Summary of events in the left atrium, left ventricle, and aorta during the cardiac cycle Left atrial pressure Enddiastolic End- Phase of card ac cycle 2=Isovolumetric ventricular contraction
Summary of events in the left atrium, left ventricle, and aorta during the cardiac cycle
110 Aortic pressure Left atrial pressure End-diastolic ECG Heart sounds Diastole Systo Diastole 4 Phase of cardac cycle 1= Ventricular filling 2= Isovolumetric ventricular contraction 3 Ventricular ejection
Copynight o The McGraw-Hill Companies. Inc Permission required for reproduction or display 1= Ventricular filling 2=Isovolumetric ventricular contraction 3= Ventricular ejection 4= Isovolumetric ventricular relaxation 3 00 工 Pulmonary artery pressure Right ventricular pressure Ti Ime Pressure changes in the right heart during a contraction cycle
Pressure changes in the right heart during a contraction cycle
Role of atria and ventricles during each cardiac cycle ° Atria-primer pump Ventricles-major source of power
• Atria──primer pump • Ventricles──major source of power Role of atria and ventricles during each cardiac cycle
Heart Sounds 1st sound soft low-pitched lub associated with closure of the av valves Marks the onset of systole 2nd sound louder dup associated with closure of the pa and aortic valves Occurs at the onset of diastole
Heart Sounds • 1 st sound – soft low-pitched lub – associated with closure of the AV valves – Marks the onset of systole • 2 nd sound – louder dup – associated with closure of the PA and aortic valves – Occurs at the onset of diastole