Cardiotoxicity of antimalarial drugs.

Over the last few years, many severe cardiac side effects of antimalarial d rugs have been reported. Ventricular arrhythmias were the most frequent (ve ntricular premature beats, ventricular tachycardia, and torsades de pointes [polymorphic ventricular tachycardia]). These events occurred with most an timalarial drugs belonging to the aryl-amino-alcohol family including quini ne, mefloquine, and halofantrine. These agents have a biochemical structure , tissue distribution, and mechanism of action similar to those of quinidin e and Class I Vaughan-Williams antiarrythmic agents. All induced ECG QTc le ngthening. These cardiac complications occurred more frequently in the case of predisposing factors such as hypokalemia, bradycardia, and treatment wi th drugs modifying the QT interval. Atrial flutter was reported with mefloq uine and restrictive cardiomyopathy was described in long-course chloroquin e treatment at a higher dosage. No cardiac adverse event has yet been repor ted with such new antimalarial drugs as qinghaosu derivatives. Given this d ata concerning cardiac side effects, the authors have written out recommend ations for the prescription of antimalarial drugs. (C) 1999 Editions scient ifiques et medicales Elsevier SAS.