蝮蛇咬伤患者肌酸激酶和肌钙蛋白I的变化与心功能相关性研究

目的 探讨蝮蛇咬伤患者心肌酶学(CK-MB、CK)和肌钙蛋白I(cTnI)变化与心功能的相关性.方法 将106例蝮蛇咬伤患者按病情程度分为轻、重、危重型3组,对3组患者的心肌肌钙蛋白I及心肌酶学、左室Tei指数进行测定并进行比较分析.结果 危重型组患者的CK、CK-MB、Tei指数、cTnI阳性率均高于轻、重型组,差异有显著性(P<0.05).cTnI呈阳性患者的左室Tei指数与CK、CK-MB相关系数为0.311、0.266.结论 cTnI对蝮蛇咬伤患者心肌损伤的敏感性及特异性均高于CK和CK-MB.蝮蛇咬伤中毒患者心肌酶学升高可以判断骨髂肌损伤程度,只有极少数危型蝮蛇咬伤患者合并有心肌损伤,左室Tei指数测定也证实蝮蛇咬伤cTnI呈阳性者均有心功能受损.     

应用Tei指数评价高血压心脏病患者左心室整体功能的研究

目的:探讨超声对高血压心脏病患者左心室整体功能评价的临床价值.方法:69例高血压心脏病患者分为3组:A组26例左室壁厚度正常,B组23例仅室间隔增厚,C组20例室间隔与左室后壁均增厚,同时选择正常健康者D组48人为对照.常规行超声心动图检查,测量并计算出二尖瓣口血流频谱舒张早期和舒张晚期血流峰值之比(E/A)、左室射血分数(LVEF)及Tei指数等评价参数.结果:高血压心脏病A、B组LVEF值均在正常范围,C组LVEF值有所下降,但与对照组比较差异均无统计学意义(P>0.05),但E/A值均较对照组减小(P<0.05);高血压心脏病A、B和C组Tei指数分别为(0.49±0.15)、(0.56±0.10)和(0.56±0.10),高于正常对照组的(0.32±0.08)(P<0.05).结论:在LVEF正常情况下Tei指数能更早地全面反映高血压心脏病患者左心功能下降情况,并且不受心率、心室几何形态,心室收缩和舒张压等因素的影响,为临床早期干预治疗防止心衰发生提供了依据.     

超声心动图Tei指数对不同血糖控制水平妊娠期糖尿病孕妇胎儿心功能及出生后整体心功能的评估价值

目的:探讨超声心动图Tei指数对不同血糖控制水平妊娠期糖尿病(GDM)孕妇胎儿心功能及出生后整体心功能的评估价值。方法:选择2017年2月至2019年10月期间我院产科接诊的134例GDM患者,根据血糖控制水平将其分为良好组(餐前空腹血糖≤5.3 mmol/L,餐后2 h血糖≤6.7 mmol/L,睡前血糖>3.3 mmol/L,妊娠期糖化血红蛋白<5.5%,65例)和不良组(餐前空腹血糖>5.3 mmol/L,餐后2 h血糖>6.7 mmol/L,睡前血糖≤3.3 mmol/L,妊娠期糖化血红蛋白≥5.5%,69例),另选择50例正常妊娠孕妇为对照组。分别于妊娠3238周、新生儿出生后17 d采用超声心动图测量胎儿、新生儿心功能和Tei指数。比较胎儿、新生儿心功能、Tei指数的差异。结果:不良组胎儿左室射血分数(LVEF)、二尖瓣E/A峰的速度比值(E/AMV)、右室舒张末期内径(RVDd)、右室收缩末期内径(RVDs)、左室短轴缩短率(LVFS)、左心室Tei指数、右心室Tei指数均高于良好组和对照组(P<0.05),三尖瓣E/A峰速度比值(E/ATV)低于良好组和对照组(P<0.05)。良好组LVFS高于对照组(P<0.05),良好组LVEF、E/AMV、E/ATV、RVDd、RVDs、左心室Tei指数、右心室Tei指数与对照组比较无统计学差异(P>0.05)。不良组新生儿LVEF、E/AMV、RVDd、RVDs、LVFS、左心室Tei指数、右心室Tei指数均高于良好组和对照组(P<0.05),E/ATV低于良好组和对照组(P<0.05)。良好组LVFS高于对照组(P<0.05),良好组LVEF、E/AMV、E/ATV、RVDd、RVDs、左心室Tei指数、右心室Tei指数与对照组比较无统计学差异(P>0.05)。结论:超声心动图Tei指数可敏感地反映GDM孕妇胎儿以及新生儿心功能损伤,妊娠期有效控制血糖水平有助于保护胎儿心功能。     

蹲起试验评价大学生心功能的效用研究

目的:探讨3种不同负荷蹲起试验方法对评价普通大学生心功能的效用.方法:采用60s60次蹲起、45s45次蹲起、30s30次蹲起3种不同运动负荷试验,测量和计算累积心功指数、即刻心功指数,并与VO2max作相关性分析.结果:60s60次蹲起测得的心功指数与VO2max的相关系数最高,45s45次蹲起的心功指数次之,30s30次最低;而3种不同负荷方法各自的即刻心功指数与VO2max的相关系数均高于累积心功指数.结论:60s60次蹲起试验评价心功能效度最高,30s30次最低;即刻心功指数比累积心功指数评价效度更高.     

右室Tei指数与血清醛固酮水平对COPD患者发生房颤的预测价值研究

摘要 目的：探讨右室Tei指数、血清醛固酮水平对慢性阻塞性肺病(COPD)患者发生房颤的预测价值。方法：根据房颤的发生情况,将200例COPD患者分为房颤发生组和无房颤发生组。比较两组的病程、COPD严重程度、血清醛固酮(ALD)水平及右室Tei指数、肺动脉压、右心室横径的差异,分析右室Tei指数和ALD预测房颤发生的ROC曲线下面积、截断值、灵敏度及特异度。结果：房颤发生组病程(8.48±1.3和7.59±1.75)、右心室横径(40.52±2.74和36.27±2.4)、血清ALD(137.64±42.77和98.61±15.39)、右室Tei指数(0.37±0.12和0.31±0.07)、COPD、肺动脉高压的严重程度与无房颤发生组比较差异都有统计学意义(P<0.05)。logistic回归分析结果显示ALD、右室Tei指数、病程、和肺动脉高压程度为影响COPD患者发生房颤的独立影响因素。右室Tei指数预测房颤发生的ROC曲线下面积AUC=0.645,截断值为0.420,灵敏度为38.0%,特异度达到93.33%;ALD预测房颤发生的ROC曲线下面积为0.792,截断值为122.72 pg/mL,灵敏度为66.0%,特异度可达到98.0%。结论：右室Tei指数和血清醛固酮水平可作为慢性阻塞性肺病患者发生房颤的预测参考指标。     

基于主成分分析的双对比光学投影断层成像

目的 本文提出了一种基于主成分分析（PCA）的双对比光学投影断层成像（DC-OPT）方法,以获得活体中血流网络和骨骼的三维可视化。方法 使用主成分分析方法来提取吸收图像和血流图像,原始图像序列的第一主成分用于获取吸收图像;通过计算每个像素的调制深度来获得流动图像。不同投影位置的流动和吸收对比图像被用于三维血流网络和骨骼的同步重建。结果 采用PCA和OPT相结合的方法,通过将动态血流信号和静态背景信号分离,实现了对微生物样本的血流网络和骨骼的三维成像。结论 本文研究的新颖之处在于通过同一光学系统获得了快速、同步、双对比的血流网络和骨骼三维图像。实验结果可用于活体生物的生理发育研究。     

磁处理白术药液对小白鼠免疫器官指数影响的药效研究

目的 :从免疫学方面探讨磁处理白术药液对小白鼠免疫器官指数影响的药效作用。方法 :用不同强度的磁处理白术药液及非磁处理白术药液对小白鼠进行腹腔注射 ,连续 7d ,每天一次 ,末次给药 1 2h后处死 ,称其体重 ,取出胸腺、脾脏及肝脏 ,称重 ,计算各器官指数。结果 :与正常对照组比较 ,磁处理白术药液组对小白鼠的肝脏指数、脾脏指数均有极显著的提高 (P <0 .0 1 ) ,胸腺指数也有影响 ,但差异不显著 (P>0 .0 5 ) ;与非磁处理药液组比较 ,磁处理药液组对小白鼠的肝脏指数、脾脏指数、胸腺指数有影响 ,但差异不显著 (P >0 .0 5 )。结论 :磁处理白术药液对免疫器官指数有明显作用     

双指数模型在高b值弥散加权成像中的初步研究

目的采用双指数分析模型探讨弥散加权信号强度的衰减规律,揭示脑组织的弥散信息。材料和方法对豆状核、内囊、额叶自质、丘脑等感兴趣区的每一像素,使用Matlab优化工具箱中的lsqcurvefit（）函数对b值从500s／mm。到3500s／mm。共计7个b值图像的信号强度值进行拟合,并与单指数拟合的结果进行比较。结果双指数模型对信号强度的拟合优于单指数模型,并能获得三个新参数。结论双指数模型能更好的拟合高b值时图像信号强度．所得的三个参数能从不同角度提供大脑的弥散信息．但其生理基础有待于进一步研究。     

人手部皮下微循环特性随深度变化的研究

本研究使用手持式扫频光学相干层析(SSOCT)系统分别在人左手无名指指甲上方、无名指指腹和手掌大拇指根部选取3 mm×3 mm区域进行了在体成像,使用指数补偿方法还原血流信息,获取不同深度的血流正面光学断层图像(en face图像),从血管灌注密度(PD)、血管直径(VD)两个方面分析了微循环随深度的变化特性。试验结果证明,在上述三个成像位置中,随着成像深度的增加,血管PD与血管VD均增大,血流信息的丰富程度增加,但同时en face图像的清晰度有所下降。其中左掌大拇指根部微血管最为细密,血流信息较为丰富,比较适宜作为微循环疾病诊断研究的成像部位。分层投影结果显示,左手无名指指甲上方部位在成像深度较浅(220～660μm)时,血管PD明显小于其他两个成像部位,说明此处在该范围内血流信息丰富程度不够。本文测量了随深度变化的手部血流几何学特征,验证了光学相干层析(OCT)技术基于手部皮下微循环光学断层图像进行疾病诊断的可行性。许多微循环疾病早期就已经产生了微血管病变,因此对这种微循环变化的探测在疾病的早期诊断方面具有临床指导意义。     

基于图像处理的树叶面积测量系统

以数字图像处理技术为基础,对数码相机拍摄的含有参照硬板和树叶的照片进行图像分析处理,提出了获取树叶的实际面积测量系统的一种独特实现方案。采用此方案开发出相应的应用软件,应用于树叶面积的测量计算,获得十分满意的结果。     

组织多普勒Tei指数对妊娠期糖尿病孕妇胎儿心功能的评估价值及母婴预后与血糖控制水平的关系研究

目的:探讨组织多普勒Tei指数对妊娠期糖尿病(GDM)孕妇胎儿心功能的评估价值,并分析母婴预后与血糖控制水平的关系。方法:选取2017年1月到2018年6月期间在我院行产前检查的GDM孕妇80例,根据血糖控制情况将其分为良好组(48例)和不良组(32例)。另选取同期在我院行产前检查的并在我院生产的健康孕妇50例作为对照组。比较三组研究对象的等容收缩时间(ICT)、等容舒张时间(IRT)、射血时间(ET)、Tei指数、妊娠结局以及新生儿并发症。结果:不良组的ET小于良好组和对照组,Tei指数大于良好组和对照组,差异均有统计学意义(P0.05),不良组的巨大儿、早产、羊水过多、胎儿窘迫的发生率高于良好组和对照组,差异均有统计学意义(P0.05),不良组的新生儿低血糖、高胆红素血症的发生率高于良好组和对照组,差异均有统计学意义(P0.05)。结论:组织多普勒Tei指数对GDM孕妇胎儿心功能具有较高的评估价值,可敏感地检测出胎儿心功能异常,血糖控制不良会明显增加不良妊娠结局和新生儿并发症的发生率。     

心脏彩超评估高血压左心室肥厚伴左心衰竭患者心功能的临床价值及与NYHA分级的关系研究

目的:探讨心脏彩超评估高血压左心室肥厚(LVH)伴左心衰竭患者心功能的临床价值,分析其超声指标与美国纽约心脏病协会(NYHA)分级的相关性。方法:选择2017年5月至2018年5月我院收治的127例高血压LVH伴左心衰竭患者为观察组,根据NYHA分级将其分为NYHAⅡ级组(41例)、Ⅲ级组(47例)、Ⅳ级组(39例),另选择100例体检的健康志愿者为对照组。所有受试者均接受心脏彩超获得相关参数[左心房内径(LAD)、左心室舒张末期内径(LVEDD)、左心室收缩末期内径(LVESD)、左心室短轴缩短率(LVFS)、左心室后壁厚度(LVPWT)、室间隔厚度(IVST)、左心室射血分数(LVEF)、左心室舒张早期充盈峰最大充盈速度/舒张晚期充盈峰最大峰值速度(E/A)比值、Tei指数],分析心脏彩超相关参数与NYHA分级之间相关性。结果:观察组患者LAD、LVEDD、LVESD、LVPWT、IVST、Tei指数高于对照组(P0.05),LVFS、LVEF、E/A比值低于对照组(P0.05)。Tei指数随着NYHA分级增高而增高(P0.05),LVFS、LVEF、E/A比值随着NYHA分级增高而降低(P0.05)。Spearman秩相关分析结果显示,Tei指数与NYHA分级呈正相关(rs=0.398,P0.05),LVFS、LVEF、E/A比值与NYHA分级呈负相关(rs=-0.285,-0.442,-0.305,P0.05)。结论:高血压LVH伴左心衰竭患者发生明显左室肥厚和左心功能降低,心脏彩超可准确评估高血压LVH伴左心衰竭患者的心功能和病情严重程度,且部分心脏彩超相关参数与NYHA分级相关。     

Validation of echocardiographic and Doppler indexes of left ventricular relaxation in adult hypertensive and normotensive rats

This study was performed to validate echocardiographic and Doppler techniques for the assessment of left ventricular (LV) diastolic function in spontaneously hypertensive rats (SHR) and normotensive Wistar rats. In 11 Wistar rats and 20 SHR, we compared 51 sets of invasive and Doppler LV diastolic indexes. Noninvasive indexes of LV relaxation were related to the minimal rate of pressure decline (-dP/dt(min)), particularly isovolumic relaxation time (IVRT), the Tei index, the early velocity of the mitral annulus (E(m)) using Doppler tissue imaging, and early mitral flow propagation velocity using M-mode color (r = 0.28-0.56 and P < 0.05-0.0001). When the role of systolic load was considered, the correlation between Doppler indexes of LV diastolic function and relaxation rate [(-dP/dt(min))/LV systolic pressure] improved (r = 0.48-0.86 and P = 0.004-0.0001, respectively). Similarly, Doppler indexes of LV diastolic function and the time constant of isovolumic LV relaxation (tau) correlated well (r = 0.50-0.84 and P = 0.0002-0.0001, respectively). In addition, eight SHR and eight Wistar rats were compared; their LV end-diastolic diameters were similar, whereas the SHR LV mass was greater. Furthermore, IVRT and Tei index were significantly higher and E(m) was lower in SHR. Moreover, tau was higher in SHR, demonstrating impaired LV relaxation. In conclusion, LV relaxation can be assessed reliably using echocardiographic and Doppler techniques, and, using these indexes, impaired relaxation was demonstrated in SHR.     

Estimation of valvular resistance of segmented aortic valves using computational fluid dynamics

Aortic valve stenosis is associated with an elevated left ventricular pressure and transaortic pressure drop. Clinicians routinely use Doppler ultrasound to quantify aortic valve stenosis severity by estimating this pressure drop from blood velocity. However, this method approximates the peak pressure drop, and is unable to quantify the partial pressure recovery distal to the valve. As pressure drops are flow dependent, it remains difficult to assess the true significance of a stenosis for low-flow low-gradient patients. Recent advances in segmentation techniques enable patient-specific Computational Fluid Dynamics (CFD) simulations of flow through the aortic valve. In this work a simulation framework is presented and used to analyze data of 18 patients. The ventricle and valve are reconstructed from 4D Computed Tomography imaging data. Ventricular motion is extracted from the medical images and used to model ventricular contraction and corresponding blood flow through the valve. Simplifications of the framework are assessed by introducing two simplified CFD models: a truncated time-dependent and a steady-state model. Model simplifications are justified for cases where the simulated pressure drop is above 10 mmHg. Furthermore, we propose a valve resistance index to quantify stenosis severity from simulation results. This index is compared to established metrics for clinical decision making, i.e. blood velocity and valve area. It is found that velocity measurements alone do not adequately reflect stenosis severity. This work demonstrates that combining 4D imaging data and CFD has the potential to provide a physiologically relevant diagnostic metric to quantify aortic valve stenosis severity.     

A new approach for the evaluation of the severity of coarctation of the aorta using Doppler velocity index and effective orifice area: in vitro validation and clinical implications

Early detection and accurate estimation of COA severity are the most important predictors of successful long-term outcome. However, current clinical parameters used for the evaluation of the severity of COA have several limitations and are flow dependent. The objectives of this study are to evaluate the limitations of current existing parameters for the evaluation of the severity of coarctation of the aorta (COA) and suggest two new parameters: COA Doppler velocity index and COA effective orifice area. Three different severities of COAs were tested in a mock flow circulation model under various flow conditions and in the presence of normal and stenotic aortic valves. Catheter trans-COA pressure gradients and Doppler echocardiographic trans-COA pressure gradients were evaluated. COA Doppler velocity index was defined as the ratio of pre-COA to post-COA peak velocities measured by Doppler echocardiography. COA Doppler effective orifice area was determined using continuity equation. The results show that peak-to-peak trans-COA pressure gradient significantly increased with flow rate (from 83% to 85%). Peak Doppler pressure gradient also significantly increased with flow rate (80-85%). A stenotic or bicuspid aortic valve increased peak Doppler pressure gradient by 20-50% for a COA severity of 75%. Both COA Doppler velocity index and COA effective orifice area did not demonstrate significant flow dependence or dependence upon aortic valve condition. As a conclusion, COA Doppler velocity index and COA effective orifice area are flow independent and do not depend on aortic valve conditions. They can, then, more accurately predict the severity of COA.     

Computational Phlebology: The Simulation of a Vein Valve

We present a three-dimensional computer simulation of the dynamics of a vein valve. In particular, we couple the solid mechanics of the vein wall and valve leaflets with the fluid dynamics of the blood flow in the valve. Our model captures the unidirectional nature of blood flow in vein valves; blood is allowed to flow proximally back to the heart, while retrograde blood flow is prohibited through the occlusion of the vein by the valve cusps. Furthermore, we investigate the dynamics of the valve opening area and the blood flow rate through the valve, gaining new insights into the physics of vein valve operation. It is anticipated that through computer simulations we can help raise our understanding of venous hemodynamics and various forms of venous dysfunction.     

Study of endothelium-dependent blood oscillations in the human skin microcirculatory bed

Cutaneous microcirculation parameters were studied with laser Doppler flowmetry in healthy volunteers. To investigate endothelial-dependent peripheral blood flow oscillations the iontophoresis of 1% acetylcholine solution was carried out. To estimate the contribution of rhythmical components in blood flow signal the continuous wavelet-transform spectral analysis was used. To reveal correlation between microcirculation parameters under study the correlation analysis was used. The microcirculation index was shown to be the factor producing cross-correlation dependences. The only positive significant correlation between the blood flow oscillation amplitude in the range of endothelial activity normalized to mean microcirculation index at rest and maximal microcirculation index during the iontophoresis of acetylcholine was revealed.     

Influence of the atrio-ventricular delay optimization on the intra left ventricular delay in cardiac resynchronization therapy

The severity index is a new echocardiographic measure that is thought to be an accurate indicator of aortic leaflet pathology in patients with AS. However, it has not been validated against cardiac catheterization or Doppler echocardiographic measures of AS severity nor has it been applied to patients with aortic sclerosis. The purposes of this study were to compare the severity index to invasive hemodynamics and Doppler echocardiography across the spectrum of calcific aortic valve disease, including aortic sclerosis and AS. 48 patients with aortic sclerosis and AS undergoing echocardiography and cardiac catheterization comprised the study population. The aortic valve leaflets were assessed for mobility (scale 1 to 6) and calcification (scale 1 to 4) and the severity index was calculated as the sum of the mobility and calcification scores according to the methods of Bahler et al. The severity index increased with increasing severity of aortic valve disease; the severity indices for patients with aortic sclerosis, mild to moderate AS and severe AS were 3.38 ± 1.06, 6.45 ± 2.16 and 8.38 ± 1.41, respectively. The aortic jet velocity by echocardiography and the square root of the maximum aortic valve gradient by cardiac catheterization correlated well with the severity index (r = 0.84, p < 0.0001; r = 0.84, p < 0.0001, respectively). These results confirm that the severity index correlates with hemodynamic severity of aortic valve disease and may prove to be a useful measure in patients with aortic sclerosis and AS.