Already the Babylonians connected this Zodiac sign and the constellation with the mythological animal, sort of a mermaid goat. They called it the Goat-Fish. The reason for this is hidden in history.
Without an adequate blood supply, the heart muscle is deprived of oxygen and nutrients and waste products manufactured by the cells accumulates in the muscle tissue. Depending on the severity, it may cause myocardial ischemia, which is damage but not death of the muscle due to an inadequate blood supply. Alternatively it may cause death of the muscle tissue which is known as a myocardial infarction (MI).
This is called the Law of Mass Action. Very little oxygen actually gets through, but if you are consistently feeding your body the extra oxygen, there will be an extensive increase in your total tissue oxygen level. The goal is to keep the oxygen level of your blood as close as you can to 100 points.