Cardiac effects of standard-dose halofantrine therapy.
The antimalarial drug halofantrine hydrochloride has been associated with cardiac arrhythmias. This is a report of a study on the cardiac effects of standard-dose halofantrine (24 mg/kg) on a sample of 48 patients selected from a group of 402 Dega (Montagnard) refugees treated for Plasmodium falciparum infection. Prolongation of the rate-corrected QT interval (QTc) on the electrocardiogram (ECG) was used as an indicator of risk for halofantrine-associated cardiac arrhythmias. We found that standard-dose halofantrine was associated with a lengthening of the mean QTc from 0.04 sec(1/2) to 0.44 sec(1/2). Two patients had a QTc increase of greater than 25%, but none had a follow-up QTc of more than 0.55 sec(1/2), an interval length generally considered to be a risk factor for ventricular arrhythmias. Regression analysis indicated that pretreatment ECGs were poorly predictive of QTc lengthening during therapy, although pretreatment ECGs may be useful to evaluate patients with pre-existing cardiac conditions. The manufacturer has recommended that the halofantrine dose not exceed 24 mg/kg and revised the list of medication contraindications to include some cardiac conditions. Clinicians should weigh a patient's risk, including history of cardiac disease and availability of alternative therapy before use of halofantrine.
Matson
P A
PA
Division of Field Epidemology, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
Luby
S P
SP
Redd
S C
SC
Rolka
H R
HR
Meriwether
R A
RA
D000293:Adolescent; D000328:Adult; D000368:Aged; D000962:Antimalarials / Q000009:adverse effects* / Q000627:therapeutic use; D001145:Arrhythmias, Cardiac / Q000139:chemically induced* / Q000208:ethnology; D004562:Electrocardiography; D005260:Female; D006321:Heart / Q000187:drug effects*; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D016018:Least-Squares Analysis; D016778:Malaria, Falciparum / Q000188:drug therapy* / Q000208:ethnology; D008297:Male; D008875:Middle Aged; D010616:Phenanthrenes / Q000009:adverse effects* / Q000627:therapeutic use; D012036:Refugees; D014744:Vietnam / Q000208:ethnology
D000962:Antimalarials; D010616:Phenanthrenes; C023768:halofantrine