title: Clinical implications of microvascular obstruction and intramyocardial haemorrhage in acute myocardial infarction using cardiovascular magnetic resonance imaging.
abstract: OBJECTIVE
  To investigate the clinical implications of microvascular obstruction (MVO) and intramyocardial haemorrhage (IMH) in acute myocardial infarction (AMI).
  
  
  METHODS
  Ninety patients with a first AMI undergoing primary percutaneous coronary intervention (PCI) were studied. T2-weighted, cine and late gadolinium-enhanced cardiovascular magnetic resonance imaging was performed at 5 ± 2 and 103 ± 11 days. Patients were categorised into three groups based on the presence or absence of MVO and IMH.
  
  
  RESULTS
  MVO was observed in 54% and IMH in 43% of patients, and correlated significantly (r = 0.8, p < 0.001). Pre-PCI thrombolysis in myocardial infarction 3 flow was only observed in MVO(-)/IMH(-) patients. Infarct size and impairment of systolic function were largest in MVO(+)/IMH(+) patients (n = 39, 23 ± 9% and 47 ± 7%), smallest in MVO(-)/IMH(-) patients (n = 41, 8 ± 8% and 55 ± 8%) and intermediate in MVO(+)/IMH(-) patients (n = 10, 16 ± 7% and 51 ± 6%, p < 0.001). LVEF increased in all three subgroups at follow-up, but remained intermediate in MVO(+)/IMH(-) and was lowest in MVO(+)/IMH(+) patients. Using random intercept model analysis, only infarct size was an independent predictor for adverse LV remodelling.
  
  
  CONCLUSIONS
  Intramyocardial haemorrhage and microvascular obstruction are strongly related. Pre-PCI TIMI 3 flow is less frequently observed in patients with MVO and IMH. Only infarct size was an independent predictor of LV remodelling.
authors.affiliation: Department of Cardiology, Maastricht University Medical Center, P. Debyelaan 25, PO Box 5800, 6202 AZ Maastricht, The Netherlands. s.bekkers@mumc.nl
authors.forename: Sebastiaan C A M
authors.initials: SC
authors.lastname: Bekkers
authors.forename: Martijn W
authors.initials: MW
authors.lastname: Smulders
authors.forename: Valéria Lima
authors.initials: VL
authors.lastname: Passos
authors.forename: Tim
authors.initials: T
authors.lastname: Leiner
authors.forename: Johannes
authors.initials: J
authors.lastname: Waltenberger
authors.forename: Anton P M
authors.initials: AP
authors.lastname: Gorgels
authors.forename: Simon
authors.initials: S
authors.lastname: Schalla
mesh_terms: D015906:Angioplasty, Balloon, Coronary; D003326:Coronary Circulation; D005260:Female; D006470:Hemorrhage / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008833:Microcirculation; D008875:Middle Aged; D009203:Myocardial Infarction / Q000473:pathology* / Q000503:physiopathology / Q000628:therapy; D015425:Myocardial Reperfusion