99th Percentile Upper Reference Limit (URL) for the Meritas Troponin I Test

Inclusion Criteria: 1. Male or female at least 21 years of age at the time of enrollment in the study. 2. Subjects with no medications or no changes in their medications in the last 3 months. 3. Subjects with and without chronic stable morbidities (i.e., renal insufficiency, hypertension, diabetes, hypercholesterolemia, pulmonary disorders, coronary disease, musculoskeletal disorders, etc.). 4. Subjects able to understand and sign the informed consent and the patient questionnaire. Exclusion Criteria: 1. Subjects with a history of heart failure and/or, having received treatment for heart failure. 2. Subject with renal failure. 3. Subjects with a history of unstable heart disease or angina complaints. 4. Subjects with any change in their medication in the last 3 months (diabetics may have small variations in glucose medications but may not have unstable disease, or have suffered a diabetic crisis in the last 6 months). 5. Any known acute infection in the last 30 days. 6. Marathon runners or extreme athletes. 7. Pregnant (self-reported).