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The downward slope - Cardiac output

4 important questions on The downward slope - Cardiac output

How can the cardiac output be controlled?

1. Frank-Starlings law of the heart
2. Peripheral resistance

What factors cause hypereffectivity of the heart?

1. nervous stimulation- activation of the sympathetic and inhibition of the parasympathetic nervous system
2. hypertrophy of the heart muscle

How does sympathetic innervation affect cardiac output?

Increases- causes constriction of the peripheral vessels (veins), thereby increasing the mean systemic pressure. This, therefore, ultimately increases the cardiac output.

How does increase blood volume affect the cardiac output?

Increases- increased blood volume will increase the systemic filling pressure= increases atrial pressure= increases the venous return= increases the cardiac output.

Eventually, the cardiac output returns to normal:

1. blood volume returns to normal- increase in blood volume increases the capillary pressure- leads to fluid leaking out
2. increase in blood volume= distends the veins and decreases the resistance
3. autoregulation will cause the venous return to come back to normal