7220 Effects of cisapride on corrected qt interval, heart rate and rhythm in infants undergoing polysomnography.

Abstract

Objectives: to evaluate the effects of cisapride, a prokinetic gastrointestinal drug, on the electrocardiographic QT interval, heart rate and rhythm in infants during 8 hour polysomnography. Reported ECG and rhythm disturbances in a small number of patients with the use of cisapride provided the impetus for this prospective study. Study design: 277 infants were enrolled. Of these,150 were on cisapride therapy and 127, not on cisapride, served as controls. Cisapride treated and control infants were divided into 3 age groups; group 1: under 3 months of age; group 2: between 3 to 6 months of age and group 3: beyond 6 months. Continuous ECG bipolar limb lead I recording, saturation monitoring, and electroencephalography were carried out. QT intervals, and heart rate were measured at hourly intervals. Results: Cisapride doses were: group 1 mean 0.80 mg/kg/day (range 0.35 1.55), group 2 mean 0.80 mg/kg/day (range 0.23 1.38) and group 3 mean 0.72 mg/kg/day (range 0.32 1.41). Heart rate was higher in the younger infants, with a gradual decrement with age. No difference in heart rate was detected between the cisapride and control groups. A statistical significant increase in QTc was found in the group I cisapride patients as compared to controls (p< 0.001) when applying both the Bazett and Hodges Formulae for QT correction. The other age groups did not differ. No arrhythmia or atrioventricular conduction abnormalities were observed. Conclusion: infants under 3 months on cisapride treatment had significant QTc prolongation (with the Bazett formula, the 98th percentile was 500 ms in the cisapride group versus 447 ms in controls). The clinical significance and risk of the increased QTc interval in these infants is unclear and needs further evaluation and risk stratification. Meanwhile, cisapride should be judiciously prescribed in infants under the age of 3 months. Objectives: to evaluate the effects of cisapride, a prokinetic gastrointestinal drug, on the electrocardiographic QT interval, heart rate and rhythm in infants during 8 hour polysomnography. Reported ECG and rhythm disturbances in a small number of patients with the use of cisapride provided the impetus for this prospective study. Study design: 277 infants were enrolled. Of these,150 were on cisapride therapy and 127, not on cisapride, served as controls. Cisapride treated and control infants were divided into 3 age groups; group 1: under 3 months of age; group 2: between 3 to 6 months of age and group 3: beyond 6 months. Continuous ECG bipolar limb lead I recording, saturation monitoring, and electroencephalography were carried out. QT intervals, and heart rate were measured at hourly intervals. Results: Cisapride doses were: group 1 mean 0.80 mg/kg/day (range 0.35 1.55), group 2 mean 0.80 mg/kg/day (range 0.23 1.38) and group 3 mean 0.72 mg/kg/day (range 0.32 1.41). Heart rate was higher in the younger infants, with a gradual decrement with age. No difference in heart rate was detected between the cisapride and control groups. A statistical significant increase in QTc was found in the group I cisapride patients as compared to controls (p< 0.001) when applying both the Bazett and Hodges Formulae for QT correction. The other age groups did not differ. No arrhythmia or atrioventricular conduction abnormalities were observed. Conclusion: infants under 3 months on cisapride treatment had significant QTc prolongation (with the Bazett formula, the 98th percentile was 500 ms in the cisapride group versus 447 ms in controls). The clinical significance and risk of the increased QTc interval in these infants is unclear and needs further evaluation and risk stratification. Meanwhile, cisapride should be judiciously prescribed in infants under the age of 3 months.