ABSTRACT
Objective:To evaluate the application value of conventional echocardiography and two-dimensional speckle tracking imaging (2D-STI) in assessing the left ventricular systolic and diastolic functions in patients with restrictive cardiomyopathy (RCM).Methods:Fifteen patients confirmed as RCM by cardiac magnetic resonance imaging or pathological biopsy in Fuwei Cardiovascular Hospital of Yunnan Province from September 2017 to June 2020 were selected. According to left ventricular ejection fraction(LVEF), they were divided into LVEF retention group(LVEF≥50%, 8 cases) and LVEF reduction group (LVEF<50%, 7 cases). Meanwhile, 20 healthy volunteers were selected as the control group. Conventional echocardiography and 2D-STI were used to evaluate left ventricular systolic and diastolic function, including left ventricular end-diastolic diameter (LVEDd), LVEF, mitral valve blood flow spectrum peak E/peak A, peak E deceleration time (EDT), tissue Doppler mitral valve ring average early diastolic peak velocity (e′), E/e′ ratio, isovolumetric relaxation time (IVRT), left atrial volume index (LAVI) and speed of tricuspid regurgitation (TVR), tricuspid annular plane systolic excursion (TAPSE), left ventricular longitudinal strain (LS) and circumferential strain (CS). Then the differences and similarities between the two RCM groups and the control group were compared.Results:There was no significant difference of LVEF between LVEF retention group and the control group ( P>0.05), and LVEF in LVEF reduction group was significantly lower than that in control group ( P<0.05). LVEDd in LVEF retention group was significantly smaller than that of LVEF reduction group ( P<0.05), but was not statistically different from the control group ( P>0.05). Values of E/A, E/e′, LAVI and TVR in LVEF retention group and LVEF reduction group were significantly greater than the control group (all P<0.05), and there was no statistically significant difference between the two RCM groups ( P<0.05). Values of e′, EDT, IVRT and TAPSE in LVEF retention group and LVEF reduction group were significantly lower than the control group (all P<0.05), and there was no statistically significant difference between the two RCM groups (all P>0.05). The global LS and LS of AP4, AP3, and AP2 showed significantly different among the 3 groups (all P<0.05). The global and basal, middle, apical segmental CS in LVEF retention group were significantly larger than those in LVEF reduction group (all P<0.05), but they were not significantly different from the control group (all P>0.05). Conclusions:All patients with RCM show left ventricular diastolic dysfunction in conventional echocardiography, and show gradually reduced left ventricular systolic function and left ventricular remodeling. RCM patients with normal LVEF demonstrate decreased myocardial systolic function, and left ventricular global LS could be used as a sensitive indicator to predict myocardial systolic function.
ABSTRACT
Objective To investigate the value of diffusion kurtosis imaging (DKI) in diagnosing early diabetic nephropathy. Methods Twelve pigs were divided into the experimental group (7 pigs) and the control group (5 pigs), used the random number table method. The experimental group was fed with high?fat high?sugar diet,and then repeatedly injected small doses(50 mg/kg) of Streptozotocin (STZ) through the ear vein. Meanwhile,the control group was fed with normal diet and injected with the same dose of citric acid?sodium citrate buffer solution.After the type 2 diabetes was established successfully, T1WI, T2WI and DKI sequence imaging were performed every month for 2 pigs from the experimental group and the control group,respectively.Mean kurtosis(MK), axial kurtosis (K∥), radial kurtosis (K⊥), fractional anisotropy (FA) and mean diffusivity(MD) were measured on the pseudo?color map of the post?processing workstation. fasting blood glucose(GLU),insulin (INS),renal function, urine routines and random albumin creatinine ratio(RACR) were measured before MRI scan. Specimens from bilateral kidneys were taken for pathological examination after MRI scan. The paired t test was used to compare the parameter values of the cortex and medulla. Independent sample t test was used tocompare the parameter values of the experimental group and the control group. Results In the experimental group,the MK, FA values of medulla were 0.66±0.07 and 0.19± 0.04, the MK, FA values of cortex were 0.60±0.06 and 0.16±0.03.In the control group,the MK, FA values of medulla were 0.59±0.03 and 0.20±0.04, the MK, FA values of cortex were 0.53±0.03 and 0.17±0.04.The MK and FA values of medulla were increased compared with the cortex and the difference were statistically significant (P<0.01). The MK, K⊥ values of cortex and medulla were increased in the experimental group compared with the control group and the difference were statistically significant (P<0.05). There was no significant differences in the K∥, FA and MD values between two groups (both cortex and medulla, P>0.05). Conclusion DKI sequencehas certain value in the diagnosis of early diabetic nephropathy, and to some extent reveals the pathological change in early diabetic nephropathy.