Myocardial infarction

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Myocardial infarction ( Infarctus myocardii, MI) or acute myocardial infarction (AMI) is the medical term for an event commonly known as a heart attack. It happens when blood stops flowing properly to part of the heart and the heart muscle is injured due to not receiving enough oxygen. Usually this is because one of the coronary arteries that supplies blood to the heart develops a blockage due to an unstable buildup of white blood cells, cholesterol and fat. The event is called "acute" if it is sudden and serious.

A person having an acute myocardial infarction usually has sudden chest pain that is felt behind the breast bone and sometimes travels to the left arm or the left side of the neck. Additionally, the person may have shortness of breath, sweating, nausea, vomiting, abnormal heartbeats, and anxiety. Women experience fewer of these symptoms than men, but usually have shortness of breath, weakness, a feeling of indigestion, and fatigue. In many cases, in some estimates as high as 64 percent, the person does not have chest pain or other symptoms. These are called "silent" myocardial infarctions.

Important risk factors are previous cardiovascular disease, old age, tobacco smoking, high blood levels of certain lipids (low-density lipoprotein cholesterol, triglycerides) and low levels of high density lipoprotein (HDL) cholesterol, diabetes, high blood pressure, lack of physical activity, obesity, chronic kidney disease, excessive alcohol consumption, the use of cocaine and amphetamines, and chronic high stress levels. The two main ways to determine if a person has had a myocardial infarction are electrocardiograms (ECGs) that trace the electrical signals in the heart and testing the blood for substances associated with damage to the heart muscle. Common blood tests are creatine kinase (CK-MB) and troponin. ECG testing is used to differentiate between two types of myocardial infarctions based on the shape of the tracing. When the ST section of the tracing is higher than the baseline it is called an ST-elevation myocardial infarction (STEMI) which usually requires more aggressive treatment.

Immediate treatments for a suspected myocardial infarction include aspirin, which prevents further blood from clotting, and sometimes nitroglycerin to treat chest pain and oxygen.[6] STEMI is treated by restoring circulation to the heart, called reperfusion therapy, and typical methods are angioplasty, where the arteries are pushed open, and thrombolysis, where the blockage is removed using medications. Non-ST elevation myocardial infarction (NSTEMI) may be managed with medication, although angioplasty may be required if the person is considered to be at high risk.[8] People who have multiple blockages of their coronary arteries, particularly if they also have diabetes, may also be treated with bypass surgery (CABG) Ischemic heart disease, which includes myocardial infarction, angina and heart failure when it happens after myocardial infarction, was the leading cause of death for both men and women worldwide in 2011

Heart Attack

Heart Attack 

 A heart attack happens when the flow of oxygen-rich blood to a section of heart muscle suddenly becomes blocked and the heart can't get oxygen. If blood flow isn't restored quickly, the section of heart muscle begins to die. Heart attacks are a leading killer of both men and women in the United States. The good news is that excellent treatments are available for heart attacks. These treatments can save lives and prevent disabilities. Heart attack treatment works best when it's given right after symptoms occur. If you think you or someone else is having a heart attack (even if you're not fully sure), call 9–1–1 right away. Overview Heart attacks most often occur as a result of coronary heart disease (CHD), also called coronary artery disease. CHD is a condition in which a waxy substance called plaque (plak) builds up inside the coronary arteries. These arteries supply oxygen-rich blood to your heart. When plaque builds up in the arteries, the condition is called atherosclerosis (ath-er-o-scler-O-sis). The buildup of plaque occurs over many years. Eventually, an area of plaque can rupture (break open) inside of an artery. This causes a blood clot to form on the plaque's surface. If the clot becomes large enough, it can mostly or completely block blood flow through a coronary artery. If the blockage isn't treated quickly, the portion of heart muscle fed by the artery begins to die. Healthy heart tissue is replaced with scar tissue. This heart damage may not be obvious, or it may cause severe or long-lasting problems. Heart With Muscle Damage and a Blocked Artery Figure A shows a heart with dead heart muscle caused by a heart attack. Figure B is a cross-section of a coronary artery with plaque buildup and a blood clot. Figure A shows a heart with dead heart muscle caused by a heart attack. Figure B is a cross-section of a coronary artery with plaque buildup and a blood clot. A less common cause of heart attack is a severe spasm (tightening) of a coronary artery. The spasm cuts off blood flow through the artery. Spasms can occur in coronary arteries that aren't affected by atherosclerosis. Heart attacks can be associated with or lead to severe health problems, such as heart failure and life-threatening arrhythmias (ah-RITH-me-ahs). Heart failure is a condition in which the heart can't pump enough blood to meet the body's needs. Arrhythmias are irregular heartbeats. Ventricular fibrillation is a life-threatening arrhythmia that can cause death if not treated right away. Don't Wait--Get Help Quickly Acting fast at the first sign of heart attack symptoms can save your life and limit damage to your heart. Treatment works best when it's given right after symptoms occur. Many people aren't sure what's wrong when they are having symptoms of a heart attack. Some of the most common warning symptoms of a heart attack for both men and women are: Chest pain or discomfort. Most heart attacks involve discomfort in the center or left side of the chest. The discomfort usually lasts more than a few minutes or goes away and comes back. It can feel like pressure, squeezing, fullness, or pain. It also can feel like heartburn or indigestion. Upper body discomfort. You may feel pain or discomfort in one or both arms, the back, shoulders, neck, jaw, or upper part of the stomach (above the belly button). Shortness of breath. This may be your only symptom, or it may occur before or along with chest pain or discomfort. It can occur when you are resting or doing a little bit of physical activity. Other possible symptoms of a heart attack include: Breaking out in a cold sweat Feeling unusually tired for no reason, sometimes for days (especially if you are a woman) Nausea (feeling sick to the stomach) and vomiting Light-headedness or sudden dizziness Any sudden, new symptom or a change in the pattern of symptoms you already have (for example, if your symptoms become stronger or last longer than usual) Not all heart attacks begin with the sudden, crushing chest pain that often is shown on TV or in the movies, or other common symptoms such as chest discomfort. The symptoms of a heart attack can vary from person to person. Some people can have few symptoms and are surprised to learn they've had a heart attack. If you've already had a heart attack, your symptoms may not be the same for another one. Quick Action Can Save Your Life: Call 9–1–1 If you think you or someone else may be having heart attack symptoms or a heart attack, don't ignore it or feel embarrassed to call for help. Call 9–1–1 for emergency medical care. Acting fast can save your life. Do not drive to the hospital or let someone else drive you. Call an ambulance so that medical personnel can begin life-saving treatment on the way to the emergency room. Take a nitroglycerin pill if your doctor has prescribed this type of treatment. Outlook Each year, close to 1 million people in the United States have heart attacks, and many of them die. CHD, which often results in heart attacks, is the leading killer of both men and women in the United States. Many more people could survive or recover better from heart attacks if they got help faster. Of the people who die from heart attacks, about half die within an hour of the first symptoms and before they reach the hospital.