Heart and along the conduction system of the heart. The heart receives blood low in oxygen from the systemic circulation, which enters the right atrium from the superior and inferior venae cavae and passes to the right ventricle. From here it is pumped into the pulmonary circulation, through the lungs where it receives oxygen and gives off carbon dioxide. Oxygenated blood then returns to the left atrium, passes through the left ventricle and is pumped out through the aorta to the systemic circulation−where the oxygen is used and metabolized to carbon dioxide. The heart beats at a resting rate close to
Athletic heart syndrome signals the heart to pump more blood through the body to counteract the oxygen deficit building in the skeletal muscles. Enlargement of the heart is a natural physical adaptation of the body to deal with the high pressures and large amounts of blood that can affect the heart during these periods of time. Over time, the body will increase both the chamber size of the left ventricle, and the muscle mass and wall thickness of the heart. Cardiac output, the amount of blood that leaves the heart in a given time period (i.e. liters per minute), is proportional to both