Myocardial edema as detected by pre-contrast T1 and T2 MRI delineates area at risk associated with acute myocardial infarction

Details

• Alternative Title:
  JACC Cardiovasc Imaging
• Personal Author:
  Ugander, Martin ; Bagi, Paul S. ; Oki, Abiola J. ; Chen, Billy ; Hsu, Li-Yueh ; Aletras, Anthony H. ; Shah, Saurabh ; Greiser, Andreas ; Kellman, Peter ; Arai, Andrew E.
• Description:
  Objectives ; To determine whether cardiac magnetic resonance (CMR) in vivo T1-mapping can measure myocardial area at risk (AAR) compared with microspheres or T2-mapping CMR. ; Background ; If T2-weighted CMR is abnormal in the AAR due to edema related to myocardial ischemia, then T1-weighted CMR should also be able to detect and accurately quantify AAR. ; Methods ; Dogs (n=9) underwent a 2 hour coronary occlusion followed by 4 hours of reperfusion. CMR of the left ventricle was performed for mapping of T1 and T2 prior to any contrast administration. AAR was defined as regions which had a T1 or T2 value (ms) greater than 2SD from remote, and regions with microsphere blood flow (ml/min/g) during occlusion less than 2SD from remote. Infarct size was determined by triphenyltetrazolium chloride staining. ; Results ; The relaxation parameters T1 and T2 were increased in the AAR compared to remote myocardium (T1: 1133±55 vs. 915±33ms, T2: 71±6 vs. 49±3 ms; mean±SD). On a slice-by-slice basis (n=78 slices), AAR by T1- and T2-mapping correlated (R2=0.95, p<0.001) with good agreement (0.4±16.6 % of slice, mean±2SD). On a whole-heart analysis, T1 measurements of left ventricular mass, AAR and myocardial salvage correlated to microsphere measures (R2=0.94) with good agreement (−1.4±11.2 g of myocardium; mean±2SD). Corresponding T2 measurements of left ventricular mass, AAR, and salvage correlated to microsphere analysis (R2=0.96, agreement 1.6±9.2 g of myocardium; mean±2SD). Median infarct size was 30% of the AAR (range 12–52). ; Conclusions ; For determining area at risk after acute myocardial infarction, non-contrast T1-mapping and T2-mapping sequences yield similar quantitative results, and both agree well with microspheres. The relaxation properties T1 and T2 both change in a way that is consistent with the presence of myocardial edema following myocardial ischemia/reperfusion.
• Keywords:
  • magnetic resonance imaging
  • ischemia
  • myocardium at risk
  • myocardial infarction
  • microspheres
  • Animals
  • Coronary Circulation
  • Disease Models, Animal
  • Dogs
  • Edema, Cardiac
  More +
• Source:
  JACC Cardiovasc Imaging. 2012; 5(6):596-603
• Pubmed ID:
  22698528
• Pubmed Central ID:
  PMC3769169
• Document Type:
  Journal Article
• Funding:
  ZIA HL004607/ImNIH/Intramural NIH HHSUnited States/ ; ZIA HL004607-14/ImNIH/Intramural NIH HHSUnited States/ ; ZIA HL006136-02/ImNIH/Intramural NIH HHSUnited States/ ; HL-CR-05-004/HL/NHLBI NIH HHSUnited States/ ; 1 Z01 HL004607-08 CE/CE/NCIPC CDC HHSUnited States/ ; Z01 HL004607/ImNIH/Intramural NIH HHSUnited States/ ; ZIA HL006136-01/ImNIH/Intramural NIH HHSUnited States/ ; ZIA HL006136/ImNIH/Intramural NIH HHSUnited States/
• Volume:
  5
• Issue:
  6
• Download URL:
  https://stacks.cdc.gov/view/cdc/33624/cdc_33624_DS1.pdf
• File Type:
  [PDF - 1.61 MB]
• Collection(s):
  CDC Public Access
• Main Document Checksum:
  urn:sha256:110367fa04228d8e901bb7e8f9beae1f0ac7e5ba4a8e1d31e646db77462de5db