A heart attack occurs when the flow of blood to the heart is blocked. The blockage is most often a buildup of fat, cholesterol and other substances, which form a plaque in the arteries that feed the heart (coronary arteries). The plaque eventually breaks away and forms a clot. The interrupted blood flow can damage or destroy part of the heart muscle.
Common heart attack signs and symptoms include:
- Pressure, tightness, pain, or a squeezing or aching sensation in your chest or arms that may spread to your neck, jaw or back
- Nausea, indigestion, heartburn or abdominal pain
- Shortness of breath
- Cold sweat
- Lightheadedness or sudden dizziness
Some people have mild pain; others have more severe pain. Some people have no symptoms; for others, the first sign may be sudden cardiac arrest. However, the more signs and symptoms you have, the greater the likelihood you’re having a heart attack.Some heart attacks strike suddenly, but many people have warning signs and symptoms hours, days or weeks in advance. The earliest warning might be recurrent chest pain or pressure (angina) that’s triggered by exertion and relieved by rest. Angina is caused by a temporary decrease in blood flow to the heart.
Heart attack risk factors include:
- 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. This includes smoking and long-term exposure to secondhand smoke.
- High blood pressure. Over time, high blood pressure can damage arteries that feed your heart. High blood pressure that occurs with other conditions, such as obesity, high cholesterol or diabetes, increases your risk even more.
- High blood cholesterol or triglyceride levels. A high level of low-density lipoprotein (LDL) cholesterol (the “bad” cholesterol) is most likely to narrow arteries. A high level of triglycerides, a type of blood fat related to your diet, also ups your risk of heart attack. However, a high level of high-density lipoprotein (HDL) cholesterol (the “good” cholesterol) lowers your risk of heart attack.
- 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.
- Diabetes. Not producing enough of a hormone secreted by your pancreas (insulin) or not responding to insulin properly causes your body’s blood sugar levels to rise, increasing your risk of heart attack.
- Metabolic syndrome. This occurs when you have obesity, high blood pressure and high blood sugar. Having metabolic syndrome makes you twice as likely to develop heart disease than if you don’t have it.
- 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 might be at increased risk.
- Lack of physical activity. Being inactive contributes to high blood cholesterol levels and obesity. People who exercise regularly have better cardiovascular fitness, including lower high blood pressure.
- Stress. You might respond to stress in ways that can increase your risk of a heart attack.
- Illicit 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.
- An autoimmune condition. Having a condition such as rheumatoid arthritis or lupus can increase your risk of heart attack.
Complications are often related to the damage done to your heart during an attack, which can lead to:
- Abnormal heart rhythms (arrhythmias). Electrical “short circuits” can develop, resulting in abnormal heart rhythms, some of which can be serious, even fatal.
- Heart failure. An attack might damage so much heart tissue that the remaining heart muscle can’t pump enough blood out of your heart. Heart failure can be temporary, or it can be a chronic condition resulting from extensive and permanent damage to your heart.
- Sudden cardiac arrest. Without warning, your heart stops due to an electrical disturbance that causes an arrhythmia. Heart attacks increase the risk of sudden cardiac arrest, which can be fatal without immediate treatment.
Each minute after a heart attack, more heart tissue deteriorates or dies. Restoring blood flow quickly helps prevent heart damage.
- Aspirin and other anti-platelet agents help prevent new clots and keep existing clots from getting larger thus helping maintain blood flow through a narrowed artery.
- Thrombolytics also called clotbusters, help dissolve a blood clot that’s blocking blood flow to your heart.
- Nitroglycerin. This medication, used to treat chest pain (angina), can help improve blood flow to the heart by widening (dilating) the blood vessels.
- Beta blockers. These medications help relax your heart muscle, slow your heartbeat and decrease blood pressure, making your heart’s job easier. Beta blockers can limit the amount of heart muscle damage and prevent future heart attacks.
- ACE inhibitors. These drugs lower blood pressure and reduce stress on the heart.
- Statins. These drugs help control your blood cholesterol.
- Surgical Options:
- Coronary angioplasty and stenting.
In this procedure, also known as percutaneous coronary intervention (PCI), doctors insert a long, thin tube (catheter) that’s passed through an artery in your groin or wrist to a blocked artery in your heart. If you’ve had a heart attack, this procedure is often done immediately after a cardiac catheterization, a procedure used to find blockages. This catheter has a special balloon that, once in position, is briefly inflated to open a blocked coronary artery. A metal mesh stent might then be inserted into the artery to keep it open long term, restoring blood flow to the heart. Depending on your condition, you might get a stent coated with a slow-releasing medication to help keep your artery open.
- Coronary artery bypass surgery. In some cases, doctors perform emergency bypass surgery at the time of a heart attack. If possible, however, you might have bypass surgery after your heart has had time — about three to seven days to recover from your heart attack. Bypass surgery involves sewing veins or arteries in place beyond a blocked or narrowed coronary artery, allowing blood flow to the heart to bypass the narrowed section. Once blood flow to your heart is restored and your condition is stable, you’re likely to remain in the hospital for several days.