Tongmai Yangxin Pill combined with metoprolol or metoprolol alone for the treatment of symptomatic premature ventricular complex: a multicenter, randomized, parallel-controlled clinical study

OBJECTIVE: To investigate the effects of Tongmai Yangxin Pill (TMYXP) combined with metoprolol tartrate or metoprolol alone for the treatment of premature ventricular complex (PVC) in patients with symptomatic frequent PVC. METHODS: A total of 584 patients with symptomatic frequent PVC were randomly assigned (in a 1:1 ratio) into two groups: study group [n = 292, TMYXP (40 pills twice/day, orally) combined with metoprolol tartrate (25 mg twice/day, orally)] and control group [n = 292, metoprolol tartrate (25 mg twice/day, orally) plus placebo pill (40 pills twice/day, orally)]. The total treatment period was eight weeks. RESULTS: After eight weeks of treatment, the total effective rate of reduction of PVC in the study group and the control group were 76.4% and 51.4%, respectively (P < 0.001). TMYXP combined with metoprolol tartrate demonstrated a significantly greater reduction of the frequency of PVCs compared with the metoprolol tartrate alone (−4537 times/24 h vs. −3013 times/24 h, P < 0.001). The study group also showed a better result compared with the control group with respect to PVC related symptoms. In terms of New York Heart Association classification improvement, the total effective rates were 21.9% in the study group and 12.4% in the control group ( P < 0.05). Both the study group and the control group exhibited improvements in echocardiographic indexes. Left ventricular ejection fraction was significantly improved in the study group compared with the control group ( P < 0.05). There was no significant difference in the incidence of adverse events between the two groups. CONCLUSIONS: Compared with metoprolol tartrate alone, TMYXP combined with metoprolol tartrate could more effectively reduce the frequency of PVC and alleviated PVC related symptoms, and improve cardiac function in patients with symptomatic PVC.