Reducing Decompensation Events Utilizing Intracardiac Pressures in Patients With Chronic Heart Failure (HF) (REDUCEhf) (REDUCEhf)

Inclusion Criteria: Subjects with heart failure that only sometimes interferes with daily activities (New York Heart Association [NYHA] Class II (1)) or subjects with heart failure which severely limits daily activities (NYHA Class III (2)) at baseline Subject has appropriate medical therapy for heart failure (such as diuretic, angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) and beta blocker) for at least three months prior to the baseline evaluation. Subject has been on stable medications maximized to the subject's tolerance of ACE or ARB and beta blockers as determined by the study investigator for at least 30 days prior to baseline evaluation. (Stable is defined as no more than a 100% increase or a 50% decrease in dose.) If a subject is intolerant of ACE, ARB or beta blockers documented evidence must be available. Subject has had at least one heart failure-related hospitalization or at least one heart failure-related emergency department or urgent care visit necessitating heart failure-related intravenous therapy (e.g. diuretic administration) within 12 months prior to the baseline evaluation To be considered for Chronicle ICD: Subject has, or is at risk of having, a heart beat that is too fast and his/her doctor has determined he/she needs an implantable cardioverter defibrillator (ICD). Class II Subjects with cardiac disease resulting in slight limitation of physical activity. They are comfortable at rest. Ordinary physical activity results in fatigue, palpitation, dyspnea, or angina. Class III Subjects with cardiac disease resulting in marked limitation of physical activity. They are comfortable at rest. Less than ordinary activity causes fatigue, palpitation, dyspnea, or angina. Exclusion Criteria: Subjects with severe heart failure who should always be resting (NYHA Class IV(3)) or Stage D(4) refractory heart failure. Subjects with severe renal dysfunction. Subjects with severe non-cardiac condition limiting 12-month survival. Subjects in concurrent studies that may confound the results. (3)Class IV Subjects with cardiac disease resulting in inability to carry on any physical activity without discomfort. Symptoms of heart failure or the anginal syndrome may be present even at rest. If any physical activity is undertaken, discomfort is increased. (4)Stage D refractory heart failure: Patients who have marked symptoms at rest despite maximal medical therapy (e.g., those who are recurrently hospitalized or cannot be safely discharged from the hospital without specialized interventions)