The fatty streaks in arteries continue to develop and bulge into arteries. This cholesterol “bulge” is then covered by a scar that produces a hard coat or shell over cholesterol and cell mixture. It is this collection of cholesterol that is then covered by a scar that is called “plaque.”

The buildup of plaque narrows space in arteries through which blood can flow, decreasing supply of oxygen and nutrients. This cuts down supply of blood and oxygen to tissues that are fed by that blood vessel.

The elasticity of blood vessel is reduced and arteries’ ability to control blood pressure is compromised. If there is not enough oxygen carrying blood passing through narrowed arteries, heart may give you a pain that is called angina.

The pain usually happens when you exercise because at that time your heart requires more oxygen. Usually it is felt in chest or left arm and shoulder, although it can happen without any symptoms at all.

Plaque can vary in size as well as shape. All through coronary arteries you can find many small plaques that cover less than half of an artery opening. Some of these plaques are completely invisible in tests that doctors use to identify heart disease.

The medical community used to think that primary concern was larger plaques. They thought these posed a greater threat because of their size and that they were more likely to cause a complete blockage of coronary arteries.

While it is true that larger plaques are more likely to cause angina, it is smaller plaques that are packed with cholesterol and covered by scars that are more dangerous. They are considered unstable and prone to ruptures or bursting releasing their load of cholesterol into bloodstream. This causes immediate clotting within artery. If blood clot blocks artery totally, it will stop blood flow and a heart attack occurs. The muscle o­n farter side of occurring clot fails to get oxygen it needs and begins to die. This kind of damage can be permanent.