Effect of pericardium on regional myocardial systolic function in acute ischemia.

To know whether or not the pericardium affects regional myocardial systolic function in acute ischemia, we measured ischemic and non-ischemic segment lengths of the left ventricle using ultrasonic crystals in 10 open-chest dogs with the pericardium preserved. When the left ventricular pressure and segment lengths were stable after left circumflex coronary occlusion, we opened the pericardium widely. After coronary occlusion, end-diastolic length (EDL) in ischemic and non-ischemic segments increased, and the ischemic segment showed paradoxical systolic expansion while the non-ischemic segment increased its active shortening. After pericardiectomy, heart rate, left ventricular systolic pressure, and peak positive and negative dP/dt did not change. EDL in ischemic and non-ischemic segments further increased from 12.02 +/- 0.18 to 12.50 +/- 0.16 mm (mean +/- S.E., p less than 0.01) and from 11.12 +/- 0.20 to 11.45 +/- 0.18 mm (p less than 0.05), respectively, despite the concomitant fall in left ventricular end-diastolic pressure (LVEDP) from 12.4 +/- 0.6 to 10.6 +/- 0.8 mmHg (p less than 0.01). End-systolic length in ischemic and non-ischemic segments also increased from 12.37 +/- 0.25 to 12.70 +/- 0.20 mm (p less than 0.05) and from 8.50 +/- 0.13 to 8.74 +/- 0.13 mm (p less than 0.01), respectively, although the left ventricular end-systolic pressure did not change. Maximum expanded systolic length of the ischemic segment also increased from 12.99 +/- 0.20 to 13.42 +/- 0.16 mm (p less than 0.01). These results indicate that, in acute ischemia, the pericardium inhibits paradoxical systolic expansion of the ischemic region and increase in end-systolic length of non-ischemic segment. Thus, it is concluded that the pericardium modifies the regional myocardial systolic function in acute ischemia, perhaps through the mechanical restraint of the pericardium.     

斑点追踪成像技术对肥厚型心肌病左心室收缩功能的评价

目的 应用斑点追踪成像技术研究正常人及肥厚型心肌病患者的左心室长轴纵向、短轴径向及圆周应变改变规律,探讨其I临床应用价值.方法 获取正常对照组(27例)、非对称型肥厚型心肌病组(20例)标准心尖四腔、三腔、两腔和短轴二尖瓣、乳头肌、心尖水平图像;分别测量和比较肥厚型心肌病组与正常对照组各节段的纵向、径向和圆周的收缩期峰值应变.结果 正常组左室长轴纵向应变在心尖部最大(P＜0.05);短轴径向应变差异无统计学意义;圆周应变在室间隔及前间隔较大其他室壁节段高(P＜0.05).与对照组比较,肥厚型心肌病组,纵向应变平均值降低(P＜0.05);短轴径向及圆周应变平均值降低,但差异无统计学意义(P＞0.05);在室壁肥厚的前间隔、后间隔及与之相邻的前壁、下壁圆周及径向应变降低(P＜0.05).结论 斑点成像技术能够较好的评价肥厚型心肌病左室整体和局部的收缩功能.     

心肌速度分布图评价左室局部收缩功能的初步研究

目的应用组织多普勒心肌速度分布图(myocardial velocity profile,MVP)对左室短轴方向局部收缩功能进行评价。方法应用MVP对15例健康志愿者、15例高血压性左室肥厚患者和11例室间隔非对称性肥厚型心肌病患者的室间隔和左室后壁短轴方向的收缩功能进行评价。结果高血压组的室间隔和左室后壁收缩期心肌速度梯度(myocardialvelocity gradient,MVG)显著低于对照组,具有统计学差异[(1.8±0.3)vs(3.6±0.4),P<0.001和(1.9±0.2)vs(5.1±1.2),P<0.001]。肥厚型心肌病组的室间隔和左室后壁收缩期MVG显著低于对照组,具有统计学差异[(1.2±0.4)vs(3.6±0.4),P<0.0001和(2.4±0.6)vs(5.1±1.2),P<0.001]。MVG的降低以肥厚型心肌病组的室间隔最为显著,肥厚型心肌病组的室间隔收缩期MVG低于高血压组,具有统计学差异[(1.2±0.4)vs(1.8±0.3),P<0.01]。高血压组、肥厚型心肌病组和对照组室间隔的MVP均呈近似线性,但肥厚型心肌病组心肌各点速度分布较对照组和高血压组明显分散。结论高血压性左室肥厚患者和肥厚型心肌病患者左室短轴方向局部收缩功能较正常人减低,MVP能精确地反映心肌短轴上各点在心动周期中的运动速度,并可计算出MVG,可作为一种准确评价左室心肌短轴方向局部收缩功能的新方法。     

Can changes in systolic longitudinal deformation quantify regional myocardial function after an acute infarction? An ultrasonic strain rate and strain study.

OBJECTIVES: The aim of this study was to evaluate the additional value of ultrasonic strain rate and strain to myocardial velocity in the identification and quantification of regional asynergy after an acute myocardial infarction (MI). METHODS: Forty patients (59 +/- 13 years) were investigated 3 +/- 2 days after a first infarction and compared with 14 age-matched controls with normally contracting segments (group A, n = 146). Longitudinal myocardial velocities, strain rate (SR) and strain (epsilon) were postprocessed from basal, mid, and apical segments interrogated using apical views. In a subset of patients with coronary angiograms (n = 24), myocardial segments were divided into 3 groups: normally contracting segments supplied by a normal coronary artery (group B1), normally contracting segments supplied by a diseased coronary artery (group B2), and segments with abnormal motion (group B3). Velocities were decreased in patients with myocardial infarction (MI) (P <.05 vs controls) but failed to accurately differentiate normally from abnormally contracting segments. At the opposite end, systolic SR and epsilon decreased significantly with segmental asynergy severity and could identify infarct-involved segments (group B3) with a sensitivity/specificity of 85% (systolic SR and epsilon cutoff values of -0.8 s(-1) and -13%, respectively). CONCLUSION: Strain rate and strain can better assess segmental dysfunction severity than myocardial velocities alone after an acute MI.     

实时三平面应变率成像评价舒张性心力衰竭患者左心室局部心肌收缩功能

目的：应用实时三平面应变率成像检测舒张性心力衰竭患者左心室局部心肌收缩功能,探讨其临床意义。方法：选取舒张性心力衰竭患者29例、收缩性心力衰竭患者26例和正常人30例,应用实时三平面应变率成像测定左心室各壁基底段和中间段收缩期峰值应变率（SRs）。结果：舒张性心力衰竭组、收缩性心力衰竭组左心室壁各节段SRs均小于正常组相应节段（P＜0.05或P＜0.01）,且正常组、舒张性心力衰竭组、收缩性心力衰竭组各组SRs逐渐减小（P＜0.05或P＜0.01）。结论：舒张性心力衰竭患者存在左心室局部心肌收缩功能异常,实时三平面应变率成像检测左心室局部心肌收缩功能在心力衰竭患者心脏功能评价中具有重要价值。     

定量组织速度成像对急性心肌梗死犬左心室局域收缩功能的实验研究

目的 探讨犬急性心肌梗死后左心室局域心肌等容收缩期及射血期在长轴方向的收缩运动特点.方法 对24只急性心肌梗死犬在定量组织速度成像(QTVI )条件下扫查冠状动脉结扎前、结扎后4 h心尖二腔心、心尖四腔心及心尖五腔心切面,并应用组织速度曲线对梗死前后左心室各节段长轴方向的运动特点进行分析.取样容积分别置于左心室基底部、中部乳头肌水平及心尖部心内膜下,记录等容收缩期最大、最小峰值速度及对应时间,收缩期峰值速度(Vs)及时间,并计算等容收缩期加速度(Aivs)及收缩期加速度(As).结果 急性心肌梗死犬受累节段的Vs、As明显低于正常心肌相应节段(P＜0.05或P＜0.01);梗死节段的Aivs大于正常心肌相应节段,而相邻及相对节段的Aivs则减小(P＜0.05).结论 QTVI能敏感、直观、定量评价左心室局域心肌收缩功能,对急性心肌梗死的早期诊断具有重要潜在价值.     

定量组织速度显像对兔心肌梗死模型左心室收缩功能的评价

目的 探讨定量组织速度显像在定量评价兔心肌梗死模型制备前、后左室收缩功能中的应用价值。方法 30只新西兰白兔分为手术组（20例）及假手术组（10例），手术组结扎兔冠状动脉左室支造成心肌梗死模型，两组兔分别在术前、术后2周进行超声心动图检查，测量室间隔及左室侧壁基底段、中间段、心尖段的收缩期运动速度（Vs）及峰值位移（D）。结果 正常兔心肌组织速度及位移曲线波形规则，Vs值及D值由心底至心尖依次递减；手术组兔心脏心腔增大，EF降低，但与假手术组比较差异无统计学意义（P〉0．05），心肌组织收缩速度及位移曲线失去正常规律性，且室间隔心尖段及左室侧壁中间段、心尖段Vs值及D值降低，与假手术组比较差异有统计学意义（P〈0．05，P〈0．01）。结论 定量组织速度显像可准确评价心肌梗死前、后兔左室局部心肌收缩功能。     

RT-3DE评价心肌梗死患者左室整体与节段收缩功能的研究

实时三维超声心动图(RT-3DE)能确切地反映心室的实际形状,全面反映心脏的各节段运动功能,并能提供左室定量参数[1].而且RT-3DE是实时检测技术,具有良好的时间和空间分辨率[2].本实验旨在探*RT-3DE评价心肌梗死(MI)患者左室整体与节段收缩功能的临床应用价值.     

定量组织速度成像(QTVI)技术对左室收缩功能的研究

目的 用定量组织速度成像(QTVI)技术定量分析生理和病理(心肌缺血)状态下左室心肌收缩运动特征及其临床意义。方法 研究对象为20例心肌梗死患者和20例年龄匹配正常人。采用左室长轴切面，分别显示左心室6个室壁不同节段长轴方向的心肌同步运动曲线。测量左室收缩功能有关参数。结果 与对照组相比，心肌梗死组QTVI可敏感地定量显示出收缩波(S)平均峰值速度显著下降(P＜0.01)；持续时间缩短(P＜0．05)；等容收缩期(IVC)时限延长(P＜0．05)；表明心肌梗死病人心肌收缩功能损害。结论 QTVI技术作为定量定性评价心肌收缩功能的新方法，对无创诊断冠心病具有一定的临床应用价值。     

Intramyocardial analysis of regional systolic and diastolic function in ischemic heart disease with Doppler tissue imaging: role of the different myocardial layers.

BACKGROUND: Preliminary experimental data have shown a nonuniform distribution of myocardial velocities (MVs) across the myocardial wall in normal conditions. However, after ischemic damage to the myocardium, a different pattern of reduction in the myocardial layers has been reported. The aim of this study is to analyze the spatial distribution of MVs and the resultant myocardial velocity gradients (MVGs) during the systolic and diastolic time periods. Doppler tissue imaging (DTI) in color M-mode was used to evaluate 3 different myocardial layers (endocardium, mesocardium, and epicardium) and their changes as a result of ischemia. METHODS: Thirty-two consecutive patients were studied with DTI color M-mode: 18 patients with a history of previous or ongoing myocardial infarction and 14 healthy subjects. Postprocessing of images was accomplished with proprietary software. MV and MVG values of all layers along both systolic and diastolic time were calculated. For temporal analysis, systole was subdivided in 3 equal periods. Early- and late-diastolic times were also identified. RESULTS: In ischemic patients, the mean MV and maximum MV throughout systole decreased significantly in the endocardium and mesocardium, whereas only slightly in the epicardium. The mean MVG was less in ischemic patients (0.66 +/- 0.11 vs 0.23 +/- 0.15, P <.03). Temporal analysis showed a decrease in the maximal MV and MVG in all layers over the 3 systolic periods. This decrease was the more consistent in mesocardium. In diastole, there was a decrease in maximal MV in all layers, being more pronounced in endocardium and mesocardium. Diastolic mean MVG was shown to be different between control and ischemic groups (-0.2 +/- 0.05 vs -0.10 +/- 0.04, P <.06). A significant decrease of the maximal MV in endocardium and mesocardium was reported in the temporal analysis during early diastole. No change was reported in the epicardium. The MVG value also showed a significant decrease (-2.69 +/- 0.29 vs -1.59 +/- 0.89, P <.02). In ischemic patients in late diastole, the maximum MV was increased in all layers of the myocardium, and this increase was observed mainly in the endocardium. An increase in the MVG (-0.78 +/- 0.18 vs -1.47 +/- 0.85, P = NS) was also reported during late diastole. CONCLUSION: There is a nonuniform distribution of velocities in the different myocardial layers under normal conditions. This distribution of velocities undergoes a significant change in patients with ischemic myocardial damage. Intramyocardial wall motion analysis could have clinical applications in both the early detection of ischemia and myocardial viability.     

超声斑点追踪显像技术评价缩窄性心包炎患者左心室局部心肌收缩功能

目的应用超声斑点追踪显像技术(STI)评价缩窄性心包炎(CP)患者左心室局部心肌收缩功能。方法采集26例CP患者左心室心尖位四腔切面、两腔切面、左心室长轴高帧频图像,测量左心室游离壁(前侧壁、下侧壁、前壁、下壁)心内、外膜下心肌各个节段的二维纵向收缩期应变峰值,并与37例正常人比较。结果 (1)CP患者左心室游离壁心外膜下心肌各节段纵向收缩期应变峰值较对照组明显减低(P<0.05),且绝大多数节段P<0.01;(2)CP患者左心室游离壁心内膜下各节段心肌纵向收缩期峰值应变与对照组比较,差异无统计学意义(P>0.05)。结论超声二维应变成像技术能够准确地定量评价CP患者左心室游离壁心内膜下及心外膜下心肌收缩功能,CP患者左心室游离壁心外膜下心肌纵向收缩期峰值应变减低,提示心外膜下心肌收缩功能受损。     

Early changes in left ventricular volume and function are predictors for long-term remodeling in patients with acute transmural myocardial infarction and preserved systolic function.

BACKGROUND: We sought to describe the degree of long-term left ventricular (LV) remodeling after acute transmural myocardial infarction with preserved LV systolic function, and to evaluate whether Doppler echocardiographic parameters in the early phase could predict this process. METHODS: A total of 60 patients without heart failure and with LV ejection fraction > or = 0.40 (mean 0.48 +/- 0.054), were followed up with Doppler echocardiographic examinations at baseline, 3 months, and 1 and 2 years. RESULTS: There was a significant increase in LV end-diastolic volume index of 7% (P =.006) and LV end-systolic volume index of 8% (P =.03), and no change in ejection fraction. This remodeling was confined to 7 patients (12%) with a significant increase in LV end-diastolic volume index above 20 mL/m(2). There was also a significant increase in the deceleration time of both the early mitral filling wave (Delta early mitral filling wave = 58 milliseconds, P <.0005) and the diastolic forward component of pulmonary venous flow (Delta diastolic forward component of pulmonary venous flow = 61 milliseconds, P <.0005), and a shift in filling pattern with increasing prevalence of abnormal relaxation. Changes in end-diastolic volume index were predicted by baseline early mitral filling wave less than 100 milliseconds, but the most powerful predictors of 2-year remodeling were volume changes at 3 months. CONCLUSION: Twelve percent of patients with Q-wave infarction and ejection fraction > or = 0.40 experienced significant LV dilatation at 2 years, and this late remodeling was partly related to baseline filling characteristics.     

New insights into regional systolic and diastolic left ventricular function with tissue Doppler echocardiography: from qualitative analysis to a quantitative approach.

Tissue Doppler echocardiography is a variation of conventional Doppler flow imaging. This modality allows quantification of the Doppler shift within the range of myocardial tissue motion. The velocity at a variety of myocardial sites can be determined and distinguished very rapidly by using Doppler techniques. The velocity of moving tissue can be studied with pulsed wave tissue Doppler sampling, which displays the velocity of a selected myocardial region against time, with high temporal resolution. In addition, the velocities can be calculated with time-velocity maps and displayed as color-encoded velocity maps in either an M-mode or 2-dimensional format. This review will focus on the technical aspects and the different methods of tissue Doppler echocardiography for the analysis of regional systolic and diastolic left ventricular function. Whereas pulsed wave tissue Doppler echocardiography allows measurements of velocities of a selected myocardial region, color tissue Doppler gives the best overview of cardiac dynamics because the entire scanned color data are displayed simultaneously. However, there is an increasing need for objective evaluation of tissue Doppler information. Digital images and postprocessing of the data allow for quantitative off-line analysis, and the different approaches and parameters proposed from different centers are discussed.     

左心室心肌做功效能评价冠状动脉慢血流患者左心室收缩及舒张功能

目的 采用二维斑点追踪技术（STE）检测冠状动脉慢血流（CSF）患者左心室心肌收缩及舒张做功效能（MSP/MDP）。方法 收集经冠状动脉造影诊断为CSF患者50例（CSF组）和一般临床情况与之匹配的无CSF患者45例（对照组）,采用STE检测左心室收缩期峰值整体纵向、径向和圆周应变及舒张早期应变率,计算左心室MSP和MDP,比较2组各参数的差异。结果 CSF组左心室收缩期峰值整体纵向、径向和圆周应变及舒张早期应变率、MSP和MDP均较对照组减低（P均< 0.05）。CSF组冠状动脉平均血流帧数（TFC）与MDP呈负相关（r=-0.23,P=0.04）;冠状动脉受累支数与MDP呈负相关（r=-0.31,P=0.03）。不同冠状动脉受累支数与对照组左心室MDP整体比较差异有统计学意义（P均< 0.05）,且受累2支、3支者MDP较对照组减低（P均<0.05）。结论 CSF患者左心室收缩及舒张功能均减低,且平均TFC越大,冠状动脉受累支数越多,左心室舒张功能减低越明显。利用左心室心肌做功效能可全面评价左心室收缩及舒张功能。     

Changes in systolic and postsystolic wall thickening during acute coronary occlusion and reperfusion in closed-chest pigs: Implications for the assessment of regional myocardial function.

The aim of the study was to characterize the impact of short-lived total coronary occlusions in closed-chest pigs on radial wall thickening within the "at-risk" myocardial segment by using gray-scale M-mode echocardiography. Twelve pigs underwent a series of 20-second total circumflex coronary artery occlusions with an angioplasty balloon. Myocardial thickening/thinning indexes were continuously monitored before ischemia, during ischemia, and on reperfusion by high-resolution M-mode recordings of the posterior wall obtained from parasternal views. The timing of regional events was compared with global systolic time intervals derived from the color Doppler myocardial imaging velocity data. Each occlusion induced a rapid decrease in end-systolic thickening (epsilon(ES)), closely paralleled by an increase in postsystolic thickening in the ischemic segment. After 20 seconds of ischemia, epsilon(ES) decreased by -86% and postsystolic thickening increased by +100%, whereas maximal thickening decreased only by -34% in comparison with preocclusion values. All wall thickening parameters returned to baseline after 15 seconds of reperfusion. During acute total ischemia in a closed-chest animal model, the changes in regional myocardial function were best characterized by the combined analysis of systolic and postsystolic thickening abnormalities and by their respective timings relative to global cardiac events markers.     

实时三维超声心动图评价心肌梗死患者左室收缩功能的研究

目的探讨实时三维超声心动图(RT-3DE)评价心肌梗死患者左室收缩功能的准确性。方法选择临床已确诊的心肌梗死患者25例,分别利用二维超声心动图Simpson’s法、RT-3DE全容积法及心脏磁共振成像(CMRI)测量患者左室舒张末容积(LVEDV)、每搏输出量(SV)、左室射血分数(LVEF),并将三种方法所测参数进行对比分析。结果二维超声心动图Simpson’s法与CMRI所测LVEDV、SV比较差异均有统计学意义(均P0.05),而LVEF差异不明显。RT-3DE与CMRI所测LVEDV、SV、LVEF比较,差异均无统计学意义。Simpson’s法所测LVEDV、SV、LVEF与CMRI所测结果相关(r=0.75、0.75、0.80,P0.05);RT-3DE全容积法所测LVEDV、SV、LVEF与CMRI所测结果高度相关(r=0.89、0.88、0.91,P0.05)。结论 RT-3DE可以准确评价心肌梗死患者的左室收缩功能。     

多普勒组织成像定量分析心肌梗死后左心室局部与整体的舒缩功能

目的　采用多普勒组织成像技术 (DTI)观察心肌梗死后左心室壁及二尖瓣环运动 ,定量分析左心室局部与整体的舒缩功能。方法　 18例健康人 ,3 6例心肌梗死患者均行常规二维超声 (2DE)及DTI检查。采用DTI分析心肌梗死后左室壁及二尖瓣环 4个位点的DTI指标 :峰值收缩速度 (VS)、舒张早期速度 (VE)及二尖瓣环 4个位点平均收缩与舒张速度 (VMS、VME)。结果　与健康人比较 ,心肌梗死患者室壁运动异常节段VS、VE显著降低 (P <0 .0 1) ,心肌梗死节段相对应二尖瓣环位点VS 显著降低 (P <0 .0 1) ,心肌梗死节段与非心肌梗死节段相对应二尖瓣环 4个位点VE 均降低 (P <0 .0 1) ;心肌梗死患者射血分数 (EF)与VMS(r =0 .76,P <0 .0 1)、VME(r =0 .68,P <0 .0 1)呈显著正相关 ;VMS≥ 7.0cm/s预测EF≥ 5 0 %的敏感性、特异性分别为76.0 %、81.8%。结论　DTI可定量分析心肌梗死后左室壁局部与整体的舒缩功能 ,为心肌梗死后合理选择治疗措施及预后判断提供新的定量指标     

组织追踪法评价阿霉素致兔心脏毒性左心室收缩功能影响的研究

目的探讨组织追踪法(TT)评价阿霉素致兔心脏毒性左心室收缩功能的价值。方法42只兔分成4组A组(对照组)10只,注射2mg/kg生理盐水8周;B组10只,每周静脉注射阿霉素2mg/kg,注射2周;C组10只,同样方法给予阿霉素4周;D组12只同样方法给予阿霉素8周。12周后对4组兔心脏用组织追踪法测量二尖瓣瓣环的收缩期位移(Ds);用M型超声心动图测量二尖瓣瓣环收缩期下移距离(Dm);用超声心动图Simpson法测定左室射血分数(LVEF)。结果D组二尖瓣瓣环平均Ds、Dm和、EF明显减低(P<0.01)。C组二尖瓣瓣环平均Ds、Dm明显减低(P<0.01),而EF正常低值(P>0.05)。B组与A组间各参数均无显著性差异(P>0.05)。4组二尖瓣瓣环收缩期平均Ds与Dm显著相关(P<0.04);同时二尖瓣瓣环收缩期平均Ds与LVEF也呈显著相关(P<0.03)。病理结果从B组到D组的心肌损害程度逐渐加重。结论组织追踪法可无创有效地评价阿霉素心脏毒性左室心肌收缩功能的变化。     

超声应变和应变率成像技术评价肥厚型心肌病左室局部心肌的收缩功能

目的分析肥厚型心肌病（HCM）左室局部心肌应变（ε）和应变率（SR）的变化特点,评价HCM患者左室局部心肌的收缩功能。方法收集18例HCM患者和31例正常对照者,采集心尖四腔、二腔、长轴切面的动态图像,取样容积置于左室各节段心内膜下心肌,获取同步的心肌运动曲线、应变曲线和应变率（SR）曲线,测量收缩期最大应变（εsys）、峰值应变（εpeak）和收缩期峰值应变率（SRsys）。结果HCM组有15个左室心肌节段εsys、εpeak低于对照组,有6个左室心肌节段Srsys低于对照组（P〈0．05或P〈0．01）。HCM有7例患者左室部分节段心肌出现收缩期伸展现象。结论应变和应变率成像技术能准确反映HCM患者左室局部心肌收缩功能减退,并能显示左室局部心肌收缩期伸展现象。