title: Diagnostic contribution of cardiac magnetic resonance in patients with acute coronary syndrome and culprit-free angiograms.
abstract: BACKGROUND
  In spite of robust knowledge about underlying ischemic myocardial damage, acute coronary syndromes (ACS) with culprit-free angiograms raise diagnostic concerns. The present study aimed to evaluate the additional value of cardiac magnetic resonance (CMR) over commonly available non-CMR standard tests, for the differentiation of myocardial injury in patients with ACS and non-obstructed coronary arteries.
  
  
  METHODS
  Patients with ACS, elevated hs-TnT, and a culprit-free angiogram were prospectively enrolled into the study between January 2009 and July 2013. After initial evaluation with standard tests (ECG, echocardiography, hs-TnT) and provisional exclusion of acute myocardial infarction (AMI) in coronary angiogram, patients were referred for CMR with the suspicion of myocarditis or Takotsubo cardiomyopathy (TTC). According to the result of CMR, patients were reclassified as having myocarditis, AMI, TTC, or non-injured myocardium as assessed by late gadolinium enhancement.
  
  
  RESULTS
  Out of 5110 patients admitted with ACS, 75 had normal coronary angiograms and entered the study; 69 of them (92%) were suspected for myocarditis and 6 (8%) for TTC. After CMR, 49 patients were finally diagnosed with myocarditis (65%), 3 with TTC (4%), 7 with AMI (9%), and 16 (21%) with non-injured myocardium. The provisional diagnosis was changed or excluded in 23 patients (31%), with a 9% rate of unrecognized AMI.
  
  
  CONCLUSIONS
  The study results suggest that the evaluation of patients with ACS and culprit-free angiogram should be complemented by a CMR examination, if available, because the initial work-up with non-CMR tests leads to a significant proportion of misdiagnosed AMI.
authors.affiliation: 2nd Department of Cardiology, Silesian Medical University, Zabrze, Poland.
authors.forename: Damian
authors.initials: D
authors.lastname: Kawecki
authors.affiliation: 2nd Department of Cardiology, Silesian Medical University, Zabrze, Poland.
authors.forename: Beata
authors.initials: B
authors.lastname: Morawiec
authors.affiliation: Center of Cardiac Magnetic Resonance, University Hospital, Lausanne, Switzerland.
authors.forename: Pierre
authors.initials: P
authors.lastname: Monney
authors.affiliation: Department of Cardiology, University Hospital, Lausanne, Switzerland.
authors.forename: Cyril
authors.initials: C
authors.lastname: Pellaton
authors.affiliation: 2nd Department of Cardiology, Silesian Medical University, Zabrze, Poland.
authors.forename: Celina
authors.initials: C
authors.lastname: Wojciechowska
authors.affiliation: 2nd Department of Cardiology, Silesian Medical University, Zabrze, Poland.
authors.forename: Joanna
authors.initials: J
authors.lastname: Jojko
authors.affiliation: Department of Internal Medicine and Clinical Pharmacology, Silesian Medical University, Katowice, Poland.
authors.forename: Marcin
authors.initials: M
authors.lastname: Basiak
authors.affiliation: 2nd Department of Cardiology, Silesian Medical University, Zabrze, Poland.
authors.forename: Brygida
authors.initials: B
authors.lastname: Przywara-Chowaniec
authors.affiliation: Department of Cardiology, University Hospital, Lausanne, Switzerland.
authors.forename: Stephane
authors.initials: S
authors.lastname: Fournier
authors.affiliation: 2nd Department of Cardiology, Silesian Medical University, Zabrze, Poland.
authors.forename: Ewa
authors.initials: E
authors.lastname: Nowalany-Kozielska
authors.affiliation: Center of Cardiac Magnetic Resonance, University Hospital, Lausanne, Switzerland.
authors.forename: Juerg
authors.initials: J
authors.lastname: Schwitter
authors.affiliation: Department of Cardiology, University Hospital, Lausanne, Switzerland.
authors.forename: Olivier
authors.initials: O
authors.lastname: Muller
mesh_terms: D054058:Acute Coronary Syndrome / Q000175:diagnosis* / Q000473:pathology*; D000328:Adult; D002309:Cardiology / Q000379:methods; D002454:Cell Differentiation; D017023:Coronary Angiography / Q000379:methods*; D003331:Coronary Vessels / Q000473:pathology; D004562:Electrocardiography / Q000379:methods; D005260:Female; D005682:Gadolinium / Q000737:chemistry; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009205:Myocarditis / Q000175:diagnosis / Q000473:pathology; D009206:Myocardium / Q000473:pathology; D011446:Prospective Studies; D054549:Takotsubo Cardiomyopathy / Q000175:diagnosis / Q000473:pathology; D016896:Treatment Outcome; D014336:Troponin / Q000378:metabolism; D055815:Young Adult
chemical_list: D014336:Troponin; D005682:Gadolinium