Cardiac Cycle

• Atriole Systole

  • Both atria are filled with blood and contract simultaneously.
  • The openings of the vena cava and pulmonary veins are closed due to the atria’s contraction.
  • The atrio-ventricular valves open as the atria contract and blood is ejected to the ventricles.
• Ventricular Systole

  • Ventricles contract simultaneously
  • Its contraction closes the bicuspid and tricuspid valves so that blood doesn’t flow back into the atria.
  • RV pumps deoxygenated blood via the pulmonary artery
  • LV pumps oxygenated blood via the aorta.
• General Diastole

  • Ventrical and Atria relax
  • Semi-lunar valves close, preventing back flow to the arteries.
  • Deoxygenated blood goes to the right atrium
  • Oxygenated blood goes to the left atrium.