Early Cardiac Magnetic Resonance Imaging in Suspected Non-ST-Elevation Myocardial Infarction

Background and rationale: Evaluating patients with acute chest pain, elevated high-sensitive cardiac troponin (hs-cTn) levels and non-diagnostic electrocardiogram (ECG), i.e. suspected non-ST elevation myocardial infarction (MI), is a daily challenge. Although contemporary hs-cTn assay-based algorithms have greatly facilitated clinical decision-making, still one-quarter of patients is categorized as 'observe' group and in whom a diagnosis initially remains unknown. Although routinely treated as acute (MI) with referral to invasive coronary angiography (ICA), up to one-third does not have obstructive coronary artery disease (CAD). Follow-up cardiac magnetic resonance imaging (CMR) has been shown to be a very useful diagnostic tool in this setting but is not part of routine clinical care in every patient. Objectives: To investigate in patients with suspected non-ST elevation MI meeting the 'observe' criteria and who are scheduled for ICA: 1) the prevalence of coronary artery disease as well as non-coronary artery disease related and extra-cardiac diseases by adding CMR early in the diagnostic pathway, and 2) the number of major adverse cardiac events (MACE) and a composite of MACE and major (non-cardiac) adverse events after 30 days and one year. These objectives allow an accurate estimate of the number of potentially avoidable ICA in the future and whether early CMR could be a safe gatekeeper for inappropriate ICA. Study population and design: In this prospective, observational two-center study in The Netherlands (MUMC+ and VieCuri Medical Center), 87 consecutive patients with acute chest pain, non-diagnostic ECG and hs-cTn levels meeting the observe criteria and scheduled for ICA, will be investigated. Patients will undergo a comprehensive CMR examination prior to ICA and will be followed-up at one month and one year. After completion of follow-up, an independent clinical diagnosis committee will adjudicate a final diagnosis: at discharge and after one year. The f