实时三维超声及组织速度向量评价肺动脉高压患者右心室收缩功能及相关性研究

目的 应用实时三维超声(RT 3DE)及组织速度向量(VVI)技术评价右心室整体及局部收缩功能,预测其在肺动脉高压(PH)患者右心功能衰竭中的价值。方法 选取我院诊断的PH患者86例,根据肺动脉收缩压(PASP)分为轻中度组、重度组,每组43例,选择体检健康人35例作为对照组,应用实时三维超声定量分析右心室三维射血分数（3D RVEF）,右心室三维每搏量（3D RVSV）,右心室三维舒张末容积（3D RVEDV）,右心室三维收缩末容积（3D RVESV）,采用VVI技术分析右心室六个节段心肌纵向应变(L S)、应变率(L SR)、整体应变（Globle S）及应变率（Globle SR）,并分析各参数之间的关系。结果 与对照组比较,轻中度组和重度组3D RVEF 逐渐减低,3D RVEDV、3D RVESV及3D RVSV增高（P<0.01）;3组右心室室间隔心尖段的L SR比较差异无统计学意义（P>0.05）,与对照组比较,两PH组右心室其余各节段L S,L SR均减低（P<0.05）,与轻中度组比较,重度组右心室L S及L SR降低更明显（P<0.05）,与对照组比较,两PH组右心室其余各节段L S,L SR、Globle S及Globle SR均减低（P<0.05）,与轻中度组比较,重度组降低更明显（P<0.05）,3D RVEF与Globle S,Globle SR呈正相关。PASP与Globle S,Globle SR呈负相关,但相关性均不强。结论 肺动脉高压组右心室整体收缩功能有所降低,随着肺动脉压力逐渐增高,右心室各节段纵向应变及应变率逐渐减低,但是在不同程度PH组中,右心室局部收缩功能变化比整体功能变化更早。     

二维斑点追踪技术评价慢性阻塞性肺疾病患者右心室收缩功能

目的 探讨二维斑点追踪成像(2D-STI)技术评价慢性阻塞性肺疾病(COPD)患者右心室收缩功能的临床价值。方法 将58例COPD患者按肺动脉收缩压分为轻度肺动脉高压(MPAH)组和无肺动脉高压(NPAH)组,另选取30名健康志愿者为正常对照组。应用二维应变软件于剑下四腔心切面测量右心室游离壁基底段和中间段的纵向收缩期峰值速度(Vs)、收缩期峰值应变(S)及收缩期峰值应变率(SRs)。对比各组间常规超声参数及二维应变参数的差异。结果 常规超声参数:与正常对照组比较,MPAH组及NPAH组右心室前壁厚度(RVAW)和舒张末期右心室中间段内径均明显增大,MPAH组收缩末期主肺动脉内径(MPA)增大(P均<0.05);与NPAH组比较,MPAH组RVAW和MPA均明显增大(P均<0.05)。二维应变参数:与正常对照组比较,MPAH组和NPAH组右心室游离壁基底段及中间段Vs、S、SRs均显著减低(P均<0.05);与NPAH组比较,MPAH组右心室游离壁基底段及中间段S及Vs均显著减低(P均<0.05)。结论 2D-STI技术是一种早期、客观评价COPD患者右心室收缩功能的新方法。     

二维应变及组织多普勒成像评价无左心室重构高血压患者的右心室长轴舒张功能

目的 探讨超声二维应变(2DS)和组织多普勒成像(TDI)在早期定量评估无左心室重构高血压患者右心室长轴舒张功能中的应用价值。方法 对50例无左心室重构的高血压患者(HT组)和60名健康志愿者(对照组),应用2DS及TDI测量并记录右心室游离壁基底段、中段及心尖段长轴舒张早、晚期峰值速度(Ve、Va),舒张早、晚期峰值应变率(SRe、SRa),计算Ve/Va及SRe/SRa。结果 ①2DS显示,与对照组比较,HT组右心室游离壁各节段SRe、SRe/SRa值均减低(P均<0.05);TDI显示HT组右心室游离壁中段SRe、SRe/SRa值均减低(P均<0.05)。②2DS显示,与对照组比较, HT组右心室游离壁各节段Ve、Ve/Va值均减低(P均<0.05);TDI显示HT组右心室游离壁各节段Ve、Va及Ve/Va值与对照组比较差异均无统计学意义(P均>0.05)。结论 2DS可较TDI更准确地评价无左心室重构高血压患者的右心室长轴舒张功能。     

斑点追踪显像技术评价慢性血栓栓塞性肺动脉高压患者左心室扭转运动

目的 应用超声心动图斑点追踪显像技术(STI)初步评价重度慢性血栓栓塞性肺动脉高压(CTEPH)患者左心室扭转运动特征。 方法 选择31例重度CTEPH患者(CTEPH组)和26名健康志愿者(正常对照组),采集胸骨旁左心室基底水平、心尖水平短轴切面及心尖四腔心、两腔心切面图像。采用Simpson法计算左心室舒张末期和收缩末期容积(LVEDV、LVESV)、左心室射血分数(LVEF)、右心室射血分数(RVEF);分析短轴切面收缩期心内膜下、心外膜下心肌,计算左心室整体扭转角度。 结果 CTEPH组RVEF显著低于正常对照组(P＜0.01);CTEPH组的LVEDV、LVESV较正常对照组减低,但差异均无统计学意义(P均>0.05),两组LVEF差异无统计学意义(P>0.05)。重度CTEPH患者左心室基底部和心尖部整体峰值旋转角度、左心室整体扭转角度明显减低(P均<0.01);基底部心内膜下峰值旋转角度减低(P<0.01)。 结论 重度CTEPH患者左心室扭转功能受损,左心室圆周方向收缩功能障碍。     

速度向量成像技术评价正常人左心室壁形变分布特征

目的 应用速度向量成像(VVI)技术初步评价正常人左心室壁形变特征。 方法 采集并动态存储47名健康志愿者胸骨旁系列左心室短轴观及心尖系列左心室长轴观连续3个心动周期二维灰阶图像,运用VVI软件显示左心室壁各节段应变曲线,并观察各曲线形态特征,对照同步记录心电图测量左心室壁各节段各应变分量收缩期峰值。 结果 正常人左心室壁各应变分量在左心室不同水平间比较差异均无统计学意义(P均＞0.05)。正常人左心室壁各应变分 量收缩期峰值比较径向＞周向＞纵向,且差异有统计学意义(P均＜0.05)。左心室游离壁纵向及周向收缩期峰值应变心内膜测值均显著大于心外膜测值(P均＜0.05);室间隔纵向及周向收缩期峰值应变显示右心室面测值大于左心室面测值,但差异无统计学意义(P＞0.05)。 结论 正常人左心室壁收缩期峰值应变分布具有一定的特征,认识这些特征有助于判断左心室壁异常形变。     

二维斑点追踪技术评价2型糖尿病患者右心室功能

目的 探讨斑点追踪显像(STI)技术评价2型糖尿病(T2DM)患者右心室功能的价值。 方法 依据是否合并糖尿病微血管病变,将44例T2DM患者分为无微血管病变组(T2DM Ⅰ组,n=19)和合并微血管病变组(T2DM Ⅱ组,n=25),另选28名性别、年龄相匹配的健康志愿者为正常对照组(NC组)。应用STI技术于静息状态下采集心尖四腔切面二维图像,分析右心室游离壁各节段峰值应变、应变率指标。 结果 与NC组比较,T2DM Ⅰ组各节段收缩峰值应变率(SRs)、舒张早期峰值应变率(SRe)以及基底部的收缩期峰值应变(ε)和舒张晚期峰值应变率(SRa)减低(P<0.05),T2DM Ⅱ组各节段的ε、SRs、SRe、SRa明显减低(P<0.05);与T2DM Ⅰ组比较,T2DM Ⅱ组基底部的ε、SRs、SRe明显减低,差异有统计学意义(P<0.05)。 结论 STI技术测量右心室游离壁应变及应变率能够无创地评价T2DM患者右心室功能。     

实时三维斑点追踪显像技术评价心肌缺血患者左心室局部功能

目的 应用实时三维斑点追踪显像(3D-STI)技术评价冠状动脉左前降支(LAD)不同狭窄程度缺血患者左心室心肌局部应变变化。方法 根据冠状动脉造影(CAG)结果将138例临床疑诊冠心病患者分为对照组(34例)和狭窄组(104例),另将狭窄组分为轻度狭窄亚组(A亚组,n=34)、中度狭窄亚组(B亚组,n=36)和重度狭窄亚组(C亚组,n=34)。测量LAD供血区域心肌的应变指标:峰值径向应变(PLS)、峰值面积应变(PAS)、应变显像舒张指数(SI-DI),分析2D-STI及3D-STI测值的相关性。结果 对照组3D-STI的PLS较2D-STI值偏低(P<0.05),相关性良好(r值:0.58~0.76)。A亚组PAS与对照组相比差异无统计学意义(P>0.05)。与对照组比较,C亚组全部节段及B亚组前壁中间段及心尖段、前间隔中间段及前间隔心尖段的PAS值减低(P<0.05),C亚组全部节段及B亚组前壁基底段及心尖段、前间隔中间段及前间隔心尖段的SI-DI值减低(P<0.05);与B亚组比较,C亚组的前壁中间段及心尖段的PAS值减低(P<0.05),前壁中间段及心尖段和前间隔心尖段的SI-DI值减低(P<0.05)。结论 3D-STI可有效评估心肌缺血患者左心室局部心肌纤维早期形变特征。     

斑点追踪成像测量三尖瓣环位移评价尿毒症患者右心室功能

目的 应用超声二维斑点追踪成像（2D-STI）技术测量尿毒症患者的三尖瓣环收缩期位移（TAD）,探讨其评价右心室收缩功能的可行性。方法 收集尿毒症患者30例（尿毒症组）,选择同期健康人30名作为对照组。记录心尖四腔心二维图像并输入QLab 8.1工作站,测量右心室纵向应变以及TAD软件测量右心室游离壁三尖瓣环收缩期位移（T1）、三尖瓣环中点收缩期位移（Tm）、右心室长轴缩短率（Tm%）;比较两组TAD参数的差异,并分析右心室纵向应变与TAD各参数的相关性。结果 尿毒症组与对照组间年龄、性别构成比、左心室内径及左心室射血分数差异均无统计学意义（P>0.05）。尿毒症组T1、Tm、Tm%均显著低于对照组（P均<0.01）。T1、Tm、Tm%与右心室纵向应变均呈高度正相关（r=0.79、0.87、0.92,P均<0.01）。结论 应用2D-STI测定的TAD与右心室壁纵向应变存在良好相关性,有望成为评价右心室收缩功能的新方法。     

应用三维斑点追踪技术评价2型糖尿病患者左心室收缩功能

目的 应用三维斑点追踪技术(3D-STE)检测2型糖尿病(T2DM)患者左心室收缩功能。 方法 收集T2DM患者55例,分为单纯糖尿病组31例和糖尿病合并微血管病变组24例;另选择健康人31名作为对照组。常规采集各切面图像和左心室全容积图像,将全容积图像输入TomTec 4D LV analysis软件,计算16节段心肌三维应变(3DS)、纵向应变(LS)、圆周应变(CS)值,并与左心室射血分数(LVEF)行相关性分析。 结果 与对照组比较,单纯糖尿病组和糖尿病合并微血管病变组中间部和心尖部的前间隔、侧壁,基底部和中间部后壁,心尖部下壁的3DS均显著减低(P均<0.05);中间部前间隔、前壁、后壁,心尖部后间隔 LS均减低(P均<0.05);基底部、中间部及心尖部侧壁,基底部和中间部后壁CS明显减低(P均<0.05);3DS与LVEF呈正相关(r=0.75,P<0.01)。 结论 3D-STE对评价糖尿病左心室动力学具有较高的应用价值;3DS可较CS、LS更全面、客观地评价糖尿病心肌病左心室心肌收缩功能受损情况。     

组织多普勒速度成像定量测量瓣环运动速度评价缩窄性心包炎患者术后心功能改变

目的 应用组织多普勒技术定量评价缩窄性心包炎(CP)患者手术治疗后心脏收缩、舒张功能改变。 方法 选取已确诊为CP且择期接受CP心包剥脱术的患者22例,于手术前及术后1个月分别行超声检查,存储心尖四腔心、心尖两腔心及心尖部左心室长轴切面组织多普勒二维图像,以定量组织多普勒技术分析并记录二尖瓣环各部位及三尖瓣环侧壁收缩期及舒张期峰值运动速度(S'、E'),分别计算各个节段S'、E'及三尖瓣环的平均速度作为二尖瓣环的总体运动速度。 结果 CP患者术后1个月左心室变大(P<0.001),左心房(P=0.011)及右心房(P=0.004)呈不同程度缩小,左心室射血分数增高(P=0.021);三尖瓣环、二尖瓣环左心室侧壁及室间隔S'、E'均有不同程度减低(P均<0.05),三尖瓣环、二尖瓣环S'、E'峰亦有不同程度减低(P均<0.01)。 结论 CP患者术后左心室射血分数增加,心脏各腔室发生趋于正常的重构;术后短期内切除心包瓣环部位S'及E'较术前减低,表明左心室壁纵向运动速度减低。     

Determination of creatine kinase isoenzyme MB activity in serum using immunological inhibition of creatine kinase M subunit activity. Activity kinetics and diagnostic significance in myocardial infarction.

This is a new method for the determination of creatine kinase isoenzyme MB activity in serum. The method uses direct activity measurement of creatine kinase B subunit activity after blocking of CK-M subunit activity by inhibiting antibodies. The test takes no longer than 15 min. The method yields an intra-serial C.V. of 2.0-12.9%, and a C.V. from day to day of 5.5%. The detection limit is 3.4 U/l creatine kinase MB. In the 95 cases with proven myocardial infarction several types of creatine kinase MB activity kinetics could be determined. The percentage of creatine kinase MB of peak CK-total is 6-25%, with a mean of 11.1%. The amount of creatine kinase MB with respect to total CK activity after reinfarction is higher than the amount after initial infarction.     

Dissociable correlates of two classes of retrieval processing in prefrontal cortex

Although substantial evidence suggests that the prefrontal cortex (PFC) implements processes that are critical for accurate episodic memory judgments, the specific roles of different PFC subregions remain unclear. Here, we used event-related functional magnetic resonance imaging to distinguish between prefrontal activity related to operations that (1) influence processing of retrieval cues based on current task demands, or (2) are involved in monitoring the outputs of retrieval. Fourteen participants studied auditory words spoken by a male or female speaker and completed memory tests in which the stimuli were unstudied foil words and studied words spoken by either the same speaker at study, or the alternate speaker. On "general" test trials, participants were to determine whether each word was studied, regardless of the voice of the speaker, whereas on "specific" test trials, participants were to additionally distinguish between studied words that were spoken in the same voice or a different voice at study. Thus, on specific test trials, participants were explicitly required to attend to voice information in order to evaluate each test item. Anterior (right BA 10), dorsolateral prefrontal (right BA 46), and inferior frontal (bilateral BA 47/12) regions were more active during specific than during general trials. Activation in anterior and dorsolateral PFC was enhanced during specific test trials even in response to unstudied items, suggesting that activation in these regions was related to the differential processing of retrieval cues in the two tasks. In contrast, differences between specific and general test trials in inferior frontal regions (bilateral BA 47/12) were seen only for studied items, suggesting a role for these regions in post-retrieval monitoring processes. Results from this study are consistent with the idea that different PFC subregions implement distinct, but complementary processes that collectively support accurate episodic memory judgments.     

俯卧位通气对高海拔地区肺复张治疗无效急性呼吸窘迫综合征患者氧合的影响

目的 探讨俯卧位通气对高海拔地区肺复张术(RM)治疗无效急性呼吸窘迫综合征(ARDS)患者的治疗作用.方法 从海拔2260m的地区医院筛选RM治疗无效的41例ARDS患者[平均氧合指数( PaO2/FiO2)较RM前升高＜20％视为RM无效],依不同病因分为肺内源性ARDS组(ARDSp组)和肺外源性ARDS组(ARDSexp组),每组再按信封法随机分为俯卧位组和仰卧位组,即ARDSp俯卧位组(11例)、ARDSp仰卧位组(9例)、ARDSexp俯卧位组(10例)、ARDSexp仰卧位组(11例).在通气前及通气1、2、3、4h监测动脉血氧分压( PaO2)、PaO2/FiO2、静态顺应性(Cst)、气道阻力(Raw)的变化.结果 通气lh时,ARDSexp俯卧位组PaO2/FiO2( mm Hg,l mm Hg=0.133 kPa)即较通气前显著升高(157.4±40.6比129.3±48.7,P＜0.05),并随通气时间延长呈持续增高趋势,4h达峰值(219.1 ±41.1);且ARDSexp俯卧位组通气3h内PaO2/FiO2较其他3组显著增高,另3组间则差异无统计学意义.ARDSp俯卧位组、ARDSexp俯卧位组通气4h时PaO2/FiO2均较相应仰卧位组显著增高(208.8±39.7比127.4±47.1,219.1±41.1比124.9±50.8,均P＜0.05).4组通气前后Cst无显著改变,各组间差异也无统计学意义.ARDSp俯卧位组通气4h时Raw(cmH2O·L-1·s-1)较通气前显著降低(6.8±1.7比10.7±1.8,P＜0.05),且明显低于其他3组;其他3组各时间点Raw组内及组间比较差异均无统计学意义.结论 俯卧位通气作为ARDS机械通气重要策略之一,可以改善RM无效高原ARDS患者的氧合,为抢救患者赢得宝贵的时间.     

Digital imaging among medical facilities

The Department of Veterans Affairs (VA) in the USA operates a network of 172 medical centres which all utilize a hospital information system (HIS) which has been developed and is currently maintained by the VA. During the past several years, an image management and communication module has been developed, installed and clinically utilized at the Washington DC and Maryland VA Medical Centres. This image management and communication system, referred to as the decentralized hospital computer program (DHCP) imaging system, is fully integrated with a commercial picture archiving and communication system (PACS). The system is utilized to capture, archive, and display all images generated within the hospital including radiology, nuclear medicine, pathology, endoscopy, bronchoscopy, and dermatology, intraoperative photographs, ECG data, and a limited number of paper documents. The ultimate goal of the project is to have all patient text and image data available at any clinical workstation to any authorized user anywhere within the network of medical centres. Clinical requirements for an imaging workstation include ease of use, rapid and reliable access to the complete set of patient information, and images which are of acceptable quality to meet the requirements of the user and the subspecialty. Patient confidentiality and data security must be safeguarded at all times. Integration of the images with the remainder of the patient's database was found to be critical to the success of the project. The experience at the Washington and Maryland facilities suggests that an imaging system that is successfully integrated with a hospital information system can provide substantial clinical and economic benefits both within and among medical centres. Clinical acceptance and utilization of the system has been excellent, particularly in diagnostic radiology where DHCP Imaging has been interfaced to a commercial PAC system. Based upon this initial experience, the VA has begun to deploy the system throughout its large network of medical centres.     

Myocardial elastography at both high temporal and spatial resolution for the detection of infarcts

Myocardial elastography is a novel method for noninvasively assessing regional myocardial function, with the advantages of high spatial and temporal resolution and high signal-to-noise ratio (SNR). In this paper, in-vivo experiments were performed in anesthetized normal and infarcted mice (one day after left anterior descending coronary artery [LAD] ligation) using a high-resolution (30 MHz) ultrasound system (Vevo 770, VisualSonics Inc., Toronto, ON, Canada). Radiofrequency (RF) signals of the left ventricle (LV) in longitudinal (long-axis) view and the associated electrocardiogram (ECG) were simultaneously acquired. Using a retrospective ECG gating technique, 2-D full field-of-view RF frames were acquired at an extremely high frame rate (8 kHz) that resulted in high-quality incremental displacement and strain estimation of the myocardium. The incremental results were further accumulated to obtain the cumulative displacements and strains. Two-dimensional and M-mode displacement images and strain images (elastograms), as well as displacement and strain profiles as a function of time, were compared between normal and infarcted mice. Incremental results clearly depicted cardiac events including LV contraction, LV relaxation and isovolumetric phases in both normal and infarcted mice, and also evidently indicated reduced motion and deformation in the infarcted myocardium. The elastograms indicated that the infarcted regions underwent thinning during systole rather than thickening, as in the normal case. The cumulative elastograms were found to have higher elastographic SNR (SNR(e)) than the incremental elastograms (e.g., 10.6 vs. 4.7 in a normal myocardium, and 6.0 vs. 2.4 in an infarcted myocardium). Finally, preliminary statistical results from nine normal (m = 9) and seven infarcted (n = 7) mice indicated the capability of the cumulative strain in differentiating infracted from normal myocardia. In conclusion, myocardial elastography could provide regional strain information at simultaneously high temporal (>/=0.125 ms) and spatial ( approximately 55 microm) resolution as well as high precision ( approximately 0.05 microm displacement). This technique was thus capable of accurately characterizing normal myocardial function throughout an entire cardiac cycle, at the same high resolution, and detecting and localizing myocardial infarction in vivo.     

手转胎头术失败的原因与分娩结局临床分析

目的 探讨手转胎头术失败的原因与分娩结局.方法 选择2008年1月至2010年12月于我院住院分娩的持续性枕横位、枕后位产妇198例,根据行手转胎头术后结果分为成功组126例、失败组72例.比较两组分娩结局,对比分析失败原因.结果 失败组胎儿体质量≥3500 g的发生率[76.4％(55/72)]明显高于成功组[31.7％(40/126)],差异有统计学意义(x2=30.177,P=0.001)、失败组宫缩乏力发生率[58.3％(42/72)]高于成功组[38.1％ (48/126)],差异有统计学意义(x2=7.569,P=0.006)、失败组骨盆临界或轻度狭窄发生率[38.9％ (28/72)]高于成功组[23.8％(30/126)],差异有统计学意义(x2 =5.030,P=0.002)、失败组手转胎头时机不当(宫口开大＜6 cm、胎头位于坐骨棘上及宫口开大8～10 cm、胎头位于坐骨棘下≥2 cm)发生率[61.1％(44/72)]高于成功组[38.9％(49/126)],差异有统计学意义(x2=9.084,P=0.003).失败组母儿并发症(产后出血、产褥病率、胎儿窘迫、新生儿窒息)发生率高于成功组(x2 =9.586,P=0.002、x2=9.334,P=0.002、x2=5.910,P=0.015、x2=5.240,P=0.022)、失败组剖宫产发生率[72.2％(52/72)]明显高于成功组[34.1 ％(43/126),x2=26.641,P=0.001)].结论 手转胎头术能使难产变顺产,降低剖宫产率,减少母儿并发症,但须积极预防、处理导致手转胎头术失败的原因,对矫正失败后继续矫正及试产应慎重.