Health Information

Acute Myocardial Infarction
Causes Acute Myocardial Infarction (AMI) is usually caused by atherosclerosis and thrombosis of coronary arteries. Heart is an important organ which pumps blood to various tissues in our body. Coronary arteries are blood vessels which supply blood, oxygen and nutrients for heart muscles to work. With time, particles like cholesterols and lipoproteins deposit on the wall of coronary arteries and form plaques. The process is known as atherosclerosis which continues and causes progressive narrowing of blood vessels. The plaque can sometimes rupture which attracts platelets and fibrin leading to thrombosis and blockages. Without blood supply, heart muscles cannot function and begin to die.   Symptoms and Diagnosis Typical symptoms of AMI include chest pain and discomfort, sometimes radiating to jaw and left arm. Other symptoms include sweating and shortness of breath. Atypical symptoms like indigestion and dizziness can also be due to AMI. Sometimes, cardiac arrest may be the first presentation of AMI.   Complications of AMI AMI causes heart muscles to die and fail to function which leads to cardiogenic shock and acute heart failure. Besides, the dying heart muscle can develop arrhythmia or heart structures may rupture which cause cardiac tamponade, acute mitral regurgitation or acute ventricular septal defect. All these conditions are immediate life-threatening and increase the chance of stroke or other organ failure. In long term, due to various degree of heart damage, survivors of AMI are at increased risk of chronic heart failure, arrhythmia and stroke etc.   Treatment Management of AMI mainly includes medications and other measures to restore the blood supply to the heart muscles. You may be given oxygen, intravenous fluids or medications and various monitoring devices to maintain vital parameters such as blood pressure, blood oxygenation and heart rate. Specifically for STEMI, the main aim of treatment is to open up the blocked coronary artery as soon as possible. It can be done by performing Primary Percutaneous Coronary Intervention (PPCI, known as Coronary Angioplasty) which opens up the blocked artery or using Thrombolytic Therapy which lyse the blood clot. You will also be given drugs such as anti-platelet agents or anti-thrombotics to make your blood thinner. Besides, other medications which help heart function or lower blood lipid may also be used. In some case, Coronary Artery Bypass Grafting Surgery (CABG, known as bypass surgery) may be needed.   (Source : Hospital Authority Smart Patient)
Learn More
What is Stroke? The medical term of stroke is "cerebral vascular disease". It occurs when blood supply to the brain is reduced or blocked for certain reasons leading to a sudden lack of oxygen in the brain cells. In a few minutes, the brain cells may be damaged and lose their functions. As a result, it affects the body functions controlled by that part of brain cells.   Stroke is a serious medical emergency. About 30% of the sufferers die in three months’ time. However, more than 50% of the survivors can fully resume self-care ability and less than 20% suffer from severe disability. The factors affecting recovery depend on the severity of brain damage (including the type of stroke and the area and site affected), the complications developed and the self-care ability of the patient before the stroke. Besides, the attitude of patients and the support from their families/carers as well as the appropriate rehabilitation treatments may also have decisive effects.   Stroke is mainly divided into two types: Ischemic stroke It is caused by cerebral thrombosis (a blood clot forms inside the vessels of the brain) and is relatively common, more than 70% of strokes belong to this type.  Also cerebral atherosclerosis causes formation of blood clot in the cerebral artery or the blood clots can be formed with the hearts or carotid artery in the neck. The clot can travel up to the cerebral vessels distally and block the flow of blood. Those cardiac diseases including arrhythmia (abnormal heart rate), cardiac valve problems and coronary heart disease could cause the stroke.   Hemorrhagic stroke It is caused by the bursting of a blood vessel inside the brain.  Most often, it is associated with persistent high blood pressure. There are also cases in which a blood vessel on the surface of the brain tissue bursts. This is associated with congenital cerebral vascular diseases. The blood would be released below the arachnoid space (the space between the brain tissue and the skull) pressing the brain tissue.  Moreover, the blood vessel will constrict after bleeding, further reducing the flow of blood. Both ischemia (inadequate flow of blood to a part of the body, caused by blockage of the blood vessels) and bleeding may prevent the brain tissue from receiving adequate nutrition and oxygen. The affected neurons will therefore die, giving rise to various neurologic symptoms. The causes of Transient ischemic attack (TIA) are similar to those of Ischemic stroke.   How to prevent Stroke? To prevent stroke, the most important aspect is to prevent the development of vascular atherosclerosis (blood vessel hardening). You may take following precautions to prevent stroke:   Controlling high blood pressure Lifestyle modification: Reducing sodium taken from diet, adhering to the "low-sodium, low-sugar, low-fat, high-fiber" dietary principle, controlling weight, taking exercise regularly and avoid addicted to alcohol Medication: taking medicine according to doctor's instructions Quit smoking immediately Controlling diabetes mellitus Lowering cholesterol: through diet and exercise, where necessary, taking medicine according to doctor's instructions Handling pressure and learning to relax       (Source: Hospital Authority Smart Patient)
Learn More
The Body Mass Index (BMI) is one of the methods for measuring overweight and obesity. It is calculated by dividing the body weight (in kg) by the square of height (in m): kg/m2. For Chinese adults living in Hong Kong, BMI from 23.0 to less than 25.0 kg/m2 is classified as overweight and BMI 25.0 kg/m2 or above is classified as obese.   Obesity increases the risk for chronic diseases, such as hypertension, heart diseases, hypercholesterolaemia, diabetes mellitus, cerebrovascular disease, gall bladder disease, osteoarthritis, sleep apnoea and some types of cancer (breast, prostate, colorectal and endometrial).   Prevention A balanced diet and regular physical activity are the proven ways to achieve and maintain an ideal body weight.   Balanced diet A balanced diet contributes to good health. It shall include a variety of foods providing appropriate calorie and nutrients. Members of the public are advised to follow the principles of the Healthy Eating Food Pyramid and include the five basic food groups (i.e. grains; fruit; vegetables, meat along with fish, eggs and legumes; milk and milk products) and be active in decreasing fat, salt and sugar intake.   Imbalanced or poor diet may lead to obesity or specific nutrient deficiency. These in turn may increase the risk of a variety of health problems, such as heart diseases, cerebrovascular disease, diabetes mellitus, hypertension and certain kind of cancers. Adequate amounts of fruit and vegetable intake is an essential component of healthy eating. WHO recommends a daily intake of at least 400 grams of fruit and vegetables (about 5 servings of fruit and vegetables) for the prevention of chronic diseases such as heart diseases, hypertension, cerebrovascular diseases, diabetes and certain cancers.   There is sufficient evidence in humans that consumption of processed meat causes colorectal cancer. Members of the public are urged to avoid processed meat and associated products.   Regular physical activity For adults aged 18 and above, including those living with chronic conditions or disability, the World Health Organization recommends that: They should do at least 150–300 minutes of moderate-intensity aerobic physical activity; or at least 75–150 minutes of vigorous-intensity aerobic physical activity; or an equivalent combination of moderate- and vigorous-intensity activity throughout the week, for substantial health benefits.   (Source: Department of Health)
Learn More