1. Cardiac Physiology
Class 1

6. Cardiac Cycle
Class 2

7. Figure 20-17 Pressure and Volume Relationships in the Cardiac Cycle.
Step 1
ONE CARDIAC CYCLE
QRS complex
QRS complex
Electro- cardiogram (ECG) P T P
ATRIAL DIASTOLE
ATRIAL SYSTOLE
ATRIAL DIASTOLE
ATRIAL SYSTOLE
VENTRICULAR DIASTOLE
VENTRICULAR SYSTOLE
VENTRICULAR DIASTOLE
120 5 6
Aorta 90 1 2
Pressure (mm Hg) 60 3
Left ventricle 4 4 7 5 6 7 30
Left atrium 8 2 1 3 8
130
End-diastolic volume 3 2
Left ventricular volume (mL) 1
Stroke volume
End-systolic volume 6 50
100
200
300
400
500
600
700
800
Time (msec)

8. Cardiodynamics
Class 3

9. Figure 20-23 Factors Affecting Stroke Volume.
Step 1
Factors Affecting Stroke Volume (SV)
Venous return (VR)
Filling time (FT)
Increased by sympathetic stimulation
Decreased by parasympathetic stimulation
Increased by E, NE, glucagon, thyroid hormones
Contractility (Cont) of muscle cells
Preload
Increased by vasoconstriction
Decreased by vasodilation
Afterload (AL)
End-diastolic volume (EDV)
End-systolic volume (ESV)
STROKE VOLUME (SV)

10. Figure 20-24b A Summary of the Factors Affecting Cardiac Output.
Factors affecting heart rate (HR)
Factors affecting stroke volume (SV)
HEART RATE (HR)
STROKE VOLUME (SV) =
CARDIAC OUTPUT (CO) = b
Factors affecting cardiac output