It does not mean you should lower the BP drastically.

It is important to find out the type of stroke you are dealing with before starting treatment.