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Published on: December 2, 2014
Sympathetic activation in congestive heart failure.
1Department of Internal Medicine, University of Milan, Italy.
European Heart Journal
|April 1, 1990
Summary
Congestive heart failure involves increased sympathetic nerve activity that initially compensates but later worsens the condition. This sympathetic overactivity, linked to impaired reflexes, can be reduced by certain therapies.
Area of Science:
- Cardiology
- Neuroscience
- Physiology
Background:
- Congestive heart failure (CHF) is associated with heightened sympathetic nerve activity.
- This sympathetic activation may start early in the disease and worsen as CHF progresses.
Purpose of the Study:
- To review evidence linking sympathetic nerve activity to CHF progression and prognosis.
- To explore the mechanisms behind excessive sympathetic activation in CHF.
- To examine therapeutic interventions targeting sympathetic overactivity in CHF.
Main Methods:
- Literature review of studies on sympathetic nerve activity in congestive heart failure.
- Analysis of the role of baroreflex and cardiopulmonary reflex sensitivity.
- Examination of interactions between sympathetic and renin-angiotensin systems.
Main Results:
- Sympathetic overactivity in CHF initially compensates but becomes detrimental.
- Reduced sensitivity of cardiovascular reflexes (functional reflex denervation) contributes to excessive sympathetic drive.
- Interactions with the renin-angiotensin system exacerbate sympathetic activation.
- Therapies, like digitalis, can decrease sympathetic activation and improve reflex sensitivity.
Conclusions:
- Increased sympathetic nerve activity is a hallmark of CHF, progressing with disease severity.
- Mechanisms include impaired reflex control and neurohormonal interactions.
- Therapeutic strategies can modulate sympathetic overactivity and improve cardiovascular reflex function in CHF.
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