<prompt> Cardiac output is decreased byIncreased Hea rateDecreased Hea rateIncreased stroke volumeIncreased strength of contraction  <response>: The amount of blood pumped out of the hea per beat is the stroke volume, is about 70 mL.The output of the hea per unit of time is the cardiac output cardiac output stroke voumehea rate Therefore decrease in hea rate decrease cardiac outputIncrease in either of hea rate or stroke volume or both increase cardiac outputRef: Ganongs Review of Medical Physiology Twenty-Third Edition Page No:514 