Background Shen song Yang xin （SSYX） is a compound of Chinese medicine with the effect of increasing heart rate （HR）. This study aimed to evaluate its electrophysiological properties at heart and cellular levels. ...Background Shen song Yang xin （SSYX） is a compound of Chinese medicine with the effect of increasing heart rate （HR）. This study aimed to evaluate its electrophysiological properties at heart and cellular levels. Methods The Chinese miniature swines were randomly assigned to two groups, administered with SSYX or placebo for 4 weeks （n=8 per group）. Cardiac electrophysiological study （EPS） was performed before and after drug administration. The guinea pig ventricular myocytes were enzymatically isolated and whole cell voltage-clamp technique was used to evaluate the effect of SSYX on cardiac action potential （AP）. Results SSYX treatment accelerated the HR from （141.8±36.0） beats per minute to （163.0±38.0） beats per minute （P=0.013） without changing the other parameters in surface electrocardiogram. After blockage of the autonomic nervous system with metoprolol and atropin, SSYX had no effect on intrinsic HR （IHR）, but decreased corrected sinus node recovery time （CSNRT） and sinus atrium conducting time （SACT）. Intra cardiac EPS showed that SSYX significantly decreased the A-H and A-V intervals as well as shortened the atrial （A）, atrioventricular node （AVN） and ventricular （V） effective refractory period （ERP）. In isolated guinea pig ventricular myocytes, the most obvious effect of SSYX on action potential was a shortening of the action potential duration （APD） without change in shape of action potential. The shortening rates of APD30, APD50 and APD9o were 19.5%, 17.8% and 15.3%, respectively. The resting potential （Em） and the interval between the end of APD30 and APD90 did not significantly change. Conclusions The present study demonstrates that SSYX increases the HR and enhances the conducting capacity of the heart in the condition of the intact autonomic nervous system. SSYX homogenously decreases the ERP of the heart and shortens the APD of the myocytes, suggesting its antiarrhythmic effect without proarrhythmia.展开更多
Atrial fibrillation （AF） is the most common type of arrhythmia, which is reported to increase the incidence of stroke by five to seven tblds, leading to the irregular ventricular rhythm and adversely impacted life q...Atrial fibrillation （AF） is the most common type of arrhythmia, which is reported to increase the incidence of stroke by five to seven tblds, leading to the irregular ventricular rhythm and adversely impacted life quality, and the mortality could be increased as well by AF per se. Shen Song Yang Xin （SSYX） capsule is a novel traditional Chinese medicine composed of more than a dozen Chinese medicine herbs with significant antiarrhythmic effect. In the current study, the effect of SSYX capsule has been tested in an animal study and it was also indicated by randomized double-blinded, positive drug-controlled clinical trials, However, the working mechanism of SSYX capsule as antiarrhythmic drug is not completely clear yet. This study tried to investigate the effect of SSYX capsule on the myocardial electrophysiology of acute AF dog model.展开更多
文摘Background Shen song Yang xin （SSYX） is a compound of Chinese medicine with the effect of increasing heart rate （HR）. This study aimed to evaluate its electrophysiological properties at heart and cellular levels. Methods The Chinese miniature swines were randomly assigned to two groups, administered with SSYX or placebo for 4 weeks （n=8 per group）. Cardiac electrophysiological study （EPS） was performed before and after drug administration. The guinea pig ventricular myocytes were enzymatically isolated and whole cell voltage-clamp technique was used to evaluate the effect of SSYX on cardiac action potential （AP）. Results SSYX treatment accelerated the HR from （141.8±36.0） beats per minute to （163.0±38.0） beats per minute （P=0.013） without changing the other parameters in surface electrocardiogram. After blockage of the autonomic nervous system with metoprolol and atropin, SSYX had no effect on intrinsic HR （IHR）, but decreased corrected sinus node recovery time （CSNRT） and sinus atrium conducting time （SACT）. Intra cardiac EPS showed that SSYX significantly decreased the A-H and A-V intervals as well as shortened the atrial （A）, atrioventricular node （AVN） and ventricular （V） effective refractory period （ERP）. In isolated guinea pig ventricular myocytes, the most obvious effect of SSYX on action potential was a shortening of the action potential duration （APD） without change in shape of action potential. The shortening rates of APD30, APD50 and APD9o were 19.5%, 17.8% and 15.3%, respectively. The resting potential （Em） and the interval between the end of APD30 and APD90 did not significantly change. Conclusions The present study demonstrates that SSYX increases the HR and enhances the conducting capacity of the heart in the condition of the intact autonomic nervous system. SSYX homogenously decreases the ERP of the heart and shortens the APD of the myocytes, suggesting its antiarrhythmic effect without proarrhythmia.
文摘Atrial fibrillation （AF） is the most common type of arrhythmia, which is reported to increase the incidence of stroke by five to seven tblds, leading to the irregular ventricular rhythm and adversely impacted life quality, and the mortality could be increased as well by AF per se. Shen Song Yang Xin （SSYX） capsule is a novel traditional Chinese medicine composed of more than a dozen Chinese medicine herbs with significant antiarrhythmic effect. In the current study, the effect of SSYX capsule has been tested in an animal study and it was also indicated by randomized double-blinded, positive drug-controlled clinical trials, However, the working mechanism of SSYX capsule as antiarrhythmic drug is not completely clear yet. This study tried to investigate the effect of SSYX capsule on the myocardial electrophysiology of acute AF dog model.
