The invention provides a new use of landiolol hydrochloride for 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 5 μg/kg/min, specifically of at least 10 μg/kg/min for a period of at least 2 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.