Cardiac arrest, also known as cardiopulmonary arrest or circulatory arrest,it is the cessation of functional circulation of the blood due to failure of the heart to contract effectively it functions as two pumps or one. As four pumps the (1)left and (2)right atrium pump blood into the left and right ventricles. Then the Left and Right ventricles pump blood into the (3)lungs and (4)body respectively. Looking at the heart as two pumps, the atriums (L and R) pump into the ventricles. As one pump, the heart circulates the blood in the body.