Cardiac Magnetic Resonance for Asymptomatic Type 2 Diabetics With Cardiovascular High Risk (CATCH) - Pilot Study

Asymptomatic coronary artery disease (CAD) is highly prevalent (ie. 17-59%) in type 2 diabetic patients. In addition, cardiovascular disease remains the most common cause of death in type 2 diabetics. Previous trials using coronary computed tomography angiograms (CCTA) or nuclear myocardial perfusion imaging (MPI) to screen for asymptomatic coronary artery disease requiring intervention have been unsuccessful at reducing cardiovascular and all cause mortality when compared to optimised medical therapy where cardiovascular risk factors are treated in order to reduce cardiovascular complications. Possible reasons for this include, the choice of imaging modality, the intervention chosen (eg. bare metal stents vs drug eluting stents), patient cohort (eg. all diabetics vs high risk diabetics). Stress cardiac magnetic resonance (CMR) is ideally suited to assess this group of high risk patients as there is no radiation exposure and it allows a more complete analysis of the heart including the assessment of myocardial viability, cardiac systolic and diastolic function. The significance of this envisioned randomised controlled trial is firstly to investigate if stress CMR screening will reduce major adverse cardiovascular events including death. Secondly, a study using stress CMR has never been performed.

Inclusion criteria

• Onset of type 2 diabetes at ≥30yrs old with no history of ketoacidosis
• 60-80yrs old
• Framingham Risk Score ≥20%

Exclusion criteria

• Angina pectoris or chest discomfort
• Stress test or coronary angiography within 2 years
• Previous myocardial infarction (MI)
• Previous coronary artery stenting or coronary artery bypass grafting
• Any clinical indication or contraindication for stress testing
• Any contraindication to stress CMR (eg. non-MRI compatible devices)
• Contraindication to gadolinium based contrast agent (eg. Renal impairment with an estimated glomerular filtration rate (GFR) <30ml/min/1.73m2)
• Life expectancy <2 years due to cancer or liver disease
• Contraindication to dual antiplatelet therapy
• Planned need for concomitant cardiac surgery
• Refusal or inability to sign an informed consent.
• Potential for non-compliance towards the requirements in the trial protocol
• Unable to cover the costs of percutaneous coronary intervention (PCI) whether through government subsidies, etc