An arrhythmia is an irregular heartbeat – the heart may beat too fast (tachycardia), too slowly (bradycardia), too early (premature contraction) or too irregularly (fibrillation). Arrhythmias are heart-rhythm problems – they occur when the electrical impulses to the heart that coordinate heartbeats are not working properly i.e. like a short circuit.
Most arrhythmias are harmless, but occasionally the heart may beat too rapidly or slowly for normal function, in which case it may pose a danger to life.
What Causes Arrhythmia?
Many types of heart disease cause arrhythmia. Coronary disease is a common trigger, but some younger individuals may also have arrhythmias due to congenital anomalies. Medications and alcohol may also predispose to or induce arrhythmias.
The commonest symptom of an arrhythmia is palpitations.
Your cardiologist can run tests to find out if you have an arrhythmia.
How are Arrhythmias Diagnosed?
Treatment of Arrhythmias
Your treatment will depend on the type, cause and severity of your arrhythmia.
This may range from a purely conservative treatment with lifestyle modification and maneuvers to manage your own heart rhythm, to the usage of medicines, to surgical procedures like implanting an implantable cardioverter-defibrillator (ICD) or a pacemaker or performing radio-frequency catheter ablation treatments of short-circuiting pathways in the heart.
Cardiac arrest, (also known as cardiopulmonary arrest or circulatory arrest) is the cessation of normal circulation of the blood due to failure of the heart to contract effectively.
This usually occurs in the context of a sudden heart attack, where the heart stops to beat, although in younger individuals it may also occur due to arrhythmias.
Breathing stops as well, and the resulting lack of oxygen to the brain causes loss of consciousness.
Brain injury is likely if cardiac arrest goes untreated for more than five minutes.
Cardiac arrest is a medical emergency that, in certain situations is potentially reversible if treated early. Cardiopulmonary resuscitation (CPR) has been shown to be of great value, followed by defibrillation. Immediate activation of the Civil Defence ambulance is absolutely necessary.
CPR training is available at many CPR training centers in Singapore.
At certain locations (e.g. airport, some shopping malls), there is an automated external defibrillator (AED) is available and the usage of an AED by a trained personnel may prove the difference between life and death for the cardiac arrest victim.
Similarly, most CPR training centers also offer AED user training as a subsequent course.
Act now and save lives!
Can sudden cardiac arrest be prevented?
Death is best treated by prevention. Most sudden death is associated with heart disease, so the at-risk population remains males older than 40 years of age who smoke, have high blood pressure, and diabetes (the risk factors for heart attack). Other risks include syncope (fainting or loss of consciousness) and known heart disease.
Syncope, or loss of consciousness, is a significant risk factor for sudden death. While some reasons for passing out are benign, there is always a concern that the reason was an abnormal heart rhythm that subsequently spontaneously corrected. The fear is that the next episode will be a sudden cardiac arrest. Depending on the healthcare provider’s suspicion based on the patient’s history, physical examination, laboratory tests, and EKG, the healthcare practitioner may recommend inpatient or outpatient heart monitoring to try to find a clue as to whether the passing out was due to a deadly heart rhythm. Unfortunately, the potentially suspect rhythm may not recur and depending on the situation, prolonged outpatient monitoring lasting weeks and months may be necessary. Use of electrophysiologic testing may help identify high risk patients (the electrical pathways are mapped using techniques similar to heart catheterization).
In people who present to their doctor with chest pain, aside from making the diagnosis, monitoring both the heart rate and rhythm are emphasized. The purpose of watching people with chest pain in a hospital setting is to prevent sudden cardiac arrest.
Using implantable defibrillators in high risk patients, especially those with markedly decreased ejection fractions can reduce the incidence of sudden cardiac arrest. These devices are placed under the skin in the chest wall and have wires that are attached to the heart itself. When they detect ventricular fibrillation, a shock is automatically delivered to the heart, restoring a heart beat and averting sudden death.
Cholesterol is a steroid metabolite found in the cell membranes and transported in the blood plasma of all animals. Small quantities are required for the normal functioning of the cells and the body.
However, most people due to the modern lifestyle and diet tend to have an excess of cholesterol which usually poses a problem.
Why is High Cholesterol a Problem?
High levels of LDL-C (“bad” cholesterol) are a risk factor for the formation of atheromas (basically cholesterol plaques). These atheromas form on the inner lining of the blood vessels in the heart and brain and result in heart disease and strokes.
On the other hand, HDL-C (“good” cholesterol) is able to remove LDL-C from the system, and has been shown to be protective against the formation of atheromas and hence heart disease and strokes.
As high levels of LDL-C are completely silent, it is hence important to perform annual health screenings to check the cholesterol levels.
Treatment of High Cholesterol
This is usually using a combination of lifestyle, dietary modifications as well as medications. Modern day cholesterol medications like statins are safe for usage and associated with very low risks of serious side effects.
A congenital heart defect (CHD) is a defect in the structure of the heart and great vessels which is present at birth. Many types of heart defects exist, most of which either obstruct blood flow in the heart or vessels near it, or cause blood to flow through the heart in an abnormal pattern.
Other defects, such as long QT syndrome, affect the heart’s rhythm. Heart defects are among the most common birth defects and are the leading cause of birth defect-related deaths.
Approximately 9 people in 1000 are born with a congenital heart defect. Many defects don’t need treatment, but some complex congenital heart defects require medication or surgery.
What are the Signs and Symptoms of CHD?
Many congenital heart defects have few or no symptoms. A doctor may not even detect signs of a heart defect during a physical exam.
Some heart defects do have symptoms. These depend on the number and type of defects and how severe the defects are. Severe defects can cause symptoms, usually in newborn babies.
These symptoms can include:
Congenital heart defects don’t cause chest pain or other painful symptoms.
Abnormal blood flow through the heart caused by a heart defect will make a certain sound. Your doctor can hear this sound, called a heart murmur, with a stethoscope. However, not all murmurs are a sign of a congenital heart defect. Many healthy children have heart murmurs.
Normal growth and development depend on a normal workload for the heart and normal flow of oxygen-rich blood to all parts of the body. Babies with congenital heart defects may have cyanosis or tire easily when feeding. Sometimes they have both problems. As a result, they may not gain weight or grow as they should.
Older children may get tired easily or short of breath during exercise or activity. Many types of congenital heart defects cause the heart to work harder than it should. In severe defects, this can lead to heart failure, a condition in which the heart can’t pump blood strongly throughout the body.
Symptoms of heart failure include:
Sometimes CHD improves without treatment. Other defects are so small that they do not require any treatment. Usually CHD is a serious affliction and requires surgery and/or medications.
Medications include diuretics, which aid the baby in eliminating water, salts, and digoxin for strengthening the contraction of the heart. This slows the heartbeat and removes some fluid from tissues. Some defects require surgical procedures to restore circulation back to normal and in some cases, multiple surgeries are needed. Interventional cardiology now offers patients minimally invasive alternatives to surgery. Device closures can now be performed with a standard transcatheter procedure using a closure device mounted on a balloon catheter.
Most patients require life-long specialized cardiac care, first with a pediatic cardiologist and later with and adult congential cardiologist. There are more than 1.8 million adults living with congenital heart defects.
How are Congenital Heart Defects Diagnosed?
Serious congenital heart defects are generally identified during pregnancy or soon after birth. Less severe defects aren’t diagnosed until children are older. Minor defects often have no symptoms and are diagnosed based on results from a physical exam and special tests done for another reason.
What is a Coronary Angiogram?
Coronary Angiogram is an X-ray study of your heart(coronary) vessels that involves the insertion of soft, tiny plastic tubes called a catheter, via the groin or wrist blood vessel. This procedure is carried out in the cardiac catheterisation laboratory.
The purpose of the study is to confirm the presence of CAD (Coronary Artery Disease) and to locate the exact site of blockage and its severity.
How is the Procedure Carried Out
Your doctor will administer local anaesthesia to numb the skin insertion site which may be on the groin or wrist.
A catheter is inserted through the blood vessel and advanced to the heart (coronary) blood vessel.
The catheter is then manipulated by the doctor to engage the opening of the heart artery.
Special “X-ray dye” called contrast is then injected through the catheter into the heart artery.
The contrast allows the doctor to visualise images of the heart arteries and/or heart chambers on the X-ray monitor.
Any “blockage” (stenosis) of the heart artery would reveal as a narrowing or “underfilling/nonfilling” of the blood vessel.
Important to note: Coronary angiogram is a largely pain-freeprocedure.
Preparations before the procedure
The night before:
Day of procedure:
During the procedure:
be placed there.
You may feel:
What Happens After That
Potential Risks (rare) with Coronary Angiograms
You Should Go A&E If:
* You should arrange for a relative or friend to fetch you home.
* You are discouraged from driving home yourself. * You are advised to keep your follow-up appointment with your doctor.
What is a Percutaneous Coronary Intervention (PCI)?
PCI is a procedure that unblocks narrowed coronary arteries without performing any surgery.
PCI may include one or more of the following treatments:
Balloon Catheter Angioplasty
During procedure, the doctor will insert a cardiac catheter with a small balloon around it into the coronary artery.
The doctor then places the balloon in the narrowed area of the artery and expands it with liquid. This pushes the plaque (blockage) to the sides of the artery where it remains. This technique reduces the narrowing in the artery and restores the size of a normal artery. The doctor removes the balloon catheter at the end of procedure.
The doctor places a small, hollow metal (mesh) tube called a ‘stent’ in the artery to keep it open following a balloon angioplasty. The stent prevents closing of the artery during and after the procedure. Drug-eluting stents are commonly used now. These stents are coated with medication that helps prevent narrowing of the artery.
Preparations before the procedure
The night before:
Day of procedure:
In the ward:
During the procedure
After the Procedure
You should go A & E if:
*Your should arrange for a relative or friend to fetch you home. You are discouraged from driving home yourself.
*You are advised to keep your follow-up appointment with your doctor.
What is Coronary Artery Disease (CAD)?
Coronary artery disease (CAD) is the end result of the accumulation of atheromatous plaques within the walls of the coronary arteries (blood vessels) that supply the myocardium (the muscle of the heart) with oxygen and nutrients. Coronary artery disease remains the leading cause of death in the developed world and is ranked second most common cause of mortality in Singapore. CAD is also the most common cause of sudden death in adults over 20 years of age.
While the symptoms and signs of coronary artery disease are noted in the advanced state of disease, most individuals with coronary artery disease show no evidence of disease for decades as the disease progresses before the first onset of symptoms, often in the form of a “sudden” heart attack, finally arises. After decades of progression, some of these atheromatous plaques may rupture and (along with the activation of the blood clotting system) start limiting blood flow to the heart muscle.
Management of Coronary Artery Disease
The management of coronary artery disease can be divided into (1) primary prevention of coronary artery disease. (2) secondary prevention(definitive treatment of established coronary artery disease).
What is primary prevention of Coronary Artery Disease?
Primary prevention is the process to reduce cardiovascular risk factors before coronary artery disease develops.
What is secondary prevention of Coronary Artery Disease?
Secondary prevention is the process to reduce future risk of CAD exacerbation after clinically significant coronary artery disease has already been diagnosed.
What are the common risk factors that contribute towards development of coronary artery disease?
How to control the coronary artery disease risk factors?
1) Cholesterol control
2) Dietary therapy
3) High blood pressure
AHA 2006 Diet and Lifestyle Goals for Cardiovascular Disease Risk Reduction
Definitive Treatment of Coronary Artery Disease
The definitive treatment of established coronary artery disease would include initially cardiac medications that will improve the blood flow to the muscles of the heart and also to stabilize the cholesterol plaques within the coronary arteries.
The recommendations for primary prevention (risk factors control) will apply as the back bone of the treatment. Then comes the use of cardiovascular medications and this will usually include the use of
The definitive treatment for coronary artery disease if it is shown to be severe and patient has symptomatic chest pain (angina) despite medications would be either to undergo a coronary artery bypass surgery or angioplasty / stent.
Prevention is better than Cure
One would have to understand that the treatment of coronary artery disease is a life long treatment and cannot be stopped as the process of coronary artery disease is a progressive disease life long and has to be managed therefore on a long term basis. However once treatment has been instituted and the patient has been stabilized the lifestyle modifications and the oral medications would in most instances be sufficient to prolong the life of the patient as well as to keep the patient symptom free from angina.
Although improved treatment for heart disease is saving more lives, about half of all deaths occur before there is time to start treatment. Thus treatment no matter how sophisticated it may become, it is not the ideal solution of reducing deaths from heart disease. Preventing heart attacks by reducing coronary risk factors undoubtly can save lives and therefore modifying your risk factors can be thought of as preventive maintenance.
What is a CT Coronary Angiogram?
CT Coronary Angiogram also known as multi-slice CT scan is a non-invasive heart imaging test that uses a special X-ray examination to identify the coronary arteries, and any fatty or calcium deposits, if present, that are built up at the walls of the coronary arteries. These plagues, if left untreated will result in heart muscle disease, which in turn will results in shortness of breath, chest pain or heart attack if there are severe blockages.
CT Calcium Scoring
CT calcium scoring is a screening test that precedes the CT Coronary Angiogram. It detects the amount of calcium deposits also known as plagues in your coronary arteries. Coronary arteries calcifications are a marker for coronary atherosclerosis. The higher the calcium score, the higher is the likelihood of obstructive coronary disease. Accurate evaluation of the severity of artery blockage in patients with a lot of calcified blockages is difficult. Therefore, CT coronary angiogram will not be carried out.
CT Coronary Angiogram
CT coronary angiogram is a diagnostic test that detects significant blockagesin the coronary arteries using a special x-ray machine. ECG leads will be placed on your chest to monitor your heart rate. A small plastic cannula will be inserted into your arm vein. Medication may be given via the plastic cannula to stabilise or slow down you heart rate for better imaging results. An iodine-containing contrast dye will be injected into the plastic cannula on your arm during the scan. It is normal to feel a warm sensation in your body when the dye is injected. Before the scan, the radiographer will teach you how to hold your breath. You will need to hold your breath for approximately 15 seconds for a few times. The scan will take approximately 10 minutes to complete.
Preparations before the procedure
After the procedure
You may resume normal activities after the scan.
For patients taking diabetic medications, your physician will advise you on when you can start to take your diabetic medictions.
Potential risks for CT Coronary Angiogram
Factors that are unsuitable for CT Coronary Angiogram
Your physician will discuss with you on these factors and other options that are available to you.
The 12-lead electrocardiogram (ECG) is a diagnostic tool that measures and records the electrical activity of the heart from 12 points of view. Interpretation of these details allows diagnosis of a wide range of heart conditions.
These conditions can vary from minor to life threatening.
It is a relatively inexpensive test that can be performed readily in a clinic setting, but however, it is not accurate as it only takes a snap-shot of the electrical activity of the heart at the particular point in time, and also at rest.
Nevertheless it is excellent as a basic screening tool. No prior preparation is needed to perform an ECG (e.g. no fasting), although hairy chested individuals may require some shaving of the chest hair occasionally to perform the test accurately.
The ECG is often combined with a treadmill exercise test, in which case it’s accuracy increases and it is known as a treadmill exercise stress test.
What is a Heart Attack?
A heart attack (also known as a myocardial infarction) is caused by a sudden worsening of the stenosis or complete occlusion of one or more coronary arteries.
This is usually caused by the rupturing of an underlying atheromatous plaque. The end result is cessation/severe restriction of blood circulation to the heart muscles, resulting in muscular death (irreversible) if not treated on time.
The classical symptom is the onset of acute sudden crushing central chest pains associated with breathlessness and cold sweats. The pain may radiate to the jaw or left armpit commonly, and the ability to walk or move around becomes limited by the pain.
Another presentation is a sudden collapse.
In either scenario, the afflicted should be brought to either an emergency unit (by ambulance) within the next 10 minutes ideally. For collapsed patients, the commencement of CPR and defibrillation is of great importance.
Diagnostic tests that can be done to evaluate an acute myocardial infarction are a basic 12-lead Electrocardiogram (ECG), a set of cardiac enzymes (blood test) including a rapid bed side test.
Prompt medical intervention is life saving. Patients usually receive an emergency Balloon Angioplasty with a Stent implantation, apart from medications. Occasionally, some patients may require an urgent Coronary Artery Bypass Grafting (CABG), or they may be given Thrombolytic Therapy(clot dissolving medication).
Please visit our website to check your Heart Attack Risk http://www.heartattackrisk.sg
Coronary Artery Disease: Are Women at Risk?
It is common misconception that women do not develop Coronary Artery Disease. Much like men, women are at risk for heart disease and heart attacks, although in terms of the likelihood, it is lower. Having said that, women in general are still more likely to die of heart disease than of breast cancer.
What are the Risk Factors for Women?
The risk factors are the same as for men, and include:
Unique Features of Heart Disease in Women
Women are more likely to present with atypical symptoms of heart disease, like:
When in doubt, it is advisable to see a cardiologist for an urgent/early review, depending on the nature and severity of symptoms.
For the asymptomatic, risk factor control, a healthy lifestyle, and an annual health screening must not be neglected.
Congestive Heart Failure (CHF) is generally defined as inability of the heart to supply sufficient blood flow to meet the body’s needs.
The commonest cause is as a result of a previous heart attack (whereby a substantial part of the heart muscle dies). Other causes include poorly controlled long standing hypertension, diseases of the heart valves, as well as less well defined causes like viral infections etc.
The common symptoms include:
CHF is considered an end-organ failure state. It has a mortality rate comparable to cancer, and treatment really lies in the:
Medications are the mainstay of treatment, and other lifestyle measures may be implemented under a cardiologist’s supervision.
On occasion, there may be a role for a biventricular pacemaker insertion, as well as cardiac surgery. In the terminal stage, for suitable candidates, a heart transplant remains the only solution for cure.
What is high blood pressure?
Your blood pressure is a reflection of the mechanical pressure of your blood on your arteries.
High blood pressure (also called hypertension) occurs when the pressure on your arteries is higher than normal, as defined by large scale population studies.
How is Blood Pressure measured?
Blood pressure is measured with a blood pressure cuff (either manual or automated) and recorded as two numbers, for example, 120/80 mm Hg (millimeters of mercury). Blood pressure measurements are usually taken at the upper arm over the brachial artery.
The top, larger number is called the systolic pressure. This measure the pressure generated when the heart contracts (pumps). It reflects the pressure of the blood against arterial walls.
The bottom, smaller number is called the diastolic pressure. This reflects the pressure in the arteries while the heart is filling and resting between heartbeats.
Recommended guidelines to define normal and high blood pressure are:
Normal blood pressure less than 120/80mmHg
High blood pressure 140/90mmHg or higher
High blood pressure usually causes no symptoms and high blood pressure often is labeled “the silent killer.” People who have high blood pressure typically don’t know it until their blood pressure is measured.
Therefore, it is important to check your blood pressure regularly, at least once in every 3 months.
High blood pressure is a major risk for strokes and heart disease. Therefore it is crucial that high blood pressure be monitored, treated and controlled.
Most people (>90%) have primary hypertension (i.e. not due to any other medical problems), which is in part related to the following factors:
Medications as well as a combination of lifestyle and dietary measures are usually required.
Obesity: A Risk Factor for Coronary Artery Disease?
An ideal person’s body mass index (BMI) should be less than 25. The BMI can be calculated based on the following formula:
BMI = Weight (kg) / Height2 (m2)
Once your BMI exceeds 25.0, you are considered overweight, and obesity sets in once the BMI exceeds 30.0.
With obesity, there are definite physiological and metabolic changes that occur, and obese individuals are more prone to developing the risk factors for coronary artery disease and stroke, and hence developing the heart attack or stroke.
Some of these changes include:
1. High blood pressure
2. High cholesterol
3. Fatty liver
4. Diabetes mellitus (type II)
Whilst a person’s bodyweight and bodyshape is genetically determined to a certain extent, it is nevertheless important to adopt a healthy lifestyle, with regular exercise, a healthy diet (without excessive simple sugars, calories, fats or salt), restriction on alcohol intake, abstinence from smoking and a regular health screening at least once a year.
Any amount of weight reduction for an obese individual, when done the proper way, has a beneficial effect on protecting the heart and the blood vessels, as it is associated with positive metabolic changes.
Remember, there are no shortcuts and no replacement for a healthy lifestyle program.
Faulty electrical signaling in the heart causes rhythm disorders. A pacemaker uses low-energy electrical pulses to overcome this faulty electrical signaling.
Typically, during an acute episode of rhythm disorder, a temporary pacemaker may be inserted to regulate the heart’s rhythm (typically in a high dependency or intensive care unit). A permanent pacemaker is typically implanted in the left chest muscle area, with wires that run to the heart via the large blood vessels.
The permanent pacemaker is battery operated, but the battery life-span with improving technology is well in excess of 10 years (which means a change is necessary after 10+ years).
Pacemakers monitor and correct the electrical rhythm of your heart. For patients who have had heart attacks or are prone to rhythm disorders either due to genetic conditions or old age, the pacemaker is usually implanted to correct a abnormally slow heart beat.
However, pacemakers are also combined with an automated implanted cardioverter-defibrillator technology nowadays, and this allows for restoration of abnormally fast heart beats (e.g. ventricular fibrillation) for susceptible individuals.
Lastly, pacemakers have also been used in selected cases of heart failure patient to improve and preserve the cardiac function.
The insertion of a permanent pacemaker is a day surgical, low-risk procedure and does not usually require hospitalization. This can only be done by an appropriately trained cardiologist.
A stroke, known medically as a cerebrovascular accident (CVA), is the rapidly developing loss of brain function(s) due to disturbance in the blood supply to the brain. This can be due to ischemia (lack of blood flow) caused by blockage (thrombosis, arterial embolism), or a hemorrhage (leakage of blood). As a result, the affected area of the brain is unable to function, leading to inability to move one or more limbs on one side of the body, inability to understand or formulate speech, or an inability to see one side of the visual field.
A stroke is a medical emergency and can cause permanent neurological damage, complications, and even death. It is the leading cause of adult disability in the United States and Europe and it is the number two cause of death worldwide. Risk factors for stroke include advanced age, hypertension (high blood pressure), previous stroke or transient ischemic attack (TIA), diabetes, high cholesterol, cigarette smoking and atrial fibrillation. High blood pressure is the most important modifiable risk factor of stroke.
A stroke is occasionally treated in a hospital with thrombolysis (also known as a “clot buster”). Post-stroke prevention may involve the administration of antiplatelet drugs such as aspirin and dipyridamole, control and reduction ofhypertension, the use of statins, and in selected patients with carotid endarterectomy, the use of anticoagulants. Treatment to recover any lost function is stroke rehabilitation, involving health professions such as speech and language therapy, physical therapy and occupational therapy.
Stroke symptoms usually come on suddenly, and should always be treated as a medical emergency. They include a sudden onset of any of the following:
Why do stroke symptoms start so suddenly?
The symptoms of stroke begin suddenly because they are caused by an abrupt interruption of blood flow to an area of the brain. When this happens it only takes a few seconds for that part of the brain to stop functioning.
What causes a stroke?
Blockage of an artery
The blockage of an artery in the brain by a clot (thrombosis) is the most common cause of a stroke. The part of the brain that is supplied by the clotted blood vessel is then deprived of blood and oxygen. As a result of the deprived blood and oxygen, the cells of that part of the brain die and the part of the body that it controls stops working. Typically, a cholesterol plaque in a small blood vessel within the brain that has gradually caused blood vessel narrowing ruptures and starts the process of forming a small blood clot.
Risk factors for narrowed blood vessels in the brain are the same as those that cause narrowing blood vessels in the heart and heart attack (myocardial infarction). These risk factors include:
Another type of stroke may occur when a blood clot or a piece of atherosclerotic plaque (cholesterol and calcium deposits on the wall of the inside of the heart or artery) breaks loose, travels through the bloodstream and lodges in an artery in the brain. When blood flow stops, brain cells do not receive the oxygen and glucose they require to function and a stroke occurs. This type of stroke is referred to as an embolic stroke. For example, a blood clot might originally form in the heart chamber as a result of an irregular heart rhythm, such as occurs in atrial fibrillation.
Usually, these clots remain attached to the inner lining of the heart, but occasionally they can break off, travel through the blood stream, form a plug (embolism) in a brain artery, and cause a stroke. An embolism can also originate in a large artery (for example, the carotid artery, a major artery in the neck that supplies blood to the brain) and then travel downstream to clog a small artery within the brain.
A cerebral hemorrhage occurs when a blood vessel in the brain ruptures and bleeds into the surrounding brain tissue. A cerebral hemorrhage (bleeding in the brain) causes stroke symptoms by depriving blood and oxygen to parts of the brain in a variety of ways. Blood flow is lost to some cells. As well, blood is very irritating and can cause swelling of brain tissue (cerebral edema). Edema and the accumulation of blood from a cerebral hemorrhage increases pressure within the skull and causes further damage by squeezing the brain against the bony skull further decreasing blood flow to brain tissue and cells.
In a subarachnoid hemorrhage, blood accumulates in the space beneath the arachnoid membrane that lines the brain. The blood originates from an abnormal blood vessel that leaks or ruptures. Often this is from an aneurysm (an abnormal ballooning out of the wall of the vessel). Subarachnoid hemorrhages usually cause a sudden, severe headache, nausea, vomiting, light intolerance, and a stiff neck. If not recognized and treated, major neurological consequences, such as coma, and brain death may occur.
Another rare cause of stroke is vasculitis, a condition in which the blood vessels become inflamed causing decreased blood flow to brain tissue.
There appears to be a very slight increased occurrence of stroke in people with migraine headache. The mechanism for migraine or vascular headaches includes narrowing of the brain blood vessels. Some migraine headache episodes can even mimic stroke with loss of function of one side of the body or vision or speech problems. Usually, the symptoms resolve as the headache resolves.
Causes and Risk Factors of Stroke
There are two broad categories of strokes, called ischemic stroke or hemorrhagic stroke.
Ischemic stroke is caused by a blockage of a blood vessel in the brain or neck. This stroke can stem from three different conditions: thrombosis, embolism or stenosis:
Hemorrhagic stroke is the bleeding into the brain or the spaces surrounding the brain which is caused by a number of disorders that affect the blood vessels (i.e., high blood pressure and cerebral aneurysm). There are two types of hemorrhagic stroke: subarachnoid and intracerebral.
Some factors that increase the risk of stroke are genetically determined, others are simply a function of natural processes, and still others result from a person’s lifestyle. The factors resulting from heredity or natural processes can’t be changed, but those that are environmental can be modified with a doctor’s help.
There are five uncontrollable risk factors:
There are two basic controllable risk factors:
What is the treatment of a stroke?
Tissue plasminogen activator (TPA)
There is opportunity to use alteplase (TPA) as a clot-buster drug to dissolve the blood clot that is causing the stroke. There is a narrow window of opportunity to use this drug. The earlier that it is given, the better the result and the less potential for the complication of bleeding into the brain.
TPA must be given within 4 1/2 hours after the onset of symptoms. for patients who waken from sleep with symptoms of stroke, the clock starts when they were last seen in a normal state.
TPA is injected into a vein in the arm but, the time frame for its use may be extended to six hours if it is dripped directly into the blood vessel that is blocked requiring angiography, which is performed by an interventional radiologist. Not all hospitals have access to this technology.
TPA may reverse stroke symptoms in more than one-third of patients, but may also cause bleeding in 6% patients, potentially making the stroke worse.
For posterior circulation strokes that involve the vertebrobasilar system, the time frame for treatment with TPA may be extended even further to 18 hours.
Heparin and aspirin
Drugs to thin the blood (anticoagulation; for example, heparin) are also sometimes used in treating stroke patients in the hopes of improving the patient’s recovery. It is unclear, however, whether the use of anticoagulation improves the outcome from the current stroke or simply helps to prevent subsequent strokes (see below). In certain patients, aspirin given after the onset of a stroke does have a small, but measurable effect on recovery. The treating doctor will determine the medications to be used based upon a patient’s specific needs.
Managing other Medical Problems
Blood pressure will be tightly controlled often using intravenous medication to prevent stroke symptoms from progressing. This is true whether the stroke is ischemic or hemorrhagic. Supplemental oxygen is often provided.
In patients with diabetes, the blood sugar (glucose) level is often elevated after a stroke.
Controlling the glucose level in these patients may minimize the size of a stroke.
Patients who have suffered a transient ischemic attacks, the patient may be discharged with blood pressure and cholesterol medications even if the blood pressure and cholesterol levels are within acceptable levels. Smoking cessation is mandatory.
When a patient is no longer acutely ill after a stroke, the health care staff focuses on maximizing the individuals functional abilities. This is most often done in an inpatient rehabilitation hospital or in a special area of a general hospital. Rehabilitation can also take place at a nursing facility.
The rehabilitation process can include some or all of the following:
1. speech therapy to relearn talking and swallowing;
2. occupational therapy to regain as much function dexterity in the arms and hands as possible;
3. physical therapy to improve strength and walking; and
4. family education to orient them in caring for their loved one at home and the challenges they will face.
The goal is for the patient to resume as many, if not all, of their pre-stroke activities and functions. Since a stroke involves the permanent loss of brain cells, a total return to the patient’s pre-stroke status is not necessarily a realistic goal in many cases. However, many stroke patients can return to vibrant independent lives.
Depending upon the severity of the stroke, some patients are transferred from the acute care hospital setting to a skilled nursing facility to be monitored and continue physical and occupational therapy.
Many times, home health providers can assess the home living situation and make recommendations to ease the transition home. Unfortunately, some stroke patients have such significant nursing needs that they cannot be met by relatives and friends and long-term nursing home care may be required.
Prevention of Stroke
Strokes may be prevented by lowering your blood pressure, quitting smoking, beginning or increasing exercise, controlling medical problems with medications (i.e., atrial fibrillation requires anticoagulants), maintaining optimal weight, and eating a diet high in fruits and vegetables.
If you have a blocked carotid artery your doctor may suggest a carotid endarterectomy to remove the fatty deposits.