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Cardiac Resynchronization Therapy Defibrillator Based Impedance Monitoring Study

This study has been completed.
Information provided by (Responsible Party):
St. Jude Medical Identifier:
First received: July 11, 2007
Last updated: May 18, 2016
Last verified: May 2016
The intent of this feasibility study is to collect and analyze intra-thoracic impedance measurements from a CRT-D device in a heart failure population.

Condition Intervention Phase
Heart Failure Device: Transthoracic Impedance Phase 2

Study Type: Interventional
Study Design: Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Diagnostic
Official Title: CRT-D Based Impedance Monitoring Feasibility Study

Resource links provided by NLM:

Further study details as provided by St. Jude Medical:

Primary Outcome Measures:
  • To assess the use of the impedance feature in conjunction with other functions of the CRT-D device [ Time Frame: 6 months ]

Enrollment: 75
Study Start Date: July 2007
Study Completion Date: August 2008
Primary Completion Date: August 2008 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: 1
Transthoracic impedance device implanted.
Device: Transthoracic Impedance
Impedance measures will be automatically collected via the device

Detailed Description:

This is a multi-center feasibility study intended to collect information on changes in intra-thoracic impedance measurements from CRT-D devices. In order to obtain an intra-thoracic impedance measurement, the device delivers a subthreshold impulse that measures the resistance between two electrodes.

At the programmed interval, measurements will be obtained between six different lead configurations.


Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

Eligible patients will meet all of the following:

  1. 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
  2. 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
  3. 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
  4. 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:

  1. Be less than 18 years of age
  2. Have had a recent myocardial infarction, unstable angina or cardiac revascularization within 40 days of enrollment
  3. Have had a recent Cerebrovascular Accident or Transient Ischemic Attack within three months of enrollment
  4. Have a contraindication for an emergency thoracotomy
  5. Have an indication that requires programming device in atrial pacing mode
  6. Have permanent (chronic) atrial fibrillation
  7. Have a capped or inactive right atrial or right ventricular pacing/defibrillator lead
  8. Have a hypersensitivity to a single 1.0mg dose of dexamethasone sodium phosphate or short term contact with heparin
  9. Be pregnant or planning a pregnancy in the next 6-months
  10. Be currently participating in a clinical investigation that includes an active treatment arm
  11. Have a life expectancy of less than six months due to any condition
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT00500838

United States, Arkansas
Baptist Health Medical Center
Little Rock, Arkansas, United States, 72205
United States, California
Glendale Memorial Hospital
Glendale, California, United States, 91204
United States, New Jersey
Deborah Heart and Lung
Browns Mills, New Jersey, United States, 08015
United States, South Carolina
Medical University of South Carolina
Charleston, South Carolina, United States, 29401
Sponsors and Collaborators
St. Jude Medical
Principal Investigator: G. Stephen Greer, MD Baptist Health
  More Information

Responsible Party: St. Jude Medical Identifier: NCT00500838     History of Changes
Other Study ID Numbers: 40004384
Study First Received: July 11, 2007
Last Updated: May 18, 2016

Keywords provided by St. Jude Medical:
Cardiac Resynchronization Therapy
Transthoracic Impedance

Additional relevant MeSH terms:
Heart Failure
Heart Diseases
Cardiovascular Diseases processed this record on September 21, 2017