Details:

Alternative Title:
JACC Cardiovasc Imaging
Personal Author:
Ugander, Martin ; Bagi, Paul S. ; Oki, Abiola J. ; Chen, Billy ; Hsu, Li-Yueh ; ... More +
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. Less -
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.


Subject:
[+]
Animals
Article
Coronary Circulation
Disease Models, Animal
Dogs
Edema, Cardiac
Fluorescent Dyes
Image Interpretation, Computer-Assisted
Ischemia
Magnetic Resonance Imaging
Microcirculation
Microspheres
Myocardial Infarction
Myocardial Perfusion Imaging
Myocardium
Myocardium At Risk
Observer Variation
Predictive Value Of Tests
Reproducibility Of Results
Magnetic Resonance Imaging
Microspheres

Source:
JACC Cardiovasc Imaging. 2012; 5(6):596-603.
Pubmed ID:
22698528
Pubmed Central ID:
PMC3769169
Document Type:
Journal Article
Funding:
ZIA HL004607-14/Intramural NIH HHS/United States ; ZIA HL006136-01/Intramural NIH HHS/United States ; ZIA HL006136-02/Intramural NIH HHS/United States ; HL-CR-05-004/HL/NHLBI NIH HHS/United States ; 1 Z01 HL004607-08 CE/CE/NCIPC CDC HHS/United States ; ... More +
ZIA HL004607-14/Intramural NIH HHS/United States ; ZIA HL006136-01/Intramural NIH HHS/United States ; ZIA HL006136-02/Intramural NIH HHS/United States ; HL-CR-05-004/HL/NHLBI NIH HHS/United States ; 1 Z01 HL004607-08 CE/CE/NCIPC CDC HHS/United States ; Z01 HL004607/HL/NHLBI NIH HHS/United States Less -
Collection(s):
CDC Public Access
Main Document Checksum:
[+]
urn:sha256:110367fa04228d8e901bb7e8f9beae1f0ac7e5ba4a8e1d31e646db77462de5db
File Type:

Supporting Files

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