Increasing TPR causes a decrease in both cardiac output and venous return Figure 314

(a) A counterclockwise rotation of the venous return curve occurs. Increased TPR results in decreased venous return as blood is retained on the arterial side.

(b) A downward shift of the cardiac output curve is caused by the increased aortic pressure (increased afterload) as the heart pumps against a higher pressure.

Cardiac output

Cardiac output

Cardiac Output Venous Return Curve

Mean systemic pressure

Right atrial pressure (mm Hg) or end-diastolic volume (L)

Mean systemic pressure

Figure 3-14. Effect of increased total peripheral resistance (TPR) on the cardiac and vascular function curves and on cardiac output.

(c) As a result of these simultaneous changes, a new equilibrium point is established at which both cardiac output and venous return are decreased, but right atrial pressure is unchanged.

(2) Decreasing TPR causes an increase in both cardiac output and venous return (not illustrated).

(a) A clockwise rotation of the venous return curve occurs. Decreased TPR results in increased venous return as more blood is allowed to flow back to the heart from the arterial side.

(b) Upward shift of the cardiac output curve is caused by the decreased aortic pressure (decreased afterload) as the heart pumps against a lower pressure.

(c) As a result of these simultaneous changes, a new equilibrium point is established at which both cardiac output and venous return are increased.

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Responses

  • ines
    What recetly change occure in TPR?
    2 years ago
  • Lucas
    When TPR increase, will cardiac output increase as well?
    1 year ago
  • DARRYL SINCLAIR
    How vascular smooth nuscle affects tpr?
    1 year ago
  • awate
    How does ateriolar tpr increase vr?
    2 months ago
  • Sanna
    What causes changes in tpr?
    4 days ago

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