Wearable cardioverter defibrillator
A wearable cardioverter defibrillator (WCD) is a non-invasive, external device for patients at risk of cardiac arrest (SCA). It allows physicians time to assess their patient's arrhythmic risk and see if their ejection fraction improves before determining the next steps in patient care.
Source: Wikipedia — Wearable cardioverter defibrillator (CC BY-SA 4.0)