The cardiac cycle Flashcards
what are the two main phases of the cardiac cycle
diastole - when the heart ventricles are relaxed
systole - when the ventricles contract
what is the cardiac cycle
it is the sequence of events that occur when the heart beats
define one cardiac cycle
it is the contraction of the 2 atria followed by the contraction of the 2 ventricles
how are heart sounds generated
by the beating heart and the resultant flow of blood through it
what do the heart sounds reflect
the turbulence created when the heart valves snap shut
what is the second heart sound caused by
the close of aortic and pulmonic valves
what does the second heart sound mark
the end of systole
what defines systole
the time period elapsing between the first heart sound and second sound
what defines diastole
the time between the second sound and the following first sound
what is a phonocardiogram
a chart or record of the sounds made by the heart
what does the width of the pressure-volume loop represent
the difference between the end-diastolic and end-systolic volume, which is by definition the stroke volume
what is the area enclosed by the pressure-volume loop a measure of
the ventricular stroke work, which is a product of the stroke volume and the mean aortic and pulmonary artery pressure (after-load), depending on whether one is considering the left or the right ventricle
