Open-Label Two-Dose Pilot Study of Landiolol for the Treatment of Atrial Fibrillation/Atrial Flutter in Caucasian Patients

BACKGROUND: We investigated for the first time the suitability of landiolol, an ultra-short-acting beta1-specific beta-blocker, for the treatment of atrial fibrillation/atrial flutter (AF/AFL) in Caucasian patients.Methods and Results:The 20 study patients received landiolol as a continuous infusion (starting dose 40 microg/kg/min) with (B+CI) or without (CI) a preceding bolus dose (100 microg/kg/min administered over 1 min) in a prospective open-label study. The primary endpoint was the proportion of patients with sustained heart rate (HR) reduction >/=20% or to <90 beats/min within 16 min of starting the CI. Secondary endpoints were the pharmacodynamics, pharmacokinetics, AF/AFL symptoms, safety and tolerability of landiolol. At 16 min, HR was reduced in all patients treated with landiolol. The primary endpoint was met by 60% of patients in the CI group and 40% in the B+CI group without a significant group difference. Overall reduction of AF/AFL symptoms at 16 min was 72%. Safety and local tolerability of landiolol were excellent, and no serious adverse events occurred. CONCLUSIONS: Continuous infusion of landiolol with a starting dose of 40 microg/kg/min is suitable for the acute treatment of tachycardic AF/AFL in Caucasian patients. Administration of a preceding bolus seems unnecessary.