Mean Scar Entropy by Late Gadolinium Enhancement Cardiac Magnetic Resonance Is Associated With Ventricular Arrhythmias Events in Hypertrophic Cardiomyopathy.

Background: Ventricular arrhythmias are associated with sudden cardiac death (SCD) in hypertrophic cardiomyopathy (HCM). Previous studies have found the late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) was independently associated with ventricular arrhythmia (VA) in HCM. The risk stratification of VA remains complex and LGE is present in the majority of HCM patients. This study was conducted to determine whether the scar heterogeneity from LGE-derived entropy is associated with the VAs in HCM patients. Materials and Methods: Sixty-eight HCM patients with scarring were retrospectively enrolled and divided into VA (31 patients) and non-VA (37 patients) groups. The left ventricular ejection fraction (LVEF) and percentage of the LGE (% LGE) were evaluated. The scar heterogeneity was quantified by the entropy within the scar and left ventricular (LV) myocardium. Results: Multivariate analyses showed that a higher scar [hazard ratio (HR) 2.682; 95% CI: 1.022-7.037; p = 0.039] was independently associated with VA, after the adjustment for the LVEF, %LGE, LV maximal wall thickness (MWT), and left atrium (LA) diameter. Conclusion: Scar entropy and %LGE are both independent risk indicators of VA. A high scar entropy may indicate an arrhythmogenic scar, an identification of which may have value for the clinical status assessment of VAs in HCM patients.

[Assessment of left ventricle volume filling curve with magnetic resonance imaging: a preliminary study].

OBJECTIVE: To conduct a preliminary study on the reliability of left ventricle volume filling curve through the commercial medical program Report-Card 4.0. METHODS: A total pf 22 normal volunteers underwent the examination. Images of standard 2-chamber view and short-axis view were acquired at end-expiration by electrocardiography-gated FIESTA CINE sequence. Then one experienced doctor manually contoured the endocardium during end-systole and end-diastole phases respectively, obtained the results of the volume of end-diastole (EDV) and end-systole (ESV), ejection fraction (EF), stroke volume (SV) and cardiac output (CO), processing time and mean processing time per phase. Papillary muscle was not included into left ventricle volume. Another two observers utilized LV ANALYSIS of Report-Card, generated the left ventricle volume filling curve and recorded the processing time and mean processing time per phase. From the curve, EDV, ESV, SV, EF, CO, peak ejecting rate (PER) and peak filling rate (PFR) were also acquired. One observer repeated the procedures a week later. RESULTS: The difference of results from two methods were insignificant (P > 0.05) and the correlation was excellent (EDV 0.963, ESV 0.944). Intra-observer and inter-observer variability for measurements (EDV, ESV) were assessed by Bland-Altman analysis and interclass correlation coefficient (0.985, 0.987, 0.959 and 0.957 respectively). The mean processing time (179 ± 51) s by means of manually contouring was significantly less than the mean processing time (331 ± 99) s through REPORT-CARD 4.0 (P < 0.001). However, the mean processing time per phase (17 ± 5) s by means of REPORT-CARD 4.0 was significantly less than the mean processing time per phase (89 ± 26) s through manually contouring (P < 0.001). CONCLUSION: The reliability of left ventricle volume filling curve generated through Report-Card is excellent. Left ventricle volume filling curve may be a reliable method of further studying the functions of left ventricle.

TRO19622 promotes myelin repair in a rat model of demyelination.

BACKGROUND/AIMS: Multiple sclerosis is a neurodegenerative autoimmune disease characterized by diffuse oligodendrocyte injury, axonal loss and multifocal demyelination of myelin sheaths in the central nervous system. TRO19622 is a small cholesterol-like compound, which displays remarkable neuroprotective and neuroregenerative properties in neural cell culture and rodent models of nerve trauma. Therefore, the aim of the present study is to evaluate the pharmacological action of TRO19622 on the demyelination/remyelination processes by using a rat model of cuprizone-induced demyelination. METHODS: Using Female Sprague-Dawley rats models of demyelination, we morphologically and functionally assessed the effect of TRO19622 on myelination in vivo. RESULTS: In this study, we first provided in vivo proof that cuprizone intoxication contributed to spatial learning and memory ability injury and that TRO19622 restored neurological function. The structure of myelin injury and repair in cuprizone intoxication rats was then measured by T2-weighted magnetic resonance imaging. These magnetic resonance imaging-based results and trends were confirmed by histological, immunohistochemistry and electron microscopy analyses. CONCLUSIONS: The results clearly showed that TRO19622 promoted myelin formation with consequent functional improvement.

[Image and hemodynamical features of pulmonary artery branches in COPD with pulmonary artery hypertension].

OBJECTIVE: To investigate the imaging and hemodynamical features of pulmonary artery branches in chronic obstructive pulmonary disease (COPD) with pulmonary artery hypertension (PAH). METHODS: CT pulmonary angiography (CTPA) with ECG-gating was performed in 13 patients with clinical diagnosed COPD and 25 normal subjects. The thin-slice multiple plane reconstruction in systole and diastole phase was conducted, which in turn was used to generate the InSpace reconstructed images with reference frame of the main pulmonary artery and the first two grades branches, the contour of the branches was depicted. On the base of coordinates, the GAMBIT was used to generate nodes and furthermore meshes, then the software Fluent was used for numerical calculation and flow simulation. The velocity and pressure changes in the main pulmonary artery and the first two grades branches during different periods of cardiac cycle were observed in both groups. RESULT: CTPA showed that the diameter of the main pulmonary before bifurcate and proximal of the first two branches was larger in systole period than that in diastole period. The diameter of the second segmental artery of right upper lobe was larger during diastole period. The length of the main pulmonary and the first two branches showed no significant difference in both diastole and systole periods. There was no significant difference in length of pulmonary arteries between COPD and normal groups. The main pulmonary to distal right pulmonary artery appeared larger in diastole period. Compared with normal, in COPD group several arteries increased in diameter including proximal and distal of the proximal right pulmonary artery and the proximal right pulmonary artery during systole and diastole periods. In systole period only the diameter of the main pulmonary before bifurcate got larger and the back basic segmental artery of both lower lobe show smaller than normal. The flow condition analysis in COPD and normal groups suggested higher pressure in pulmonary arteries during systole period than that in diastole period, both groups showed high pressure area below the branching point. In COPD patients the right lower lobe artery endured the most significant pressure fall during the two periods and high pressure distributed larger area than normal. Flow velocity in main branch was faster than lower grade branches and that in systole period was faster than that in diastole period. The trend of diffusion of high pressure area was more prominent in diastole period than normal and the influence more prominent. CONCLUSION: The distal part of right pulmonary artery to lower lobe artery may be affected earlier when the pulmonary pressure increased. It is feasible to study the changes of flow condition in pulmonary artery branches though the combination of CTPA image and relevant software.

[Flow simulation of normal pulmonary artery branches based on multiple detectors computed tomography].

OBJECTIVE: To simulate the flow condition in the main pulmonary artery and the branches of left and right pulmonary arteries by combining the images from CT pulmonary angiography (CTPA) by multiple detectors computed tomography (MDCT) and the flow condition data from ultrasonic cardiography. METHODS: The normal enhanced chest CTPA images with ECG-gating from 25 persons undergoing physical examination, 21 males and 4 females, aged 39, underwent thin-slice multiple plane reconstruction in diastolic and systolic periods respectively. These images were stored in the InSpace software. On the base of coordinates GAMBIT software was used to generate the nodes and meshes. FLUENT software was used to simulate the blood flow speed and pressure field distribution. RESULTS: The pressure levels of the main pulmonary artery and the branches of left and right pulmonary arteries were higher during the systolic period. The blood flow velocity was faster during the systolic period too. The right lower lobe artery endured the most significant pressure during both systolic and diastolic periods. However, there were not significant differences in pressure and blood flow velocity between the systolic and diastolic periods in the segmental arteries. CONCLUSION: The right lower lobe artery is the first part to be affected when the pulmonary pressure rises. It is feasible to study the changes of the flow condition in the branches of pulmonary artery through combining CTPA images and relevant softwares.