Describe the Events That Make Up the Cardiac Cycle
47-4 as well as electrical activity as represented by the ECGWhen the heart muscle is relaxed at end. Four phases of the cardiac cycle. The Cardiac Cycle Pressures In The Heart Teachmephysiology In the diastole phase heart ventricles relax and the heart fills with blood. . Diastole represents ventricular filling and systole represents ventricular contractionejection. In resting humans the heart beats approximately once per second. The atria contract at the same time forcing blood through the atrioventricular valves into the ventricles. The period of contraction that the heart undergoes while it pumps blood into circulation is called systole. Mechanical events of the cardiac cycle 1Atrial systole. It is initiated by spontaneous generation of action potential in SA sinoatrial node. As the heart beats it circulates blood through pulmonary and systemic circuits of the body. The eight-tenths of a second that a ...