In vivo contrast free chronic myocardial infarction characterization using diffusion-weighted cardiovascular magnetic resonance.
J Cardiovasc Magn Reson
; 16: 68, 2014 Sep 17.
Article
em En
| MEDLINE
| ID: mdl-25230598
ABSTRACT
BACKGROUND:
Despite the established role of late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) in characterizing chronic myocardial infarction (MI), a significant portion of chronic MI patients are contraindicative for the use of contrast agents. One promising alternative contrast free technique is diffusion weighted CMR (dwCMR), which has been shown ex vivo to be sensitive to myocardial fibrosis. We used a recently developed in vivo dwCMR in chronic MI pigs to compare apparent diffusion coefficient (ADC) maps with LGE imaging for infarct characterization.METHODS:
In eleven mini pigs, chronic MI was induced by complete occlusion of the left anterior descending artery for 150 minutes. LGE, cine, and dwCMR imaging was performed 8 weeks post MI. ADC maps were derived from three orthogonal diffusion directions (b = 400 s/mm2) and one non-diffusion weighted image. Two semi-automatic infarct classification methods, threshold and full width half max (FWHM), were performed in both LGE and ADC maps. Regional wall motion (RWM) analysis was performed and compared to ADC maps to determine if any observed ADC change was significantly influenced by bulk motion.RESULTS:
ADC of chronic MI territories was significantly increased (threshold 2.4 ± 0.3 µm2/ms, FWHM 2.4 ± 0.2 µm2/ms) compared to remote myocardium (1.4 ± 0.3 µm2/ms). RWM was significantly reduced (threshold 1.0 ± 0.4 mm, FWHM 0.9 ± 0.4 mm) in infarcted regions delineated by ADC compared to remote myocardium (8.3 ± 0.1 mm). ADC-derived infarct volume and location had excellent agreement with LGE. Both LGE and ADC were in complete agreement when identifying transmural infarcts. Additionally, ADC was able to detect LGE-delineated infarcted segments with high sensitivity, specificity, PPV, and NPV. (threshold 0.88, 0.93, 0.87, and 0.94, FWHM 0.98, 0.97, 0.93, and 0.99, respectively).CONCLUSIONS:
In vivo diffusion weighted CMR has potential as a contrast free alternative for LGE in characterizing chronic MI.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Imagem Cinética por Ressonância Magnética
/
Imagem de Difusão por Ressonância Magnética
/
Infarto do Miocárdio
/
Miocárdio
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
J Cardiovasc Magn Reson
Assunto da revista:
ANGIOLOGIA
/
CARDIOLOGIA
/
DIAGNOSTICO POR IMAGEM
Ano de publicação:
2014
Tipo de documento:
Article