title: Experimental validation of contrast-enhanced SSFP cine CMR for quantification of myocardium at risk in acute myocardial infarction.
abstract: BACKGROUND
  Accurate assessment of myocardium at risk (MaR) after acute myocardial infarction (AMI) is necessary when assessing myocardial salvage. Contrast-enhanced steady-state free precession (CE-SSFP) is a recently developed cardiovascular magnetic resonance (CMR) method for assessment of MaR up to 1 week after AMI. Our aim was to validate CE-SSFP for determination of MaR in an experimental porcine model using myocardial perfusion single-photon emission computed tomography (MPS) as a reference standard and to test the stability of MaR-quantification over time after injecting gadolinium-based contrast.
  
  
  METHODS
  Eleven pigs were subjected to either 35 or 40 min occlusion of the left anterior descending artery followed by six hours of reperfusion. A technetium-based perfusion tracer was administered intravenously ten minutes before reperfusion. In-vivo and ex-vivo CE-SSFP CMR was performed followed by ex-vivo MPS imaging. MaR was expressed as % of left ventricular mass (LVM).
  
  
  RESULTS
  There was good agreement between MaR by ex-vivo CMR and MaR by MPS (bias: 1 ± 3% LVM, r2= 0.92, p < 0.001), between ex-vivo and in-vivo CMR (bias 0 ± 2% LVM, r2= 0.94, p < 0.001) and between in-vivo CMR and MPS (bias -2 ± 3% LVM, r2= 0.87, p < 0.001. No change in MaR was seen over the first 30 min after contrast injection (p = 0.95).
  
  
  CONCLUSIONS
  Contrast-enhanced SSFP cine CMR can be used to measure MaR, both in vivo and ex vivo, in a porcine model with good accuracy and precision over the first 30 min after contrast injection. This offers the option to use the less complex ex-vivo imaging when determining myocardial salvage in experimental studies.
authors.affiliation: Department of Clinical Physiology, Clinical Sciences, Lund University and Lund University Hospital, Lund, Sweden.
authors.forename: David
authors.identifier: http://orcid.org/0000-0002-6567-8459
authors.initials: D
authors.lastname: Nordlund
authors.affiliation: Department of Clinical Physiology, Clinical Sciences, Lund University and Lund University Hospital, Lund, Sweden.
authors.forename: Mikael
authors.initials: M
authors.lastname: Kanski
authors.affiliation: Department of Clinical Physiology, Clinical Sciences, Lund University and Lund University Hospital, Lund, Sweden.
authors.forename: Robert
authors.initials: R
authors.lastname: Jablonowski
authors.affiliation: Department of Cardiology, Clinical Sciences, Lund University and Lund University Hospital, Lund, Sweden.
authors.forename: Sasha
authors.initials: S
authors.lastname: Koul
authors.affiliation: Department of Cardiology, Clinical Sciences, Lund University and Lund University Hospital, Lund, Sweden.
authors.forename: David
authors.initials: D
authors.lastname: Erlinge
authors.affiliation: Department of Clinical Physiology, Clinical Sciences, Lund University and Lund University Hospital, Lund, Sweden.
authors.forename: Marcus
authors.initials: M
authors.lastname: Carlsson
authors.affiliation: Department of Clinical Physiology, Clinical Sciences, Lund University and Lund University Hospital, Lund, Sweden.
authors.forename: Henrik
authors.initials: H
authors.lastname: Engblom
authors.affiliation: Department of Clinical Physiology, Clinical Sciences, Lund University and Lund University Hospital, Lund, Sweden.|Laboratory of Computing and Medical Informatics, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece.
authors.forename: Anthony H
authors.initials: AH
authors.lastname: Aletras
authors.affiliation: Department of Clinical Physiology, Clinical Sciences, Lund University and Lund University Hospital, Lund, Sweden. hakan.arheden@med.lu.se.
authors.forename: Håkan
authors.initials: H
authors.lastname: Arheden
mesh_terms: D000818:Animals; D003287:Contrast Media / Q000008:administration & dosage*; D004195:Disease Models, Animal; D006571:Heterocyclic Compounds / Q000008:administration & dosage*; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D009203:Myocardial Infarction / Q000000981:diagnostic imaging* / Q000473:pathology; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D009206:Myocardium / Q000473:pathology*; D009942:Organometallic Compounds / Q000008:administration & dosage*; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D018570:Risk Assessment; D012307:Risk Factors; D034421:Sus scrofa; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D003287:Contrast Media; D006571:Heterocyclic Compounds; D009942:Organometallic Compounds; C050823:gadolinium 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetate
keywords: AAR; Area at risk; CE-SSFP; Myocardium at risk