Dose-finding study of landiolol hydrochloride: a short-acting β1-blocker for controlling heart rate during coronary computed-tomography angiography in Japan.
BACKGROUND
Coronary computed-tomography angiography (CCTA) has high diagnostic performance, but it sometimes does not allow evaluation because of artifacts. Currently, the use of a β-blocker is recommended to prevent motion artifacts, but the β-blocker (metoprolol, propranolol, etc.) commonly used has a slow onset and long duration of action. Landiolol hydrochloride is an intravenous β1-blocker with a very short half-life. We investigated the efficacy and optimal dose of this drug for reduction of heart rate in patients undergoing CCTA.


METHODS
Eighty-seven subjects with ischemic heart disease were divided into three groups to receive landiolol hydrochloride at a dose of 0.125 (Group L), 0.25 (Group M), or 0.5 mg/kg (Group H). CCTA was performed at 3-7 min after administration, and heart rate, blood pressure, and image quality were assessed.


RESULTS
Heart rate decreased rapidly after completion of landiolol hydrochloride administration in all groups, with a heart rate reduction of 15.55 ± 6.56% in Group L, 16.48 ± 7.80% in Group M, and 21.49 ± 6.13% in Group H (Group L vs Group H, P = 0.0008; Group M vs Group H, P = 0.0109). Since there was no significant difference in heart rate during imaging among the three groups, although there was a significant difference between groups L and H and groups M and H in terms of percent change in heart rate, coronary stenosis was diagnosable in all groups with no significant difference.


CONCLUSIONS
Landiolol hydrochloride showed a rapid onset and short β-blocking effect, and was most effective at a dose of 0.5 mg/kg. However, the diagnosable proportion had no significant differences among the three groups in CCTA. Therefore, the clinically recommended dose was 0.125 mg/kg or less, considering the heart rate of patients with suspected coronary stenosis during CCTA.
Department of Cardiology, Tokyo Medical University, 6-7-1, Nishi-shinjuku, Shinjuku-ku, Tokyo, 160-0023, Japan, m-hirano@tokyo-med.ac.jp.
Masaharu
M
Hirano
Kazuhiro
K
Hara
Yuji
Y
Ikari
Masahiro
M
Jinzaki
Misako
M
Iino
Chikuma
C
Hamada
Sachio
S
Kuribayashi
D058671:Adrenergic beta-1 Receptor Antagonists / Q000008:administration & dosage*; D000368:Aged; D016477:Artifacts; D001794:Blood Pressure; D017023:Coronary Angiography / Q000379:methods*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006339:Heart Rate / Q000187:drug effects*; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D009025:Morpholines / Q000008:administration & dosage*; D061330:Multidetector Computed Tomography / Q000379:methods; D017202:Myocardial Ischemia / Q000175:diagnosis / Q000000981:diagnostic imaging*; D014508:Urea / Q000008:administration & dosage / Q000031:analogs & derivatives*
D058671:Adrenergic beta-1 Receptor Antagonists; D009025:Morpholines; C077049:landiolol; D014508:Urea