title: The role of cardiovascular magnetic resonance in patients presenting with chest pain, raised troponin, and unobstructed coronary arteries.
abstract: OBJECTIVE
  Troponin measurement is used in the assessment and risk stratification of patients presenting acutely with chest pain when the main cause of elevation is coronary artery disease. However, some patients have no coronary obstruction on angiography, leading to diagnostic uncertainty. We evaluated the incremental diagnostic value of cardiovascular magnetic resonance (CMR) in these patients.
  
  
  RESULTS
  Sixty consecutive patients (mean age 44 years, 72% male) with a troponin-positive episode of chest pain and unobstructed coronary arteries were recruited within 3 months of initial presentation. All patients underwent CMR with cine imaging, T2-weighted imaging for detection of inflammation, and late gadolinium enhancement imaging for detection of infarction/fibrosis. An identifiable basis for troponin elevation was established in 65% of patients. The commonest underlying cause was myocarditis (50%), followed by myocardial infarction (11.6%) and cardiomyopathy (3.4%). In the 35% of patients where no clear diagnosis was identified by CMR, significant myocardial infarction/fibrosis was excluded.
  
  
  CONCLUSIONS
  CMR is a valuable adjunct to conventional investigations in a diagnostically challenging and important group of patients with troponin-positive chest pain and unobstructed coronary arteries.
authors.affiliation: Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London SW3 6NP, UK.
authors.forename: Ravi G
authors.initials: RG
authors.lastname: Assomull
authors.forename: Jonathan C
authors.initials: JC
authors.lastname: Lyne
authors.forename: Niall
authors.initials: N
authors.lastname: Keenan
authors.forename: Ankur
authors.initials: A
authors.lastname: Gulati
authors.forename: Nicholas H
authors.initials: NH
authors.lastname: Bunce
authors.forename: Simon W
authors.initials: SW
authors.lastname: Davies
authors.forename: Dudley J
authors.initials: DJ
authors.lastname: Pennell
authors.forename: Sanjay K
authors.initials: SK
authors.lastname: Prasad
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D002311:Cardiomyopathy, Dilated / Q000150:complications / Q000175:diagnosis; D002637:Chest Pain / Q000209:etiology*; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D006331:Heart Diseases / Q000150:complications / Q000175:diagnosis*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008131:London; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications; D009205:Myocarditis / Q000150:complications / Q000175:diagnosis; D011446:Prospective Studies; D054549:Takotsubo Cardiomyopathy / Q000150:complications / Q000175:diagnosis; D014336:Troponin / Q000097:blood
chemical_list: D015415:Biomarkers; D003287:Contrast Media; D014336:Troponin; D019786:Gadolinium DTPA