In this Medical Monday series, we’re talking about how your doctor reaches a diagnosis of common conditions associated with coagulation. It may help if you first read the introduction and the post about atrial fibrillation, before reading about today’s topic of stroke. Altogether we’re covering
- DVT, Deep Vein Thrombosis
- Post-thrombotic syndrome
- PE, Pulmonary Embolism
- Pulmonary hypertension
- AF, Atrial Fibrillation
- Heart Valve conditions – aortic and mitral
- Heart attack
Stroke is the term doctors use when a part of the brain dies because it has insufficient blood supply. There are two main types of stroke: those caused by a blockage in a blood vessel in the brain, and those caused by bleeding in the brain. In the USA there are approximately 750,000 strokes each year and the majority are due to a blockage in the blood flow. This can be due to a clot in the vessel (a thrombosis) or an clot that has come from somewhere else (an embolus). For people with atrial fibrillation there is a risk of a stroke due to an embolus from the heart, this is why people with AF take anticoagulants.
Knowing the signs and symptoms of a stroke can be lifesaving. Classic stroke symptoms can be recalled with the acronym FAST. Each letter in the word stands for one of the things you should watch for:
●Face – Sudden weakness or droopiness of the face, or problems with vision
●Arm – Sudden weakness or numbness of one or both arms
●Speech – Difficulty speaking, slurred speech, or garbled speech
●Time – Time is very important in stroke treatment. The sooner treatment begins, the better the chances are for recovery.
Signs and symptoms of a stroke may be similar to other conditions; the only way to know for sure is to be seen as soon as possible by an experienced doctor or nurse.
It is also very important that you act quickly if these symptoms occur for a brief time and recover. For example you might lose vision in one eye for a few minutes, or you might be unable to use your arm for a few minutes. This is called a Transient Ischaemic Attack (TIA). Immediate action can prevent this progressing to a stroke.
Questions your doctor may ask
If you have symptoms suggestive of a stroke, it is a medical emergency and you should get to hospital as soon as possible (do not drive yourself) or call an ambulance. Sometimes the diagnosis is obvious to a doctor but there are other conditions that can cause similar symptoms. If you have a TIA you should see your doctor as soon as possible or go to the emergency department.
Your doctor will want to know about your risk factors; are you a smoker, do you have high blood pressure, is there a history of stroke in your family, do you have diabetes or heart disease, and do you have a high cholesterol?
What your doctor may find
If you have had a stroke your doctor will examine you to see what part of the brain is affected. You should have a full examination of your nervous system This will include checking your vision and eye movements and the activity of the muscles of your face, including movement of your tongue and throat, and your doctor will check your arm and leg movements. Your doctor will also check your reflexes in your arms and legs.
Your doctor will also try to find out why you had a stroke. You should have your blood pressure checked and your doctor will want to know if you have an irregular heart rate. Sometimes a stroke can be due to problems with the arteries in your neck, your doctor will listen to the blood flow in your carotid arteries on both sides of your neck.
If you have had a TIA your doctor may not find any abnormality, but this is still a very serious condition.
Tests you may have
Brain scan: If you have just had a stroke or a TIA you will have an urgent CT or MRI scan. In most hospitals a CT is done first as this is fast and readily available. If you have had a bleed, this will show up on the CT scan, but it can be harder to see a stroke due to a blood clot straight after it has happened.
Heart tests: You will have an ECG to check your heart rhythm and to see if there is any evidence of underlying heart disease. Also, if you have had an embolic stroke, you will have an echo cardiogram to see if there is a source of a clot in your heart.
Carotid artery test: If you have had a TIA or an embolic stroke your doctor will probably organise a carotid ultrasound scan. This will show if the carotid arteries are narrowed and if there is any evidence of a blood clot or an irregular vessel surface which could act as a site for a blood clot to form. .
What it could be
- Severe migraine – This can cause problems with vision and in some people even causes some weakness.
- Inner ear problems – These can cause disturbed balance but do not usually cause any other weakness or problems with vision.
- Seizures – Some types of epilepsy can cause altered speech and weakness.
- Low blood sugar – People with diabetes will know about hypos, when their blood sugar is too low. Sometimes this can cause confusion and odd behaviour and even some weakness.
- Altered calcium level or low sodium – These can occur with other medical conditions and may cause confusion.