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

This study has been terminated.
(funding difficulty)
Sponsor:
Collaborator:
Minnesota Medical Foundation
Information provided by (Responsible Party):
University of Minnesota - Clinical and Translational Science Institute
ClinicalTrials.gov Identifier:
NCT00794183
First received: November 18, 2008
Last updated: June 22, 2012
Last verified: June 2012
  Purpose

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 Intervention Phase
Heart Failure
Device: CRT device settings
Phase 0

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Single Blind (Subject)
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)

Resource links provided by NLM:


Further study details as provided by University of Minnesota - Clinical and Translational Science Institute:

Primary Outcome Measures:
  • To assess the effect of CRT atrioventricular delay settings on biochemical markers in blood through 6 months [ Time Frame: end of the study ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • assess effects of echocardiogram through 6months after CRT on heart failure [ Time Frame: end to study ] [ Designated as safety issue: No ]
  • assess the effects of minnesota Living with heart failure questionaire through 6 months after CRT on heart failure [ Time Frame: end of study ] [ Designated as safety issue: No ]
  • assess effects of six minute hall walk through 6 months after CRt on heart failure [ Time Frame: end of study ] [ Designated as safety issue: No ]
  • assess effects of SDANN through 6 months after CRT on heart failure [ Time Frame: end of study ] [ Designated as safety issue: No ]

Enrollment: 25
Study Start Date: June 2004
Study Completion Date: November 2010
Primary Completion Date: May 2010 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
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

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.

  Eligibility

Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Both
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
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 ClinicalTrials.gov identifier: 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

No publications provided

Responsible Party: University of Minnesota - Clinical and Translational Science Institute
ClinicalTrials.gov Identifier: NCT00794183     History of Changes
Other Study ID Numbers: 0303M44604
Study First Received: November 18, 2008
Last Updated: June 22, 2012
Health Authority: United States: Institutional Review Board

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

ClinicalTrials.gov processed this record on July 28, 2014