组织多普勒及应变率成像技术对二尖瓣狭窄患者右心室收缩功能的评价

目的：应用组织多普勒（ TDI）及应变率成像（ SRI）技术评价无右心衰症状的二尖瓣狭窄（ MS）患者的右心室（ RV）整体及局部心肌收缩功能。方法单纯性MS患者40例,健康对照组20例。测量左心房前后径（ LAD）、肺动脉收缩压（ PASP）,描记二尖瓣口面积（ MVA）,M型超声测量三尖瓣环的收缩期位移（ TAPSE）,计算右室面积变化率（ RVFAC）。应用TDI技术测量三尖瓣环收缩期速度（ Tric-s）,等容收缩期速度（ IVV）,等容收缩期加速度（IVA）。 SRI测量右心室游离壁（RVFW）及室间隔的收缩期应变（S）及应变率（SR）,RVFW及室间隔的S及SR的均值作为RV整体长轴的S和SR。并将S和SR与PASP进行相关性分析。结果与对照组相比,MS组的LAD及PASP明显增高（P＜0．01）。 MS组的TAPSE 及Tri -s、IVV、IVA明显低于对照组（P＜0．01或 P＜0．05）。 RV长轴整体S及SR,RVFW基底段及中段的S及SR,室间隔基底段S明显低于对照组（P＜0．05或P＜0．01）,室间隔中段S及室间隔各段SR在两组间无差别。 RV长轴整体S、SR均与PASP呈负相关,相关系数分别为r＝-0．71,r＝-0．59（P均＜0．05）。结论应用TDI及SRI技术可以早期发现MS患者RV整体及局部功能的受损情况。     

Optimization of atrioventricular delay by surface electrocardiography during dual chamber pacing

During dual chamber pacing, both atrial and ventricular leads are routinely positioned at the right appendage and right ventricular apex. Alterations in cardiac electromechanical direction and sequence may have an impact on left atrial and ventricular contraction and filling, leading to reduction in left ventricular (LV) pumping function due to abnormal atrioventricular (AV) delay.1 To achieve adequate cardiac output and haemody- namic advantages of the heart in dual chamber pacing,2 optimal …     

Assessment of cardiac function and synchronicity in subjects with isolated bundle branch block using Doppler imaging

Background Using tissue Doppler imaging and conventional echocardiographic technique, we examined the cardiac function and synchronicity in individuals with isolated right bundle branch block （RBBB） or left bundle branch block （LBBB） and assessed the relationship between QRS duration and synchronicity.     

Electrical remodeling of membrane ionic channels of hypertrophied ventricular myocytes from spontaneously hypertensive rats

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DTI测量二尖瓣环等容收缩期运动速度评价心肌梗死患者左室整体收缩功能

目的 应用多普勒组织成像（DTI）技术测量二尖瓣环等容收缩期速度波（IVC）的选系列指标，探讨其评价心肌梗死患者左心室整体收缩功能的价值。方法 应用DTI技术检测30例正常人和20例陈旧性心肌梗死患者二尖瓣环心肌长轴等容收缩期速度波的系列指标，取样容积分别置于心尖四腔切面、心尖两腔切面上的二尖瓣环间隔壁、侧壁、前壁和下壁，测量等容收缩期正向波的峰值速度（VIVC1）、负向波的峰值速度（VIVC2），计算正负向峰值速度的差值（DIVC）及各点均值。结果陈旧性心肌梗死患者各点的VIVC1均较对照组减小（P〈0．05），VIVC2较对照组增大（P〈0．05），以前壁、间隔壁为著。陈旧性心肌梗死患者二尖瓣环各点IVC1的均值（VIVC1—M）、DIVC的均值（DIVC—M）与应用Simpson法所测左室射血分数有良好的相关性（r=0．68，P〈0．05；r=0．75，P〈0．01）。结论 DTI技术所测二尖瓣环等容收缩期的系列速度指标可作为评价陈旧性心肌梗死患者左室整体收缩功能的新指标。     

Value of Quantitative Tissue Velocity Imaging in the Detection of Regional Myocardial Function in Dogs with Acute Subendocardial Ischemia

This study evaluated the application of quantitative tissue velocity imaging （QTVI） in assessing regional myocardial systolic and diastolic functions in dogs with acute subendocardial ischemia. Animal models of subendocardial ischemia were established by injecting microspheres （about 300 μm in diameter） into the proximal end of left circumflex coronary artery in 11 hybrid dogs through cannulation. Before and after embolization, two-dimensional echocardiography, QTVI and real-time myocardial contrast echocardiography （RT-MCE） via intravenous infusion of self-made microbubbles,were performed, respectively. The systolic segmental wall thickening and subendocardial myocardial longitudinal velocities of risk segments before and after embolization were compared by using paired t analysis. The regional myocardial video intensity versus contrast time could be fitted to an exponential function： y=A·（1-exp-β·t）, in which the product of A and β provides a measure of myocardial blood flow. RT-MCE showed that subendocardial normalized A·β was decreased markedly from 0.99±0.19 to 0.35±0.11 （P〈0.05） in 28 left ventricular （LV） myocardial segments after embolization, including 6 basal and 9 middle segments of lateral wall （LW）, 8 middle segments of posterior wall （PW） and 5 middle segments of inferior wall （IW）. However, there was no statistically significant difference in subepicardial layer before and after embolization. Accordingly, the ratio of A·β of subendocardial myocardium to subepicardial myocardium in these segments was significantly decreased from 1.10±0.10 to 0.31±0.07 （P〈0.05）. Although the systolic wall thickening did not change 5 min after the embolization in these ischemic segments （29%±3% vs 31%±5%, P〉0.05）, the longitudinal peak systolic velocities （Vs） and early-diastolic peak velocities （Ve） recorded by QTVI were declined significantly （P〈0.05）. Moreover, the subendocardial velocity curves during isovolumic relaxation predominant     

应用组织多普勒技术评价正常成人心房机械功能

目的:探讨应用组织多普勒成像(tissue Doppler imaging,TDI)技术检测正常人心房局部心肌舒缩功能的运动特性。方法:对128例健康志愿者行彩色多普勒超声心动图检查,取标准心尖四腔切面,采集左心房侧壁、房间隔和右心房壁基底段及中段心肌组织的DTI二维图像,定量分析上述各节段心房肌运动的速度曲线(quantitative tissue velocity imaging,QTVI)、组织位移(displacement,Ds)及心房壁收缩的起始时间与达峰时间。结果:(1)心房心肌的峰值速度,相同节段不同房壁与不同节段相同房壁间差异有显著统计学意义,相同节段右心房壁>左心房侧壁>房间隔,各房壁自身基底段>中段(P<0.05或P<0.01),心室收缩期峰值速度(VS)、舒张早期峰值速度(VE)与年龄呈负相关(分别为r=-0.38、r=-0.72,P<0.01),舒张晚期峰值速度(VA)与年龄呈正相关(r=0.36,P<0.01)。(2)心房心肌收缩的起始时间,右心房壁<房间隔<左心房侧壁(P<0.01);达峰时间,房间隔<左心房侧壁及右心房壁(P<0.01),左心房侧壁与右心房壁间无显著差异。(3)Ds在相同节段不同房壁与不同节段相同房壁间差异有统计学意义,右心房壁>左心房侧壁及房间隔,基底段>中段(P<0.01),与年龄呈负相关(r=-0.33,P<0.01)。(4)所有数据性别间比较差异无统计学意义。结论:正常成人心房心肌组织机械运动速度和位移由房室瓣环处向心房顶部递减;右心房的运动速度和位移大于左心房,运动起始时间早于左心房。TDI技术可定量、简便、无创评价心房局部的运动特性。     

Imbalance of endogenous homocysteine and hydrogen sulfide metabolic pathway in essential hypertensive children

Background  Hypertension is a common disease of the cardiovascular system. So far, the pathogenesis of primary hypertension remains unclear. The elaboration of its pathogenesis is an important topic in the field which calls for urgent resolution. The aim of this study was to probe into the metabolic imbalance of homocysteine (Hcy) and hydrogen sulfide (H₂S) in children with essential hypertension, and its significance in the pathogenesis of essential hypertension.
Methods  Twenty-five children with essential hypertension and 30 healthy children with normal blood pressure were enrolled in the study. The medical history was investigated and a physical examination was conducted on the subjects. Plasma Hcy content was examined by fluorescence polarization immunoassay (FPIA). The plasma H₂S level was detected by a modified method with a sulfide electrode. Data were presented as mean±standard deviation. The t test was applied to the mean values of both groups. Pearson linear correlation analysis was applied to the plasma Hcy and H₂S as well as to the systolic pressure against the plasma H₂S/Hcy ratio.
Results  Plasma Hcy, an intermittent metabolite of the endogenous methionine pathway, was markedly increased but plasma H₂S, a final product of this pathway was significantly decreased in hypertensive cases when compared with normal subjects ((Hcy: (12.68±9.69) µmol/L vs (6.62±4.79) µmol/L (t=2.996, P<0.01); H₂S: (51.93±6.01) µmol/L vs (65.70±5.50) µmol/L) (t=-8.670, P<0.01)). The ratio of plasma H₂S/Hcy in children with hypertension was 5.83±2.91, while that of the control group was 11.60±3.30, and the difference is significant with a t=-6.610 and P<0.01. A negative correlation existed between plasma Hcy and H₂S concentrations, r=-0.379, P<0.05. And a negative correlation was found between systolic blood pressure and the plasma H₂S/Hcy ratio, r=-0.687, P<0.05.
Conclusion  There was a metabolic imbalance of homocysteine and hydrogen sulfide in essential hypertensive children.

     

Survey: Chinese children get inadequate sleep

Background The identification of vulnerable plaques before rupture is an important clinical goal. The purpose of the present study was to assess the difference in plaque composition among patients with acute coronary syndrome （ACS） and stable coronary artery disease （SCAD） by intravascular ultrasound virtual histologic analysis. Methods One hundred and thirty-nine patients were divided into ACS group and SCAD group according to clinical presentation. A total of 229 de novo lesions with 〉50% stenosis in native coronary arteries with diameters 〉2.5 mm were studied with intravascular ultrasonography. Geometric and compositional data were obtained using intravascular ultrasound virtual histology software. Results There were no significant differences in overall lesions for fibrous （（52.0±11.9）% vs （54.3±8.5）%, P〉0.05）, fibrolipidic （（12.3±10.1）% vs （13.8±9.5）%,P〈0.05）, calcium （（14.0±9.1）% vs （19.3±13.1）%, P〉0.05）, or necrotic core （（22.0±11.1）% vs （19.7±5.4）%, P〉0.05） percentages in ACS and SCAD patients, respectively. There were also no significant differences in culprit lesions for fibrous （（46.4±12.0）% vs （53.6±8.8）%, P〉0.05）, fibrolipidic （（9.1±9.0）% vs （12.9±9.7）%, P〉0.05）, calcium （（16.6±9.7）% vs （21.8±26.3）%, P〉0.05）, or necrotic core （（28.0±12.6）% vs （20.6±5.2）%, P〉0.05） percentages in ACS and SCAD patients, respectively. High density lipoprotein-cholesterol levels 〉1.04 mmol/L were associated with more fibrolipidic （（14.5±10.4）% vs （7.1±6.5）%, P〈0.05） and less necrotic core （（20.6±9.7）% vs （27.9±12.6）%,P〈0.05） percentages in the cohort with ACS. Conclusions In this study, coronary plaque composition assessed by intravascular ultrasound virtual histologic analysis was not significantly different between ACS and SCAD patients. The anatomic relationship of the specific plaque components to the lumen of the vessel was more important than th     

Decreased small arterial compliance with increased serum vascular endothelial growth factor-A and circulating endothelial progenitor cell in dilated cardiomyopathy

Background Evidence showed that both myocardium and blood vessels were damaged in dilated cardiomyopathy （DCM）. However, the changes in arterial compliance, serum cytokines and circulating endothelial progenitor cells （EPC）, and their correlations remain unknown.
Methods Sixty-five DCM patients and 49 healthy volunteers were studied. Both large artery compliance （C1） and small artery compliance （C2） were measured with the CVProfUor DO-2020. Quantitative enzyme-linked immunosorbent assays （ELISAs） were used to measure the levels of vascular endothelial growth factor-A （VEGF-A） and VEGF receptor 2 （VEGF-R2）. Circulating EPC was assessed by EPC colony-forming assays and flow cytometry （CD133^＋/CD34^＋cells）. Phagocytized Dil-acLDL and binded FITC-UEA-I were used to analyze endothelial lineage marker expression by immunofluorescence.
Results Although C2 was markedly lower in DCM patients than in control group （（3.8±1.8） ml/mmHg × 100 vs （5.0±2.2） ml/mmHg × 100, P〈0.0001）, there was no statistically significant difference in C1 between the two groups （P〉0.05）. Levels of VEGF-A, the numbers of colony-forming units （CFU） and the fractions of EPC were obviously higher in DCM patients than in control group （（127.6±139.5） pg/ml vs （58.8±42.9） pg/ml, P〈0.0001; （2.5±1.5）% vs （0.5±0.3）%, P〈0.05; 23.5±12.8 vs 10.8±7.4, P〈0.01, respectively） and however, there was no significant difference in VEGF-R2 between two groups （P〉0.05）. LgVEGF-A was positively correlated with the number of EPC-CFU （r=-0.435; P〈0.05） and inversely correlated with C2 （r=-0.543; P〈0.001） in DCM patients. Conclusions The reduction of C2, a sensitive marker reflecting endothelial dysfunction, was observed in DCM patients and closely related to the increase in serum VEGF-A.     

Predictors of left atrial appendage stunning after electrical cardioversion of non-valvular atrial fibrillation

Atrialfibrillation (AF)isthemostcommon persistentarrhythmia,leadingtoembolismsfrequently 1Restorationofsinusrhythmimprovescardiacfunctionalcapacity,alleviatespalpitation ,andreducestheriskofembolisms Direct currentcardioversionhastheadvantageofimmediaterestorationofsinusrhythm ,butitisfrequentlyassociatedwithtransientatrialmechanicaldysfunction ,i e “atrialstunning” ,whichmayincreasetheriskofsubsequentthromboembolicevents 2 　Withtheadventoftransesophagealechocardiography (TEE) ,leftatrial…     

Efficacy of adaptive servoventilation in patients with congestive heart failure and Cheyne-Stokes respiration

Approximately 40% of patients with congestive heart failure (CHF) experience Cheyne-Stokesrespiration (CSR). Comparison between CHF patients with and without CSR has demonstrated that even though the left ventricle ejection fraction (LVEF) was similar at the beginning, those with CSR usually had a worse prognosis than those without CSR. The poor prognosis is associated with sleeping disordered breathing (SDB), intermittent hypoxemia and lower survival in CHF patients with CSR.1-4 …     

Inhibitory effect of tea polyphenols on renal cell apoptosis in rat test subjects suffering from cyclosporine-induced chronic nephrotoxicity

Objective To investigate the inhibitory effect of tea polyphenols on renal cell apoptosis in rat test subjects suffering from cyclosporine A (CsA)-induced chronic nephrotoxicity.Methods Four groups of rats with CsA-induced chronic nephrotoxicity were respectively treated with vehicle olive oil, tea polyphenols, CsA and tea polyphenols plus CsA. At the end of the 28th day of treatment, 24 hours urine and blood samples were obtained, and the animals were then sacrificed. The serum and urine samples were analysed for creatinine clearance, and kidney tissue was used for pathologic analysis of renal tubular injury and interstitial fibrosis. The TUNEL assay, apoptosis-related enzyme caspase-3 mRNA detected by RT-PCR, and its enzymatic activity were analysed for the possible detections of cell apoptosis.Results CsA-treated rats displayed increased apoptosis of the tubular and interstitial cells, in comparison with vehicle-treated controls (18. 3±4. 6 vs 4. 8±1.3 cells/mm2, P < 0. 05 ) . In comparision with a     

dl-3-n-butylphthalide reduces brain damage in mice with closed head injury

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高频生物显微镜结合组织多普勒评价扩张型心肌病小鼠心功能的可行性

目的 应用扩张型心肌病（DCM）小鼠模型探讨组织多普勒显像（TDI）评价早期心肌功能障碍的可行性。方法 应用Vevo 770超声生物显微镜和30~40MHz高频探头,分别在小鼠生后第3个月（G1组,n=12）、第6个月（G2组,n=11）和第9个月（G3组,n=10）对携带ZASP4突变的33只DCM小鼠进行M型、二维及TDI超声心动图检查。以M型和二维超声评价整体心脏功能以获取短轴缩短率（FS）和射血分数（EF）。TDI的取样容积置于左心室后壁,并将其分为基底段、中间段和心尖段以获取收缩和舒张峰值速度。结果 M型和二维超声测量G1、G2组的EF与FS之间均无统计学差异(P＞0.05),而G3组则明显降低(P<0.01)。以TDI测量的G2组基底段和中间段收缩峰值速度明显低于G1组［(28.6±4.3) vs （45.8±12.0）mm/s,（26.3±5.3）vs（38.6±12.6）mm/s,P<0.01］;舒张峰值速度也低于G1组［(32.3±6.3) vs (53.3±12.6)mm/s,(27.3±7.2) vs (41.9±12.0)mm/s,P<0.01)］,G3组基底段和中间段的峰值速度相比,G1和G2组减少更为明显(P<0.01)。结论 利用高频显微镜进行TDI评测是可行的;并且TDI检测DCM小鼠模型的早期心功能障碍更敏感。     

Myocardial bridging detection by non-invasive multislice spiral computed tomography: comparison with intravascular ultrasound

Background Invasive intravascular ultrasound （IVUS） is current diagnostic standard for myocardial bridging （MB）. Non-invasive multislice computerized tomography coronary angiography （MSCT） technique has provided a good anatomical view of the tunnel artery now. Methods A total of 51 consecutive patients with atypical or typical angina scheduled for IVUS were enrolled in this study and MSCT was performed 7 days before IVUS. Coronary imaging was quantified using IVUS and MSCT. Four main vessels （left main artery （LMA）, left anterior descending （LAD）, left circumflex （LCX）, right coronary artery （RCA）） were examined. Results Forty-one out of 51 （80%） patients received metaprolol （25 mg） before the MSCT scan and 25 of them were current beta-blocker users. The mean heart rate was （64_＋3） beats per minute. A total of 51 patients underwent IVUS examination （30 with MB and 21 without MB） were chosen for this study. Twenty-eight out of 30 MB cases were correctly diagnosed by MSCT and 2 patients with MB were not detected. Comparison with IVUS, the sensitivity of detection by MSCT was 93%, specificity was 100%. The lumen diameter of the tunnel artery derived from MSCT and IVUS significantly decreased from （2.9±0.3） mm to （2.4±0.4） mm （P〈0.001） and from （3.3±0.3） mm to （2.6±0.5） mm （P〈0.001）, respectively. Minimal and maximal diameters of MB derived from MSCT were significantly smaller than those from IVUS （（2.4±0.4） mm vs （2.6±0.5） mm, P〈0.05 and （2.9±0.3） mm vs （3.3±0.3） mm, P〈0.05）, respectively. Conclusions MSCT offers a reliable non-invasive method for MB in LAD and atherosclerosis diagnosis with diagnostic accuracy comparable with invasive IVUS.     

Tei指数评价艾滋病患者右心功能的组织多普勒超声心动图研究

目的:应用组织多普勒成像技术(tissue doppler imaging,TDI)测量三尖瓣环运动速度及时间间期指标评价AIDS患者右心功能,探讨组织多普勒评价AIDS患者右心功能的临床价值。方法:对72例AIDS患者行超声心动图检查,采集三尖瓣环瓣叶附着点处前、后、侧壁3个位点的TDI频谱,测量各位点的收缩期峰值速度(Vs)、舒张早期峰值速度(Ve)、舒张晚期峰值速度(Va),计算右心平均Vs、Ve、Va。同时测量三尖瓣环瓣叶附着点处侧壁位点时间间期指标(A线、B线),计算Tei指数。并与健康对照组进行对照分析。结果:病例组三尖瓣环各位点Vs、Ve、Va及Vs[(11.33±1.91)cm/s,(12.74±2.09)cm/s]、Ve[(11.69±2.41)cm/s,(15.17±3.05)cm/s]、Va[(10.61±2.45)cm/s,(12.71±3.18)cm/s]较对照组明显降低(P<0.05),右心Tei指数与对照组相比明显升高(0.41±0.11,0.30±0.16,P<0.05),差异具统计学意义。结论:AIDS患者可发生右心功能障碍。     

Extracellular domain of kinase domain region mediated by adeno-associated virus inhibits growth and angiogenesis of bladder cancer in Balb-c mice

目的：从原代培养的人脐静脉血管内皮细胞（HUVEC）提取细胞总RNA,采用逆转录PCR(RT-PCR)方法得到VEGF受体KDR全长胞外区cDNA片段,检验其体内抗肿瘤血管生成的作用。方法：将获得的受体基因克隆到AAV基因治疗载体pSNAV中,得到重组质粒pSNAV/KDR。重组质粒转染BHK细胞,加入辅助病毒后,得到表达目的蛋白的重组AAV。重组AAV表达的KDR具有与VEGF结合的活性,重组AAV感染膀胱癌EJ细胞,皮下注射Balb-c裸鼠。Ⅷ因子免疫组化染色进行微血管密度测定。结果：重组AAV感染有膀胱癌EJ细胞形成的肿瘤血管化程度明显低于对照组。结论：重组AAV介导的KDR胞外区基因可有效的抑制裸鼠人膀胱癌组织的新生血管生成。     

Assessment of Right Ventricular Free Wall Longitudinal Myocardial Deformation Using Speckle Tracking Imaging in Normal Subjects

To assess fight ventficular free wall longitudinal myocardium deformation and examine the changes with normal age by speckle tracking imaging （STI）, myocardial systolic peak strain （ε）, systolic peak strain rate （SRs）, early diastolic peak strain rate （SRe）, late diastolic peak strain rate （SRa）, the ratio of SRe/SRa were measured in the basal, middle and apical segments of right ventficular free wall in 75 healthy volunteers （age range： 21-71 y） by STI from the apical 4-chamber view. RV longitudinal strain and strain rate were highest in the basal segment of the free wall. Older subjects had lower early diastolic strain rate （SRe） than younger subjects, but they had higher late diastolic strain rate （SRa）. A negative correlation between age and the ratio of SRe/SRa was found in all RV free wall segments （r=-4）.466 - -0.614, P〈0.01）. It is concluded that RV diastolic strain rate changes with age and STI can be used for the study of RV myocardial deformation.