Overview

A heart attack occurs when the flow of blood to the heart is severely reduced or blocked. The blockage is usually due to a buildup of fat, cholesterol and other substances in the heart (coronary) arteries. The fatty, cholesterol-containing deposits are called plaques. The process of plaque buildup is called atherosclerosis.

Sometimes, a plaque can rupture and form a clot that blocks blood flow. A lack of blood flow can damage or destroy part of the heart muscle.

A heart attack is also called a myocardial infarction.

Prompt treatment is needed for a heart attack to prevent death. Call 911 or emergency medical help if you think you might be having a heart attack.

Symptoms

Symptoms of a heart attack vary. Some people have mild symptoms. Others have severe symptoms. Some people have no symptoms.

Common heart attack symptoms include:

• Chest pain that may feel like pressure, tightness, pain, squeezing or aching
• Pain or discomfort that spreads to the shoulder, arm, back, neck, jaw, teeth or sometimes the upper belly
• Cold sweat
• Fatigue
• Heartburn or indigestion
• Lightheadedness or sudden dizziness
• Nausea
• Shortness of breath

Women may have atypical symptoms such as brief or sharp pain felt in the neck, arm or back. Sometimes, the first symptom sign of a heart attack is sudden cardiac arrest.

Some heart attacks strike suddenly. But many people have warning signs and symptoms hours, days or weeks in advance. Chest pain or pressure (angina) that keeps happening and doesn’t go away with rest may be an early warning sign. Angina is caused by a temporary decrease in blood flow to the heart.

When to see a doctor

Get help right away if you think you’re having a heart attack. Take these steps:

• Call for emergency medical help. If you think you’re having a heart attack, immediately call 911 or your local emergency number. If you don’t have access to emergency medical services, have someone drive you to the nearest hospital. Drive yourself only if there are no other options.
• Take nitroglycerin, if prescribed to you by a health care provider. Take it as instructed while awaiting emergency help.
• Take aspirin, if recommended. Taking aspirin during a heart attack may reduce heart damage by preventing blood clotting.Aspirin can interact with other drugs. Don’t take an aspirin unless your care provider or emergency medical personnel say to do so. Don’t delay calling 911 to take an aspirin. Call for emergency help first.

What to do if you see someone who might be having a heart attack

If someone is unconscious and you think they’re having a heart attack, first call 911 or your local emergency number. Then check if the person is breathing and has a pulse. If the person isn’t breathing or you don’t find a pulse, only then should you begin CPR.

• If you’re untrained in CPR, do hands-only CPR. That means push hard and fast on the person’s chest — about 100 to 120 compressions a minute.
• If you’re trained in CPR and confident in your ability, start with 30 chest compressions before giving two rescue breaths.