Acute Hemodynamic Effects of Ivabradine in Pediatric Cardiac Critical Care Patients.

BACKGROUND

Utilization of ivabradine in the pediatric population has been centered on the goal of chronotropic control in patients with arrhythmias and heart failure. Tachycardia is known to be detrimental when it impairs hemodynamics by increasing myocardial oxygen demand, increasing ventricular end-diastolic pressures, and decreasing cardiac output in certain patients. The acute hemodynamic effects of ivabradine have not yet been studied in real time.

STUDY QUESTION: This study was performed leveraging the Sickbay platform (Medical Informatics Company, Houston, TX). The primary aim of this study was to characterize the effect of enteral ivabradine on heart rate in patients in a pediatric cardiac intensive care unit within 24 hours of initiation. Secondary aims were to characterize the effects of ivabradine on arterial saturation, respiratory rate, mean arterial blood pressure, central venous pressure, and renal near infrared spectroscopy for the same time frame.

RESULTS

Heart rate decreased approximately 17% in the first 15 hours after ivabradine administration. Changes were seen in the secondary aims that varied depending on time after first and second doses. Specifically, decreases in central venous pressure and increased renal tissue oxygen saturation (rSO2) were observed by the end of the 24 hours.

CONCLUSIONS

Ivabradine seems safe in pediatric patients. It is associated with 3 distinct hemodynamic response phases: the first phase is associated with decreased heart rate and unchanged systemic oxygen delivery, the second phase is associated with increased heart rate and worsened systemic oxygen delivery, and the third phase being associated with decreased heart rate and improved systemic oxygen delivery. These phases coincide with the pharmacokinetic properties of ivabradine.