Yoo Jin Hong MD, Abstract Co-Author: Nothing to Disclose

Chul hwan Park MD, Presenter: Nothing to Disclose

Young Jin Kim MD, Abstract Co-Author: Nothing to Disclose

Jin Hur MD, Abstract Co-Author: Nothing to Disclose

Hye-Jeong Lee MD, Abstract Co-Author: Nothing to Disclose

Sae Rom Hong MD, Abstract Co-Author: Nothing to Disclose

Young Joo Suh MD, Abstract Co-Author: Nothing to Disclose

Yun Jung Kim MD, Abstract Co-Author: Nothing to Disclose

Dong Jin Im, Abstract Co-Author: Nothing to Disclose

Tae Hoon Kim MD, Abstract Co-Author: Nothing to Disclose

Byoung Wook Choi MD, Abstract Co-Author: Nothing to Disclose

To evaluate whether the extra-cellular volume fraction (ECV) measured using cardiac MRI can detect myocardial tissue changes in dilated cardiomyopathy (DCM) without late gadolinium enhancement (LGE).

Forty-one DCM patients (26 men, 15 women; mean age, 52.8 ± 16.4 years; range, 17–84 years), and 10 healthy volunteers (7 men, 3 women; mean age, 53.5 ± 4.0 years; range, 48–60 years) underwent pre- and post- T1 mapping using a modified Look-Locker inversion recovery (MOLLI) sequences, LGE, and cine MRI on a clinical 3-T cardiac magnetic resonance (CMR) system. LGE-MR findings were used to divide DCM patients into two groups: Group A had no apparent LGE, and Group B had LGE apparent in at least one segment. The average ECV of left ventricle (LV) myocardium (16 segments) was calculated in short-axis view using the myocardial T1 value, LV blood pool T1 value, and hematocrit as follows: ECV = [(ΔR1 of myocardium/ΔR1 of LV blood pool)] × (1 - hematocrit), where R1=1/T1, ΔR1=Post-contrast R1 - Pre-contrast R1. The LV ejection fraction (LVEF) was obtained from cine MRI images using Simpson’s method. The mean myocardial ECV in DCM patients without obvious LGE segments (Group A+B) was compared to that of controls. The mean myocardial ECV in Group A was compared to Group B segments without obvious LGE. The correlation between LV systolic function and the mean myocardial ECV of the whole myocardium was evaluated in all groups.

Among the 41 DCM patients, 22 were in Group A, and 19 were in Group B. The mean ECV of DCM patents (n = 41, 568 segments, 30.7% ± 5.9) was significantly higher (p < 0.001) than that of the control group (n = 10, 157 segments, 25.6% ± 3.2). When ECV was correlated with LVEF measured by cine MRI, the ECV was inversely related to LVEF in Group A (r = -0.551, p = 0.008), Group B (r = -0.525, p = 0.021), and Group A+B (r = -0.550, p < 0.001).

The ECV measured by MRI could be a useful parameter in evaluating diffuse myocardial changes in DCM patients.  

The results of our study showed that quantification of the ECV using CMR was an effective method for detecting myocardial changes in DCM patients, even in cases where LGE was not apparent in the myocardium. The ECV measured using the T1 mapping technique could be a useful non-invasive tool to replace endomyocardial biopsy.

Hong, Y, Park, C, Kim, Y, Hur, J, Lee, H, Hong, S, Suh, Y, Kim, Y, Im, D, Kim, T, Choi, B, Extracellular Volume Fraction in Dilated Cardiomyopathy Patients without Obvious Late Gadolinium Enhancement: Comparison With Healthy Control Subjects.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14016865.html