title: Reperfusion ventricular arrhythmia bursts identify larger infarct size in spite of optimal epicardial and microvascular reperfusion using cardiac magnetic resonance imaging.
abstract: OBJECTIVE
  Ventricular arrhythmia (VA) bursts following recanalisation in acute ST-elevation myocardial infarction (STEMI) are related to larger infarct size (IS). Inadequate microvascular reperfusion, as determined by microvascular obstruction (MVO) using cardiac magnetic resonance imaging (CMR), is also known to be associated with larger IS. This study aimed to test the hypothesis that VA bursts identify larger infarct size in spite of optimal microvascular reperfusion.
  
  
  METHODS
  All 65 STEMI patients from the Maastricht ST elevation (MAST) study with brisk epicardial flow (TIMI 3), complete ST recovery post-percutaneous coronary intervention and early CMR were included. Using 24-hour Holter registrations from the time of admission, VA bursts were identified against subject-specific Holter background VA rates using a statistical outlier method. MVO and final IS were determined using delayed enhancement CMR.
  
  
  RESULTS
  MVO was present in 37/65 (57%) of patients. IS was significantly smaller in the group without MVO (median 9.4% vs. 20.5%; p < 0.001). IS in the group with MVO did not differ depending on VA burst ( n = 28/37; median 20.8% vs. 19.7%; p = 0.64). However, in the group without MVO, VA burst was associated with significantly larger IS ( n = 17/28; median 10.5% vs. 4.1%; p = 0.037). In multivariable analyses, VA burst as well as anterior infarct location remained independent predictors of larger infarct size.
  
  
  CONCLUSIONS
  In the presence of suboptimal reperfusion with MVO by CMR, VA burst does not further define MI size. However, with optimal TIMI 3 reperfusion and optimal microvascular perfusion (i.e. no MVO), VA burst is associated with larger IS, indicating that VA burst is a marker of additional cell death.
authors.affiliation: 1 Maastricht University Medical Center, Maastricht, The Netherlands.|2 Duke University Medical Center and Duke Clinical Research Institute, Durham, NC, USA.
authors.forename: Kirian
authors.initials: K
authors.lastname: van der Weg
authors.affiliation: 3 Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Wichert J
authors.initials: WJ
authors.lastname: Kuijt
authors.affiliation: 1 Maastricht University Medical Center, Maastricht, The Netherlands.
authors.forename: Sebastiaan Cam
authors.initials: SC
authors.lastname: Bekkers
authors.affiliation: 3 Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Jan Gp
authors.initials: JG
authors.lastname: Tijssen
authors.affiliation: 2 Duke University Medical Center and Duke Clinical Research Institute, Durham, NC, USA.
authors.forename: Cynthia L
authors.initials: CL
authors.lastname: Green
authors.affiliation: 1 Maastricht University Medical Center, Maastricht, The Netherlands.
authors.forename: Miguel E
authors.initials: ME
authors.lastname: Lemmert
authors.affiliation: 2 Duke University Medical Center and Duke Clinical Research Institute, Durham, NC, USA.
authors.forename: Mitchell W
authors.initials: MW
authors.lastname: Krucoff
authors.affiliation: 1 Maastricht University Medical Center, Maastricht, The Netherlands.
authors.forename: Anton Pm
authors.initials: AP
authors.lastname: Gorgels
mesh_terms: D003326:Coronary Circulation / Q000502:physiology*; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D008833:Microcirculation / Q000502:physiology; D008875:Middle Aged; D015425:Myocardial Reperfusion / Q000009:adverse effects*; D009206:Myocardium / Q000473:pathology*; D010496:Pericardium / Q000473:pathology* / Q000503:physiopathology; D012189:Retrospective Studies; D000072657:ST Elevation Myocardial Infarction / Q000150:complications / Q000175:diagnosis* / Q000601:surgery; D012720:Severity of Illness Index; D017180:Tachycardia, Ventricular / Q000175:diagnosis* / Q000209:etiology
keywords: Myocardial infarction; arrhythmias; electrocardiography; magnetic resonance imaging; microvascular obstruction; myocardial reperfusion injury