CV - Cardiac Cycle Flashcards
1
Q
If the heart is relaxed how is it described
A
diastole
2
Q
isovolumetric contraction
A
early systole during which the ventricles contract with no corresponding volume change (isovolumetrically). This short-lasting portion of the cardiac cycle takes place while all heart valves are closed.
3
Q
Systole
A
Contraction of heart
4
Q
Average resting HR
A
~70 b/m
5
Q
Cardiac cycle - time
A
0.8sec
6
Q
Ventricular Systole =
A
0.3 sec
7
Q
Ventricular Diastole =
A
0.5 sec
8
Q
Atrial Systole =
A
0.1 sec
Only adds ~30% to vol of blood
9
Q
Atrial Diastole =
A
0.7 sec
10
Q
Cardiac output =
A
Heart Rate x Stroke Volume
11
Q
Cardiac Output can be altered by
A
Control of HR
Control of Stroke Volume
12
Q
Average cardiac output
A
~5 litres per min
13
Q
Blood is redistributed by
A
Vasodilation
Vasoconstriction
14
Q
Intrinsic factors
A
Local
15
Q
Extrinsic factors
A
ANS & hormones
