4: Cardiac cycle, valves, murmurs

• 2 parts of systole...

  Isovolumetric ventricular contraction: pressure is increasing

  • AV valves: closed
  • Aortic and pulmonary valves: closed

  Ventricular ejection:

  • AV valves: closed
  • Aortic and pulmonary valves: open
• 3 parts of diastole:

  Isovolumetric ventricular relaxation:

  • AV valves: closed
  • Aortic and pulmonary valves: closed

  Ventricular filling (start):

  • AV valves: open
  • Aortic and pulmonary valves: closed

  Ventricular filling (end) + atrial contraction:

  • AV valves: open
  • Aortic and pulmonary valves: closed
• When atrial pressure is greater than ventricular pressure, the AV valves are open.
• The aortic and pulmonary valves only open when ventricular pressure finally exceeds aortic and pulmonary pressure during ventricular ejection phase.