A considerable proportion of patients with clinically suspected coronary artery disease (CAD) do not have angiographic signs of luminal narrowing caused by coronary atherosclerosis. In patients with suspected CAD, we will assess the ability of cardiovascular biomarkers to identify patients with (a) angiographically normal epicardial coronary vessels (b) absence of significant epicardial coronary stenosis, as assessed by coronary computed tomography angiography (CCTA). Patients will be stratified according to the presence or absence of dynamic changes of high sensitivity cardiac troponin T levels above the 99th percentile.

This is an observational study of patients with suspected coronary artery disease referred to coronary computed tomography angiography (CCTA). The plan is to include 1000 patients prior to CCTA at two centers.

Blood samples for biomarker measurement will be obtained prior to the procedures. The diagnostic results of the imaging tests will be compared to the levels of circulating troponins. Patient will be followed for a minimum of 12 months and the incidence of cardiovascular death, all-cause mortality, acute coronary syndromes, revascularization, heart failure, stroke and cardiac arrhythmias requiring rehospitalization. Symptoms of angina pectoris according to the Canadian Cardiovascular Society grading of angina pectoris and symptoms of chronic heart failure according to the New York Heart Association classification of chronic heart failure will be recorded.

Inclusion Criteria:

• Consenting patient over the age of 18 referred to CCTA for suspected coronary artery disease

Exclusion Criteria:

• Inability to provide informed consent.
• Short life expectancy (<12 months) due to non-cardiovascular disease

This is an observational study of patients with suspected coronary artery disease referred to either emergent or out-patient coronary computed tomography angiography (CCTA)