Cardiac Cycle

Question 1

Atrial systole

Answer 1

Contraction of the R and L atria to push blood into ventricles

Question 2

Atrial diastole

Answer 2

Period between atrial systole when atria are repolarizing

Question 3

Ventricular systole

Answer 3

Contraction of the L and R ventricles pushing blood into the pulmonary arteries and the aorta

Question 4

Ventricular diastole

Answer 4

Period between ventricular contractions when the ventricles are repolarizing

Question 5

Preload

Answer 5

Tension in the ventricular wall at the end of diastole

Reflect venous filling pressure that fills the LV during diastole

Question 6

Afterload

Answer 6

Forces that impede flow of blood out of the heart

Ie peripheral resistance, aortic compliance, and mass/viscosity of blood

Question 7

Stroke volume (SV)

Answer 7

Volume of blood ejected by LV contraction

NORMAL RANGE: 60-80 mL

Question 8

Cardiac (CO)

Answer 8

Amount of blood pumped from the LV per minute
CO= HR x SV
NORMAL CO (at rest) 4.5 - 5.0 L/min
Can ↑ up to 25 L/min during exercise

Question 9

Venous return

Answer 9

Amount of blood that returns to RA each minute

venous return = CO