Inclusion Criteria:  Patients of any gender aged ≥ 18 years.  Patients with either:  a measured LVEF less than or equal to 40% (as assessed by techniques such as, but not limited to, cardiac angiography, echocardiography, magnetic resonance imaging, or radionuclide angiography within the last 30 days prior to enrollment) AND identified as presenting with a diagnosis of an AMI, ischemic cardiomyopathy (includes congestive heart failure: NYHA Class I - III), non- ischemic cardiomyopathy, or myocarditis;  OR  who have a temporary or long-term contraindication to receiving an ICD, who have had an ICD removed, or who refuse an ICD  OR  whose ICD implantation is delayed due to COVID-19 infection or exposure- related risks  Exclusion Criteria:  Member of a vulnerable patient population as defined in ISO 14155; Life expectancy of less than one year, including end-stage heart failure, cancer, or other diagnosed condition; Patients with an anticipated initial prescription period over 180 days (limitation only to allow timely closure of this clinical trial); Patients with an advanced directive prohibiting resuscitation; Existing ICD; Existing unipolar pacemaker; Existing FDA-cleared or FDA-approved active implantable or body worn medical device(s) that the Sponsor requires to be removed prior to the study but which cannot be removed; Clinically significant valve disease, including aortic stenosis, mitral stenosis; mitral regurgitation, tricuspid regurgitation, insufficiency of the aortic or pulmonary valves, any of which is likely to require surgery in the next year; A planned procedure, such as Coronary Artery Bypass Graft, within six (6) months; End-stage renal disease, or chronic renal failure requiring hemodialysis; Planned discharge to an institutional setting with an anticipated stay of greater than seven (7) days; Having a mental, visual, physical, or auditory deficit, that could impair their ability to properly place, remove, or interact with the Jewel System; Unable to understand English for the purposes of interacting with the device; Unable to use a wearable defibrillator due to physical conditions (bandages preventing electrode contact, physical deformities preventing electrode contact, etc.); Dextrocardia; Body circumference of less than 27 inches or greater than 56 inches in the intended area of the Belt component of the Placement Accessory; Participation in an investigational study of a drug, biologic, or device not currently approved for marketing; Allergic to or have had a known adverse reaction to medical adhesives or hydrocolloids; Active skin breakdown, erythema, or other signs of infection in the pectoral or torso regions where the Adhesive Electrode Patches are applied; Females who are pregnant or breast-feeding, or planning to be pregnant in the next 12 months; No US-based postal address that can be used to ship and receive study devices and supplies (a Post Office box is not an acceptable address for product shipments). Patients who, in the opinion of the Investigator, are anticipated to be non-compliant with study instructions; Unable to provide or have diminished capacity to provide informed consent; Any condition that an Investigator believes would interfere with the intent of the study or make participation not in the best interest of the patient.