Diagnostic and prognostic implications of coronary artery calcification detected by computed tomography
- Thomas C Gerber, MD, PhD, FACC, FAHA
Thomas C Gerber, MD, PhD, FACC, FAHA
- Professor of Medicine and Radiology
- College of Medicine, Mayo Clinic
- Christopher M Kramer, MD, FACC, FAHA
Christopher M Kramer, MD, FACC, FAHA
- Ruth C. Heede Professor of Cardiology
- Professor of Radiology
- University of Virginia Health System
- Section Editors
- Warren J Manning, MD
Warren J Manning, MD
- Section Editor — Noninvasive Cardiac Imaging and Stress Testing
- Professor of Medicine and Radiology
- Harvard Medical School
- Bernard J Gersh, MB, ChB, DPhil, FRCP, MACC
Bernard J Gersh, MB, ChB, DPhil, FRCP, MACC
- Editor-in-Chief — Cardiovascular Medicine
- Section Editor — Coronary Heart Disease; Myopericardial Disease
- Professor of Medicine
- Mayo Clinic College of Medicine
- Deputy Editors
- Brian C Downey, MD, FACC
Brian C Downey, MD, FACC
- Deputy Editor — Cardiology
- Assistant Professor of Medicine
- Tufts University School of Medicine
- Susanna I Lee, MD, PhD
Susanna I Lee, MD, PhD
- Deputy Editor — Radiology
- Associate Professor of Radiology
- Harvard Medical School
- Massachusetts General Hospital
The association between vascular calcification and vascular disease has been known to anatomists and pathologists for several hundred years. Radiologic detection of coronary artery calcification (CAC) in vivo by fluoroscopy was described in the late 1950s , and an association between the presence of CAC and the risk of cardiovascular events was subsequently demonstrated .
This topic will review the diagnostic and prognostic use of CAC. Coronary computed tomography angiography (CCTA) is discussed separately. (See "Noninvasive coronary imaging with cardiac computed tomography and cardiovascular magnetic resonance".)
CT scanner types — The development of electron beam computed tomographic scanning (EBCT) in the early 1980s permitted noninvasive and quantitative detection of CAC for the first time. The most widely used and best-established measure of CAC for assessment of the diagnostic and prognostic value of EBCT CAC scanning is the Agatston score . Other measures, such as the volume score and calcium mass have been less well studied.
Since 1999, the temporal resolution of multidetector row or multislice CT scanners (MDCT or MSCT) has improved sufficiently to permit imaging of the beating heart with no or little motion artifact. The early studies examining the diagnostic and prognostic value of CAC scanning that are discussed below have been conducted with EBCT. However, EBCT is now essentially obsolete. 64-detector MDCT is considered state-of-the-art and most newer studies of CAC have been performed with this technology. One study demonstrated that CAC scores using both volume score and Agatston score were equivalent between EBT and 64-detector MDCT .
The software used to analyze CAC has been shown to generate some variability. However, intra- and inter-scan agreement of CAC measured on the same MDCT scanner is quite high . Methods for measuring CAC from contrast-enhanced CT angiograms have been proposed . However, non-contrast scans remain the standard for making these measurements.
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- COMPUTED TOMOGRAPHY
- CT scanner types
- CAC scanning
- Radiation exposure
- CAC AND CORONARY ARTERY STENOSIS
- CAC scoring
- Importance of ethnicity
- CAC AND MYOCARDIAL ISCHEMIA
- EMERGENCY DEPARTMENT EVALUATION OF CHEST PAIN
- CAC AND PROGNOSIS IN ASYMPTOMATIC PATIENTS
- General predictive value
- Added value to Framingham risk score
- - Identifying high-risk individuals
- - Role in moderate risk patients
- - Effect on prognosis
- Role in the elderly
- Comparison to hsCRP and other biomarkers
- Added value in smokers
- Serial measurements
- - CAC progression and risk
- Comparison with carotid intima-media thickness
- CAC AND PROGNOSIS IN SYMPTOMATIC PATIENTS
- POSSIBLE EFFECT OF TREATMENT IN ASYMPTOMATIC PATIENTS
- Observational studies
- Randomized trials
- EFFECTS ON COMPLIANCE AND RESOURCE UTILIZATION
- Resource utilization
- USE OF CAC SCORING
- SUMMARY AND RECOMMENDATIONS