The invention provides a use of landiolol hydrochloride as a sole treatment for the persistent reduction of the heart rate during the administration period of landiolol hydrochloride in the treatment of a human suffering from tachycardia, tachyarrhythmia or elevated blood pressure, wherein landiolol hydrochloride is administered at a constant dose of more than 20 μg/kg/min, but not higher than 40 μg/kg/min, for a period of from 2 to 20 hours and wherein the heart rate and/or blood pressure of said patient are persistently reduced during the administration period compared to the heart rate and/or blood pressure before treatment and no overshooting effect occurs after termination of said administration.
