The use of accelerometers to improve clinical outcomes in patients with implantable cardioverter defibrillators or at high risk of sudden cardiac death.

The Implantable Cardioverter-Defibrillator (ICD) is pivotal in preventing sudden cardiac death, monitoring cardiac activity, and restoring normal sinus rhythm with electrical shocks. With sudden cardiac death accounting for nearly half of all cardiac-related fatalities, ICDs significantly reduce mortality in high-risk patients. When integrated with accelerometers, ICDs also track physical activity (PA), which helps predict cardiac support needs and the likelihood of hospitalisation. Increased PA following ICD implantation has been associated with improved clinical outcomes. Wearable accelerometers show promise for assessing individual physical behaviour (PB), potentially serving as prognostic predictors of future cardiac events. This commentary critically evaluates the recent systematic review by Kolk et al. (2022), which examines the association between PB and key clinical outcomes in patients with ICD or at risk of sudden cardiac death.