Coronary artery disease blocks the delivery of blood to the heart muscles. When too much activities are done by the organism, the heart will pump more blood but have less oxygen delivered in the heart muscles. The heart muscles will then do anaerobic metabolism or metabolism without oxygen which produces lactic acid causes chest pain or angina. In worst case scenario, coronary artery disease will lead to myocardial infarction or heart attach when exposed in too much stressed causing sudden increased in heart activity.
The organism will limit its activity for its heart will not pump or work harder which could lead to heart attack and worst the organism may die.
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