Optimizing Beta Blocker Dosage in Women While Using the Wearable Cardioverter Defibrillator

Inclusion Criteria for Screening Phase: * Female patients with newly diagnosed (never hospitalized for HF in the last 30 days prior to enrollment) ischemic or non-ischemic cardiomyopathy and an EF ≤ 35% at the time of WCD prescription. * Patients prescribed the WCD for an intended 90 ± 14 days of use. * Patients have used the WCD for no more than 14 days from the day of consent. * Patients 18 years of age or older at the time of consent. Inclusion Criteria for Continuation Phase: -After the first 2 weeks of WCD wear, only actively wearing patients averaging at least 105 hours of WCD wear per week (or 15 hours/day) are eligible to continue. Exclusion Criteria for Screening Phase: * Patients with a known contraindication or intolerance to beta-blocker therapy. * Patients with permanent atrial fibrillation. * Patients who have a pacemaker. * Patients with a current or prior implantable cardioverter defibrillator (ICD). * Patients who are self-reporting to be pregnant. * Patients with known congenital or inherited heart disease. * Patients participating in another interventional clinical trial. * Patients not expected to live longer than 3 months. Exclusion Criteria for Continuation Phase: -Patients ending WCD use within the first two weeks of use.