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The primary parameters of heart pumping are

  1. strength of contractility (inotropic positive; Frank-Starling relationship)
  2. rate of relaxation (lusitropic positive)
  3. heart rate (chronotropic positive)

which change the secondary parameters according to the marginals

  1. Heart rate
  2. Stroke volume
    • Contractility
    • Starling relationship

Which of these paramecers are controlled intracardiacally and which extracardiacally?

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up vote 2 down vote accepted

Rate is controlled outside the heart by the Vagus Nerve having parasympathetic activity on the sinoatrial nerve.

Stroke volume (taking contractility and Starling's law as one) are factors from the cardiac tissue itself - "intracardiac".

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Thank you for your fast and clear answer! – Masi Mar 9 '14 at 21:07

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