Sympathetic modulation in practice: the German clinical experience.

Xamoterol is a beta 1-selective adrenoceptor partial agonist. The acute effects of xamoterol were studied in 30 patients with ischaemic heart failure. Haemodynamic data were assessed at baseline, at rest and after supine bicycle exercise (50 W for 3 min), and repeated 15 min after xamoterol (0.2 mg kg-1) given by infusion over 5 min. At rest, xamoterol increased heart rate, mean blood pressure and cardiac index, and reduced pulmonary wedge pressure. On exercise, heart rate fell while cardiac index was maintained and pulmonary wedge pressure fell slightly but significantly. There was a tendency for plasma renin activity and plasma noradrenaline to fall both at rest and on exercise. The clinical relevance of these haemodynamic and neurohumoral changes were examined in conjunction with the German-Austrian Xamoterol Group's study, screening 443 patients with mild to moderate heart failure and giving xamoterol or placebo for 3 months as part of a randomized, double-blind study. The German experience was then placed in context of the pooled world-wide database of efficacy and safety in three other large (greater than 100 patients) studies with xamoterol in mild to moderate heart failure. In brief, this overview demonstrated a 2.98 +/- 0.68 kJ improvement in work done over placebo, equivalent to 14% (xamoterol) and 6% (placebo) improvements over baseline (P less than 0.0001). Xamoterol is thus a promising new approach to the treatment of mild to moderate heart failure.