Ontario Multidetector Computed Tomographic (MDCT) Coronary Angiography Study (OMCAS)

• Descriptive statistics (rates and proportions) will be calculated for the number of "avoidable" diagnostic cardiac catheterizations. [ Time Frame: After both MDCTCA and CICA are completed ] [ Designated as safety issue: No ]
• The accuracy of MDCTCA to CICA will be compared in categorizing patients inot single, double, triple vessel, left main disease or no coronary stenosis. [ Time Frame: After both MDCTCA and CICA are completed ] [ Designated as safety issue: No ]
• The accuracy of MDCTCA to eliminate correctly the need for CICA will be calculated. [ Time Frame: After both MDCTCA and CICA are completed ] [ Designated as safety issue: No ]

Multidetector Computed Tomographic Coronary Angiography (MDCTCA) has been recently demonstrated to be accurate and may be used as a potential alternative to conventional invasive coronary angiography, which requires cardiac catheterization, for the diagnosis of coronary artery disease. The purpose of this study is to see if MDCTCA can identify significant coronary artery disease as good as or better than conventional coronary angiography (CICA). The study is designed to enroll 900 subjects and is being conducted in 6 hospitals in Ontario. Subjects scheduled for conventional cardiac catheterization and coronary angiography will receive an additional test using MDCTCA. The information gathered during the MDCTCA will be compared to the results of the scheduled conventional invasive coronary angiogram.

• Coronary Arteriosclerosis
• Cardiomyopathies
• Heart Defects, Congenital
• Heart Valve Diseases

Inclusion Criteria:

Group 1

• Valvular heart disease (mitral stenosis, mitral regurgitation, aortic stenosis or aortic insufficiency) or
• Congenital heart disease (i.e. VSD, ASD, PDA) or
• Cardiomyopathy OR

Group 2

• Intermediate probability of coronary artery disease (probability of 10-90%) after clinical evaluation and traditional non-invasive testing

Exclusion Criteria:

• Age < 18 years
• Lack of consent
• Renal Insufficiency (GFR < 60 mL/min)
• Allergy to contrast agent
• Refractory angina requiring urgent/emergent coronary angiography (as per treating physician)
• Pregnancy or breast feeding
• Uncontrolled heart rate
• Previous CABG or PCI/Stent
• Chronic atrial fibrillation
• History of acute myocardial infarction, as defined by a creatine kinase (CK) level greater than 2 times normal with a troponin level above 4.
• Unable to perform 20 second breath-hold