Stroke

What a stroke is and why the heart is involved

A stroke happens when the blood supply reaching part of the brain is cut off. It requires immediate and urgent treatment to minimise the damage to the brain and to allow for a better prognosis.

The brain relies on oxygenated blood to work properly. Any restriction or blockage to that supply causes brain cells to die, which leads to the loss of brain function. In the long term, a stroke can lead to brain damage, severe disability and even death if it is not treated immediately.

Although the damage happens in the brain, the causes usually sit in the heart and the blood vessels, which is why stroke is treated as part of cardiovascular disease. Stroke prevention is one of the areas Dr Jogiya specialises in, and his role is to find and treat the heart and circulation problems that make a stroke more likely in the first place.

The two main types of stroke

There are two main types of stroke, and they affect the blood flow to the brain in different ways. Which type has occurred matters, because it changes how the stroke is treated.

A clot does not always stay where it forms. When a clot, or thrombus, breaks off from the original vessel and moves in the blood it is known as an embolus. It can then cause a blockage somewhere else, in another area of the heart, in the lungs as a pulmonary embolism, or in the brain, where it causes the ischaemic type of stroke described below, also known as a cerebral infarction.

• Ischaemic stroke. This is when the blood supply is stopped or reduced because of a blood clot, which accounts for around 85% of strokes in the UK. The clots are usually formed due to coronary artery disease, with clots formed through the process of atherosclerosis.
• Haemorrhagic stroke. This type, accounting for around 15% of all strokes, occurs when blood vessels supplying blood to the brain become weakened and burst or rupture. Those vessels can be affected by atherosclerosis, or they can become weaker with age and with other co-morbidities such as diabetes.

Conditions that raise the risk of a stroke

Certain conditions increase the risk of a stroke occurring. Most of them can be treated, which is why they take up so much of a cardiology assessment.

Angina is worth mentioning here too. It can be a warning that you may be at risk of a heart attack or a stroke, and its symptoms can be controlled with treatment and lifestyle changes.

• High blood pressure. This impacts the walls of the blood vessels and weakens them, adding increased strain, which can lead to a rupture. Sustained hypertension also raises the risk of heart disease, heart attacks, heart failure, peripheral artery disease, aortic aneurysms, kidney failure and vascular dementia.
• High cholesterol. This increases the fatty deposits inside the arteries, leading to atherosclerosis and plaque build-up which aids in forming a clot.
• Atrial fibrillation. In AF the blood is not pumped properly and so can stagnate in the heart, causing clots to form which can travel to the brain and other organs. AF is one of the most common heart rhythm issues and around 1.7 million people in the UK have been diagnosed with it.
• Diabetes. Diabetes increases the risk of blood vessels becoming brittle and weak, making them stiffer over time, which can cause damage and can also burst or cause a rupture.

How your risk is assessed

The tests below do not look for a stroke. They look at the heart and the circulation for the treatable conditions above, and for anything that would change how those conditions are managed. Which of them is arranged depends on your history and your symptoms.

Blood pressure is a measurement of the pressure at which blood flows through blood vessels, and two numbers are recorded, a systolic and a diastolic reading, both in millimetres of mercury (mmHg). The British Heart Foundation puts the normal range at 90/60mmHg to 130/85mmHg.

Measurements of 140/90mmHg or higher when checked by a healthcare professional are classed as hypertensive, while people over 80 have a different target, below 150/90mmHg in clinic. Readings between 130/85mmHg and 139/89mmHg are what the British Heart Foundation calls pre-hypertension, raised but not yet diagnosed as high blood pressure.

• 12 lead ECG. Heart rhythm issues such as atrial fibrillation are diagnosed through an ECG, which records the electrical activity of the heart over several seconds.
• ECG monitor. A prolonged ECG recording worn over a longer period is used when a rhythm comes and goes, because a short recording in clinic can easily miss an intermittent one.
• Blood pressure monitor. An ambulatory blood pressure monitor records measurements throughout the day and calculates an average blood pressure reading, which helps separate sustained hypertension from a single high reading in clinic.
• Blood tests. These help build the wider picture of your cardiovascular risk, and a lipid panel is where your cholesterol levels are measured.
• Echocardiogram. An ultrasound scan of the heart shows its structure and how effectively it is pumping.

How a stroke is treated

Treatments for a stroke depend on the factors that caused the stroke, and on the timeline of events that have happened since the stroke. This is why speed matters so much and why a stroke is always treated as an emergency rather than something to be assessed the next day.

If a stroke has been caused by a blood clot, in other words an ischaemic stroke, then a procedure known as a thrombolysis will need to be performed to break the clot. Sometimes a clot might need to be surgically removed instead. If the cause of the stroke was haemorrhagic, the bleed needs to be stopped.

Other medications are then used to reduce the risk of it happening again, including blood thinners, cholesterol medication and blood pressure medicines.

Some people may need periods of rehabilitation following their stroke to regain their strength and body function. This will vary from person to person depending on the severity of the stroke and the further treatment given. Some people might not recover fully, but they can still regain some strength to perform normal daily tasks.

Reducing the risk of a stroke

Because most of the conditions that lead to a stroke can be treated, there is a lot that can be done to lower the risk. People who have already had a stroke are at higher risk of having another one without any changes to their diet, alcohol intake and exercise capability, so prevention matters just as much after a stroke as before one.

Lifestyle choices can always help to manage blood pressure. Increasing exercise, losing weight, reducing stress and avoiding coffee or alcohol can all help to reduce and manage your blood pressure. If lifestyle changes do not make a difference, then medication can be given to help control blood pressure levels, and different medicines work for different people depending on age, ethnicity and average overall blood pressure levels.

There are some things you cannot control that contribute to higher blood pressure levels, such as your ethnic background and socioeconomic status. The NHS lists a Black African, Black Caribbean or South Asian background among the things that raise your risk, and high blood pressure is more common in more deprived areas.

Controlling cholesterol levels usually requires medication alongside a controlled diet. Where atrial fibrillation is the concern, treatment begins with medication to control the heart rate and regulate heart function, and patients diagnosed with AF may often also be commenced on blood thinning medication to prevent the risks of stroke or other blood clot formations in the heart. Other treatments can include DC cardioversion and ablation procedures to try to reset the heart to its natural rhythm.

When to get help

A stroke is a medical emergency. If you think that you or someone with you may be having a stroke, call 999 immediately and do not wait to see whether it settles. Immediate treatment is what minimises the damage to the brain and allows for a better prognosis.

The signs come on suddenly, and the way to recognise them is the word FAST, which is what NHS advice uses.

Call 999 as well for chest pain that is severe, for chest pain that comes with sweating, sickness or breathlessness, or if someone collapses.

If you are not in an emergency but you have been told you have high blood pressure, high cholesterol, atrial fibrillation or diabetes, or a stroke or heart attack runs in your family, an assessment is worth arranging. A consultation with Dr Jogiya begins with a detailed discussion of your symptoms, lifestyle and medical history, followed by an examination focused on the cardiovascular system, and the tests that are appropriate for you are decided from there. You can contact the practice to arrange a consultation.

• Face. One side of the face may droop, and it might be hard to smile.
• Arms. They may not be able to lift both arms and keep them there, because of weakness or numbness in one arm.
• Speech. They may slur their words or sound confused, or be unable to speak at all.
• Time. If you see any single one of these signs, it is time to call 999. Do not wait for the others, and do not wait to see whether it passes.