title: Comparison between visual grading and planimetric quantification of microvascular obstruction extent assessment in reperfused acute myocardial infarction.
abstract: OBJECTIVE
  Current methods for infarct size and microvascular obstruction (MVO) quantification by cardiac magnetic resonance (CMR) imaging rely on planimetry. This method is time-consuming. We sought to evaluate a direct assessment of MVO severity based on visual evaluation and to compare it to a reference method.
  
  
  METHODS
  CMR was performed in 112 consecutive patients after reperfused myocardial infarction. MVO was estimated by direct visual assessment based on a three-grade severity scale (MVO 1, mild; MVO 2, moderate; MVO 3, severe) on late gadolinium-enhancement (LGE).
  
  
  RESULTS
  MVO was present in 69 patients (61.6 %). Quantitative MVO extent significantly increased accordingly to visual MVO grading (p < 0.01). Correlation between visual grading and quantitative assessment was excellent (r = 0.92, IQR 0.88-0.95, p < 0.001). CMR inter- and intraobserver variability for visual MVO evaluation was low (κ = 0.93 and κ = 0.96, respectively), whereas quantitative MVO assessment suffered from moderate agreement (interobserver, bias = -0.81 ± 1.8 g LV; intraobserver, -0.83 ± 2.1 g LV). Visual evaluation was significantly faster than reference method (0.65 ± 0.37 vs. 10.2 ± 2.9 min, p < 0.0001).
  
  
  CONCLUSIONS
  MVO severity based on direct visual assessment on LGE images is feasible, rapid, reproducible and agrees very well with quantitative methods, with a very low inter- and intraobserver variability. Our approach could be used for routine evaluation in patients undergoing CMR after acute myocardial infarction.
  
  
  CONCLUSIONS
  • Microvascular obstruction direct visual evaluation is feasible, rapid and highly reproducible. • Microvascular obstruction direct visual evaluation correlates well with quantification by planimetry. • Microvascular obstruction or no-reflow phenomenon is determined on late gadolinium-enhanced images. • Cardiac MRI is useful for myocardial damage assessment after myocardial infarction.
authors.affiliation: Université Paris-Saclay, Université Paris-Sud, UVSQ, CESP, INSERM UMR 1018 ; EpReC Team Assistance Publique - Hôpitaux de Paris, Imagerie Cardiaque et Vasculaire interventionnelle, Hôpital Ambroise Paré, 9 avenue du Général De Gaulle, 92104, Boulogne-Billancourt, France. marc.sirol@gmail.com.
authors.forename: Marc
authors.initials: M
authors.lastname: Sirol
authors.affiliation: Université Paris-Saclay, Université Paris-Sud, UVSQ, CESP, INSERM UMR 1018 ; EpReC Team Assistance Publique - Hôpitaux de Paris, Imagerie Cardiaque et Vasculaire interventionnelle, Hôpital Ambroise Paré, 9 avenue du Général De Gaulle, 92104, Boulogne-Billancourt, France.
authors.forename: Heger
authors.initials: H
authors.lastname: Gzara
authors.affiliation: Department of Anesthesiology and Critical Care Medicine and Clinical Epidemiology and Biostatistics, Lariboisière University Hospital, Paris, France.
authors.forename: Etienne
authors.initials: E
authors.lastname: Gayat
authors.affiliation: Université Paris-Diderot, Sorbonne Paris Cité, 10 Avenue de Verdun, 75010, Paris, France.
authors.forename: Raphael
authors.initials: R
authors.lastname: Dautry
authors.affiliation: Cardiology Department, CHU de Poitiers, Poitiers, France.
authors.forename: Barnabas
authors.initials: B
authors.lastname: Gellen
authors.affiliation: Service de Cardiologie, Hôpital Lariboisière, Assistance Publique-Hôpitaux de Paris, INSERM U942, Université Paris Diderot, Paris, France.
authors.forename: Damien
authors.initials: D
authors.lastname: Logeart
authors.affiliation: Université Paris-Diderot, Sorbonne Paris Cité, 10 Avenue de Verdun, 75010, Paris, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Soyer
authors.affiliation: Unité de Recherche Clinique, Saint Louis - Lariboisière - Fernand Widal University Hospital, AP-HP, Paris, France.
authors.forename: Eric
authors.initials: E
authors.lastname: Vicaut
authors.affiliation: AP-HP; Université Paris Diderot, Sorbonne Paris Cité, Paris, France.|UMR-S 1180, INSERM, Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France.
authors.forename: Jean-Jacques
authors.initials: JJ
authors.lastname: Mercadier
mesh_terms: D001157:Arterial Occlusive Diseases / Q000000981:diagnostic imaging; D003287:Contrast Media; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging*; D005260:Female; D005682:Gadolinium; D006801:Humans; D008279:Magnetic Resonance Imaging; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D055806:Microvessels / Q000000981:diagnostic imaging*; D008875:Middle Aged; D009203:Myocardial Infarction / Q000000981:diagnostic imaging* / Q000628:therapy; D015425:Myocardial Reperfusion / Q000379:methods; D062645:Percutaneous Coronary Intervention; D011446:Prospective Studies; D000072657:ST Elevation Myocardial Infarction / Q000000981:diagnostic imaging* / Q000628:therapy; D017131:Thrombectomy; D015912:Thrombolytic Therapy
chemical_list: D003287:Contrast Media; D005682:Gadolinium
keywords: Magnetic resonance imaging; Myocardial infarction; Myocardial reperfusion; Myocardial reperfusion injury; No-reflow phenomenon