Causes and Risk Factors of Heart Attack

A heart attack, referred to as myocardial infarction (MI) in medical terms, is a permanent damage of the heart muscle. In other words, it is death of a heart muscle due to lack of blood supply.

Causes of Heart Attach and Risk Factors

The root cause of most heart attacks is a blood clot that blocks one of the coronary arteries, which are responsible for bring blood and oxygen to the heart. If blood flow is blocked, human heart is starved of oxygen and heart cells die. The blockage means that a hard substance called plaque (made up of cholesterol and other cells) builds up in the walls of your coronary arteries.

A heart attack can occur in two cases.

1. When blood platelets stick to tears in the plaque, to form a blood clot that blocks blood from flowing to the heart.


2. When the gradual build-up of plaque blocks one of your coronary arteries.

Coronary Heart Disease (CHD) – The medical condition may block the flow of oxygen-rich blood to a section of heart muscle. Most heart attacks occur as a result of coronary heart disease (CHD). As a result, a waxy substance called plaque builds within the coronary arteries, known as atherosclerosis. It is a gradual process that may rupture inside of an artery, only to form on plaque's surface. Gradually, cloth within the arteries becomes large enough, to completely block blood flow through a coronary artery. If the blockage isn't treated quickly, a portion of heart muscle begins to impair and heart tissues are replaced with scar tissue.

Coronary Artery Spasm – It is a less common cause of heart attack as compared to coronary heart disease. A severe spasm (tightening) of a coronary artery may cuts off blood flow through the artery, which only occurs in the coronary arteries that aren't affected by atherosclerosis. A spasm of artery occurs due to usage of drugs such as cocaine, emotional stress or pain, exposure to cold weather or cigarette smoking

The exact cause of heart attacks is not always apparent. Heart attacks may occur:

• After a sudden increase in physical activity,


• after severe emotional or physical stress,


• due to illness,


• while resting or asleep and


• When one is active outside in cold weather.

One who is having a heart attack feels pain in his/her chest first, which further spreads to the ears, arms, neck, jaw, wrists, back, abdomen and shoulders.