Characterization of Compacted Myocardial Abnormalities by Cardiac Magnetic Resonance With Native T1 Mapping in Left Ventricular Non-Compaction Patients　– A Comparison With Late Gadolinium Enhancement –

Abstract

Background: Native T1 mapping is an emerging cardiac magnetic resonance technique for quantitative evaluation of cardiomyopathies. This study aimed to investigate the usefulness of native T1 mapping in characterizing myocardial abnormalities in left ventricular non-compaction (LVNC) by comparing it with late gadolinium enhancement (LGE). Methods and Results:The study group of 31 LVNC patients and 8 normal controls underwent cardiovascular magnetic resonance to acquire the native T1 maps and LGE images. Of the 31 LVNC patients, 14 had LGE. The mean native T1 value of the normal controls, LGE(−) and LGE(+) patients was 1,098.8±40.8 ms, 1140.6±32.8 ms, and 1181.4±53.7 ms, respectively. Significant differences were found in native T1 between any 2 groups (F=9.74, P<0.001). In discriminating the presence of LGE in LVNC patients, the odds ratio and corresponding 95% confidence interval (CI) of native T1 were, respectively, 2.966 (95% CI: 1.123-7.835, P=0.028) and 4.348 (95% CI: 1.155-16.363, P=0.030) before and after adjusting for confounding factors with an increment of 1 standard deviation. Conclusions:The finding that LGE(−) patients had elevated native T1 compared with normal controls suggested native T1 mapping can be used earlier than LGE imaging to detect myocardial fibrosis in LVNC patients. Furthermore, higher native T1 values in LGE(+) patients than in the LGE(−) group suggested native T1 mapping is more sensitive than LGE imaging for identifying myocardial fibrosis in LVNC patients. 1211 Native T1 Mapping Evaluates Myocardium Abnormality factors for cardiac disease (diabetes mellitus, hypertension, and smoking) were enrolled as normal controls. The age and sex of the normal volunteers were matched with the LVNC patient group. Clinical information was collected from the medical record. The study protocol was approved by the local Institutional review board and written informed consent was given by all subjects. CMR ProtocolThe CMR imaging was performed with a 3.0-T MR system (Achieva TX, Philips Healthcare, Best, The Netherlands) using a 32-channel phased array heart coil (InVivo, Gainesville, FL, USA). The cine, phase-sensitive inversion recovery (PSIR), and modified look-locker inversion recovery (MOLLI) image sequences were acquired. 16 The ECG-gated balanced steadystate free precession (bSSFP) cine images of the long-and short-axis (SAX) images covering the entire LV were acquired with the following parameters: TR/TE 2.7/1.3 ms with 30 heart phases; voxel size 1.8×1.5×8.0 mm 3 ; slice thickness 8 mm; and slice spacing 2 mm. The PSIR sequence was acquired 15±5 min after the injection of 0.2 mmol/kg of gadolinium-DTPA (Magnetism, Bayer Schering Pharma, Guangzhou, China) with flow rate of 3 ml/s and 20 ml saline for flushing. The LGE images were obtained during mid-diastole in the same SAX orientations as cine, covering the whole LV, with the following imaging

Micro-Computed Tomography for the Quantitative 3-Dimensional Assessment of the Compact Myocardium in the Mouse Embryo

“…31 Despite these limitations, the need to study and develop new and more accurate imaging techniques is underscored by recent human studies suggesting that the commonly used definition of LVNC as a trabeculated to compact myocardium ratio >2.3 needs to be reconsidered. [40][41][42] Overall, the data and methodology presented in this study represent the proof-of-principle that the mouse ventricular wall can be structurally resolved and evaluated in 3D with micro-CT, providing a valid addition to the traditional 2D histological assessment of compact myocardial thickness in mouse embryos. Although the present study was performed on iodine-stained fixed specimens, it demonstrates what is methodologically achievable, including spatial resolution, using current imaging and image analysis techniques.…”

Hypertrabeculated Left Ventricular Myocardium in Relationship to Myocardial Function and Fibrosis: The Multi-Ethnic Study of Atherosclerosis

“…Besides these reports of focal fibrosis or scars in patients with LVNC, Jenni et al (26) revealed interstitial fibrosis as a finding in six of seven hearts with a diagnosis of LVNC. Zhou et al (27) recently reported subjects with a diagnosis of LVNC had a significantly longer native T1 time measure in the clinic, it is not specific (33.2% [247 of 745] of subjects in the MESA cohort with NCC . 2.3).…”

Is T1-Mapping Truly Superior to Late Gadolinium Enhancement-Imaging in Demonstrating Myocardial Fibrosis in Myopathy- and Non-Myopathy Associated Noncompaction?

“…Table 1 in the paper indicates that the family history was significantly more often positive for LVHT in LGE− LVHT patients as compared with LGE+ LVHT patients. 1 What is the explanation for LGE− LVHT patients more frequently having a positive family history for LVHT than the LGE+ LVHT patients? The finding suggests that LGE− LVHT patients more frequently have a genetic background than LGE+ LVHT patients.…”

“…Finally, group sizes should be increased to draw final conclusions. 1 We have the following comments and concerns. We do not agree with the statement that higher T1-values in LGE+ LVHT patients than in LGE− LVHT patients suggest that T1-mapping is more sensitive than LGE for demonstration of myocardial fibrosis.…”