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Impact of Intracardiac Neurons on Cardiac Electrophysiology and Arrhythmogenesis in an Ex Vivo Langendorff System
Published on: May 22, 2018
Autonomic pathophysiology in heart failure patients. Sympathetic-cholinergic interrelations
T R Porter1, D L Eckberg, J M Fritsch
1Department of Medicine, Veterans Administration Medical Center, Richmond Virginia.
The Journal of Clinical Investigation
|May 1, 1990
Summary
Heart failure patients exhibit heightened sympathetic and diminished vagal nerve activity. These autonomic nervous system imbalances, particularly reduced parasympathetic function, may stem from central nervous system abnormalities.
Area of Science:
- Cardiology
- Neuroscience
- Autonomic Nervous System Research
Background:
- Heart failure is associated with known sympathetic nervous system hyperactivity.
- Understanding the role of vagal nerve dysfunction in heart failure is crucial.
Purpose of the Study:
- To characterize and understand vagal abnormalities in heart failure patients.
- To investigate the relationship between sympathetic and parasympathetic activity at rest and after pharmacological intervention.
Main Methods:
- Measured peroneal nerve muscle sympathetic activity and plasma norepinephrine levels.
- Assessed vagal activity via R-R intervals and their standard deviations.
- Administered parasympathomimetic and parasympatholytic doses of atropine sulfate to eight heart failure patients and eight healthy volunteers.
Main Results:
- Heart failure patients displayed high sympathetic and low parasympathetic (vagal) outflows at rest.
- Healthy subjects showed the opposite pattern: low sympathetic and high parasympathetic outflows.
- Low-dose atropine increased R-R intervals in healthy subjects but not in heart failure patients, indicating impaired vagal response.
Conclusions:
- Heart failure is characterized by reciprocal supranormal sympathetic and subnormal parasympathetic (vagal) outflows.
- These autonomic abnormalities in heart failure likely originate, in part, from central nervous system dysfunction.
- The findings highlight significant vagal nerve impairment in heart failure.
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