This study examines the relationship between the SCOUT DM device and coronary artery calcification as determined by rapid computed tomography in patients at risk for coronary heart disease.

This is a cross-sectional, single site, cohort screening trial. The correlation between the measured skin fluorescence and the CACS will be determined using a design that includes stratification by gender, subject age and subject CAC score. This design requires a single patient visit to the clinical site and a single measurement on the SCOUT device.

Inclusion Criteria:

• Males ≥ 45 years or females ≥ 50 years old that have had a coronary artery calcification score determined by rapid computed tomography at the clinical site within the last six months.

Exclusion Criteria:

• Receiving investigational treatments
• Psychosocial issues that interfere with an ability to follow study procedures
• Known to be pregnant
• Receiving dialysis or having known renal compromise
• Scars, tattoos, rashes or other disruption/discoloration on the left volar forearm.
• Recent or current oral steroid therapy or topical steroids applied to the left forearm
• Current chemotherapy, or chemotherapy within the past 12 months
• Receiving medications that fluoresce*
• Known to have, or at risk for, photosensitivity reactions ( e.g., sensitive to ultraviolet light, or taking medication known to cause photosensitivity)

Subjects are sorted into the follwoing categories for age (years): men:45-54,55-64,65+, women: 50-59, 60-69, 70+. In addition, subjects will be sorted into the follwoing categories for CACS:0-10, 11-100, 101-400, 401-1000, >1000 and absence/presence of diagnosed diabetes (type 1 or type 2)