斑点追踪显像技术评价心肌扭转与心肌梗死范围相关性的实验研究

Objective To investigate the most sensitive markers of left ventricular(LV) torsion which can reflect infarct size by assessing the relationship between routine markers of LV torsion and infarct size using speckle tracking imaging (STI).Methods Fifteen open-chest pigs underwent 120 minutes of left anterior descending (LAD) ligation followed by 12 hours of reperfusion.Rotation and torsion of LV were obtained by STI before LAD occlusion,LAD occlusion immediately,and 30,60,90 minutes and 12 hours after reperfusion.Infarct size was measured by nitrotetrazolium blue chloride staining.Results LAD ligation resulted in a dramatic decrease in both subepicardial and subendocardial peak apical rotation or peak LV torsion.Twelve hours after reperfusion,all of the peak rotation and torsion remained significantly reduced (P ＜ 0.01 versus AMI).At AMI,peak bulk LV torsion and peak bulk apical rotation inversely correlated with infarct size (r = - 0.81,P ＜0.01; r = - 0.69,P ＜0.01).There existed the good relationship at 12-hour follow-up after reperfusion.The relationship was superior to that of other torsion markers.Conclusions Peak bulk LV torsion and peak bulk apical rotation are the most sensitive markers of LV torsion which can reflect infarct size.     

速度向量成像评价心尖肥厚性心肌病左室扭转角度和解旋的初步研究

目的 应用速度向量成像(VVI)技术评价心尖肥厚性心肌病(ApHCM)患者左室短轴心肌扭转角度与解旋运动.方法 应用VVI技术对23例ApHCM患者和23例正常人左室短轴心底和心尖水平的心内膜下心肌扭转角度和解旋进行定量分析.结果 与正常组比较,ApHCM组左室短轴心尖部心内膜下心肌收缩期峰值旋转角度、旋转速度以及左室扭转角度均减低(P＜0.05);而两组间心底部心内膜下心肌收缩期峰值旋转角度、旋转速度差异无统计学意义(P＞0.05).ApHCM组舒张早期左室心底部与心尖部心内膜下心肌的峰值解旋速度均低于正常组(P＜0.05).结论 VVI技术可有效评价ApHCM患者左室扭转角度与解旋运动特征,ApHCM患者左室心内膜下心肌的扭转角度与解旋运动均减低.

Abstract：

Objective To evaluate left ventricular(LV) twist and untwist using velocity vector imaging(VVI) in patients with apical hypertrophic cardiomyopathy (ApHCM). Methods Twenty-three patients diagnosed with ApHCM were consecutively enrolled and compared with normal controls. After a standard echocardiographic examination, parasternal basal and apical short-axis planes were scanned to quantify LV rotations,twist and LV untwist using VVI. Results Compared with the normal controls, the rotation and rotaional velocity of apical subendocardial myocardium were markedly decreased in ApHCM patients during the period of systole ( P＜0.05) ,but the decreases in basal planes were not significant. As a consequence,LV twist was significantly lower in ApHCM patients (P＜ 0.05). Compared to normal controls,the velocity of LV untwisting was also significantly decreased in ApHCM patients ( P＜0.05).Conclusions The twist and untwist of LV subendocardial myocardium were decreased in ApHCM patients.VVI is a useful method to assess the characteristics of LV twist and untwist in ApHCM patients.     

扩张型心肌病患者左心室扭转与左心室重构及功能关系的研究

目的 应用二维斑点追踪显像技术(2D-STI)评价扩张型心肌病(DCM)患者左室扭转运动变化对左室重构与功能的影响.方法 DCM患者39例,对照组35例,均接受常规超声心动图、组织多普勒成像检查,获取各受试者左室心底及心尖水平短轴切面观二维图像存盘供Q-lab软件脱机分析.测量参数包括:左室舒张末内径(LVEDd)、左室射血分数(LVEF);左室球化指数(LVSI)、左室重量指数(LVMI);二尖瓣口舒张早期血流速度E、二尖瓣环收缩期运动速度S、舒张早期运动速度E',计算E/ E'; 心底水平和心尖水平左室整体旋转峰值(R心底、R心尖)、左室整体扭转峰值(T)、左室相对扭转(T').结果 与对照组比较,DCM组患者LVEDd、LVMI均显著增大;LVEF及LVSI显著降低; S及E'均显著降低,E/ E'显著增大.根据左室心尖水平旋转方向将DCM患者分为DCM-1组(心尖顺时针旋转)与DCM-2组(心尖逆时针旋转),与对照组比较,两组DCM组患者R心尖、R心底、T、T'均显著减低;与DCM-1组比较,DCM-2组R心底、R心尖、T、T'显著减低,LVEDd、LVMI均显著增大,LVEF及LVSI显著降低,E'显著降低,E/ E'显著增大.结论 DCM患者左室扭转运动减低;心尖水平扭转减低更为显著甚至反向扭转的DCM患者左室重构与功能减低更严重.

Abstract：

Objective To evaluate the effect of torsion on remodeling and function of left ventricle by two-dimensional speckle tracking imaging(2D-STI) in patients with dilated cardiomyopathy(DCM).MethodsThirty-nine patients with DCM and thirty-five controls accepted conventional echocardiography,pulsed-wave Doppler tissue imaging examination.Basal and apical short-axis view of left ventricle were accorded for Q-lab analysis.Indices included:left ventricular diameter in end diastole (LVEDd),left ventricular ejection fraction (LVEF),left ventricular sphericity index (LVSI),left ventricular mass index (LVMI),e-wave of mitral valvular flow (E),velocity of mitral annulus in systole (S),velocity of mitral annulus in early distole ( E'), E/ E',rotation of left ventricle at basal and apical level(Rbasal,Rapical),twist (T),torsion (T').Results Compared with controls,LVEDd,LVMI of patients with DCM increased significantly,LVEF and LVSI decreased significantly,S and E' decreased significantly,E/ E' increased significantly.Patients with DCM were divided into two groups:group DCM-1 (clockwise rotation at apical level) and group DCM-2 (countclockwise rotation at apical level).Compared with controls,Rasal,Rapical,T,T' of two DCM groups decreased significantly.Compared with group DCM-1,Rbasal,Rapical,T,T' of group DCM-2 decreased significantly,LVEDd,LVMI increased significantly,LVEF and LVSI decreased significantly,E' decreased significantly,E/ E' increased significantly.Conclusions The torsion of left ventricle decrease in patients with DCM,DCM patients with decreased or reversed torsion of left ventricular apex have more severe LV remodeling or damage of LV function.     

斑点追踪显像技术评价心肌缺血再灌注对心肌扭转影响的实验研究

目的 应用斑点追踪显像技术测定心肌缺血及再灌注后不同时刻的心肌扭转.方法 14只小型猪,随机分为两组:A组结扎前降支1 min,B组结扎前降支15 min.分别测定结扎前、解除结扎前及解除结扎后第1、5、30、60、90 min、1周各时间点常规心脏超声指标以及扭转数据,并进行比较.结果 缺血时A组心尖部及左室心内膜下扭转角度峰值再灌注后第1 min即恢复至基线水平;而B组相同扭转指标再灌注后30min出现一过性改善,相对于解除结扎前分别为(6.5±0.8).对(3.4±1.2).和(7.8±1.0)°对(6.1±1.1).(P均＜0.01),完全恢复则在再灌注后1周.B组心外膜下扭转角度峰值再灌注后呈逐渐上升趋势.结论 心肌缺血时间不同,再灌注前后心内、外膜下心肌扭转角度改变不尽相同.应用斑点追踪显像技术测定再灌注后心肌扭转恢复情况可以反映心肌缺血程度,从而为评价心肌缺血提供更长时间的观察窗.     

心脏型脂肪酸结合蛋白对急性心肌梗死早期诊断的临床价值研究

Objective To study the clinical value of heart-type fatty acid-binding protein (H-FABP) in early diagnosis of acute myocardial infarction(AMI). Methods Totally 156 patients who were suspicious to be AMI were divided into group A (0～3 h group) and group B (3～6 h group) ac-cording to the visit time. H-FABP,cardiae troponin T (cTnT) and cardiac troponin T (cTnT);Crea-fine kinase isoenzyme-MB (CK-MB) were simultaneously measured at different time-points. The sensi-tivity,specificity and accuracy of the markers were calculated and compared. Results The sensitivity, specificity and accuracy of H-FABP were all the highest among three tumor markers;the sensitivity within 3 hours was 70.7% ,higher than that of cTnT and CK-MB remarkably (P<0.05);the specific-ity was 97.0%; the accuracy was 82.4%, higher than that of cTnT and CK-MB remarkably (P<0.05);while the sensitivity within 3～6 hours was 100.0%, higher than that of cTnT remarkably (P <0.05);the specificity was 92.6%;and the accuracy was 97.6%. Conclusion H-FABP is the most sensitive indicator for early diagnosis of AMI and is of very important value in clinical application.     

斑点追踪成像评价实验兔心肌梗死后骨髓干细胞移植区域心肌收缩功能

目的 应用超声斑点追踪(STI)技术探讨兔左室心肌梗死区域骨髓干细胞移植后的心肌收缩功能.方法 24只健康新西兰兔,随机分为3组:正常对照组(假开胸组)、急性心肌梗死(AMI)组(结扎左冠状动脉前降支,造成左室前壁心肌梗死)和骨髓干细胞移植组(AMI后2周,对梗死区域进行干细胞移植),于骨髓干细胞移植后4周分别采集三组动物左室短轴基底段、中间段及心尖段的动态二维灰阶图像;应用STI技术分析左室不同水平各节段心内膜下心肌径向应变率(SrR)、周向应变率(SrC)、旋转率(RotR)及扭转角度(Rot),常规超声心动图测定左室舒张末期内径(LVEDd)、左室射血分数(LVEF)及左室短轴缩短率(LVFS),心导管测量左室收缩压(LVSP)、左室舒张末期压(LVEDP)、左室压力最大上升及下降速率(LVdp/dtmax).结果 与正常对照组比较,AMI组LVEDd显著增大,LVEF、LVFS显著减低,LVSP、LVdp/dtmax明显降低,LVEDP明显升高,左室前壁局部及左室短轴三水平整体SrR、SrC、RotR和左室Rot均降低;骨髓干细胞移植组LVEDd较AMI组显著减小,LVEF、LVFS明显升高,LVSP、LVdp/dtmax明显升高,LVEDP降低明显,左室前壁局部及左室短轴三水平整体SrR、SrC、RotR和左室Rot均升高,但与正常对照组比较差异无统计学意义.结论 STI可准确评价骨髓干细胞移植区域的心肌功能.

Abstract：

Objective To assess the left ventricular(LV) regional myocardial systolic function after bone marrow mesenchymal stem cells (BMSCs) injection in rabbits with acute myocardial infarction(AMI) by 2-dimensional ultrasound speckle-tracking imaging.Methods Twenty-four healthy rabbits were randomly divided into three groups:group of sham-operated,group of masculine control (AMI was induced by ligation of left anterior descending coronary artery),and group of cell infusion(after two weeks of AMI,bone marrow mesenchymal stem cells were injected to the region of AMI).Four weeks after cell deliver two-dimensional strain images were acquired from LV short-axis view(at the levels of mitral annulus,muscle papillary and apex),radial strain rate (SrR),circumference strain rate (SrC),rotation rate (RotR) and rotation (Rot) of three levels in short-axis views were measured by speckle-tracking imaging.The conventional echocardiography indices included LV diameter of end diastole(LVEDd),LV ejection fraction(LVEF),LV fractional shortening(LVFS).The catheter indices included LV systolic pressure(LVSP),LV end diastolic pressure (LVEDP)and maximum rate of rise and descend of LV pressure(LVdp/dtmax).ResultsCompared with sham-operated group,rabbits had significantly larger LVEDd,lower LVEF and LVFS,lower LVSP and LVdp/dtmax,higher LVEDP in control group,SrR,SrC,RotR and Rot of LV anterior regional myocardial function and global myocardial function of three levels in short-axis views were lower.Compared with control group,the rabbits had significantly smaller LVEDd,larger LVEF and LVFS,larger LVSP and LVdp/dtmax,lower LVEDP,SrR,SrC,RotR and Rot of LV anterior regional myocardial function and global myocardial function of three levels in short-axis views were larger in group of cell infusion.There was no significant between group of cell infusion and group of sham-operated.Conclusions Speckle tracking imaging can evaluate the regional myocardial systolic function of the area of BMSCs transplantation accurately.     

定量组织速度成像评价二尖瓣置换术后左心功能的临床研究

目的 探讨定量组织速度成像(QTVI)评价二尖瓣置换术(MVR)后左室整体和局部功能的临床价值.方法 80例MVR术后患者作为病例组,根据心律分为窦性心律组40例和心房颤动(房颤)组40例.常规超声心动图检查后采集心尖四腔观、心尖两腔观、心尖左室长轴观的组织多普勒动态图像,启动QTVI模式,绘制左室各壁瓣环、心肌节段的时间-速度曲线.测量收缩期峰值速度(Sa、Sm)和快速舒张期峰值速度(Ea、Em)等.结果 ①与正常组比较,MVR组6个壁二尖瓣环和各心肌节段Sa、Sm和Ea、Em均明显减低(P<0.001);②二尖瓣环收缩期平均峰值速度(Sa')与左室射血分数(LVEF)呈正相关(P<0.001);③二尖瓣环快速舒张期平均峰值速度(Ea')与等容舒张期时间均值(IVRT')呈负相关(P<0.01).结论 QTVI能够评价MVR术后左室整体和局部的收缩与舒张功能,具有重要的临床价值.

Abstract：

Objective To evaluate the clinical value of quantitative tissue velocity imaging (QTVI) in assessing left ventricular(LV) global and regional myocardial function in patients with mitral valve replacement(MVR).Methods Eighty patients having their implantations for more than six months were examined by echocardiography.QTVI-derived parameters such as peak systolic velocity(Sa,Sm) and early diastolic velocity(Ea,Em) of mitral annulus and LV wall were measured from the apical four-chamber,two-chamber and long axis corresponding myocardial segments in MVR groups decreased and LV ejection fraction but negative correlation between Ea' and isovolumic relaxation time(IVRT') in patients(P<0.01).Conclusions QTVI plays an important role in determining LV function of patients after MVR accurately.     

二维斑点追踪技术评价舒张性心力衰竭患者左室心内膜和心外膜下心肌功能

目的 应用二维斑点追踪成像技术评价射血分数正常的舒张性心力衰竭(diastolic heart failure,DHF)患者左室心内、外膜下心肌功能.方法 临床确诊的DHF患者36例、收缩性心力衰竭(systolic heart failure,SHF)患者20例及正常对照组41例.二维超声心动图分别存储胸骨旁左室短轴基底水平、心尖水平连续3个心动周期的二维灰阶图像.使用Qlab 7.0工作站进行脱机分析,记录左室上述两短轴切面心内、外膜下心肌旋转角度.结果 ①所有受检者左室同一水平心内、外膜下心肌旋转运动呈相同方向运动,心尖水平呈逆时针方向旋转,基底水平呈顺时针方向旋转.②心尖水平及基底水平心内膜下心肌旋转角度均大于心外膜下心肌旋转角度.③与正常对照组相比,DHF及SHF患者心尖水平心内膜下心肌旋转角度减低;DHF患者心尖水平心外膜下心肌旋转角度与正常组比较未见明显减低,SHF组较正常组及DHF组明显减低.④DHF组基底水平心内、外膜下心肌旋转角度较正常对照组相应心肌层旋转角度值减低,但差异无统计学意义.SHF患者基底水平心内、外膜下心肌旋转角度显著减低.结论 SHF患者左室心内膜下心肌和心外膜下心肌旋转运动减低;DHF患者左室心尖水平心内膜下心肌旋转运动减弱,射血分数正常的DHF患者存在收缩功能异常.

Abstract：

Objective To observe the rotation of subendocardium and subepidium by two-dimensional speckle tracking imaging(2D-STI),and to evaluate its performance in diastolic heart failure patients(DHF)with a normal left ventricular ejection fraction. Methods Ninety-seven consecutive clinically stable patients were enrolled in this study [41 healthy controls,36 with diastolic heart failure,20 with systolic heart failure (SHF)]. High frame rate dynamic two-dimensional images were recorded at the left ventricular short-axis view,including basal, papillary muscle and apical planes. Subendocardial and subepicardial global rotation were measured using Q-lab 7.0 software offline. Results ① In all the subjects, the rotation of the subendocardium was obviously greater than that of subepicardium. ②As seen from the apex,left ventricular subendocardium and subepicardium performed a wringing motion with a clockwise rotation at the base and countclockwise rotation at the apex. ③In the apical plane, subendocardial rotation was significantly lower in both heart failure groups than in controls,and was depressed to a larger extent in SHF patients than in those with DHF. Subepicardial rotation was no significant difference between the DHF group and the control group, though it was significantly lower in patients with SHF. ④At the base, the rotation of subendocardium and subepicardium were not different between DHF and control groups, but it was significantly reduced in patients with SHF. Conclusions The subendocardial rotation is reduced, but subepicardial rotation is normal in DHF patients. On the other hand, in patients with SHF, subendocardial and subepicardial rotation are both reduced. The left ventricular systolic properties are impaired in DHF patients.     

血流向量成像技术评价肥厚型心肌病左心室收缩期血流动力学特征

目的 应用超声血流向量成像(VFM)技术评价肥厚型心肌病(HCM)左室收缩期血流动力学特征及流场分布特点.方法 随机选取肥厚型非梗阻性心肌病患者35例作为病例组,健康成年志愿者40例为对照组,比较两组左室收缩期峰值流速(Vs)、峰值流量(Fs)及收缩期负向总流量(SQ-),观察两组速度向量、流线和涡流分布特点.结果 对照组Vs、Fs、SQ- 及病例组Vs、Fs均由基底段、中间段至心尖段呈递减趋势,差异均有统计学意义(P＜0.05);而病例组SQ- 失去这种顺序递减趋势.病例组各节段Vs、Fs及中间段、心尖段SQ- 均大于对照组,但基底段SQ- 明显小于对照组(P＜0.01).与对照组比较,病例组血流流场分布特点为速度方向混乱,流速快,流线不连续,涡流增多.结论 VFM技术能够定量评价HCM患者左室收缩期血流动力学特征,并能清晰显示血流流场的分布情况.

Abstract：

Objective To investigate the left ventricular(LV) systolic hemodynamics and the distribution of blood flow in patients with hypertrophic cardiomyopathy(HCM) by vector flow mapping(VFM).MethodsThirty-five random non-obstructive HCM patients(case group) and forty healthy volunteers (control group) were enrolled.Peak systolic velocity (Vs),peak systolic flow (Fs) and total systolic negative flow (SQ-) of two groups were compared.Velocity vector,streamline and vortex distribution of two groups were observed.Results Vs,Fs,SQ- of the control group and Vs,Fs of the case group all showed a decreasing trend from the basal segments to the apical segment(P<0.05).SQ- of the case group lost this decreasing tendency.Vs,Fs of all segments and SQ- of the middle and apical segment of the case group were higher than those of the control group.SQ- of the basal segment of the case group were significantly lower than that of the control group(P＜0.01).Distribution of blood flow:The velocity of blood flow was faster in the case group than that in the control group and the direction was disordered.The streamlines of the case group were discontinuous,and vortexes in the case group were more than that in the control group.Conclusions VFM technology could quantitatively evaluate LV systolic hemodynamics in patients with HCM,and can clearly show the distribution of blood flow.     

超声三维斑点追踪技术评价慢性心功能不全患者左室旋转及扭转运动的初步研究

目的 应用超声三维斑点追踪技术(three-dimensional speckle tracking,3DT)评价慢性心功能不全(chronic heart failure,CHF)患者左室旋转及扭转运动特征,并探讨扭转角度峰值与位移参数的相关性.方法 CHF患者28例和健康志愿者32例,经胸同时采集心尖四腔和两腔切面动态图像后,获取左室三维全容积动态图像,存储图像后运用3DT软件进行脱机分析,得到左室心底水平各节段旋转角度峰值(peak basal rotation,Prot-B)和心尖水平各节段旋转角度峰值(peak apical rotation,Prot-A)、左室整体旋转角度峰值(LVrot)和扭转角度峰值(LVtw)、左室整体最大径向位移(radial displacement,Dr)、纵向位移(longitudinal displacement,D1)、三维位移(three-dimensional displacement,D3d)等指标.比较CHF组和正常对照组上述指标之间的差异,并分析左室扭转角度峰值和位移参数的相关性.结果 (1)CHF组Prot-A和Prot-B均较对照组明显减低,差异有统计学意义(P＜0.01或0.05);CHF组LVrot和LVtw均较对照组明显减低,差异均有统计学意义(P＜0.001);(2)CHF组Dr、D1和D3d均较对照组明显减低,差异有统计学意义(P＜0.05);(3)CHF组LVtw与Dr、DI、D3d间均有良好相关性,(P＜0.01或0.05).结论 3DT可以在三维立体空间内研究左室的旋转及扭转运动,从机械力学角度评价CHF患者左室收缩功能减低.     

斑点追踪技术对急性心肌梗死患者再灌注治疗前后内、外膜心肌扭转的研究

目的 应用斑点追踪技术通过心内膜旋转角度、心外膜旋转角度及跨壁角度梯度三者峰值指标对急性心肌梗死(心梗)患者再灌注治疗前、后室壁运动异常及心功能进行评价.方法 正常对照组20例,急性前壁心梗患者21例,对正常组、心梗术前及术后1月分别行常规超声检查后,获取左室心尖及心底短轴切面二维图像各3个心动周期,使用QLab软件进行脱机分析,得到两短轴切面心内、外膜旋转角度及跨壁角度梯度.结果 无论在心尖还是在心底短轴切面,与正常组相比,术前组内膜旋转角度峰值、外膜旋转角度峰值及跨壁角度梯度峰值均降低(P<0.01).再灌注治疗1月,术后组上述三个指标均较术前组有不同程度改善,差异有统计学意义(P<0.05),且内膜改善优于外膜.同时,左室射血分数(r=0.717,P<0.01)、舒张末容积(r=-0.694,P<0.05)与心尖内膜旋转角度峰值相关良好,而与心底及心尖其他各指标无明显相关性.结论 心内、外膜旋转角度及跨壁角度梯度峰值是评价急性心梗患者再灌注治疗前、后室壁运动异常及心功能的敏感指标之一.     

应用斑点追踪成像技术对急性心肌缺血及再灌注心内膜下心肌和心外膜下心肌旋转及扭转功能的研究

目的：本研究旨在应用斑点追踪成像（STI）技术通过测定心内、外膜下心肌、跨壁旋转及扭转角度等指标对急性心肌缺血及再灌注期间心脏功能进行评价。方法：对20只健康成年杂种犬结扎左冠状动脉第一对角支下方180 min并再灌注120 min,分别对结扎前、结扎即刻、结扎60 min、结扎120 min和结扎180 min及再灌注即刻、再灌注60 min和再灌注120 min基底水平和心尖水平的旋转及扭转指标进行比较。结果：①基底水平旋转的比较：随着缺血时间延长,跨壁角度逐渐减低。再灌注即刻,跨壁角度一过性增大。再灌注120 min,跨壁角度最低。②心尖水平旋转的比较：跨壁角度从结扎即刻开始下降,至结扎180 min达到最低值。再灌注即刻,跨壁角度快速上升。再灌注60 min、120 min缓慢上升。③扭转的比较：随着缺血时间的延长,跨壁扭转角度明显下降。结扎180 min跨壁扭转角度最低。再灌注即刻跨壁扭转角度快速恢复。结论：STI技术通过定量分析左室心内膜及心外膜下心肌局部和整体的旋转及扭转,可以判断心脏功能的变化。心内外膜下心肌旋转角度及跨壁角度、扭转角度及跨壁角度是评价急性心肌缺血及再灌注后室壁运动及心脏功能的有效手段。     

速度向量成像技术定量评价正常人左心室扭转运动

目的 采用速度向量成像技术研究正常人的左心室心内膜和心外膜扭转运动特点.方法 对10例正常成年人行常规超声心动图和二维斑点显像检查.斑点追踪切面包括基底切面(二尖瓣水平左心室短轴)和心尖切面(心尖水平左心室短轴),应用Siemens SyngoWorkPlace V 2.0 工作站进行后处理分析.结果 无论是心内膜或心外膜,左心室基底部收缩期旋转均为负值,舒张期旋转均为正值,心尖部则相反,收缩期心尖部旋转速度的绝对值显著高于基底部[心内膜:(150±62)°/s 对 (114±65)°/s;心外膜:(81±40)°/s和(55±28)°s,均 P<0.01)].无论是基底部或心尖部,收缩期心内膜旋转速度和旋转角度均显著高于心外膜[基底部:(-114±65)°/s对 (-55±28)°s,(-12±6)°对(-4±1)°;心尖部:(150±62)°/s对 (81±40)°/s,(10±4)°对 (6±2)°,均 P＜0.05)]°收缩期基底部和心尖部心内膜和心外膜平均旋转速度达峰时间[基底部(188±72)ms 对 (187±55)ms;心尖部(195±85)ms 对 (141±79)ms3、舒张期基底部和心尖部心内膜和心外膜平均旋转速度达峰时间[基底部(446±58)ms 对 (491±53)ms;心尖部(453±57)ms 对 (466±85)ms]及收缩期心内膜和心外膜平均旋转的达峰时间[基底部(296±69)ms对(292±63)ms;心尖部(251±67)ms 对 (295±66)ms]差异均无统计学意义(P＞0.05).结论 速度向量成像技术可无创伤性评价左心室环向旋转和扭转运动,正常人左心室具有特征性旋转运动.     

超声斑点追踪成像技术对2型糖尿病患者左心室扭转运动早期变化的初步研究

目的 探讨超声斑点追踪成像技术评价2型糖尿病患者左心室扭转运动早期变化的临床应用价值.方法 2型糖尿病患者66例,且左心室射血分数≥50%,其中单纯糖尿病41例,糖尿病并左心室肥厚25例,正常对照者37例.采集受检者胸骨旁短轴二尖瓣水平、心尖水平二维图像,测量各水平收缩期平均旋转角度峰值、各室壁节段旋转角度峰值,计算左心室整体扭转角度峰值.结果 与对照组比较,单纯糖尿病组各水平平均旋转角度峰值、心尖水平各室壁节段旋转角度峰值及左心室整体扭转角度峰值均较对照组增大（P＜0.05或P＜0.01）.糖尿病并左心室肥厚组二尖瓣水平部分室壁节段、心尖水平各室壁节段旋转角度峰值及各水平平均旋转角度峰值较对照组增大（P＜0.05或P＜0.01）,心尖水平部分室壁节段旋转角度峰值及平均旋转角度峰值较单纯糖尿病组增大（P＜0.05或P＜0.01）,左心室整体扭转角度峰值较正常对照组和单纯糖尿病组大（P＜0.01）.结论 在左心室收缩功能正常时,单纯糖尿病患者左心室扭转角度增大,合并左心室肥厚者更加明显,超声斑点追踪成像能够较早识别糖尿病患者左心室扭转角度改变.     

斑点追踪成像技术评价冠状动脉不同狭窄程度患者的左室扭转运动

目的 应用斑点追踪成像(STI)技术评价冠状动脉不同狭窄程度患者左室扭转运动的特点及规律性.方法 临床拟诊为冠心病患者117例,根据冠状动脉造影或冠状动脉CT结果分成心肌梗死组(60例)、心肌缺血组(31例)及对照组(26例),常规超声测量左室收缩及舒张末期内径(LVDs,LVDd)、容积(LVVESV,LVEDV)及射血分数(LVEF),组织多普勒测量二尖瓣后瓣环收缩期峰值运动速度(S')及Tei指数,运用STI技术分析左室二尖瓣水平与心尖水平旋转运动、整体扭转运动,测定旋转角度/率、扭转角度/率.结果 与心肌缺血组及对照组比较,心肌梗死组LVDd、LVDs、LVEDV、LVESV及Tei指数均增大,LVEF及S'减低,差异均有统计学意义(P<0.05).与对照组比较,心肌梗死组及心肌缺血组左室心尖水平旋转角度/率、二尖瓣水平旋转率、扭转角度/率均减低,差异均有统计学意义(P<0.05),以心肌梗死组减低更为显著(P<0.01).左室整体的扭转角度与LVEF呈较强的正相关(r=0.618,P<0.001).结论 冠心病患者的冠状动脉狭窄程度越严重,左室整体的扭转运动受损越明显,以心肌梗死组减低更为显著.应用STI评价左室的扭转运动与常规超声参数相比较,能更好地反映心肌缺血患者的左心室收缩运动.     

斑点追踪显像对房间隔缺损患者左心旋转和扭转运动的初步研究

目的 探讨房间隔缺损(ASD)患者右心容量负荷和压力负荷过重对左心旋转和扭转运动的影响.方法 应用斑点追踪显像技术分别测量35例单纯ASD患者(其中18例伴肺动脉高压)左室基底部短轴和心尖部短轴6个节段的旋转峰值及其收缩早期反方向旋转的平均峰值和平均持续时间;绘制左室扭转-时间曲线,计算扭转峰值及达峰时间;双平面Simpson法测量左室射血分数(EF).21例正常人作为对照组.结果 与ASD肺动脉高压阴性组及正常组相比,ASD肺动脉高压阳性组基底部后壁、下壁、后室间隔的顺时针旋转角度峰值降低(P＜0.05),6个节段早期逆时针旋转的平均峰值增加(P＜0.05),平均持续时间延长(P＜0.05),左室整体扭转角度峰值亦降低(P＜0.05).ASD肺动脉高压阴性组各指标与正常组的差异无统计学意义.左室扭转角度峰值与肺动脉收缩压呈明显负相关(r=-0.57,P=0.001).三组间射血分数无明显差异.结论 单纯ASD引起的右心容量负荷增加并不明显改变左室旋转和扭转运动,而肺动脉压增高时左室扭转峰值降低,且与肺动脉收缩压呈明显负相关.     

吗啡对急性心肌梗死再灌注损伤保护效应的实验研究

目的　通过测定急性心肌梗死再灌注损伤模型大鼠的血浆降钙素基因相关肽 (CGRP)、内皮素(ET 1)浓度及心肌梗死面积的变化 ,探索吗啡对急性心肌损伤的保护机制。方法　将 4 0只 SD大鼠随机分为单纯缺血再灌注模型组、吗啡预处理组、吗啡 纳洛酮组和手术对照组 ,每组各 10只。采用戊巴比妥钠(40 m g/ kg)腹腔注射麻醉大鼠 ,采用穿线结扎左冠状动脉前降支制备大鼠心肌缺血再灌注模型。用放射免疫法测定血浆 CGRP和 ET 1浓度 ,同时测定血清中肌酸磷酸激酶同工酶 (CK MB)含量 ;用氯化三苯四唑(TTC)法染色和数码照相计算机图像分析系统计算心肌梗死面积。结果　大鼠左冠状动脉前降支结扎 10 m in时血浆 ET 1和 CGRP浓度较手术对照组显著增高 (P均 <0 .0 1) ;再灌注 4 .5 h时吗啡预处理组血浆 ET 1及 CK MB浓度较结扎 10 m in时显著降低 ,心肌梗死面积也显著缩小 (P均 <0 .0 1) ;而血浆 CGRP浓度则显著增高 (P<0 .0 1) ;吗啡预处理组以上变化较吗啡 纳洛酮组差异有统计学意义 (P均 <0 .0 1)。结论　吗啡预处理可通过显著降低 ET 1而增加 CGRP血浆浓度、缩小心肌梗死面积 ,对急性心肌梗死后再灌注心肌产生保护效应。     

斑点追踪技术对ST段抬高及非ST段抬高心肌梗死介入治疗前后心肌内、外膜旋转的研究

目的 应用斑点追踪技术对ST段抬高及非ST段抬高心肌梗死患者介入治疗前后心内膜、心外膜旋转角度峰值变化进行评价,以探讨两种心肌梗死的透壁程度.方法 研究共分3组:A组为20例正常人;B、C组分别为26例ST段抬高及22例非ST段抬高心肌梗死患者.A组及B、C组术前、术后1月分别行常规超声检查后,获取左室心尖部及基底部各3个心动周期的二维图像,最后应用工作站Qlab软件脱机分析,得到心尖、心底及左室心内、外膜旋转角度.结果 无论在心尖部、基底部.还足在左室整体,B、C组术前心内、外膜旋转角度峰值均明显低于A组(P<0.01).介入治疗后1月,仅C组的心尖及左室心外膜旋转角度峰值较术前显著改善(P<0.01).左室心外膜扭转角度峰值与射血分数呈正相关(r=0.63,P<0.05),与室壁运动积分指数呈负相关(r=-0.85,P<0.01).结论 应用斑点追踪技术测定心内、外膜旋转角度峰值能较好地反映ST段抬高及非ST段抬高心肌梗死透壁程度,且与心功能及室壁运动存在一定关系.     

犬急性心肌梗死与再灌注的多层螺旋CT评价实验研究

目的探讨多层螺旋CT评价急性冠状动脉闭塞后心肌梗死及再灌注的能力.方法将12只杂种犬随机分成两组:①急性心肌梗死组(AMI),分别于结扎冠状动脉前、结扎后1 h和2 h进行CT平扫和增强扫描.②AMI再灌注组,分别于结扎前、结扎后1 h及再灌注30 min进行同样扫描.观察心肌梗死的病变部位及形态,测量每组正常心肌、心肌梗死部位在各个扫描时点的CT值,计算两者与左心室腔的CT值之比(M/L).结果12只犬结扎左前降支后1 h增强图像上左心室前壁或心尖区均有明显的低密度区形成.AMI组结扎后2 h图像缺血区的密度更为减低;AMI再灌注组再灌注30 min后病变的密度变化不明显.AMI组结扎后1 h与2 h的正常心肌与梗死心肌的CT值均值及两者与左心室腔的M/L均具有显著性差异(P＜0.001).AMI再灌注组结扎后1 h与再灌注后30 min正常心肌与梗死心肌的CT值均值及两者与左心室腔M/L也具有显著性差异(P＜0.001).结论急性冠脉闭塞后心肌梗死区MSCT表现为低密度,MSCT能够区分急性冠状动脉闭塞后梗死心肌与正常心肌.