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Response to Cardiac Resynchronization Therapy of Previously Right Ventricular Paced Heart Failure Patients

This study has been completed.
Boston Scientific Corporation
Information provided by (Responsible Party):
Allina Health System Identifier:
First received: November 2, 2011
Last updated: February 23, 2016
Last verified: February 2016
The present proposal is designed to investigate the response to CRT in patients who were previously paced from the right ventricle (RV). The negative physiologic and structural changes associated with chronic RV pacing are well documented, but patient response following upgrade to CRT after chronic RV pacing has not been well characterized in a large cohort.

Heart Failure
Pacing Induced Dyssynchrony

Study Type: Observational
Study Design: Time Perspective: Retrospective
Official Title: Response to Cardiac Resynchronization Therapy of Previously Right Ventricular Paced Heart Failure Patients

Resource links provided by NLM:

Further study details as provided by Allina Health System:

Primary Outcome Measures:
  • Death from any cause [ Time Frame: Average of 4 years ]
    Retrospectively measure the time in days from device implant to death, if applicable.

  • Cardiovascular Hospitalization [ Time Frame: Average of 4 years ]
    Retrospectively measure the time in days from device implant to hospitalization, if applicable.

Secondary Outcome Measures:
  • Change in ejection fraction [ Time Frame: Approximately one year ]
    A measure of cardiac performance.

Enrollment: 743
Study Start Date: October 2011
Study Completion Date: June 2014
Primary Completion Date: June 2014 (Final data collection date for primary outcome measure)
Previously RV Paced
Patients who were RV paced prior to receiving a cardiac resynchronization therapy device.
Non-Previously RV Paced
Patients who received a CRT device without being previously RV paced.

Detailed Description:

The RV apex has historically been used as the site for ventricular pacing in cases of sinus node dysfunction or atrioventricular block because of its relatively accessible location for lead implantation. Initial studies showed RV pacing improved symptoms, exercise capacity, quality of life, and survival in these patients.11-13 However, more recent studies have illustrated that chronic RV pacing may actually impair LV systolic function and increase the risks of heart failure, hospitalization, and death in some patients.

The primary hypothesis is that patients upgraded to CRT from a RV pacemaker respond better than those receiving CRT as a first time device. To test this hypothesis the investigators will compare changes in cardiac size and function, and hospitalization and survival rates between the two patient groups.

The second hypothesis will investigate whether changes in septal dyssynchrony are correlated with changes in ejection fraction in previously RV paced patients. The investigators believe that the patients with the most improvement in septal dyssynchrony due to RV pacing will see the greatest improvement in LV function following upgrade to CRT. A significant correlation between change in IM-S and change in EF will support the hypothesis.


Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population
A retrospective review of patients receiving CRT at United Heart & Vascular Clinic between 2003 and 2009.

Inclusion Criteria:

  • Received a CRT device between 2003 and 2009 at United Heart & Vascular Clinic
  • QRS duration > 120 msec
  • Pre-CRT ejection fraction =< 35%

Exclusion Criteria:

  Contacts and Locations
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Please refer to this study by its identifier: NCT01466621

United States, Minnesota
United Heart & Vascular Clinic
St. Paul, Minnesota, United States, 55102
Sponsors and Collaborators
Allina Health System
Boston Scientific Corporation
Principal Investigator: Alan J Bank, MD United Heart & Vascular Clinic
  More Information

Responsible Party: Allina Health System Identifier: NCT01466621     History of Changes
Other Study ID Numbers: ISRCRM110009(Boston Sci Corp)
Study First Received: November 2, 2011
Last Updated: February 23, 2016

Keywords provided by Allina Health System:
cardiac resynchronization therapy
heart failure

Additional relevant MeSH terms:
Heart Failure
Heart Diseases
Cardiovascular Diseases processed this record on April 28, 2017