title: With the "universal definition," measurement of creatine kinase-myocardial band rather than troponin allows more accurate diagnosis of periprocedural necrosis and infarction after coronary intervention.
abstract: OBJECTIVE
  We aimed to assess the differential implications of creatine kinase-myocardial band (CK-MB) and troponin measurement with the universal definition of periprocedural injury after percutaneous coronary intervention.
  
  
  BACKGROUND
  Differentiation between definitions of periprocedural necrosis and periprocedural infarction has practical, sociological, and research implications. Troponin is the recommended biomarker, but there has been debate about the recommended diagnostic thresholds.
  
  
  METHODS
  Thirty-two patients undergoing multivessel percutaneous coronary intervention and late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) imaging in a prospective study had cardiac troponin I, CK-MB, and inflammatory markers (C-reactive protein, serum amyloid A, myeloperoxidase, tumor necrosis factor alpha) measured at baseline, 1 h, 6 h, 12 h, and 24 h after the procedure. Three "periprocedural injury" groups were defined with the universal definition: G1: no injury (biomarker <99th percentile); G2: periprocedural necrosis (1 to 3 × 99th percentile); G3: myocardial infarction (MI) type 4a (>3 × 99th percentile). Differences in inflammatory profiles were analyzed.
  
  
  RESULTS
  With CK-MB there were 17, 10, and 5 patients in groups 1, 2, and 3, respectively. Patients with CK-MB-defined MI type 4a closely approximated patients with new CMR-LGE injury. Groups defined with CK-MB showed progressively increasing percentage change in C-reactive protein and serum amyloid A, reflecting increasing inflammatory response (p < 0.05). Using cardiac troponin I resulted in 26 patients defined as MI type 4a, but only a small minority had evidence of abnormality on CMR-LGE, and only 3 patients were defined as necrosis. No differences in inflammatory response were evident when groups were defined with troponin.
  
  
  CONCLUSIONS
  Measuring CK-MB is more clinically relevant for diagnosing MI type 4a, when applying the universal definition. Current troponin thresholds are oversensitive with the arbitrary limit of 3 × 99th percentile failing to discriminate between periprocedural necrosis and MI type 4a. (Myocardial Injury following Coronary Artery bypass Surgery versus Angioplasty: a randomised controlled trial using biochemical markers and cardiovascular magnetic resonance imaging; ISRCTN25699844).
authors.affiliation: Oxford Heart Centre, John Radcliffe Hospital, United Kingdom.
authors.forename: Chris C S
authors.initials: CC
authors.lastname: Lim
authors.forename: William J
authors.initials: WJ
authors.lastname: van Gaal
authors.forename: Luca
authors.initials: L
authors.lastname: Testa
authors.forename: Florim
authors.initials: F
authors.lastname: Cuculi
authors.forename: Jayanth R
authors.initials: JR
authors.lastname: Arnold
authors.forename: Theodoros
authors.initials: T
authors.lastname: Karamitsos
authors.forename: Jane M
authors.initials: JM
authors.lastname: Francis
authors.forename: Steffen E
authors.initials: SE
authors.lastname: Petersen
authors.forename: Janet E
authors.initials: JE
authors.lastname: Digby
authors.forename: Stephen
authors.initials: S
authors.lastname: Westaby
authors.forename: Charalambos
authors.initials: C
authors.lastname: Antoniades
authors.forename: Rajesh K
authors.initials: RK
authors.lastname: Kharbanda
authors.forename: Louise M
authors.initials: LM
authors.lastname: Burrell
authors.forename: Stefan
authors.initials: S
authors.lastname: Neubauer
authors.forename: Adrian P
authors.initials: AP
authors.lastname: Banning
mesh_terms: D000368:Aged; D015906:Angioplasty, Balloon, Coronary / Q000009:adverse effects*; D015415:Biomarkers / Q000097:blood; D052279:Creatine Kinase, MB Form / Q000097:blood*; D016207:Cytokines / Q000097:blood; D005260:Female; D005682:Gadolinium; D006801:Humans; D007249:Inflammation / Q000097:blood; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood* / Q000175:diagnosis / Q000209:etiology; D009206:Myocardium / Q000473:pathology; D009336:Necrosis / Q000175:diagnosis; D012372:ROC Curve; D016032:Randomized Controlled Trials as Topic; D019210:Troponin I / Q000097:blood*
chemical_list: D015415:Biomarkers; D016207:Cytokines; D019210:Troponin I; D005682:Gadolinium; D052279:Creatine Kinase, MB Form