Tolerability of beta-blocker initiation and titration with bisoprolol and carvedilol in congestive heart failure -- a randomized comparison

In clinical trials beta-blockers (BB) are well tolerated in patients with systolic congestive heart failure (CHF). In contrast, in daily practice treatment initiation and titration appear to be more difficult and may differ in various BB -- but systematic data are lacking. We randomized 87 patients with systolic CHF (mean age 70.1 +/- 10.6 years, 24% females, LVEF 0.28 +/- 0.10, NYHA III-IV 29%) to treatment with either bisoprolol or carvedilol, in order to assess and compare the maximally achievable number of patients on treatment with these BB and the maximally achieved dosage during a minimum of 2 months attendance at our out patient heart failure clinic. In those randomized to bisoprolol, mean dose at 2 months was 33% of target dose (3.1 +/- 2.6 mg) and 41% at discharge. In those on carvedilol, the mean dose at 2 months was 27% of target dose (13.4 +/- 14.0 mg) and 32% at discharge. Thirty-nine and 40% of the bisoprolol and carvedilol treated patients, respectively, had stopped treatment at discharge. None of the figures differed significantly between the two treatment groups and no baseline parameter predicted BB tolerability. Thus, almost twice the number of unselected patients with systolic CHF attending a heart failure clinic focusing on systematic medical titration were intolerant to BB treatment and only a minority reached target dose treatment. The present data reveal no clear difference with respect to tolerability of carvedilol and bisoprolol, and no parameter predicts tolerability.