Effects of cisapride on ventricular depolarization-repolarization and arrhythmia markers in infants

S A Zamora1, D C Belli, G Ferrazzini

  • 1Gastroenterology, Department of Pediatrics, University Hospital, Geneva, Switzerland. Samuel.Zamora@hcuge.ch

Insights

Cisapride prolongs ventricular repolarization in neonates, increasing corrected QT interval (QTc). Researchers recommend limiting cisapride dosage to 0.8 mg/kg/day to mitigate risks.

Area of Science:

  • Neonatal cardiology
  • Pediatric electrophysiology
  • Pharmacology

Background:

  • Cisapride is used in neonates, but its effects on cardiac repolarization are not fully understood.
  • Ventricular repolarization abnormalities can increase arrhythmia risk in infants.

Purpose of the Study:

  • To prospectively evaluate cisapride's impact on ventricular repolarization, depolarization, and arrhythmia markers in neonates.
  • To assess changes in corrected QT interval (QTc), QT dispersion (QTd), and signal-averaged ECG parameters.

Main Methods:

  • Prospective study involving 35 neonates (term and preterm).
  • Standard ECGs and high-gain signal-averaged ECG (SAECG) were performed before and after cisapride administration (1 mg/kg/day).
  • Measured parameters included QTc, QTd, filtered QRS duration, LAS40, and RMS40.

Main Results:

  • Cisapride significantly lengthened the corrected QT interval (QTc) in neonates (p < 0.001).
  • QT dispersion (QTd) increased in infants with prolonged QTc.
  • No significant changes were observed in depolarization markers (fQRS, LAS40, RMS40).
  • 14% of infants had QTc > 450 ms after cisapride treatment.

Conclusions:

  • Cisapride prolongs ventricular repolarization in neonates and infants.
  • Depolarization parameters remained unaffected by cisapride.
  • A cisapride dosage of 0.8 mg/kg/day is recommended to minimize cardiac risks.

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