Have you ever heard of cardiac ischemia? Ischemia is a heart problem caused by narrowed arteries. It is a condition when the arteries are narrowed or blocked and the flow of oxygen rich blood is restricted to reach the heart muscle. This is also known as coronary heart disease or coronary artery disease. Ischemia can lead to heart attack if it is too severe or lasts for longer time. In most cases heart attack can happen without prior warning. This is medically referred to as silent ischemia.
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