Cardiac Cycle Flashcards
1
Q
atrial systole
A
- the contraction of the right and left atria pushing blood into the ventricles
2
Q
atrial distole
A
- the period between atrial contractions when the atria are repolarizing
3
Q
Ventricular systole
A
- Contraction of the right and left ventricles pushing blood into the pulmonary arteries and aorta
4
Q
ventricular distaole
A
- the period between ventricular contractions when the ventricles are repolarizing
5
Q
Preload
A
- refers to the tension in the ventricular wall at the end of diatole. it reflects the venous filling pressure that fills the left ventricle during diatole
6
Q
afterload
A
-Refers to the forces that impede the flow of blood out of the heart, primarily the pressure in the peripheral vasculature, the compliance of the aorta, and the mass and viscosity of blood
7
Q
stroke volume
A
- Refers to the volume of blood ejected by each contraction of the left ventricle
- normal SV range from 60-80ml depending on age, sex, and activity
8
Q
Cardiac output CO
A
- the amount of blood pumped from the left or right ventricle per minute
- it is equal to the product of stroke volume and HR
- normal CO for an adult male at rest is 4.5-5.0 L/min with women producing slightly less.
- CO can increase up to 25 l/min during exercise
9
Q
Venous return
A
- the amount of blood that returns to the right atrium each minute. this is similar in volume to the CO.
- Because teh cardiovascular system is a closed loop, venous return must equal CO when averaged over time