Lecture 8: The Heart as a Pump

Question 1

what are the phases of the cardiac cycle?

Answer 1

• Atrial Systole
• Isovolumetric Ventricular Contraction
• Ventricular ejection
• Isovolumetric ventricular relaxation
• Passive filling

Question 2

what is the difference between systemic and pulmonary arterial pressure?

Answer 2

systemic arterial pressure is high pressure
pulmonary arterial pressure is low pressure

• both circuits have periods of systole and diastole
• diastole is typically longer than systole

Question 3

what are the features of a blood pressure trace?

Answer 3

• systolic pressure is highest point on the trace
• diastolic pressure is lowest point on the trace
• pulse pressure is the difference between highest and lowest points
• mean pressure is the average across the full cycle (but will be closer to diastole)