Health Electronic Assessment of Risks and Trends using Biometric Equipment and Technology (HEARTBEAT): study design and rationale.

AIMS: Cardiovascular disease remains the leading driver of morbidity and mortality worldwide. As consumer smartwatches become ubiquitous, they offer a practical platform for continuous, real-world phenotyping, capturing passive and active biometrics that may detect occult disease and anticipate adverse cardiovascular events. Scaled deployment of these devices could enable remote screening, longitudinal monitoring, and earlier risk mitigation beyond traditional episodic care. METHODS AND RESULTS: The Health Electronic Assessment of Risks and Trends using Biometric Equipment and Technology (HEARTBEAT) study is a prospective, single-arm wearable study that has enrolled 897 participants since 10 October 2024. The primary objectives are to: (1) define associations between smartwatch-derived biometrics and incident cardiovascular events; (2) derive biometric profiles that support identification of underlying cardiometabolic and cardiovascular conditions; and (3) apply artificial intelligence to improve prediction of cardiovascular events. Participants are screened, consented, and enrolled in person or remotely. Data are captured through electronic medical record (EMR) extraction and a companion smartphone application. Participants are followed for 12 months, with outcomes adjudicated on an ongoing basis using EMR review and app-based surveys. CONCLUSION: The HEARTBEAT study will test whether scalable, consumer-grade wearables can move from wellness tracking to clinically meaningful signal, identifying comorbidities and predicting adverse cardiovascular outcomes in routine care settings. If successful, the study will help establish an evidence base for smartwatches as validated digital health tools for remote screening and continuous cardiovascular monitoring.