After-Load

• After-load:

  • a degree of emptying
  • determined by arterial blood pressure
• After-load:

  • after-load is the pressure (120 mmHG) that the heart has to eject blood against normally 80 mmHg in the aorta - ie diastolic BP
  • so normally after-load closely mirrors SBP and is not a major determinant of SV in health, but
  • increased pulmonary vascular resistance/increased blood pressure -> increase after-load
  • this is not sustainable as it means the heart is working harder than normal