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). A lack of blood to the heart may seriously damage the heart muscle and can be life threatening.
Not all people who have heart attacks have the same symptoms or have the same severity of symptoms. 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 chance you're having a heart attack.
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
A heart attack occurs when one or more of your coronary arteries becomes blocked. Over time, a buildup of fatty deposits, including cholesterol, form substances called plaques, which can narrow the arteries (atherosclerosis). This condition, called coronary artery disease, causes most heart attacks.
During a heart attack, a plaque can rupture and spill cholesterol and other substances into the bloodstream. A blood clot forms at the site of the rupture. If the clot is large, it can block blood flow through the coronary artery, starving the heart of oxygen and nutrients (ischemia).
You might have a complete or partial blockage of the coronary artery.
- A complete blockage means you've had an ST elevation myocardial infarction (STEMI).
- A partial blockage means you've had a non-ST elevation myocardial infarction (NSTEMI).
Diagnosis and treatment might be different depending on which type you've had.
Another cause of a heart attack is a spasm of a coronary artery that shuts down blood flow to part of the heart muscle. Using tobacco and illicit drugs, such as cocaine, can cause a life-threatening spasm.
Infection with COVID-19 also may damage your heart in ways that result in a heart attack.
Certain factors contribute to the unwanted buildup of fatty deposits (atherosclerosis) that narrows arteries throughout your body. You can improve or eliminate many of these risk factors to reduce your chances of having a first or another heart attack.
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.
- High blood cholesterol or triglyceride levels.
- Metabolic syndrome. This syndrome 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 attacks. If your siblings, parents or grandparents have had early heart attacks (by age 55 for males and by age 65 for females), you might be at increased risk.
- Lack of physical activity.
- 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 a heart attack.
Complications are often related to the damage done to your heart during a heart attack, which can lead to:
- Abnormal heart rhythms (arrhythmias).
- Heart failure.
- Sudden cardiac arrest.
It's never too late to take steps to prevent a heart attack — even if you've already had one. Here are ways to prevent a heart attack.
- Medications. Taking medications can reduce your risk of a subsequent heart attack and help your damaged heart function better. Continue to take what your doctor prescribes, and ask your doctor how often you need to be monitored.
- Lifestyle factors:
- Limiting your intake of ready-made snacks which are often high in sugar, fat and salt.
- Ensuring the intake of at least five servings of fresh fruits and vegetables a day.
- Reducing salt consumption to one teaspoon a day.
- Preparing meals at home for school or work.
- Quitting smoking.
- Increasing activity by limiting the time spent watching TV or using the computer, and getting involved in outdoor activities such as cycling, gardening, or simply walking.
- Knowing your risk of CVD by consulting a healthcare professional who can measure your blood pressure, cholesterol and glucose levels, weight and body mass index, and can also advise on a treatment plan if needed.
- Incorporating exercise at work by using the stairs, standing up to answer phone calls and having regular breaks to stretch or exercise for five minutes.
- Encouraging children to be active and getting active yourself by participating in a sport or exercise routine or simply by helping out in household chores.
- A heart attack is a medical emergency. Call 999 and ask for an ambulance if you think you might be having a heart attack.