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Long-Term Results of DDD Pacing in Obstructive Hypertrophic Cardiomyopathy
This study has been completed.
First Received: November 3, 1999   Last Updated: March 3, 2008   History of Changes
Sponsor: National Heart, Lung, and Blood Institute (NHLBI)
Information provided by: National Institutes of Health Clinical Center (CC)
ClinicalTrials.gov Identifier: NCT00001530
  Purpose

DDD pacing improves symptoms and relieves LV outflow tract (LVOT) obstruction in most patients with hypertrophic cardiomyopathy (HCM). Notably, when pacing is temporarily discontinued, the beneficial effects of pacing are evident in sinus rhythm. The long term results of this novel therapy are, however, uncertain. We propose (1) to record the hemodynamic changes following >4 years of pacing; and (2) to determine whether DDD pacing continues to be necessary in patients who have had a substantial relief of their LVOT obstruction. Patients who have had >50% reduction in LVOT pressure gradients will be randomized to two pacing modalities: DDD at 70 beats per minute and AAI pacing at 70 beats per minute (DDD switched off), and reevaluated after a six-month period.


Condition
Cardiomyopathy, Hypertrophic

Study Type: Observational
Official Title: Long-Term Results of DDD Pacing in Obstructive Hypertrophic Cardiomyopathy

Resource links provided by NLM:


Further study details as provided by National Institutes of Health Clinical Center (CC):

Estimated Enrollment: 120
Study Start Date: April 1996
Estimated Study Completion Date: May 2000
Detailed Description:

DDD pacing improves symptoms and relieves LV outflow tract (LVOT) obstruction in most patients with hypertrophic cardiomyopathy (HCM). Notably, when pacing is temporarily discontinued, the beneficial effects of pacing are evident in sinus rhythm. The long term results of this novel therapy are, however, uncertain. We propose (1) to record the hemodynamic changes following >4 years of pacing; and (2) to determine whether DDD pacing continues to be necessary in patients who have had a substantial relief of their LVOT obstruction. Patients who have had >50% reduction in LVOT pressure gradients will be randomized to two pacing modalities: DDD at 70 beats per minute and AAI pacing at 70 beats per minute (DDD switched off), and reevaluated after a six-month period.

  Eligibility

Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria

Group 1:

HCM patients, aged grater than 20 years of either gender who received DDD pacemakers at the NIH at least 4 years ago, for relief of LVOT obstruction and drug-refractory symptoms.

Group 2:

HCM patients selected from Group 1 who at the follow-up cardiac catheterization are demonstrated to have either (1) no significant LVOT obstruction (less than 30mm HG at rest and less than 50mm HG with Isuprel); or (2) a substantial reduction of the LVOT obstruction (greater than 50% reduction in LVOT gradient).

Patient who have developed a heart block will be excluded from group 2.

Females must have a negative pregnancy test.

  Contacts and Locations
Please refer to this study by its ClinicalTrials.gov identifier: NCT00001530

Locations
United States, Maryland
National Heart, Lung and Blood Institute (NHLBI)
Bethesda, Maryland, United States, 20892
Sponsors and Collaborators
  More Information

Publications:
Study ID Numbers: 960059, 96-H-0059
Study First Received: November 3, 1999
Last Updated: March 3, 2008
ClinicalTrials.gov Identifier: NCT00001530     History of Changes
Health Authority: United States: Federal Government

Keywords provided by National Institutes of Health Clinical Center (CC):
Cardiac Hypertrophy
Drug-Refractory
Hemodynamic Benefits
Obstruction
Pacemaker Therapy
Hypertrophic Cardiomyopathy

Additional relevant MeSH terms:
Pathological Conditions, Anatomical
Hypertrophy
Aortic Stenosis, Subvalvular
Heart Diseases
Cardiomyopathy, Hypertrophic
Cardiovascular Diseases
Aortic Valve Stenosis
Cardiomyopathies
Heart Valve Diseases

ClinicalTrials.gov processed this record on November 09, 2009