Diagnosis of Acute Global Myocarditis Using Cardiac MRI with Quantitative T1 and T2 Mapping: Case Report and Literature Review

박철환,최의영,Andreas Greiser,Mun Young Paek,황성호,김태훈 대한영상의학회 2013 Korean Journal of Radiology Vol.14 No.5

The diagnosis of myocarditis can be challenging given that symptoms, clinical exam findings, electrocardiogram results, biomarkers, and echocardiogram results are often non-specific. Endocardial biopsy is an established method for diagnosing myocarditis, but carries the risk of complications and false negative results. Cardiac magnetic resonance imaging (MRI) has become the primary non-invasive imaging tool in patients with suspected myocarditis. Myocarditis can be diagnosed by using three tissue markers including edema, hyperemia/capillary leak, and necrosis/fibrosis. The interpretation of cardiac MR findings can be confusing, especially when the myocardium is diffusely involved. Using T1 and T2 maps, the diagnosis of myocarditis can be made even in cases of global myocarditis with the help of quantitative analysis. We herein describe a case of acute global myocarditis which was diagnosed by using quantitative T1 and T2 mapping.

Role of Myocardial Extracellular Volume Fraction Measured with Magnetic Resonance Imaging in the Prediction of Left Ventricular Functional Outcome after Revascularization of Chronic Total Occlusion of Coronary Arteries

Yinyin Chen,Xinde Zheng,Hang Jin,Shengming Deng,Daoyuan Ren,Andreas Greiser,Caixia Fu,Hongxiang Gao,Mengsu Zeng 대한영상의학회 2019 Korean Journal of Radiology Vol.20 No.1

Objective: The purpose of this study was to prospectively investigate the value of the myocardial extracellular volume fraction (ECV) in predicting myocardial functional outcome after revascularization of coronary chronic total occlusion (CTO). Materials and Methods: Thirty patients with CTO underwent cardiovascular magnetic resonance (CMR) before and 6 months after revascularization. Three baseline markers of functional outcome were evaluated in the dysfunctional segments assigned to the CTO vessels: ECV, transmural extent of infarction (TEI), and unenhanced rim thickness (RIM). At the global level, the ECV values of the whole myocardium with and without a hyperenhanced region (global and remote ECV) were respectively measured. Results: In per-segment analysis, ECV was superior to TEI and RIM in predicting functional recovery (area under receiver operating characteristic curve [AUC]: 0.86 vs. 0.75 and 0.73, all p values < 0.010), and it emerged as the only independent predictor of regional functional outcome (odds ratio [OR] = 0.83, 95% confidence interval [CI]: 0.77–0.89; p < 0.001) independent of collateral circulation. In per-patient analysis, global baseline ECV was indicative of ejection fraction (EF) at the follow-up examination (β = -0.61, p < 0.001) and changes in EF (β = -0.57, p = 0.001) in multivariate regression analysis. A patient with global baseline ECV less than 30.0% (AUC, 0.93; sensitivity 94%, specificity 80%) was more likely to demonstrate significant EF improvement (OR: 0.38; 95% CI: 0.17–0.85; p = 0.019). Conclusion: Extracellular volume fraction obtained by CMR may provide incremental value for the prediction of functional recovery both at the segmental and global levels in CTO patients, and may facilitate the identification of patients who can benefit from revascularization.

Correction with blood T1 is essential when measuring post-contrast myocardial T1 value in patients with acute myocardial infarction

Choi, Eui-Young,Hwang, Sung Ho,Yoon, Young Won,Park, Chul Hwan,Paek, Mun Young,Greiser, Andreas,Chung, Hyemoon,Yoon, Ji-Hyun,Kim, Jong-Youn,Min, Pil-Ki,Lee, Byoung Kwon,Hong, Bum-Kee,Rim, Se-Joong,Kwo BioMed Central 2013 Journal of cardiovascular magnetic resonance Vol.15 No.-

<P><B>Background</B></P><P>Post-contrast T1 mapping by modified Look-Locker inversion recovery (MOLLI) sequence has been introduced as a promising means to assess an expansion of the extra-cellular space. However, T1 value in the myocardium can be affected by scanning time after bolus contrast injection. In this study, we investigated the changes of the T1 values according to multiple slicing over scanning time at 15 minutes after contrast injection and usefulness of blood T1 correction.</P><P><B>Methods</B></P><P>Eighteen reperfused acute myocardial infarction (AMI) patients, 13 cardiomyopathy patients and 8 healthy volunteers underwent cardiovascular magnetic resonance with 15 minute-post contrast MOLLI to generate T1 maps. In 10 cardiomyopathy cases, pre- and post-contrast MOLLI techniques were performed to generate extracellular volume fraction (Ve). Six slices of T1 maps according to the left ventricular (LV) short axis, from apex to base, were consecutively obtained. Each T1 value was measured in the whole myocardium, infarcted myocardium, non-infarcted myocardium and LV blood cavity.</P><P><B>Results</B></P><P>The mean T1 value of infarcted myocardium was significantly lower than that of non-infarcted myocardium (425.4±68.1 ms vs. 540.5±88.0 ms, respectively, p< 0.001). T1 values of non-infarcted myocardium increased significantly from apex to base (from 523.1±99.5 ms to 561.1±81.1 ms, p=0.001), and were accompanied by a similar increase in blood T1 value in LV cavity (from 442.1±120.7 ms to 456.8±97.5 ms, p<0.001) over time. This phenomenon was applied to both left anterior descending (LAD) territory (from 545.1±74.5 ms to 575.7±84.0 ms, p<0.001) and non-LAD territory AMI cases (from 501.2±124.5 ms to 549.5±81.3 ms, p<0.001). It was similarly applied to cardiomyopathy patients and healthy volunteers. After the myocardial T1 values, however, were adjusted by the blood T1 values, they were consistent throughout the slices from apex to base (from 1.17±0.18 to 1.25±0.13, p>0.05). The Ve did not show significant differences from apical to basal slices.</P><P><B>Conclusion</B></P><P>Post-contrast myocardial T1 corrected by blood T1 or Ve, provide more stable measurement of degree of fibrosis in non-infarcted myocardium in short- axis multiple slicing.</P>

Noncontrast Myocardial T1 Mapping by Cardiac Magnetic Resonance Predicts Outcome in Patients With Aortic Stenosis

Lee, Heesun,Park, Jun-Bean,Yoon, Yeonyee E.,Park, Eun-Ah,Kim, Hyung-Kwan,Lee, Whal,Kim, Yong-Jin,Cho, Goo-Yeong,Sohn, Dae-Won,Greiser, Andreas,Lee, Seung-Pyo Elsevier Science B.V. Amsterdam 2018 JACC CARDIOVASCULAR IMAGING Vol.11 No.7

<P><B>Abstract</B></P> <P><B>Objectives</B></P> <P>The aim of this study was to evaluate whether native T1 value of the myocardium on cardiac magnetic resonance (CMR) could predict clinical events in patients with significant aortic stenosis (AS).</P> <P><B>Background</B></P> <P>Although previous studies have demonstrated the prognostic value of focal fibrosis using late gadolinium enhancement (LGE) by CMR in AS patients, the prognostic implication of diffuse myocardial fibrosis by noninvasive imaging remains unknown.</P> <P><B>Methods</B></P> <P>A prospective observational longitudinal study was performed in 127 consecutive patients with moderate or severe AS (68.8 ± 9.2 years of age, 49.6% male) and 33 age- and sex-matched controls who underwent 3-T CMR. The degree of diffuse myocardial fibrosis was assessed by noncontrast mapping of T1 relaxation time using modified Look-Locker inversion-recovery sequence, and the presence and extent of LGE were also evaluated. The AS patients were divided into 3 groups by the native T1 value. Primary endpoint was a composite of all-cause death and hospitalization for heart failure.</P> <P><B>Results</B></P> <P>Native T1 value was higher in AS patients, compared with control subjects (1,232 ± 53 ms vs. 1,185 ± 37 ms; p = 0.008). During follow-up (median 27.9 months), there were 24 clinical events including 9 deaths (6 pre-operative and 3 post-operative), the majority of which occurred in the patients in the highest T1 tertile group (2.4% vs. 11.6% vs. 42.9% for lowest, mid-, and highest tertile groups; p < 0.001 by log-rank test). The total number of events for both pre- and post-operative events also occurred more frequently in patients in the highest T1 tertile group. EuroSCORE II, the presence and/or extent of LGE, and the native T1 value were predictors of poor prognosis (adjusted hazard ratio for every 20-ms increase of native T1: 1.28; p = 0.003). In particular, the highest native T1 value provided further risk stratification regardless of the presence of LGE.</P> <P><B>Conclusions</B></P> <P>High native T1 value on noncontrast T1 mapping CMR is a novel, independent predictor of adverse outcome in patients with significant AS.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>