Inclusion Criteria:

• Males or females, age ≥ 18 years.
• Patients with an active Implantable Cardioverter Defibrillator (ICD).
• Left Ventricular Ejection Fraction (LVEF) ≤ 40%, measured within the past year (12 months).
• Able and willing to provide written informed consent before undergoing any study-related procedures.

Exclusion Criteria:

• Any condition that by the judgement of the physician investigator precludes the subject’s ability to comply with the study requirements.
• Any known skin allergy or sensitivity to the study garment materials that will be next to the skin.
• Any breached or compromised skin on the upper torso that would be exacerbated by wearing the study garment.
• Work with or are frequently around equipment that produces high electromagnetic fields, for example magnetic resonance imaging devices, power supply facilities, or welding equipment.
• Any planned surgical or medical procedures during the participation period.
• Any planned air travel during the participation period.
• Cognitive and/or physical limitations that would prevent the subject from interacting with the device as intended.
• Pregnancy.
• Use of mechanical circulatory support, for example Left Ventricular Assist Device (LVAD) or Total Artificial Heart.
• Implanted Cardiac Resynchronization Therapy Defibrillator (CRT-D).
• Pacing pulse width > 1ms.
• Simultaneous plan/prescription for Holter monitor, mobile cardiac outpatient telemetry (MCOT), Event Recorder, or in-hospital telemetry.
• Use of any electronic medical device that is worn on or near the body requires Sponsor approval, other than continuous positive airway pressure (CPAP), continuous blood glucose monitor, or pulse oximeter oxygen saturation (SpO2) monitor.