A heart attack occurs when part of the heart muscle is damaged or has died because the supply of blood rich in oxygen is poor or has stopped. Most heart attacks are caused by blood clots in the heart’s blood vessels, coronary arteries. Risk factors include a family history of heart attacks or high blood pressure, being obese, suffering stress, having diabetes, smoking and alcohol abuse. An uncomfortable pressure, tight squeezing sensation or pain is felt in the chest and often spreads across the shoulders, neck or arms; feeling breathless and dizzy, sweaty and flushed are some common symptoms. Immediate emergency treatment reduces the likelihood of debilitating injury.