PT. Indosehat Lestari
The Heart
Your heart is the size of your fist and the strongest muscle in your body.
Your heart started beating about three weeks after you were conceived. If you live to be 70 your heart will have beat two and a half billion times. Each heartbeat pumps blood around the body, pushing it from the left heart chambers, through arteries of ever-decreasing size, finally reaching the capillaries in all parts of the body.
Once your body has taken oxygen and nutrients from the blood, it is returned to the heart via the veins to the right chambers of the heart. On its way back, the blood passes through the liver and waste products are removed.
As marvelous as this system is, it is very vulnerable to damage from the things we do to it, like smoking, eating an unhealthy diet or putting it under stress. Or you may be born with a heart condition. When your heart’s functions become compromised, this is known as cardiovascular disease, a broad term that covers any disorder to the system that has the heart at its centre.
Heart Attack
A heart attack occurs when the blood flow that brings oxygen to the heart muscle is severely reduced or cut off completely. This happens because coronary arteries that supply the heart muscle with blood flow can slowly become narrow from a buildup of fat, cholesterol and other substances that together are called plaque. This slow process is known as atherosclerosis . When a plaque in a heart artery breaks, a blood clot forms around the plaque. This blood clot can block the blood flow through the heart muscle. When the heart muscle is starved for oxygen and nutrients, it is called ischemia. When damage or death of part of the heart muscle occurs as a result of ischemia, it is called a heart attack or myocardial infarction (MI). About every 43 seconds, someone in the United States has a myocardial infarction (heart attack).
An estimated 17.3 million people die of cardiovascular diseases every year. 80% of the deaths occur in low- and middle-income countries.
Signs of Heart Attack
Some heart attacks are sudden and intense, but heart attacks start slowly, with mild pain or discomfort. Often people affected aren't sure what's wrong and wait too long before getting help. Here are signs that can mean a heart attack is happening:
• Chest discomfort. Most heart attacks involve discomfort in the center of the chest that lasts more than a few minutes, or that goes away and comes back. It can feel like uncomfortable pressure, squeezing, fullness or pain.
• Discomfort in other areas of the upper body. Symptoms can include pain or discomfort in one or both arms, the back, neck, jaw or stomach.
• Shortness of breath with or without chest discomfort.
• Other signs may include breaking out in a cold sweat, nausea or lightheadedness.
Heart Attack and Cardiac Arrest
• Heart attacks are caused by a blockage that stops blood flow to the heart.
• Cardiac arrest is caused when the heart's electrical system malfunctions. In cardiac arrest (also called sudden cardiac death or SCD), death results when the heart suddenly stops working properly.
• This is caused by abnormal, or irregular, heart rhythms (called arrhythmias). The most common arrhythmia in cardiac arrest is ventricular fibrillation. This is when the heart's lower chambers suddenly start beating chaotically and don't pump blood.
• Death occurs within minutes after the heart stops. Cardiac arrest may be reversed if CPR (cardiopulmonary resuscitation) is performed and a defibrillator is used to shock the heart and restore a normal heart rhythm within a few minutes.
Heart Attack Risk Factor
• Age. Men age 45 or older and women age 55 or older are more likely to have a heart attack than are younger men and women.
• Tobacco. Smoking and long-term exposure to secondhand smoke increase the risk of a heart attack.
• High blood pressure. Over time, high blood pressure can damage arteries that feed your heart by accelerating atherosclerosis.
• Diabetes. Having diabetes — not producing enough insulin or not responding to insulin properly — causes your body's blood sugar levels to rise. Diabetes, especially uncontrolled, increases your risk of a heart attack.
• Family history of heart attack. If your siblings, parents or grandparents have had early heart attacks (by age 55 for male relatives and by age 65 for female relatives), you may be at increased risk.
• Lack of physical activity. An inactive lifestyle contributes to high blood cholesterol levels and obesity. People who get regular aerobic exercise have better cardiovascular fitness, which decreases their overall risk of heart attack. Exercise is also beneficial in lowering high blood pressure.
• Obesity. Obesity is associated with high blood cholesterol levels, high triglyceride levels, high blood pressure and diabetes. Losing just 10 percent of your body weight can lower this risk, however.
• Stress. You may respond to stress in ways that can increase your risk of a heart attack.
• Illegal drug use. Using stimulant drugs, such as cocaine or amphetamines, can trigger a spasm of your coronary arteries that can cause a heart attack.
• A history of preeclampsia. This condition causes high blood pressure during pregnancy and increases the lifetime risk of heart disease.
• A history of an autoimmune condition, such as rheumatoid arthritis or lupus. Conditions such as rheumatoid arthritis, lupus and other autoimmune conditions can increase your risk of having a heart attack.