Ventricular Size and Value Calcification Measures by Computed Tomography - Ancillary to MESA
Condition: Cardiovascular Diseases; Heart Diseases; Atherosclerosis; Coronary Arteriosclerosis
MeSH terms: Cardiovascular Diseases; Heart Diseases; Atherosclerosis; Arteriosclerosis; Coronary Artery Disease; Myocardial Ischemia
Study type: Observational

Summary: 
      To rescan 6,700 subjects in the MESA study to obtain computed tomography measures of
      calcification.
    

Detailed description: 
      BACKGROUND:

      This study is ancillary to the MultiEthnic Study of Atherosclerosis (MESA) Trial, a
      prospective investigation of the etiology and natural history of atherosclerosis and the
      ability of non-invasive tools to measure atherosclerotic burden and identify high risk
      individuals in a large, population-based cohort. The development of computed tomography (CT)
      to evaluate coronary calcification (CC) now provides a tool to directly measure coronary
      atherosclerosis non-invasively. The information obtained by CT however provides more
      information than CC alone. CT has the ability to measure and quantitate aortic valve
      calcification (AVC), mitral annular calcification (MAC), aortic wall calcification and left
      ventricular size (LVS). The longitudinal nature of this study will allow epidemiologic
      associations to be established for a multitude of risk factors and these measures,
      establishing both the time sequence for each measure and consistency of the association in a
      variety of populations (ethnicity, gender, geographical location and age). Magnetic resonance
      imaging of the heart will also be obtained as part of the MESA trial, and comparisons of LV
      size by CT to magnetic resonance measures will also be performed.

      DESIGN NARRATIVE:

      This study is ancillary to the MultiEthnic Study of Atherosclerosis (MESA) Trial, a
      prospective investigation of the etiology and natural history of atherosclerosis and the
      ability of non-invasive tools to measure atherosclerotic burden and identify high risk
      individuals in a large, population-based cohort. The development of computed tomography (CT)
      to evaluate coronary calcification (CC) now provides a tool to directly measure coronary
      atherosclerosis non-invasively. The information obtained by CT however provides more
      information than CC alone. CT has the ability to measure and quantitate aortic valve
      calcification (AVC), mitral annular calcification (MAC), aortic wall calcification and left
      ventricular size (LVS). The longitudinal nature of this study will allow epidemiologic
      associations to be established for a multitude of risk factors and these measures,
      establishing both the time sequence for each measure and consistency of the association in a
      variety of populations (ethnicity, gender, geographical location and age). Magnetic resonance
      imaging of the heart will also be obtained as part of the MESA trial, and comparisons of LV
      size by CT to magnetic resonance measures will also be performed. The investigators will
      utilize scans already obtained as part of the calcium scanning (at baseline and 3.5 year
      follow-up), and make these four measures on baseline and follow-up scans obtained. The
      additive value of these simple measures to CC score could possibly provide clinicians with
      even more power to identify and stratify the high-risk cardiac patient with both findings.
      This study will also establish the prevalence, in a population based study, of all both AVC
      and MAC, using a technique highly sensitive to see these abnormalities. It has been
      postulated that a 'total atherosclerotic burden' could be obtained by adding CAC to thoracic
      aortic calcification, and this total atherosclerosis score (with or without MAC and AVC)
      might better predict cardiovascular events than CAC alone. Similarly, this cohort of 6,700
      patients with repeat scans can be assessed for factors that enhance or inhibit progression of
      LVS, mitral annular, aortic valve or wall calcification, lending insight into therapies that
      have efficacy against progression of aortic sclerosis or left ventricular enlargement.
    

Observational model: Cohort
Time perspective: Prospective
Sampling method: Probability Sample
Study population: 
        MESA study population - 6814 participants from 6 clinic sites around the US