Assessment of Myocardial Perfusion and Systolic Function in Patients with Coronary Artery Disease after Coronary Artery Bypass Surgery by Myocardial Contrast Echocardiography and Two-dimensional Strain Echocardiography

The clinically applied value of myocardial perfusion and systolic function in patients with coronary artery disease after coronary artery bypass surgery using real-time myocardial contrast echocardiography （RT-MCE） combined with two-dimensional strain echocardiography was assessed. Twenty patients underwent intravenous RT-MCE by intravenous injections of SonoVue before and after coronary artery bypass surgery. Two-dimensional images were recorded from the left ventricular four-chamber view, two-chamber view and the apical view before, and two weeks and three months after coronary artery bypass surgery, and the peak systolic longitudinal strain was measured. The results showed that myocardial perfusion was significantly increased after coronary artery bypass surgery in about 71.6% segments. In the group that myocardial perfusion was improved, the peak systolic longitu- dinal strain three months after bypass surgery was significantly higher than that before operation [（-15.78±5.91）% vs （-10.45±8.31）%, P〈0.05]. However, the parameters did not change in the group without myocardial perfusion improvement [（-10.33±6.53）% vs （-9.41±6.09）%, P〉0.05]. It was concluded that whether or not the improvement of myocardial perfusion can mirror the recovery trend of regional systolic function, two-dimensional strain echocardiography can observe dynamic change of regional systolic function. The combination of myocardial perfusion with two-dimensional strain echocardiography can more accurately assess the curative effectiveness of coronary artery bypass surgery.

Evaluation of Epirubicin-induced Cardiotoxicity by Two-dimensional Strain Echocardiography in Breast Cancer Patients

The value of two-dimensional strain echocardiography for assessing left ventricular regional systolic function in breast cancer patients who were treated with epirubicin was evaluated. A total of 116 breast cancer patients were divided into 3 groups： Thirty-eight patients in group A were given epirubicin （Epi） of 120-340 mg/m^2, 42 patients in group B received epimbicin of≥ 360 mg/m^2, and 36 patients after surging without chemotherapy served as the control group C. High frame rate two-dimensional images were recorded from apical long-axis view, four-chamber view, two-chamber view of left ventricle. Peak systolic strain of left ventricular subendocardial myocardium was measured using two-dimensional strain software. The conventional echocardiographic parameters were also obtained. Conventional echocardiography showed there was no significant changes in conventional echocardiographic parameters among the three groups （P〉0.05）. Two-dimensional strain echocardiography revealed that the peak systolic strain of left ventricular subendocardial myocardium in group A was reduced in some segments as compared with the controls （P〈0.05）. The peak systolic strain of left ventricular subendocardial myocardium in group B was reduced significantly as com- pared with group C （P〈0.05）, but that was reduced in group B just in some of the segments as compared with group A （P〈0.05）. It was concluded that two-dimensional strain echocardiography could early and sensitively display the effects of epirubicin-induced cardiotoxicity on the systolic function of left ventricular subendocardial myocardium, and early monitor the epirubicin-induced cardiotoxicity.

Two-dimensional plane strain consolidation of unsaturated soils considering the depth-dependent stress

In practical engineering,the total vertical stress in the soil layer is not constant due to stress diffusion,and varies with time and depth.Therefore,the purpose of this paper is to investigate the effect of stress diffusion on the two-dimensional(2D)plane strain consolidation properties of unsaturated soils when the stress varies with time and depth.A series of semi-analytical solutions in terms of excess pore air and water pressures and settlement for 2D plane strain consolidation of unsaturated soils can be derived with the joint use of Laplace transform and Fourier sine series expansion.Then,the inverse Laplace transform of the semi-analytical solution is given in the time domain using a self-programmed code based on Crump’s method.The reliability of the obtained solutions is proved by the degeneration.Finally,the 2D plots of excess pore pressures and the curves of settlement varying with time,considering different physical parameters of unsaturated soil stratum and depth-dependent stress,are depicted and analyzed to study the 2D plane strain consolidation properties of unsaturated soils subjected to the depthdependent stress.

Strain engineering and hydrogen effect for two-dimensional ferroelectricity in monolayer group-Ⅳmonochalcogenides MX(M=Sn,Ge;X=Se,Te,S)

Two-dimensional(2D)ferroelectric compounds are a special class of materials that meet the need for devices miniaturization,which can lead to a wide range of applications.Here,we investigate ferroelectric properties of monolayer group-IV monochalcogenides MX(M=Sn,Ge;X=Se,Te,S)via strain engineering,and their effects with contaminated hydrogen are also discussed.GeSe,GeTe,and GeS do not go through transition up to the compressive strain of-5%,and consequently have good ferroelectric parameters for device applications that can be further improved by applying strain.According to the calculated ferroelectric properties and the band gaps of these materials,we find that their band gap can be adjusted by strain for excellent photovoltaic applications.In addition,we have determined the most stable hydrogen occupancy location in the monolayer SnS and SnTe.It reveals that H prefers to absorb on SnS and SnTe monolayers as molecules rather than atomic H.As a result,hydrogen molecules have little effect on the polarization and electronic structure of monolayer SnTe and SnS.

Two-dimensional speckle tracking echocardiography for the assessment of atrial function

Echocardiography is the most common diagnostic method for assessing atrial function but the technique has some limitations. Traditionally, assessment of left atrial function has been performed by measuring volumes with 2D echocardiography. Additionally, it can be assessed with transmitral Doppler and pulmonary vein Doppler. Recently, an alternative method has been incorporated, namely, measurement of myocardial deformation with color tissue Doppler-derived strain. However, this method has several limitations, such as suboptimal reproducibility, angle-dependence, signal artifacts and the fact that it only measures regional strain and does not obtain information about the curved portion of the atrial roof. To overcome these limitations in the quantification of atrial function, the use of speckle tracking echocardiography (STE) strain has been proposed. This technique is not derived from Doppler but rather from 2D echocardiography; it is angle-independent and allows one to measure global as well as regional atrial strain. In this editorial, we describe the physical and pathophysiological concepts of STE and underline the clinical usefulness of this new technique.

Effect of strain on structure and electronic properties of monolayer C_(4)N_(4)

The first-principles calculations are performed to examine structural,mechanical,and electronic properties at large strain for a monolayer C_(4)N_(4),which has been predicted as an anchoring promising material to attenuate shuttle effect in Li–S batteries stemming from its large absorption energy and low diffusion energy barrier.Our results show that the ideal strengths of C_(4)N_(4)under tension and pure shear deformation conditions reach 13.9 GPa and 12.5 GPa when the strains are 0.07 and 0.28,respectively.The folded five-membered rings and diverse bonding modes between carbon and nitrogen atoms enhance the ability to resist plastic deformation of C_(4)N_(4).The orderly bond-rearranging behaviors under the weak tensile loading path along the[100]direction cause the impressive semiconductor–metal transition and inverse semiconductor–metal transition.The present results enrich the knowledge of the structure and electronic properties of C_(4)N_(4)under deformations and shed light on exploring other two-dimensional materials under diverse loading conditions.

Evaluation of the Effect of Sigmoid-Shaped Interventricular Septum on Left Ventricular Systolic Function in Patients with Essential Hypertension by Two-Dimensional Speckle Tracking Echocardiography

Objective: To evaluate left ventricular regional and global systolic function by measuring left ventricular longitudinal strain (LS) in hypertensive patients with sigmoid-shaped interventricular septum (SIS) by two-dimensional speckle tracking (2D-STE);in order to explore whether the sigmoid-shaped interventricular septum affects the left ventricular systolic function in patients with hypertension. Methods: Routine echocardiographic parameters were measured in 30 hypertensive patients with SIS (SIS group) and 30 hypertensive patients without SIS (non-SIS group). The left ventricular segments and global LS were measured by 2D-STE, and the two sets of parameters were compared. Results: The value of the thickness of the basal segment of the interventricular septum (IVSBT), the thickness of the middle segment of the interventricular septum (IVSMT) and the ratio of the basal segment of the ventricular septum to the middle segment of the interventricular septum (IVSBT/IVSMT) in SIS group was higher than that in non-SIS group. However, the value of left ventricular outflow tract diameter (LVOTD) in SIS group was lower than that in non-SIS group. There was a significant difference between the two groups (all P Conclusion: SIS affects left ventricular regional systolic function of patients with hypertension. 2D-STE can early evaluate left ventricular longitudinal systolic function in hypertensive patients with SIS.

Advances in the Research Application of Ultrasound Non-Invasive Stress-Strain Loop Technology in Cardiovascular Diseases

The ultrasound pressure-strain loop (PSL) technique is a non-invasive method of examining myocardial work, which takes into account the effect of cardiac afterload on deformation and combines the overall longitudinal strain force of the left ventricle with the changes in the left ventricular pressure, allowing earlier detection of possible subclinical cardiac damage in patients, and a more accurate and non-invasive assessment of the patient’s myocardial work performance. In this article, we will discuss the progress of PSL applications in cardiovascular diseases.

Assessment of Regional Left Ventricular Myocardial Function in Rats after Acute Occlusion of Left Anterior Descending Artery by Two-dimensional Speckle Tracking Imaging

This study evaluated the change in regional left ventricular myocardial function in rats following acute occlusion of the left anterior descending coronary artery （LAD） by using two-dimensional speckle tracking imaging （2D-STI）. Sixty Wistar rats were randomly divided into two groups, a myocardial infarction （MI） group, in which 50 rats were subjected to LAD occlusion for 30–45 min, and a sham-operated （SHAM） group that contained 10 rats serving as control. Echo-cardiography was performed at baseline and 1, 4 and 8 week（s） after the operation. High frequency two-dimensional images of left ventricular short axis at papillary muscle level were recorded. Peak systolic radial strain （PRS） and circumferential strain （PCS） were measured in the mid-ventricle in short-axis view by using EchoPAC workstation. Left ventricular internal diameter at diastole （LVIDd） and systole （LVIDs）, fractional shortening （FS）, ejection fraction （EF） and left ventricular mass （LVM） were measured by anatomical M-model echocardiography. Infarct size was measured using triphenyl tetrazolium chloride （TTC） staining 1 week and 8 weeks after the operation. Fibrosis of left ventricu-lar myocardium was displayed using Van Gieson staining 1 week after the infarction. In terms of the TTC staining results, the left ventricle fell into three categories： infarcted, peri-infarcted and remote myocardial regions. Compared with those at baseline and in the SHAM group, （1） PRS and PCS in the infarcted, peri-infarcted and remote myocardial regions were significantly decreased in the MI group within 1 week after the operation （P〈0.05） and the low levels lasted 8 weeks; （2） Compared with those at baseline, LVIDd, LVIDs, FS, EF and LVM in the MI group showed no significant dif-ference 1 week after the operation （P〉0.05）. However, LVIDd, LVIDs and LVM were increased sig-nificantly 4 and 8 weeks after the operation （P〈0.05）, and FS and EF were decreased substantially （P〈0.05）. Van Gieson staining showed that fibrosis developed in all the three myocardial regions to varying degrees. It is concluded that 2D-STI is non-invasive and can be used to assess regional func-tion of myocardium with different blood supply in rats following acute occlusion of the LAD, and can be used as a sensitive and reliable means to follow up the process of left ventricular remodeling.

Assessment of Left Ventricular Longitudinal Regional Myocardial Systolic Function by Strain Imaging Echocardiography in Patients with Hypertrophic Cardiomyopathy

To assess the left ventricular longitudinal regional myocardial systolic function by strain imaging （SI） echocardiography and to study the relationship between regional myocardial systolic function and left ventricular structure in patients with hypertrophic cardiomyopathy （HCM）. S1 echocardiography were performed in 18 patients with HCM and 17 healthy subjects. For each wall, regional myocardial systolic strain was analyzed at the basal, mid, and apical level respectively. And the peak systolic strain was measured. Our results showed that the patients with HCM had reduced peak systolic strain at almost each segment of different walls when compared with healthy subjects. There was significant correlation between the mid-septum peak systolic strain and the thickness of IVS, so was the correlation between the mid-septum peak systolic strain and the IVS to LVPW thickness ratio. This study demonstrated that the left ventricular longitudinal regional myocardial systolic function was abnormal in HCM, and this kind of abnormalities existed extensively in hypertrophic and non-hypertrophic cardiac segments. The degrees of left ventricle hypertrophy and asymmetry are related to the myocardial regional systolic function in HCM.

Left Ventricle Geometry Remolding after Heart Transplantation:A Two-dimensional Ultrasound Study

The function of the transplanted heart will be affected by acute allograft rejection, chronic rejection, high blood pressure and so on, which may induce the reconstruction of the left ventricle and the increase of left ventricular mass （LVM）, and eventually lead to left ventricular hypertrophy that will significantly affect the prognosis of heart transplantation （HT）. The purpose of this study was to dy- namically monitor the changes of left ventricular geometric patterns after HT using two-dimensional echocardiography and to understand the remodeling process and its possible influencing factors. The left ventricular internal diameter, interventricular septal wall thickness, posterior wall thickness at end dias- tole were measured and the relative wall thickness （RWT）, left ventricular mass, left ventricular mass index were calculated respectively in 34 HT patients and 34 healthy volunteers by two-dimensional echocardiography. The type of left ventricular geometry was identified based on the echocardiographic determination of LVM index （LVMI） and RWT. The HT patients were divided into three groups ac- cording to the time length after surgery： A （3 months postoperatively）, B （6 months postoperatively） and C （12 months postoperatively）. We compared the parameters of left ventricle between HT group and normal control group, and explored the risk factors causing the increase of LVM. The results showed that 4 patients （16%） in group A had concentric remodeling. Nine patients （34.62%） in group B had re- construction, including 5 cases of concentric remodeling, 2 cases of concentric hypertrophy and 2 cases of eccentric hypertrophy. The hypertrophy incidence rate was 15.4% in group B. 15 patients （62.5%） had reconstruction in group C, including 9 cases of concentric remodeling, 5 cases of concentric hyper- trophy, and 1 case of eccentric hypertrophy. The prevalence of hypertrophy was 25%. Multivariate analysis showed that hypertension and acute rejection history were the risk factors that resulted in left ventricular hypertrophy. It is concluded that the left ventricular remodeling occurs following cardiac transplantation at an early stage and the incidence of left ventricular hypertrophy increases with survival time. In this study, the one-year prevalence of left ventricular hypertrophy was 25% after surgery. Hy- pertension and acute rejection history are risk factors that can predict the left ventricular hypertrophy.

Magnetic and electronic properties of two-dimensional metal-organic frameworks TM_(3)(C_(2)NH)_(12)

The ferromagnetism of two-dimensional(2D)materials has aroused great interest in recent years,which may play an important role in the next-generation magnetic devices.Herein,a series of 2D transition metal-organic framework materials(TM-NH MOF,TM=Sc-Zn)are designed,and their electronic and magnetic characters are systematically studied by means of first-principles calculations.Their structural stabilities are examined through binding energies and ab-initio molecular dynamics simulations.Their optimized lattice constants are correlated to the central TM atoms.These 2D TM-NH MOF nanosheets exhibit various electronic and magnetic performances owing to the effective charge transfer and interaction between TM atoms and graphene linkers.Interestingly,Ni-and Zn-NH MOFs are nonmagnetic semiconductors(SM)with band gaps of 0.41 eV and 0.61 eV,respectively.Co-and Cu-NH MOFs are bipolar magnetic semiconductors(BMS),while Fe-NH MOF monolayer is a half-semiconductor(HSM).Furthermore,the elastic strain could tune their magnetic behaviors and transformation,which ascribes to the charge redistribution of TM-3d states.This work predicts several new 2D magnetic MOF materials,which are promising for applications in spintronics and nanoelectronics.

First-principles study of a new BP_(2)two-dimensional material

Two-dimensional materials have a wide range of applications in many aspects due to their unique properties. Here we carry out a detailed structural search and design of the BP2using the first principles method, and find a new PMM2 sheet.The analysis of the phonon dispersive curves shows that the 2D PMM2 is dynamic stable. The study of molecular dynamics shows that the 2D PMM2 can be stable under high temperature, even at 600 K. Most importantly, when a suitable strain is applied, the structure can exhibit other electronic properties such as direct band gap semiconductor. In addition, the small strain can tune the band gap value of the PMM2 structure to around 1.4 e V, which is very close to the ideal band gap of solar materials. Therefore, the 2D PMM2 may have potential applications in the field of photovoltaic materials.

Speckle Tracking Echocardiography Identifies Impaired Longitudinal Strain as a Common Deficit in Various Cardiac Diseases

The use of speckle-tracking echocardiography(STE)is becoming an increasingly useful tool in the evaluation of myocardial disease.STE software can track the motion of the specular pattern created by the interference of ultrasound with the myofibers of the heart and provide a quantitative means to evaluate subtle changes in ventricular function that often occur before changes in ventricular ejection fraction are observed.STE is most often used to measure the change in shape(strain)of myocardial segments in the circumferential,radial,and longitudinal directions.In various diseases,including coronary artery disease,aortic stenosis,and mitral regurgitation,deficits in longitudinal strain appear to occur earlier than deficits in other measures of strain or in ejection fraction.Consideration of STE measures of left ventricular contraction has the potential to significantly affect clinical management and outcomes of ischemic and valvular heart disease given the ability to separate those with asymptomatic disease who may benefit from earlier interventions than current guidelines may suggest.

Value of two-dimensional speckle tracking imaging in quantitative assessment of left ventricular function in patients with OSAS

Objective: To research the clinical application of two-dimensional speckle tracking imaging (2D-STI) in quantitative assessment of left ventricular function in patients with obstructive sleep apnea-hypopnea syndrome (OSAS). Method: From July 2016 to December 2018, 86 patients with OSAS were selected as OSAS group. According to sleep apnea hypopnea index (AHI), they were divided into mild OSAS group (24 cases), moderate OSAS group (29 cases) and severe OSAS group (33 cases). Another 50 healthy volunteers who underwent physical examination in our hospital during the same period were selected as the control group. The left ventricular function of all patients was quantitatively assessed by 2D-STI. The left ventricular function of all patients was quantitatively assessed by 2D-STI. The results of routine echocardiography and left ventricular global strain parameters of the OSAS group, the control group and the OSAS patients with different severity were compared and analyzed. Result: There were no significant differences in the levels of left ventricular ejection fraction (LVEF), left ventricular end diastolic diameter (LVEDd), left ventricular end systolic diameter (LVESd) between the two groups and OSAS patients with different severity (P>0.05). The levels of IVST, LVPW and LVMI in the OSAS group were significantly higher than those in the control group, the levels of end-diastolic interventricular septal thickness (IVS), left ventricular posterior wall thickness (LVPW), left ventricular mass index (LVMI) in the severe OSAS group were significantly higher than those in the mild and moderate OSAS group, and the levels of IVST, LVPW and LVMI in the moderate OSAS group were significantly higher than those in the mild OSAS group, there were significant differences between groups (P<0.05). The levels of GLS, GRS and GCS in the OSAS group were significantly lower than those in the control group (P<0.05). GLS, GRS and GCS levels in the severe OSAS group were significantly lower than those in the mild OSAS group and the moderate OSAS group, while the levels of global longitudinal strain (GLS), global radial strain (GRS) and global circumferential strain (GCS) in the moderate OSAS group were significantly lower than those in the mild OSAS group (P<0.05). Conclusion: The left ventricular systolic function of OSAS patients is obviously impaired. Left ventricular function in OSAS patients can be assessed timely and accurately by two-dimensional speckle tracking imaging.

Effects of Strain Channel on Electron Irradiation Tolerance of InP-based HEMT Structures

The introduction of strain In_(x)Ga_(1-x)As channel with high In content increases the confinement of the two-dimensional electron gas(2DEG)and further improves the high-frequency performance of InGaAs/InAlAs/InP HEMTs.The effect of In_(x)Ga_(1-x)As channel with different In contents on electron irradiation tolerance of InP-based HEMT structures in terms of 2DEG mobility and density has been investigated.The experiment results show that,after the same high electron irradiation dose,the 2DEG mobility and density in InP-based HEMT structures with strain In_(x)Ga_(1-x)As(x>0.53)channel decrease more dramatically than that without strain In_(0.53)Ga_(0.47)As channel.Moreover,the degradation of 2DEG mobility and density becomes more severe as the increase of In content and strain in the In_(x)Ga_(1-x)As channel.The research results can provide some suggestions for the design of radiation-resistant InP-based HEMTs.

超声心动图监测45例法布雷病患者心脏早期受累的特征分析

【目的】分析45例临床确诊的法布雷病(AFD)患者的临床特征,同时应用超声心动图二维斑点追踪技术(2D-STE)评估法布雷病患者应变图像,以期探索法布雷患者心脏早期受累在超声心动图(UCG)上的表现。【方法】本研究为观察性研究。共纳入确诊为AFD的患者45例,根据UCG测量左室壁有无肥厚,分为左室壁肥厚组(17例,室间隔或左室后壁厚度≥12 mm)和无左室壁肥厚组(28例)。收集患者基线资料,并对所有患者进行常规UCG检查及二维斑点追踪超声心动图分析。应用TomTec工作站分析超声心动图图像,比较两组的临床基线资料、UCG常规参数及心肌应变特征。【结果】本研究共纳入45例AFD患者,年龄(32.33±16.11)岁,其中男性27例(60.00%)。左室壁肥厚组17例(37.78%),无左室壁肥厚组28例(62.22%)。45例患者的左室射血分数(LVEF)均正常(>50%)。与无左室壁肥厚组相比,左室壁肥厚组患者的靶器官受累比例明显增加。与无左室壁肥厚组相比,左室壁肥厚组患者的E/A,平均E/E'明显升高(P<0.05);左室壁肥厚组的整体、心肌层、心内膜以及各节段的纵向应变(LS),周向应变(CS)及径向应变(RS)的差异均无统计学意义(P值均>0.05)。AFD患者心肌层的整体和各节段LS、CS的绝对值均低于心内膜的对应值(P值均<0.05)。AFD患者的中间段的LS、RS绝对值较基底段和心尖段高(P值均<0.05)。【结论】早期收缩功能障碍与左室壁厚度无明显关系。2D-STE心肌应变可以早期监测AFD室壁肌层受累较心内膜严重,而中间段受累较心尖段和基底段轻。

基于人工智能的自动应变定量技术评价慢性肾病患者早期心肌损伤的临床价值

目的探讨基于人工智能的自动应变定量技术评价慢性肾病(CKD)患者早期心肌损伤的临床价值。方法选取2021年7月至2023年7月我院收治的CKD患者125例为研究对象,根据CKD分期分别纳入A组(2~3期,67例)、B组(4~5期,58例),另选取同期45例健康体检者为对照组。比较3组二维超声心动图参数[左室射血分数(LVEF)、舒张末期室间隔厚度(IVSd)、舒张末期左室后壁厚度(LVPWd)、左心室舒张末期内径(LVEDD)、右心室内径(RVD)]、血清N末端脑钠肽前体(NT-pro BNP)水平、自动及手动应变定量技术应变参数[左心室整体纵向收缩期峰值应变(LVGLS)、右心室整体纵向收缩期峰值应变(RVGLS)、左房储备期纵向应变(LASr)、左房管道期纵向应变(LAScd)、左房收缩期纵向应变(LASct)],采用Pearson分析自动应变参数与手动应变参数、二维超声心动图参数及血清NT-pro BNP水平的相关性,比较LVGLS、RVGLS、左房应变分析的手动、自动应变分析时间,采用受试者工作特征(ROC)曲线分析自动应变参数联合检测对CKD患者早期心肌损伤的诊断价值。结果B组LVEF水平低于A组、对照组,B组IVSd、LVPWd、LVEDD、RVD及血清NT-pro BNP水平高于A组、对照组,且A组高于对照组,差异有统计学意义(P<0.05);B组自动及手动LVGLS、RVGLS、LAScd、LASct均高于A组、对照组,B组LASr低于A组、对照组,且A组自动LVGLS、RVGLS、LAScd、LASct高于对照组,LASr低于对照组,A组手动LAScd、LASct高于对照组,LASr低于对照组,差异有统计学意义(P<0.05);自动分析各应变参数与手动分析各参数均呈正相关(r=0.852,0.721,0.605,0.630,0.627,P<0.05);自动LVGLS、RVGLS、LAScd、LASct与LVEF呈负相关(r=-0.659,-0.598,-0.612,-0.601,P<0.05),与NT-pro BNP呈正相关(r=0.643,0.638,0.622,0.647,P<0.05);自动LASr与LVEF呈正相关(r=0.629,P<0.05),与NT-pro BNP呈负相关(r=-0.658,P<0.05)。自动病变分析时间较手动分析时间明显减少,差异有统计学意义(P<0.05)。LVGLS诊断CKD患者早期心肌损伤的曲线下面积(AUC)为0.928(95%CI:0.889~0.957),约登指数为0.736,最佳诊断敏感度为87.20%,特异度为86.40%,差异有统计学意义(P<0.05)。结论自动应变定量技术应变参数联合检测对CKD患者早期心肌损伤具有一定诊断价值,可作为临床评估早期心肌损伤的有效检查方式,并对后续治疗具有一定指导价值。

左室压力-应变环评估终末期肾病透析患者左室收缩功能的临床价值

目的探讨左室压力-应变环(LV-PSL)评估终末期肾病血液透析和腹膜透析患者左室收缩功能的临床应用价值。方法选取于我院就诊的79例慢性肾脏病5期患者,其中血液透析组29例、腹膜透析组27例及未透析组23例,均行常规超声心动图检查并获取相关参数,应用自动心肌功能成像分析软件获取左室整体纵向应变(GLS)及心肌做功指数(MWI),包括整体做功指数(GWI)、整体有效功(GCW)、整体无效功(GWW)、整体做功效率(GWE),比较各组上述参数的差异。分析MWI与常规超声心动图参数、GLS、血压、透析时间、透析方式的相关性。结果各组常规超声心动图参数和GLS比较差异均无统计学意义。血液透析组GWI、GCW均低于腹膜透析组和未透析组,GWW高于腹膜透析组和未透析组,GWE低于腹膜透析组,差异均有统计学意义(均P<0.05)。相关性分析显示,GWI、GCW与GLS、左室射血分数(LVEF)、收缩压、舒张压均呈正相关,与室间隔厚度(IVS)、透析时间、透析方式均呈负相关(均P<0.05);GWW与透析方式呈正相关,与GLS呈负相关(均P<0.05);GWE与GLS、LVEF均呈正相关,与IVS、左室后壁厚度、透析方式均呈负相关(均P<0.05)。结论血液透析对终末期肾病患者左室收缩功能的影响较腹膜透析更大,LV-PSL能准确评估该类患者左室收缩功能,具有较好的临床应用价值。

三维斑点追踪技术评估非瓣膜性心房颤动患者左房低电压区对左房结构及功能的影响

目的应用三维斑点追踪技术(3D-STI)评估非瓣膜性心房颤动(以下简称房颤)患者不同程度左房低电压区(LVA)对左房结构及功能的影响。方法选取我院拟行射频消融术的非瓣膜性房颤患者66例,术前均行经胸超声心动图检查获得左房收缩末期前后径、左右径、上下径和左室舒张末期内径、左室射血分数、二尖瓣口舒张早期峰值血流速度与二尖瓣环峰值运动速度比值(E/e’);3D-STI获得左房储器期应变(LASr)、管道期应变(LAScd)、泵功能期应变(LASct)及左房射血分数(LAEF)。进行射频消融术时应用三维电解剖标测技术获得LVA,根据LVA面积占左房总面积的百分比定义LVA程度,将患者分为无LVA患者组(Ⅰ组)29例、LVA程度<10%组(Ⅱ组)26例、LVA程度≥10%组(Ⅲ组)11例,比较各组临床资料和超声心动图参数的差异;分析左房应变参数与LVA的相关性。结果Ⅲ组陈旧性脑梗死或一过性脑缺血、持续性房颤占比及CHA_(2)DS_(2)-VASc评分均高于Ⅰ组、Ⅱ组,差异均有统计学意义(均P<0.05)。Ⅰ组与Ⅲ组、Ⅱ组与Ⅲ组E/e’>14者占比比较,差异均有统计学意义(均P<0.05);其余常规超声心动图参数比较,差异均无统计学意义。Ⅲ组LASr、LAScd、LASct、LAEF均低于Ⅰ组、Ⅱ组,差异均有统计学意义(均P<0.05)。相关性分析显示,LASr、LAScd、LASct均与LVA呈负相关(r=-0.538、-0.448、-0.501,均P<0.05)。结论当LVA达到10%时,房颤患者左房结构虽未发生改变,但其功能已经减低;应用3D-STI可以早期发现非瓣膜性房颤患者LVA程度对左房功能的影响。