RESUMEN
<p><b>OBJECTIVE</b>To observe the effect of Wenxin Granule (WG) on brain natriuretic peptide (BNP) and heart rate variability (HRV) of acute coronary syndrome (ACS) patients.</p><p><b>METHODS</b>Totally 65 ACS patients were randomly assigned to the treatment group (35 cases) and the control group (30 cases). All patients were treated with routine therapies such as angiotensin conversing enzyme inhibitors (ACEI) and metoprolol. Those in the treatment group took WG, 9 g each time, three times daily. All were treated for 90 days. Plasma samples of BNP and HRV were determined before treatment and after treatment.</p><p><b>RESULTS</b>There was no statistical difference in pre-treatment plasma BNP (P > 0.05). Plasma BNP significantly decreased after treatment in the two groups when compared with before treatment (P < 0.05). The decrease was more obvious in the treatment group (P < 0.05). There was no statistical difference in pre-treatment HRV (P > 0.05). Compared with before treatment in the same group, RMSSD, PNN50%, and high frequency (HF) obviously increased, while low frequency (LF) and LF/HF ratio significantly decreased in the two groups, showing statistical difference (P < 0.05). The aforesaid indices were obviously better in the treatment group than in the control group (P < 0.05).</p><p><b>CONCLUSION</b>Additional administration of WG could improve short-term clinical prognosis by down-regulating plasma BNP level (via improving myocardial ischemia) and modulating HRV.</p>