Heart as a pump

Heart as a pump

Heart as a pumpExcitation-contraction

Heart as a pumpThe force-length relationship of myocardial fibers

Heart as a pumpThe force-length relationship of myocardial fibers

6

Heart as a pumpVentricular Pressure-Volume Relationship

End -diastolic ventricular

volume(ESV)

End -systolic ventricular

volume(EDV)

Stroke Volume(SV)

Ejection Fraction = SV/EDV

7

Heart as a pumpVentricular Pressure-Volume Relationship

Heart as a pump

Heart as a pump

Contraction of the atrial muscle narrows the orifices of the superior and inferior vena cava and pulmonary veins

Heart as a pump

Av valves• Mitral • Tricuspid

Semilunar valves• Aorta • Pulmonary

Cardiac valves and sounds

Heart as a pump

Heart sounds • S1

Low frequency Loudest and longest

• S2 High frequency Shorter duration Low intensity

• S3 In children with thin chest wall

and heart failure In early diastole

• S4 Atrial contraction Occasionally in healthy

individual

Cardiac valves and sounds