title: Intracoronary microparticles and microvascular obstruction in patients with ST elevation myocardial infarction undergoing primary percutaneous intervention.
abstract: OBJECTIVE
  Microparticles (MP) are cell-derived fragments known to be increased in the blood of patients with acute coronary syndromes. We aimed to assess, in ST elevation myocardial infarction (STEMI), the systemic and local (in the culprit coronary artery) levels of platelet-derived MP (PMP, CD42+CD31+) and endothelial-derived MP (EMP, CD42-CD31+) and their relation to indexes of microvascular obstruction (MVO).
  
  
  RESULTS
  In 78 STEMI patients undergoing successful primary percutaneous coronary intervention, blood samples were sequentially drawn from the aorta and the culprit coronary artery for cytofluorimetric MP detection. Thrombolysis in myocardial infarction (TIMI) flow, thrombus score (TS), corrected TIMI frame count (cTFC), myocardial blush grade (MBG), quantitative blush evaluator (QuBE) score, and 90 min ST resolution (ΣSTR) were calculated. Both PMP and EMP levels were significantly higher in the intracoronary than in the aortic blood samples. Intracoronary PMP and EMP levels were positively related to TS and cTFC and inversely related to MBG and QuBE. Aortic PMP (but not EMP) levels were related to TS and cTFC and, inversely, to QuBE. Intracoronary PMP were independently related to angiographic and electrocardiographic MVO in a multivariate model.
  
  
  CONCLUSIONS
  The correlations of intracoronary EMP and of both systemic and intracoronary PMP levels with TS support the role of MP as markers of ongoing thrombosis. Moreover, the correlation of intracoronary MP with indexes of microvascular dysfunction suggests, for the first time, a possible direct role of MP in the pathogenesis of MVO.
authors.affiliation: Department of Cardiovascular Medicine, Catholic University of the Sacred Heart, L.go A. Gemelli, 8, 00168 Rome, Italy. italo.porto@gmail.com
authors.forename: Italo
authors.initials: I
authors.lastname: Porto
authors.forename: Luigi Marzio
authors.initials: LM
authors.lastname: Biasucci
authors.forename: Giovanni Luigi
authors.initials: GL
authors.lastname: De Maria
authors.forename: Antonio Maria
authors.initials: AM
authors.lastname: Leone
authors.forename: Giampaolo
authors.initials: G
authors.lastname: Niccoli
authors.forename: Francesco
authors.initials: F
authors.lastname: Burzotta
authors.forename: Carlo
authors.initials: C
authors.lastname: Trani
authors.forename: Alessandra
authors.initials: A
authors.lastname: Tritarelli
authors.forename: Rocco
authors.initials: R
authors.lastname: Vergallo
authors.forename: Giovanna
authors.initials: G
authors.lastname: Liuzzo
authors.forename: Filippo
authors.initials: F
authors.lastname: Crea
mesh_terms: D000704:Analysis of Variance; D001792:Blood Platelets / Q000473:pathology*; D055252:Cell-Derived Microparticles / Q000473:pathology*; D054059:Coronary Occlusion / Q000473:pathology; D003328:Coronary Thrombosis / Q000473:pathology; D004730:Endothelium, Vascular / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D008833:Microcirculation / Q000502:physiology; D055806:Microvessels; D008875:Middle Aged; D015999:Multivariate Analysis; D009203:Myocardial Infarction / Q000473:pathology* / Q000628:therapy; D015425:Myocardial Reperfusion; D062645:Percutaneous Coronary Intervention; D011446:Prospective Studies