Multiple Cardiac Sensors for the Management of Heart Failure

Inclusion Criteria:

1. Subject is age 18 or above, or of legal age to give informed consent
2. Implanted with an cardiac resynchronization therapy defibrillator (CRT-D) orimplantable cardioverter-defibrillator (ICD) device that has HeartLogic
3. Current symptomatic heart failure or New York Heart Association Class II or III at thetime of enrollment
4. Remotely monitored by LATITUDE 5.0 (or future versions)
5. Willing and capable of participating in all study visits and complying withmedication/treatment requirements associated with this clinical study at an approvedclinical study center.
6. Meet at least one of the three following conditions:

• At least one documented hospitalization with a primary diagnosis of worsening forheart failure during the 12 months prior to enrollment; or
• Unscheduled outpatient visit with IV diuretic therapy for acute worsening of HFduring 90 days prior to enrollment; or
• N-terminal-pro brain natriuretic peptide (NT-proBNP) greater than 600 pg/mL orbrain natriuretic peptide (BNP) greater than 150 pg/mL at any time during 90 daysprior to enrollment

Exclusion Criteria:

1. The subject is unable to sign or refuses to sign the patient informed consent
2. Symptomatic heart failure at rest or New York Heart Association Class IV at the timeof enrollment
3. The subject is implanted with unipolar right atrial or right ventricular leads
4. Subject has received or is scheduled to receive a heart transplant or ventricularassist device within the next 6 months
5. Subject is pregnant or planning to become pregnant during the study
6. Subject is enrolled in any other concurrent study (without prior written approval fromBoston Scientific, excluding registries)
7. Glomerular filtration rate <25 mL/min who are non-responsive to diuretic therapy orare on chronic renal dialysis
8. Regularly scheduled intravenous heart failure therapy (for example inotropes ordiuretics)
9. A life expectancy of less than 12 months per clinician discretion
10. APPLICABLE TO PHASE II ONLY: Subject enrolled in Phase I of MANAGE-HF
11. APPLICABLE TO PHASE II ONLY: Subject has been managed with HeartLogic Alerts ON atanytime within the past 6 months.