It has been reported that berberine is valuable for long-term treatment of ventricular premature beats (VPBs) and leads to a decrease in mortality for patients with congestive heart failure (CHF). In order to improve its therapeutic value and reduce its side effects, it is necessary to study the relationship between its activity and plasma concentration in patients with CHF. Patients with CHF were treated with conventional therapy for 2 weeks. Immediately after the data from a dynamic electrocardiogram (DCG) and left ventricular ejection fraction (LVEF) were obtained, 1.2 g/day of oral berberine was given. After 2 weeks of berberine therapy, the DCG data and LVEF were reassessed and the plasma berberine concentration was measured by HPLC. Plasma samples were pretreated by extraction with chloroform. Berberine in all samples was determined using a mu Bondapak C(18) column, a mobile phase of acetonitrile:0.02 mol/L phosphoric acid (45:55, v/v), and a UV detector at 346 nm. The mean recovery was 96.5%. The linear range was 40-1600 ng/mL. The detection limit for berberine in plasma was 0. 4 ng. The decrease in frequency and complexity of VPBs and the increase in LVEF in patients with plasma berberine concentrations higher than 0.11 mg/L (n = 31, group B) were more significant than at concentrations lower than 0.11 mg/L (p < 0.01 vs p < 0.05).
Copyright 1999 John Wiley & Sons, Ltd.