List in order, the mechanical phases of the cardiac cycle Please draw the pressure changes in the ventricle that occur during the cardiac cycle 1. Atrial systole 2. Ventricular isovolumetric contraction 3. Ventricular ejection 4. Ventricular isovolumetric relaxation 5. Ventricular filling 2009-1, 2005-1 Describe the pressure and volume changes at the onset of systole Describe the pressure and volume changes at the onset of diastole Relate the aortic pressure to the phases of the cardiac cycle 2005-1 When do the heart sounds occur? 2003-2 2007-2 Draw and label a diagram of the jugular venous pressure wave How does the ECG relate to the jugular venous pressure 2011-1, 2010-2, 2008-1, 2003-2 (+ contractility) What are the parameters that define cardiac output? CO = SV x HR What are the factors that influence stroke volume? Preload (= EDV or cardiac fiber length) Afterload Contractility What is cardiac preload? Amount of blood in ventricles at the end of diastole = end diastolic volume (Usually 130ml). Also the amount of stretch of cardiac muscles c.f. resting length. What factors affect preload? Blood volume Venous return e.g. increased by blood volume, venous constriction, muscle pump, negative intrathoracic pressure, venous compression (uterus in pregnancy)
List in order, the mechanical phases of the cardiac cycle Please draw the pressure changes in the ventricle that occur during the cardiac cycle 1. Atrial systole 2. Ventricular isovolumetric contraction 3. Ventricular ejection 4. Ventricular isovolumetric relaxation 5. Ventricular filling 2009-1, 2005-1 Describe the pressure and volume changes at the onset of systole Describe the pressure and volume changes at the onset of diastole Relate the aortic pressure to the phases of the cardiac cycle 2005-1 When do the heart sounds occur? 2003-2 2007-2 Draw and label a diagram of the jugular venous pressure wave How does the ECG relate to the jugular venous pressure 2011-1, 2010-2, 2008-1, 2003-2 (+ contractility) What are the parameters that define cardiac output? CO = SV x HR What are the factors that influence stroke volume? Preload (= EDV or cardiac fiber length) Afterload Contractility What is cardiac preload? Amount of blood in ventricles at the end of diastole = end diastolic volume (Usually 130ml). Also the amount of stretch of cardiac muscles c.f. resting length. What factors affect preload? Blood volume Venous return e.g. increased by blood volume, venous constriction, muscle pump, negative intrathoracic pressure, venous compression (uterus in pregnancy)