cardiac cycle

Question 1

what is the definition of the cardiac cycle

Answer 1

sequence of mechanical and electrical events that occur during one heartbeat. this allows for one way flow in the cardiovascular system

Question 2

what is the definition of diastole

Answer 2

the chambers fill up with blood relax

Question 3

what is the definition of systole

Answer 3

the heart contracts to eject blood into the pulmonary systemic circulations. the right left atria contract simultaneously (atrial systole) followed by ventricular systole

Question 4

what are the 5 stages of the cardiac cycle

Answer 4

atrial systole
isovolumetric contraction
ventricular ejection
isovolumetric relaxation
ventricular passing/filling

Question 5

what is atrial systole

Answer 5

this phase occurs when the atria contract, pushing blood into the ventricles
it marks the end of ventricular diastole (filling phase) and completes the filling of the ventricles
the atrial kick contributes to 20-30% of ventricular filling

Question 6

each cardiac cycle is around how long

Answer 6

0.8 seconds assuming heart rate is 75bpm

Question 7

what is the x and y axis of the wiggers diagram

Answer 7

x is time
y volume 50-130ml in ventricles or pressure changes 0-120mmhg

Question 8

explain the layout of the wiggers diagram

Answer 8

in the pressure segment, the top curve is aortic pressure second curve is ventricular third curve is atrial
in the volume segment the top curve is ventricular volume
second is ecg
third is for heart sounds