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Impact of Intracardiac Neurons on Cardiac Electrophysiology and Arrhythmogenesis in an Ex Vivo Langendorff System
Published on: May 22, 2018
Influence of racemic higenamine on the sinus node
Fengxia Yu1, Lingting Kong, Shujuan Wang
1Department of Emergency Medicine, Yantaishan Hospital, Yantai, Shandong 264001, P.R. China.
Experimental and Therapeutic Medicine
|February 14, 2013
Summary
Racemic higenamine effectively treats sick sinus syndrome (SSS) by improving heart rhythm. This study found it enhances sinus node function and conduction in damaged sinus node models.
Area of Science:
- Cardiology
- Pharmacology
- Electrophysiology
Background:
- Sick sinus syndrome (SSS) is a condition affecting heart rhythm.
- Understanding treatment mechanisms for SSS is crucial.
Purpose of the Study:
- To investigate the electrophysiological mechanism of racemic higenamine in treating sick sinus syndrome (SSS).
Main Methods:
- 40 New Zealand rabbits were used, divided into normal and damaged sinus node (SND) groups.
- The SND model was created using formaldehyde.
- Rabbits received intravenous racemic higenamine (0.04 mg/kg) or saline, with electrophysiological indicators measured.
Main Results:
- Racemic higenamine significantly shortened sinus node recovery time (SNRT), corrected SNRT (CSNRT), total sinoatrial conduction time (TSACT), and sinus cycle length (SCL) in both groups.
- The drug's effect was more pronounced in the SND group.
- Racemic higenamine demonstrated a statistically significant effect in treating SSS-related arrhythmias.
Conclusions:
- Racemic higenamine enhances sinus node automaticity and improves sinoatrial and atrioventricular conduction.
- These actions constitute the primary electrophysiological mechanism for its therapeutic effect in SSS.
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