Watch Dr. Mehmet Oz and other renowned cardiologists as they talk about this major killer, known in the medical world as a "myocardial infarction." Step inside the human body in a way that lets you completely understand what a heart attack is all about, how and why they happen, what to do in the event of a heart attack, and how you can take steps to avoiding one.

Your Heart Needs Blood

Your heart started beating 6 weeks after you were conceived, and it will continue to beat about 100,000 times a day, resting only between beats, until the end of your life. Its only function is to circulate the blood that nourishes and sustains your every cell. It pumps the 6 qts of blood your body contains through your entire circulatory system—over 60,000 miles of arteries, veins, and capillaries, more than twice the distance around the equator of the Earth—and it does that three times a minute. Read more

Your Beating Heart

Your heart is a hollow, muscular organ whose walls are composed of a special kind of muscle tissue: cardiac muscle. This tissue isn't found anywhere else in the body. The cells that compose this tissue pulsate of their own accord, without any outside stimulation. In fact, a heart removed from a human body will continue to beat. Read more

Atherosclerosis & Cholesterol

The hard, fatty arterial deposits called plaques are composed mostly of cholesterol, a soft, waxy substance that occurs naturally in your body. Cholesterol is necessary for your body's health, because it helps to produce cell membranes and is also necessary for the production of vitamin D and various steroid hormones. Your liver produces about 75% of your body's cholesterol. The rest comes from some of the foods you eat, like meat, egg yolks, and shrimp. Read more

Angina & Coronary Heart Disease

Coronary heart disease (CHD), also known as coronary artery disease (CAD), is the leading cause of death in the US. CHD is a broad term that includes chest pain (angina), heart attacks, sudden cardiac death syndrome, abnormal heart rhythms (arrhythmias), and heart failure due to a weakened heart, all caused by clogged cardiac arteries. Smoking (or using other forms of tobacco), high blood pressure, high levels of cholesterol, lack of exercise, and diabetes can all accelerate atherosclerosis and lead to an earlier onset of CHD. Read more

Heart Attack Symptoms

Symptoms of a heart attack are often more severe and longer-lasting than those of angina. Heart attacks can occur at any time or place, when you're resting or when you're in motion. Heart attacks can strike without warning, but there may be signs and symptoms, like angina, in advance. Read more

What Is a Heart Attack?

Sometimes the surface of a plaque in a coronary artery ruptures. The rupture releases substances that make platelets stickier, encouraging clots to form on the surface of the plaque. The clot can block the flow of blood through the already-narrowed artery entirely. Without blood, heart muscle tissue starts to die in what's termed a myocardial infarction—a heart attack. Read more

Risk Factors & Diagnosis

Risk Factors for Heart Attack

The more risk factors a person has, the greater the chance that he or she will have a heart attack. Fortunately, most of the risk factors for heart attack are controllable:

• High blood cholesterol, particularly high LDL-cholesterol
• High blood pressure
• Overweight or obesity
• Smoking or using tobacco in any form
• Diabetes
• Lack of exercise
• Unmanaged response to stress

Read more

Treating Heart Attacks

Heart attacks are medical emergencies. Anyone who might be having a heart attack should get to a hospital emergency room as quickly as possible, because the sooner treatment begins, the better the chances of survival. Cardiopulmonary resuscitation (CPR) should only be given if the person having the heart attack has gone into cardiac arrest—that is, if their heart has stopped beating and they've become unconscious. The same holds true for using an automatic external defibrillator (AED) on the patient. Read more

Restoring Blood Flow

Immediately clearing the blockage from the artery improves the chances of survival for some patients.

Angioplasty and stent placement, in which the artery is widened from within and a metal coil is left in place to keep it open, may be performed. If angioplasty isn't available, doctors may administer thrombolytic or fibrinolytic ("clot-busting") drugs such as streptokinase, tenectoplase, reteplase, or alteplase intravenously. These drugs may be given up to 12 hours after the patient arrives at the hospital. However, because these drugs can cause bleeding, they aren't appropriate for every heart attack patient. Read more

Rehabilitation

Heart attack patients are encouraged to get out of their hospital bed and perform simple physical activities, like sitting in a chair and reading, as soon as possible. Patients can perform more activities with every passing day. If there are no complications, normal activities, like going to work, can be resumed within 6 weeks. Read more