Comparative Cardiac Effects of Chlorproguanil/Dapsone and Chloroquine during Treatment of Acute Uncomplicated Falciparum Malaria Infection in Nigerian Children

Cardiac toxicity has been reported with a number of antimalarial drugs. In this study we compared the cardiac effects of chlorproguanil/dapsone (CD) a new antimalarial drug, with that of chloroquine (CQ) during treatment of acute uncomplicated malaria in Nigeria. We monitored 62children with symptomatic malaria over 14 days by Clinical and electrocardiographic parameters. Thirty-one each received supervised dosing CD (daily for 3 days) or CQ (daily for 3 days). Clinical monitoring was done daily for 8 days and on day 14. Electrocardiographic monitoring was at 0hr, 4hrs, 24hrs, 30hrs, 48hrs, 54hrs, 72hrs, 96hrs, 120hrs, 144hrs, D7 and D14. Sinus tachycardia was the most often observed electrocardiographic abnormality pretreatment. Seven of twenty-eight (25%) children treated with CD in whom pre-treatment Q-Tc intervals were normal had lengthening of Q-Tc interval while 33.3% (9/27) of those treated with CQ had lengthening of Q-Tc interval. (P < 0.004, χ² test). Post-treatment Q-Tc interval prolongation was observed in 52% and 47.8% of children treated with CD and CQ respectively. Two patients who received CD recorded abnormally prolonged P-R interval (6.5%, P < 0.025; χ² test). One of the two patients developed primary A-V block between 96 hr and 168 hr. The second patient had occasional ventricular ectopic complexes at 54 hrs, 72 hrs and 96 hrs. There were no clinical symptoms in all the patients. The occurrence of rhythm disturbance in two of the patients who received CD may be pointers to possible cardiotoxic potentials of CD.