Outcome measures
The data collection included the population and IH characteristics and the indication of treatment during the initial consultation. Patient follow-up included treatment initiation until the end of treatment.
We collected all data from patient monitoring (cardiac examination, echocardiogram, ECG, cardiac monitoring) before, during (at each titration stage for both conventional and rapid protocols), and after Hemangiol® initiation.
Parents of children under Hemangiol® were asked to call the paediatric cardiology 24-hour hotline for any clinical symptom. Therefore, we recorded all adverse events (AEs), defined as any undesirable experience possibly associated with the use of Hemangiol® from drug initiation and throughout the follow-up. Serious adverse events (SAEs) were defined as life-threatening events or adverse events leading to death, hospitalization, disability or permanent damage, intervention to prevent permanent impairment, or any important medical event as defined by the drug agencies. SAEs were reported to pharmacovigilance and causality was established using the standard method derived from Bégaud et al19. This algorithm is based on an intrinsic score including chronological and semiological criteria ranging from 0 to 6 (from absence to strong relationship between drug and the occurrence of adverse event; scores ≥2 indicating possible relation to treatment) and an extrinsic score based on bibliography20.