A heart attack occurs when the flow of blood to the heart is blocked, most often by a build-up of fat, cholesterol and other substances, which form a plaque in the arteries that feed the heart (coronary arteries). The interrupted blood flow can damage or destroy part of the heart muscle.
A heart attack, also called a myocardial infarction, can be fatal, but treatment has improved dramatically over the years.
Symptoms
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
- Fatigue
- Lightheadedness or sudden dizziness
When to see a doctor
Act immediately. Some people wait too long because they don’t recognize the important signs and symptoms. Take these steps:
- Call for emergency medical help.
- Take nitroglycerin, if prescribed to you by a doctor.
- Take aspirin, if recommended.
Causes
A heart attack occurs when one or more of your coronary arteries become blocked. Over time, a coronary artery can narrow from the buildup of various substances, including cholesterol (atherosclerosis). This condition, known as coronary artery disease, causes most heart attacks.
During a heart attack, one of these plaques can rupture and spill cholesterol and other substances into the bloodstream. A blood clot forms at the site of the rupture. If large enough, the clot can completely block the flow of blood through the coronary artery.
Another cause of a heart attack is a spasm of a coronary artery that shuts down blood flow to part of the heart muscle. Use of tobacco and of illicit drugs, such as cocaine, can cause a life-threatening spasm. A heart attack can also occur due to a tear in the heart artery (spontaneous coronary artery dissection).
Risk factors
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. 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. High blood pressure that occurs with obesity, smoking, high cholesterol or diabetes increases your risk even more.
- High blood cholesterol or triglyceride levels.
- Diabetes.
- Family history of heart attack.
- Lack of physical activity.
- Obesity.
- Stress.
- Illegal drug use.
- A history of preeclampsia.
- A history of an autoimmune condition, such as rheumatoid arthritis or lupus.
Complications
Heart attack complications are often related to the damage done to your heart during a heart attack. This damage can lead to the following conditions:
- Abnormal heart rhythms (arrhythmias).
- Heart failure.
- Heart rupture.
- Valve problems.
Tests and diagnosis
Ideally, your doctor should screen you during regular physical exams for risk factors that can lead to a heart attack.
Tests will help check if your signs and symptoms, such as chest pain, indicate a heart attack or another condition. These tests include:
- Electrocardiogram (ECG). This first test done to diagnose a heart attack records the electrical activity of your heart via electrodes attached to your skin. Impulses are recorded as waves displayed on a monitor or printed on paper. Because injured heart muscle doesn’t conduct electrical impulses normally, the ECG may show that a heart attack has occurred or is in progress.
- Blood tests. Certain heart enzymes slowly leak out into your blood if your heart has been damaged by a heart attack. Emergency room doctors will take samples of your blood to test for the presence of these enzymes.
Additional tests
If you’ve had a heart attack or one is occurring, doctors will take immediate steps to treat your condition. You may also undergo these additional tests:
- Chest X-ray.
- Echocardiogram.
- Coronary catheterization (angiogram).
- Exercise stress test.
- Cardiac computerized tomography (CT) or magnetic resonance imaging (MRI).
Treatments and drugs
Heart attack treatment at a hospital
With each passing minute after a heart attack, more heart tissue loses oxygen and deteriorates or dies. The main way to prevent heart damage is to restore blood flow quickly.
Medications
Medications given to treat a heart attack include:
- Aspirin.
- Thrombolytics.
- Antiplatelet agents.
- Other blood-thinning medications. You’ll likely be given other medications, such as heparin, to make your blood less “sticky” and less likely to form clots. Heparin is given intravenously or by an injection under your skin.
- Pain relievers.
- Nitroglycerin.
- Beta blockers.
- ACE inhibitors.
Surgical and other procedures
In addition to medications, you may undergo one of the following procedures to treat your heart attack:
- Coronary angioplasty and stenting.
- Coronary artery bypass surgery.
Lifestyle and home remedies
Your lifestyle affects your heart health. The following steps can help you not only prevent but also recover from a heart attack:
- Avoid smoke.
- Control your blood pressure and cholesterol levels.
- Get regular medical checkups.
- Exercise regularly.
- Maintain a healthy weight.
- Eat a heart-healthy diet.
- Manage diabetes.
- Control stress.
- If you drink alcohol, do so in moderation.
Prevention
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.
- 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. You know the drill: Maintain a healthy weight with a heart-healthy diet, don’t smoke, exercise regularly, manage stress and control conditions that can lead to heart attack, such as high blood pressure, high cholesterol and diabetes.