title: Microvascular dysfunction following ST-elevation myocardial infarction and its recovery over time.
abstract: OBJECTIVE
  It is unclear whether microvascular dysfunction following ST-elevation myocardial infarction (STEMI) is prognostic for long-term left ventricular function (LVF), and whether recovery of the microvasculature status is associated with LVF improvement. The aim of this study was to assess whether microvascular dysfunction in the infarct-related artery (IRA), as assessed by coronary flow reserve (CFR) within one week after PPCI, was associated with LVF at both four months and two years.
  
  
  RESULTS
  In 62 patients, CFR and hyperaemic microvascular resistance index (HMRI) in the IRA were assessed by intracoronary Doppler flow measurements within one week and at four months. CMR was performed at the same time points and also at two years. CFR at baseline was associated with left ventricular ejection fraction (LVEF) at four months (β=4.66, SE=2.10; p=0.03) and at two-year follow-up (β=5.84, SE=2.45; p=0.02). HMRI was not associated with LVF. In large infarcts, absolute improvement of CFR in the first four months was associated with LVEF improvement (β=5.09, SE=1.86, p=0.01).
  
  
  CONCLUSIONS
  Microvascular dysfunction, assessed by CFR, in the subacute phase of STEMI is prognostic for LVEF at four months and two years. This underlines the pivotal role of microvascular dysfunction following STEMI.
authors.affiliation: Department of Cardiology, Academic Medical Center, Amsterdam, the Netherlands.
authors.forename: Mariëlla E C J
authors.initials: MECJ
authors.lastname: Hassell
authors.forename: Matthijs
authors.initials: M
authors.lastname: Bax
authors.forename: Martijn A
authors.initials: MA
authors.lastname: van Lavieren
authors.forename: Robin
authors.initials: R
authors.lastname: Nijveldt
authors.forename: Alexander
authors.initials: A
authors.lastname: Hirsch
authors.forename: Lourens
authors.initials: L
authors.lastname: Robbers
authors.forename: Koen M
authors.initials: KM
authors.lastname: Marques
authors.forename: Jan G P
authors.initials: JGP
authors.lastname: Tijssen
authors.forename: Felix
authors.initials: F
authors.lastname: Zijlstra
authors.forename: Albert C
authors.initials: AC
authors.lastname: van Rossum
authors.forename: Ronak
authors.initials: R
authors.lastname: Delewi
authors.forename: Jan J
authors.initials: JJ
authors.lastname: Piek
mesh_terms: D000368:Aged; D015906:Angioplasty, Balloon, Coronary / Q000379:methods; D003326:Coronary Circulation / Q000502:physiology; D015150:Echocardiography, Doppler / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D000072657:ST Elevation Myocardial Infarction / Q000150:complications* / Q000503:physiopathology*; D018487:Ventricular Dysfunction, Left / Q000150:complications* / Q000503:physiopathology*; D016277:Ventricular Function, Left / Q000502:physiology*