Objective

2

To evaluate the clinical efficacy and safety of

Tongyang Huoxue Granules

in the treatment of sick sinus syndrome （SSS）.

Methods

2

A total of 80 patients with

yang

deficiency and blood stasis type SSS admitted to Guang'anmen Hospital， China Academy of Chinese Medical Sciences from December 2018 to September 2020 were enrolled and randomly assigned to an observation group and a control group using simple block randomization， with 40 patients in each group. The observation group received

Tongyang Huoxue Granules

（12 g/time， 2 times/day） orally， while the control group received theophylline sustained-release tablets （0.1 g/time， 2 times/day） orally. Both groups were treated for 4 weeks and followed up for 6 months. Traditional Chinese medicine （TCM） syndrome scores， 24-hour dynamic electrocardiogram parameters ［total heart rate， average heart rate， fastest heart rate， slowest heart rate， percentage of heartbeats with adjacent sinus RR interval difference

>

50 ms to total sinus RR interval beats （PNN50）， standard deviation of RR interval mean （SDANN）， standard deviation of 24-hour sinus RR intervals （SDNN）， root mean square of successive normal RR interval differences （RMSSD）］， resting heart rate， safety indicators ［alanine aminotransferase （ALT）， aspartate aminotransferase （AST）， serum creatinine （SCr）， blood urea nitrogen （BUN）］， and adverse events were compared before and after treatment.

Results

2

After treatment， TCM syndrome scores in the observation group decreased compared with baseline （

P

<

0.05）. In the control group， scores for palpitations， chest tightness， shortn

ess of breath and fatigue， chest pain， cold limbs， dizziness， tinnitus， pulse， and total scores decreased compared with baseline （

P

<

0.05）. Compared with the control group after treatment， the observation group had significantly lower scores for palpitations， chest tightness， shortness of breath and fatigue， chest pain， pale complexion， dizziness and tinnitus， lip cyanosis， tongue and pulse， and total scores （

P

<

0.05）. There were no significant differences between groups in total heart rate， average heart rate， fastest heart rate， or slowest heart rate before and after treatment （

P

>

0.05）. After treatment， total heart rate， average heart rate， fastest heart rate， and slowest heart rate increased in both groups compared with baseline （

P

<

0.05）. Heart rate variability indices showed no significant differences between groups before and after treatment （

P

>

0.05）. In the observation group， PNN50 decreased compared with baseline （

P

<

0.05）， and resting heart rate increased （

P

<

0.05）. No significant changes in ALT， AST， BUN， or SCr were observed before or after treatment in either group. No adverse events occurred during treatment or follow-up.

Conclusion

2

Tongyang Huoxue Granules

can increase heart rate， improve clinical symptoms， and are safe in patients with

yang

deficiency and blood stasis type SSS.