The goal of the PREEMPT-HF study is to collect device and clinical event data to evaluate extended applications of the HeartLogic Heart Failure Diagnostic (HeartLogic) in a broad spectrum of heart failure patients with an implantable cardioverter defibrillator or cardiac resynchronization therapy defibrillator. There are no primary safety and/or efficacy endpoints for this study.

Heart failure is a complex clinical syndrome with high morbidity, mortality, and economic burden. Chronic Heart Failure is persistent, gradually progressive, and punctuated by episodes of acute worsening leading to hospitalizations. Therefore, there remains an unmet clinical need to slow the progression of Heart Failure and prevent hospitalizations. HeartLogic, available in Boston Scientific cardiac resynchronization therapy devices and defibrillators, combines novel sensor parameters such as heart sounds and respiration with other measurements like thoracic impedance, heart rate, and activity into a HeartLogic Index for the early detection of worsening Heart Failure. However, there is limited data on the association of HeartLogic with the risk of Hear Failure readmissions and tachyarrhythmias, or for phenotyping the broad spectrum of Heart Failure patients.

Subjects will be followed for approximately 12 months after the baseline visit to collect the required number of clinical events to support the study objectives. These events are called Reviewable Clinical Events, and include all-cause hospitalizations and Heart Failure outpatient visits.

Clinical event definitions are as follows:

• Hospitalization (all-cause): the subject is admitted to inpatient hospital care and discharged on a different calendar date.
• Heart Failure Hospitalization: the subject is admitted with signs/symptoms of congestive heart failure and receives unscheduled augmented Heart Failure therapy with oral or intravenous medications, ultrafiltration therapy or other parenteral therapy.
• Heart Failure Readmission (30-day): the subject is admitted for an unplanned hospitalization for any cause within 30 days post discharge from a Heart Failure hospitalization.
• Heart Failure Outpatient Visit: the subject has signs/symptoms of Congestive Heart Failure, and receives unscheduled intravenous decongestive therapy (e.g., Intravenous diuretics, Intravenous inotropes, Intravenous vasoactive drugs, ultrafiltration) in a setting that does not involve a hospitalization (e.g., emergency room, Heart Failure clinic, primary care clinic, etc.).

Inclusion Criteria:

• Subject is age 18 or above, or of legal age to give informed consent specific to each country and national laws.
• Subject has a documented diagnosis of heart failure.
• Subject has a Boston Scientific Cardiac Resynchronization Therapy Defibrillator or Implantable Cardioverter Defibrillator device implant that has HeartLogic, with Heart Failure Sensors turned ON, Respiratory Sensor turned ON, and Sleep Incline Sensor turned ON.
• Subject has an active bipolar right ventricle lead implant.
• Subject is enrolled in LATITUDE (NXT 5.0 or future version), and is willing to be remotely monitored from the baseline visit for approximately 12 months with HeartLogic disabled.

Exclusion Criteria:

• Subject has received or is scheduled to receive a heart transplant or ventricular assist device (VAD).
• Subject is enrolled in any concurrent clinical study without prior Boston Scientific written approval (excluding registries).
• Subject has a life expectancy of less than 12 months.
• Subject has a history of non-compliance to medical care or known inability to comply with requirements of the clinical study protocol

Patients with Heart Failure implanted with Boston Scientific Cardiac Resynchronization Therapy Defibrillator or Implantable Cardioverter Defibrillator using HeartLogic