Cardiac Resynchronization Therapy Defibrillator Based Impedance Monitoring Study

Inclusion Criteria:

Eligible patients will meet all of the following:

Have an approved indication per American College of Cardiology/American Heart Association/Heart Rhythm Society guidelines for implantation of a Cardiac Resynchronization Therapy Defibrillator (CRT-D) or have a previously implanted St. Jude Medical (SJM) CRT-D system capable of enabling the diagnostic impedance monitoring feature with implant occurring within the last 14 days
Have had at least one hospitalization, emergency department visit, or clinic visit within the past 12 months for treatment of decompensated heart failure requiring intravenous diuretics, intravenous inotropes, Natrecor (Nesiritide) therapy, or an increase in an oral diuretic of ≥100% over a 24 hour period
Have the ability to maintain a patient diary for recording daily weights, symptoms related to heart failure, changes in diuretic therapy, and any unscheduled clinic or hospital visits
Have the ability to provide informed consent for study participation and be willing and able to comply with the prescribed follow-up tests and schedule of evaluation

Exclusion Criteria:

Patients will be excluded if they meet any of the following:

Be less than 18 years of age
Have had a recent myocardial infarction, unstable angina or cardiac revascularization within 40 days of enrollment
Have had a recent Cerebrovascular Accident or Transient Ischemic Attack within three months of enrollment
Have a contraindication for an emergency thoracotomy
Have an indication that requires programming device in atrial pacing mode
Have permanent (chronic) atrial fibrillation
Have a capped or inactive right atrial or right ventricular pacing/defibrillator lead
Have a hypersensitivity to a single 1.0mg dose of dexamethasone sodium phosphate or short term contact with heparin
Be pregnant or planning a pregnancy in the next 6-months
Be currently participating in a clinical investigation that includes an active treatment arm
Have a life expectancy of less than six months due to any condition