Long-Term Effects of Subclinical CAD on Cardiac Function

This study has been completed.
Sponsor:
Information provided by:
National Heart, Lung, and Blood Institute (NHLBI)
ClinicalTrials.gov Identifier:
NCT00006497
First received: November 16, 2000
Last updated: August 20, 2008
Last verified: August 2008
  Purpose

To assess changes in coronary calcium measured by electron beam computed tomography (EBCT) as a predictor of coronary heart disease (CHD) events.


Condition
Cardiovascular Diseases
Coronary Arteriosclerosis
Coronary Disease
Heart Diseases

Study Type: Observational

Resource links provided by NLM:


Further study details as provided by National Heart, Lung, and Blood Institute (NHLBI):

Study Start Date: September 2000
Study Completion Date: August 2008
Primary Completion Date: August 2008 (Final data collection date for primary outcome measure)
Detailed Description:

BACKGROUND:

Despite extensive research over many years, noninvasive methods for detection of the presence and severity of coronary artery disease remain imperfect, in part due to the fact that different, partially interrelated, facets of coronary atherosclerosis may predispose to different manifestations (e.g., luminal diameter narrowing to myocardial ischemia and wall plaque burden to a higher risk or acute thrombosis). One noninvasive index of the degree of coronary atherosclerosis, the extent of coronary artery calcification, has become more accessible to non-invasive evaluation due to the development of fast electron-beam computed tomography (EBCT). Initial studies have shown that EBCT coronary calcification is related to a variety of coronary risk factors and is also predictive to a variable extent in different populations of incident coronary heart disease events, but few data are available concerning the evolution of EBCT-detected coronary calcification and its relation to coronary risk factors or to prevalent or incident coronary heart disease.

The study draws on the success of the Los Angeles South Bay Heart Watch (SBHW) in recruiting an ethnically-diverse sample of individuals at high risk of coronary heart disease events who have undergone serial evaluation by both assessment of conventional coronary heart disease risk factors and by evaluation of coronary arterial calcification by fluoroscopy and by EBCT on sequential evaluations. The study group has been able to maintain contact with the participants and achieve outstanding rates of both contact for follow-up and repeat participation in sequential components of the study.

DESIGN NARRATIVE:

The study follows up 1,000 asymptomatic high-risk survivors from the South Bay Heart Watch population recruited in 1990-1992 (n = 1,461) and studied with EBCT in 1992-1993 (n = 1,309). The primary objective is to examine the effects of baseline risk factors and measures of calcium metabolism on changes in the amount of coronary calcium in this asymptomatic high-risk adult cohort. This observational study has the following specific aims, as follow: 1) relating demographic factors and traditional risk factors to progression in coronary artery calcification (CAC) score over time; 2) relating serum markers of calcium metabolism to changes in CAC score; and 3) relating baseline CAC score and changes in CAC score to left ventricular dysfunction and intervening coronary events.

The SBHW cohort and NHLBI reading center as well as Dr. Azen's data coordinating center are used to examine whether baseline risk factors, ethnic group and indices of calcium metabolism are associated with change in coronary calcium quantity over four to five years. EBCT scans are performed in 1,000 surviving members of the cohort as are repeat measurements of left ventricular hypertrophy, plasma lipids, blood pressure, homocysteine, fibrinogen, para-thyroid hormone and vitamin D levels. The independent relationships between risk factors are examined from the 1994 baseline evaluation and the change in coronary calcium score as determined by EBCT. Logistic regression, which is not dependent on normality of the independent variables, will be used to examine the relation of annualized change in coronary calcium with the incidence of events. The study continues through August, 2008.

  Eligibility

Ages Eligible for Study:   48 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria

No eligibility criteria

  Contacts and Locations
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Please refer to this study by its ClinicalTrials.gov identifier: NCT00006497

Sponsors and Collaborators
Investigators
Investigator: Robert Detrano Harbor-UCLA Research & Education Institute
  More Information

Publications:
ClinicalTrials.gov Identifier: NCT00006497     History of Changes
Other Study ID Numbers: 938
Study First Received: November 16, 2000
Last Updated: August 20, 2008
Health Authority: United States: Federal Government

Additional relevant MeSH terms:
Cardiovascular Diseases
Heart Diseases
Coronary Disease
Coronary Artery Disease
Arteriosclerosis
Atherosclerosis
Myocardial Ischemia
Vascular Diseases
Arterial Occlusive Diseases

ClinicalTrials.gov processed this record on October 19, 2014