Cardiac CT Calcium Scoring


Cardiac CT Calcium Scoring, Coronary Calcium Score, CT Coronary Calcium

  • Definitions
  1. Coronary Calcium Score
    1. Non-Contrast CT-based quantification of coronary Calcium deposits (Agatson Score)
    2. Score sums the products of attenuation (Hounsfield Units) and area (mm3) of all lesions at coronary arteries
    3. Calcium deposits correlate with atherosclerotic Plaque
  • Indications
  1. CAD Risk stratification of asymptomatic patients
    1. Intermediate risk patients who have not undergone stress testing
    2. Intermediate risk patients with equivocal stress testing
    3. May direct preventive strategies (Aspirin, Statin) with better predictive power than risk factors and serum markers
  • Efficacy
  1. Increased Calcium scoring is an indepedent predictor of CAD event (RR >2.6)
  2. Increased Calcium scoring is associated with an increase in all cause mortality (RR >5.6)
  3. Calcium score does not predict focal stenosis severity
  • Equipment
  1. Electron beam tomography or
  2. Multidetector CT
  • Interpretation
  1. Calcium Score 0: Low risk
  2. Calcium Score 1-100: CAD event Relative Risk = 2.1
  3. Calcium Score 101-400: CAD event Relative Risk = 3.1
    1. Threshold indicating further evaluation with stress testing
  4. Calcium Score 401-1000: CAD event Relative Risk = 4.6
  5. Calcium Score >1000: CAD event Relative Risk = 8.3
  • Adverse Effects
  1. Radiation Exposure: 0.89 mSv (similar to Mammogram)