Objectives: To elucidate pharmacokinetics and pharmacodynamics of landiolol hydrochloride, newer developed ultra-short-acting beta-blocker, in patients with various cardiac tachyarrhythmias.
Background: The short duration of action and titratability of landiolol hydrochloride make it ideal for use in patients with a clinical need for beta-blockers.
Methods: In a total of 31 examinations we infused the drug in 19 patients (mean age, 55 +/- 14 years). After the persistence of the tachyarrhythmias was confirmed, continuous infusion was started at rates of 0.005, 0.01, 0.02, 0.04, and 0.08 mg/kg/min for 5 minutes (for paroxysmal atrial fibrillation, paroxysmal supraventricular tachycardia, and ventricular tachycardia) or 15 minutes (for ventricular premature complex). We analyzed the pharmacokinetics of 16 examinations. A one-compartment model provided a close fit for each blood concentration-time curve.
Results: The maximum blood concentrations obtained clearly showed the dose dependency and revealed very short half-lives (range, 2.3 to 4.0 minutes). Area under the blood concentration-time curves also increased, showing dose dependency. In paroxysmal atrial fibrillation, landiolol hydrochloride reduced the heart rate from 111 +/- 20 to 90 +/- 10/min. Sinus rhythm was restored, without any adverse effects, in three of five patients with paroxysmal supraventricular tachycardia and one patient with ventricular tachycardia. There was no significant change in peripheral blood pressure.
Conclusions: Landiolol hydrochloride has a shorter elimination half-life than any other beta-blocker, and it can be administered safely to patients with various tachyarrhythmias.