Beat to Beat A Prospective Study in Paediatric, Adolescent and Young Adult Patients Aged 7 to 18 Years of Age Who Are Undergoing or Have Undergone Cancer Therapy to Evaluate the Agreement Between QTc Measured Using 12 Lead Electrocardiogram (ECG) and a Wearable Device ECG

Rationale: Leveraging existing wearable technology has the ability to scale routine screening strategies across large populations and can facilitate ambulatory care. In recent years, wearable technology has rapidly diffused into consumer markets and provides unique opportunities to engage individuals on health issues of personal interest, and to collect personal health data. One example of such technology is the ability to perform electrocardiogram (ECG) type traces on wearable devices. However, utilization of this data source to improve patient outcomes has not been fully realized in the health care field. An app-based heart ECG algorithm that can be remotely analysed for QTc prolongation with potential to then notify the user of such potential irregularities could lead to widespread screening, detection and initiation of treatment solutions (i.e. correction of electrolytes, alteration of exacerbating medications, cardiac monitoring etc).

Trial Design: This will be a prospective, single arm, experimental, non-significant risk study conducted with the assistance of eligible participants. Parents or mature minors will download the Beat to Beat app, once consented.

Once consented the wearable device will be paired to the parent/guardians phone following the steps provided by the wearable device app. Once the device is paired and the study coordinator has assisted with the download of 'Beat to Beat' app, the patients will then be able to commence the ECG readings. A 12 lead ECG will be performed by the study team and immediately following this, an ECG will be recorded on the wearable device. The wearable device will be placed on the left wrist for a Lead I reading, on the left lower abdomen for a Lead II reading and in the fourth intercostal space left parasternal for a chest V2 Lead reading. Recording of the 12 lead ECG and wearable device ECG will be repeated again 4 days later. Once both timepoints (and two device recordings for each time period) have been completed the ECGs will be retrieved from the Beat to Beat app. Both the 12 lead and wearable device ECG will be de-identified and given a patient identifier before being uploaded into the REDCap database.