title: Microvascular perfusion 1 week and 6 months after myocardial infarction by first-pass perfusion cardiovascular magnetic resonance imaging.
abstract: OBJECTIVE
  To characterise the evolution of myocardial perfusion during the first 6 months after myocardial infarction by first-pass perfusion cardiovascular magnetic resonance imaging (CMR) and determine its significance.
  
  
  METHODS
  Prospective cohort design.
  
  
  METHODS
  Single-centre study in a teaching hospital in Spain.
  
  
  METHODS
  40 patients with a first ST-elevation myocardial infarction, single-vessel disease and thrombolysis in myocardial infarction (TIMI) grade 3 flow (stent in 33 patients) underwent rest and low-dose dobutamine CMR 7 (SD 1) and 184 (SD 11) days after infarction. Microvascular perfusion was assessed at rest by visual assessment and quantitative analysis of first-pass perfusion CMR. Of the 640 segments, 290 segments subtended by the infarct-related artery (IRA) were focused on.
  
  
  RESULTS
  Both 1 week and 6 months after infarction, segments with normal perfusion showed more wall thickening, contractile reserve and wall thickness, and less transmural necrosis, p <0.05 in all cases. Of 76 hypoperfused segments at the first week, 47 (62%) normalised perfusion at the sixth month. However, 42 segments (14% of the whole group) showed chronic abnormal perfusion; these segments showed worse CMR indices in the late phase (p<0.05 in all cases).
  
  
  CONCLUSIONS
  In patients with an open IRA, more than half of the segments with abnormal perfusion at the first week are normally perfused after six months. First-pass perfusion CMR shows that in a small percentage of segments, abnormal perfusion may become a chronic phenomenon-these areas have a more severe deterioration of systolic function, wall thickness, contractile reserve and the transmural extent of necrosis.
authors.affiliation: Department of Cardiology, Hospital Clínico y Universitario de Valencia, Universidad de Valencia, Valencia, Spain. vicentbodi@hotmail.com
authors.forename: V
authors.initials: V
authors.lastname: Bodí
authors.forename: J
authors.initials: J
authors.lastname: Sanchis
authors.forename: M P
authors.initials: MP
authors.lastname: López-Lereu
authors.forename: J
authors.initials: J
authors.lastname: Núñez
authors.forename: R
authors.initials: R
authors.lastname: Sanz
authors.forename: P
authors.initials: P
authors.lastname: Palau
authors.forename: C
authors.initials: C
authors.lastname: Gómez
authors.forename: D
authors.initials: D
authors.lastname: Moratal
authors.forename: F J
authors.initials: FJ
authors.lastname: Chorro
authors.forename: A
authors.initials: A
authors.lastname: Llácer
mesh_terms: D015331:Cohort Studies; D003326:Coronary Circulation / Q000502:physiology*; D003971:Diastole; D005260:Female; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008833:Microcirculation / Q000502:physiology; D008875:Middle Aged; D009203:Myocardial Infarction / Q000473:pathology / Q000503:physiopathology*; D009206:Myocardium / Q000473:pathology; D009336:Necrosis; D011446:Prospective Studies; D013599:Systole