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A Pilot Study Comparing the Programmed Delay Between the Atrial and Ventricle Interval (BRAVO-CRT)

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ClinicalTrials.gov Identifier: NCT00794183
Recruitment Status : Terminated (funding difficulty)
First Posted : November 19, 2008
Last Update Posted : June 26, 2012
Sponsor:
Collaborator:
Information provided by (Responsible Party):

Study Description
Brief Summary:

The idea of this study is to compare different ways of setting up a pacemaker, using blood tests to give us information about how well it's working. We hope to learn if we can use this approach to figure out the best pacemaker setup ("programming") for each individual patient.

The setting we propose to adjust is the timing between the impulse sent between top and bottom chambers.


Condition or disease Intervention/treatment Phase
Heart Failure Device: CRT device settings Early Phase 1

Detailed Description:

There are different kinds of pacemakers and different ways they can be set up to try to make the heart beat regularly. A normal heart has four chambers; these four chambers pump in a co-ordinated way to move blood effectively. When pacemakers were first invented, they told the heart when to pump, but didn't make the four chambers work well together. Newer pacemakers can give more detailed instructions, so the chambers work together more effectively. We already know that the newer (bi-ventricular) pacemakers work better for some patients with heart failure.

There are blood tests (often referred to as "markers") that give us information about how well your heart is working and about how your body is responding to heart failure. The idea of this study is to compare different ways of setting up a pacemaker, using these blood tests to give us information about how well it's working. We hope to learn if we can use this approach to figure out the best pacemaker setup ("programming") for each individual patient.

Usually pacemakers have two wires or leads, one is in the top right chamber and the other in the bottom right chamber of the heart. The newer pacemakers, which are given to patients with heart failure, have an additional lead or wire, which goes to the left side of the heart. So when heart contracts the lead from top chamber sends impulses to bottom chambers and the leads in right and left sides of bottom chamber responds by sending impulses in a co-ordinated way enabling heart to contract efficiently.

Currently, the standard way of treating patients with heart failure is by pacing the top and then bottom chambers, based on a timing interval determined by ultrasound, while also pacing the two bottom chambers in a coordinated manner. There are differences of opinion among experts and by previous studies regarding this method. Pacing is accomplished through pacemaker wires, which are placed in the right top chamber, the right bottom chamber and the left bottom chamber of the heart.

The setting we propose to adjust is the timing between the impulse sent between top and bottom chambers.


Study Design

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 25 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single (Participant)
Primary Purpose: Treatment
Official Title: A Pilot Study of theRelationship Between Atrio-Ventricular Delay and Changes in Biochemical Markers of Chronic Heart Failure During Cardiac Resynchronization Therapy (BRAVO-CRT)
Study Start Date : June 2004
Primary Completion Date : May 2010
Study Completion Date : November 2010

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Heart Failure
U.S. FDA Resources

Arms and Interventions

Arm Intervention/treatment
Active Comparator: 1
AVD set by taking the larger of 0.50ms or A-V interval 0.30
Device: CRT device settings
Comparision of A-V delay settings
Active Comparator: 2
AVD set by taking the larger of 0.50ms or A-V interval 0.50
Device: CRT device settings
Comparision of A-V delay settings
Active Comparator: 3
AVD set by taking the larger of 0.50ms or A-V interval 0.70
Device: CRT device settings
Comparision of A-V delay settings


Outcome Measures

Primary Outcome Measures :
  1. To assess the effect of CRT atrioventricular delay settings on biochemical markers in blood through 6 months [ Time Frame: end of the study ]

Secondary Outcome Measures :
  1. assess effects of echocardiogram through 6months after CRT on heart failure [ Time Frame: end to study ]
  2. assess the effects of minnesota Living with heart failure questionaire through 6 months after CRT on heart failure [ Time Frame: end of study ]
  3. assess effects of six minute hall walk through 6 months after CRt on heart failure [ Time Frame: end of study ]
  4. assess effects of SDANN through 6 months after CRT on heart failure [ Time Frame: end of study ]

Eligibility Criteria

Information from the National Library of Medicine

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

Inclusion Criteria:

  • Diagnosis of chronic heart failure
  • patients on stable pharmacologic therapy for at least 3 months
  • EF< 35%
  • age >18 years
  • NYHA functional class III or IV
  • eligible for either CRT pacer or CRT defibrillator for heart failure
  • Ischemic or non-ischemic cardiomyopathy
  • patients that are able to tolerate VDD mode with a lower rate of 40bpm programming

Exclusion Criteria:

  • systolic blood pressure <70mmHg
  • Likely to receive a left ventricular assist device or cardiac transplant within 6 months of implant procedure
  • patients who have previously received a CRT device
  • documented atrial fibrillation
  • complete heart block
Contacts and Locations

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00794183


Locations
United States, Minnesota
University of Minnesota
Minneapolis, Minnesota, United States, 55455
Sponsors and Collaborators
University of Minnesota - Clinical and Translational Science Institute
Minnesota Medical Foundation
Investigators
Principal Investigator: David G Benditt, MD University of Minnesota - Clinical and Translational Science Institute
More Information

Responsible Party: University of Minnesota - Clinical and Translational Science Institute
ClinicalTrials.gov Identifier: NCT00794183     History of Changes
Other Study ID Numbers: 0303M44604
First Posted: November 19, 2008    Key Record Dates
Last Update Posted: June 26, 2012
Last Verified: June 2012

Keywords provided by University of Minnesota - Clinical and Translational Science Institute:
heart failure
CRT
CHF

Additional relevant MeSH terms:
Heart Failure
Heart Diseases
Cardiovascular Diseases