Dataset Information

Magnetic susceptibility and R2* of myocardial reperfusion injury at 3T and 7T.

ABSTRACT:

Purpose

Magnetic susceptibility (Δχ) alterations have shown association with myocardial infarction (MI) iron deposition, yet there remains limited understanding of the relationship between relaxation rates and susceptibility or the effect of magnetic field strength. Hence, Δχ and R2∗ in MI were compared at 3T and 7T.

Methods

Subacute MI was induced by coronary artery ligation in male Yorkshire swine. 3D multiecho gradient echo imaging was performed at 1-week postinfarction at 3T and 7T. Quantitative susceptibility mapping images were reconstructed using a morphology-enabled dipole inversion. R2∗ maps and quantitative susceptibility mapping were generated to assess the relationship between R2∗ , Δχ, and field strength. Infarct histopathology was investigated.

Results

Magnetic susceptibility was not significantly different across field strengths (7T: 126.8 ± 41.7 ppb; 3T: 110.2 ± 21.0 ppb, P = NS), unlike R2∗ (7T: 247.0 ± 14.8 Hz; 3T: 106.1 ± 6.5 Hz, P < .001). Additionally, infarct Δχ and R2∗ were significantly higher than remote myocardium. Magnetic susceptibility at 7T versus 3T had a significant association (β = 1.02, R² = 0.82, P < .001), as did R2∗ (β = 2.35, R² = 0.98, P < .001). Infarct pathophysiology and iron deposition were detected through histology and compared with imaging findings.

Conclusion

R2∗ showed dependence and Δχ showed independence of field strength. Histology validated the presence of iron and supported imaging findings.

SUBMITTER: Moon BF

PROVIDER: S-EPMC9067599 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature

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Publications

Magnetic susceptibility and R2* of myocardial reperfusion injury at 3T and 7T.

Moon Brianna F BF Iyer Srikant Kamesh SK Josselyn Nicholas J NJ Hwuang Eileen E Swago Sophia S Keeney Samuel J SJ Castillero Estibaliz E Ferrari Giovanni G Pilla James J JJ Gorman Joseph H JH Gorman Robert C RC Tschabrunn Cory M CM Shou Haochang H Matthai William W Wehrli Felix W FW Ferrari Victor A VA Han Yuchi Y Litt Harold H Witschey Walter R WR

Magnetic resonance in medicine 20210806 1

<h4>Purpose</h4>Magnetic susceptibility (Δχ) alterations have shown association with myocardial infarction (MI) iron deposition, yet there remains limited understanding of the relationship between relaxation rates and susceptibility or the effect of magnetic field strength. Hence, Δχ and R2∗ in MI were compared at 3T and 7T.<h4>Methods</h4>Subacute MI was induced by coronary artery ligation in male Yorkshire swine. 3D multiecho gradient echo imaging was performed at 1-week postinfarction at 3T a ...[more]

PMID: 34355815

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Dataset Information

Magnetic susceptibility and R2* of myocardial reperfusion injury at 3T and 7T.

Purpose

Methods

Results

Conclusion

Publications

Magnetic susceptibility and R2* of myocardial reperfusion injury at 3T and 7T.

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