To evaluate intravascular attenuation of the coronary arteries and image quality in an individualized scan and CM injection protocol whereas both scan and injection parameters are tailored to the individual patient in a North American, European and Asian patient population.

To evaluate the radiation dose and contrast media dose of this individualized approach for CCTA in an American, European and Chinese patient population.

To evaluate the injection parameters required for an average American, European and Chinese patient population.

Inclusion Criteria:

• To be eligible for the study: (All answers must be "YES" for subject to be eligible.)

  1. Referred for a clinically indicated CCTA scan.
  2. Patient aged older than 18.
  3. Subject must provide written informed consent prior to any study-related procedures being performed.
  4. Subject must be willing to comply with all clinical study procedures.
  5. Atypical or typical complaints of angina.
  6. No previous cardiovascular history.
  7. Possibility of 'flash' mode scan; patient heart rate below 70 beats per minute and regular rhythm.

Exclusion Criteria:

• The presence of the following excludes subjects from the study: (All answers must be "NO" for subject to be eligible.)

  1. Contraindications for CT coronary angiography, including:

     1. Inability to perform a breath hold for at least the expected scan time
     2. Unstable angina
     3. Hemodynamic instability
     4. Known history of CAD
     5. Pregnancy
     6. Renal insufficiency (defined as Creatinine <1.5 mg/dL or GFR<30 mL/min)
     7. Iodine allergy

  2. Insufficient cannula venous access (preferred 18G, minimal 20G cannula)

  3. Subject has an acute psychiatric disorder.

  4. Subject is unwilling to comply with the requirements of the protocol.

  5. Subject has previously entered this study.

Adults with complaints of angina, referred for a clinically indicated CCTA scan