changes in the neuroendocrine system in heart failure

Last reviewed 01/2018

The neuroendocrine systems which are most profoundly affected by heart failure are:

Renin-aldosterone system:

  • the renin-aldosterone system is inactive or only slightly activated in untreated heart failure
  • diuretics greatly stimulate renin production
  • angiotensin II increases peripheral vascoconstriction and hence the afterload on the heart
  • angiotensin II causes constriction of the efferent arteriole in the kidney:
    • in the normal kidney this may maintain the glomerular filtration rate in the face of reduced arterial blood pressure
    • in a kidney which is already dependent on angiotensin II e.g. in renal artery stenosis, further angiotensin II may cause reduced renal function
  • angiotensin II may be directly toxic to myocytes

Autonomic nervous system:

  • the sympathetic system is activated
  • the parasympathic tone is reduced
  • there is no good explanation for these changes
  • increased sympathetic activity may be detected by analysing heart rate variability
  • increased sympathetic activity is associated with fatal arrhythmias