Heart Attack Causes

Most heart attack causes are a result of coronary artery disease (CAD). CAD is the buildup over time of a material called plaque on the inner walls of the coronary arteries. Eventually, a section of plaque can break open, causing a blood clot to form at the site. A heart attack occurs if the clot becomes large enough to cut off most or all of the blood flow through the artery.

The blocked blood flow prevents oxygen-rich blood from reaching the part of the heart muscle fed by the artery. The lack of oxygen damages the heart muscle. If the blockage isn’t treated quickly, the damaged heart muscle begins to die.

Heart attack causes can be problems with the very small, microscopic blood vessels of the heart. This condition is called microvascular disease. It’s believed to be more common in women than in men.

Less common heart attack causes include a severe spasm (tightening) of a coronary artery that cuts off blood flow through the artery. These spasms can occur in coronary arteries that don’t have CAD. It’s not always clear what causes a coronary artery spasm, but sometimes it can be related to:

Taking certain drugs, such as cocaine
Emotional stress or pain
Exposure to extreme cold
Cigarette smoking

Heart Attack Causes and Risk

Certain risk factors make it more likely that you will develop coronary artery disease (CAD) and have a heart attack. Some risk factors for heart attack can be controlled, while others can´t.

Major risk factors for heart attack that you can control include:

Smoking
High blood pressure
High blood cholesterol
Overweight and obesity
Physical inactivity
Diabetes (high blood sugar)

Risk factors that you can´t change include:

Age. Risk increases for men older than 45 years and for women older than 55 years (or after menopause).
Family history of early CAD. Your risk increases if your father or a brother was diagnosed with CAD before 55 years of age, or if your mother or a sister was diagnosed with CAD before 65 years of age.

Certain CAD risk factors tend to occur together. When they do, it’s called metabolic syndrome. In general, a person with metabolic syndrome is twice as likely to develop heart disease and five times as likely to develop diabetes as someone without metabolic syndrome.