Haemodynamic Responses to Exercise in Hypertension: Place of the Sympathetic Nervous System Evaluated by a New Selective Cardiac Beta-adrenergic Blocking Agent ICI 50,172

Intravenous administration of a new cardio-selective β-adrenergic blocking agent with intrinsic sympathetic activity, but, unlike propranolol, with no quinidine-like activity, produced insignificant haemodynamic effects at rest. On treadmill exercise, however, blood pressure, heart rate, cardiac output, and left ventricular work were reduced, peripheral resistance remaining unaltered.