Bisoprolol improves survival in rats with heart failure

The cardioprotective effects of bisoprolol were studied in a rat model of severe heart failure induced by autoimmune myocarditis. Twenty-eight days after immunization, Lewis rats were divided into four groups: 0.1 mg/kg/day bisoprolol (Group 0.1), 1.0 mg/kg/day bisoprolol (Group 1) and 10 mg/kg/day bisoprolol (Group 10), and vehicle (0.5% methylcellulose; Group V) (all groups, n = 13). After oral administration for I month, heart weight, mean blood pressure, heart rate, central venous pressure, peak left ventricular pressure, left ventricular end-diastolic pressure, ± dP/dt, and area of fibrosis were measured. Although bisoprolol reduced heart rate (399 ± 11/min in Group V. 382 ± 10/min in Group 0.1. 348 ± 8/min in Group I and 302 ± 9/min in Group 10) and increased survival (62% in Group V. 69% in Group 0.1, and 100% in Group 1 and Group 10) in a dose-dependent manner, this drug did not change heart weight, the area of myocardial fibrosis or hemodynamic parameters. These observations suggested that bisoprolol may improve survival independently of its effect on left ventricular function by reducing sudden death in patients with severe heart failure.