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Effects Rapid Atrial Pacing Has on the Electrocardiogram (ECG) in Patients With Dual Chamber Pacemakers

This study has been completed.
National Institutes of Health (NIH)
Wake Forest University Health Sciences
Information provided by (Responsible Party):
Dawood Darbar, Vanderbilt University Identifier:
First received: April 16, 2009
Last updated: December 9, 2014
Last verified: December 2014
The purpose of this study is to learn what effect rapid atrial pacing (in patients with dual chamber pacemakers) will have on the electrocardiogram including the QT Interval. The investigators are also interested in the differences caused by genes.

Prolonged QT Interval

Study Type: Observational
Study Design: Observational Model: Cohort
Time Perspective: Prospective
Official Title: Modulation of QT Interval by Rapid Atrial Pacing in Patients With Dual Chamber Pacemakers

Resource links provided by NLM:

Further study details as provided by Vanderbilt University:

Primary Outcome Measures:
  • Determine the effect of abrupt changes in atrial rate on QT intervals [ Time Frame: 7 days ]

Enrollment: 12
Study Start Date: April 2009
Study Completion Date: June 2012
Primary Completion Date: June 2012 (Final data collection date for primary outcome measure)
Detailed Description:

This study requires a total of two study days as well as two follow up visits. During study day one, baseline blood will be drawn, a baseline electrocardiogram will be performed, and continuous QT Interval monitoring will be performed. The pacemaker rate will be increased to 90bpm at different time intervals and additional blood will be drawn to measure the effects of these rates changes.

On study day two, baseline blood will be drawn, a urine specimen will be obtained, an electrocardiogram will be performed, and continuous QT Interval monitoring will be performed. Following the acquisition of this information, the pacemaker rate will be decreased to 80bpm. We will obtain blood specimens, a urine specimen and an electrocardiogram at 30 minutes post rate change and again at 60 minutes post rate change.

Two days following the rate decrease to 80bpm, the patient will return to clinic to have their rate decreased to 70bpm. In two more days, the patient will return for a final rate change to 60bpm.


Ages Eligible for Study:   21 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Probability Sample
Study Population
Cardiology Clinic

Inclusion Criteria:

  • Must be at least 21 years old
  • Must have a dual chamber pacemaker implanted more than three months ago
  • Must be followed by the Vanderbilt University Medical Center's Arrhythmia Device Clinic
  • The indication for the pacemaker must not be related to coronary artery disease (CAD) or congestive heart failure (CHF)

Exclusion Criteria:

  • Cannot be pacemaker dependent
  • History of ventricular arrhythmias and/or implantable defibrillators (ICDs)
  • History of paroxysmal, persistent, or permanent atrial fibrillation (AF)
  • Congenital long QT syndrome
  • History of coronary artery disease
  • History of, or currently receiving, treatment for congestive heart failure
  • Unable to tolerate dual-chamber pacing (DDD) at 90 bpm due to palpitations, chest pain, shortness of breath, lightheadedness, dizziness, or presyncope
  • Pregnant women
  • Any patient without specific documentation of an echocardiogram negative for CHF (systolic or diastolic dysfunction)within five years prior to study enrollment
  • Any patient without specific documentation of an objective diagnostic test to rule out CAD within five years prior to study enrollment
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Please refer to this study by its identifier: NCT00883610

United States, Tennessee
Vanderbilt University Medical Center
Nashville, Tennessee, United States, 37232-8802
Sponsors and Collaborators
Vanderbilt University
National Institutes of Health (NIH)
Wake Forest University Health Sciences
Principal Investigator: Dawood Darbar, M.D., Ph.D., F.A.C.C. Vanderbilt University Medical Center
  More Information

Responsible Party: Dawood Darbar, Associate Professor of Medicine and Clinical Pharmacology, Vanderbilt University Identifier: NCT00883610     History of Changes
Other Study ID Numbers: 070070
Study First Received: April 16, 2009
Last Updated: December 9, 2014

Keywords provided by Vanderbilt University:
QT Interval
Dual Chamber Pacemaker
Atrial Fibrillation

Additional relevant MeSH terms:
Long QT Syndrome
Arrhythmias, Cardiac
Heart Diseases
Cardiovascular Diseases
Heart Defects, Congenital
Cardiovascular Abnormalities
Congenital Abnormalities
Pathologic Processes processed this record on May 25, 2017