负荷DTI二尖瓣环舒张期波形改变对心肌缺血的提示意

目的了解负荷DTI二尖瓣环舒张期波形改变对心肌缺血的提示意义.方法利用DTI观测104例冠状动脉造影(CA)患者的二尖瓣环舒张期4个位点的e波与a波的比值在多巴酚丁胺应用前后的变化,并与CA结果进行比较.结果基础状态下DTI二尖瓣环4个取样点的e/a均＜1.0时,冠心病的检出率较高,而二尖瓣环4个取样点的e/a均≥1.0时的冠脉病变率最低(P＜0.01);负荷条件下原本各点e/aann≥1.0的一些病例中出现部分取样点的e/aann＜1.0改变,其冠脉病变率增高或有增高的趋势(P＜0.05),而试验前后维持e/aann≥1.0波形的病例的冠脉病变率有下降的趋势.结论负荷剂量下不同位点的e/aann发生变化使得DTI以e/aannn＜1.0为指标提示冠心病的准确度、灵敏度、特异度、阳性预测值和阴性预测值和以e/aann≥1.0为指标排除冠心病的准确度、特异度、阳性预测值均有所提高.     

多普勒组织成像技术对冠心病患者二尖瓣环运动曲线的探讨

目的 本文旨在运用多普勒组织成像技术观察冠心病患者二尖瓣环运动曲线以评估其左室收缩和舒张功能。 方法32例冠心病患者和20例正常人作对照研究,测定其二尖瓣环后间隔、侧壁、下壁、前间隔和后壁六处各位点的Sa、Ea、Aa及Ea/Aa之比。 结果 1.冠心病患者和正常人二尖瓣环的DTI运动曲线为规律波群,有三个主波,收缩波Sa波,舒张早期Ea波,舒张晚期Aa波 2.冠心病患者二尖瓣环六个节点Sa、Ea及Ea/Aa较正常组显著下降(P<0.01)3.冠心病患者二尖瓣环六个节点平均Sa与左室射血分数呈正相关(r=0.689,P<0.01)平均Ea/Aa与二尖瓣血流曲线E/A之比也有良好相关性(r=0.427 P<0.05)4.正常组与冠心病组心尖四腔观二尖瓣环侧壁Sa、Ea/Aa之比与六个节点平均参数相关系数最大。 结论 DTI测量二尖瓣环运动曲线能同时测定左室收缩、舒张功能,从而提供了一种新的、安全的、直接可靠的、简便的方法。     

心室功能评估中房室瓣环组织多普勒波形的测定

在诸多无创性评估心室功能的检测手段和方法中,多普勒组织成像(DTI)正得到临床的广泛应用,房室瓣环组织多普勒波形改变对心室功能的提示意义也逐渐受到重视.房室瓣环的运动代表了心肌纤维由基底部向心尖的运动,瓣环运动速度的测定可提供心室收缩期到舒张早期运动状态的信息.DTI获得的二尖瓣环收缩期运动速度波形可反映心梗缺血壁段引起的左室壁不协调性,并可用这些参数评价左室的整体收缩功能.三尖瓣环的DTI运动速度可以用于评价与下壁心梗相关的右室功能.因受前负荷变化的影响小,二尖瓣环DTI有助于鉴别二尖瓣的假阴性血流频谱,有助于无创性评估左室充盈压.一些影响房室瓣环DTI运动速度测定的因素目前难以消除,需结合其他多普勒参数和临床表现来分析.     

多巴酚丁胺负荷试验结合脉冲组织多普勒二尖瓣环运动定量评估心肌梗死患者心肌存活

目的研究脉冲多普勒组织成像技术(DTI-PW)中二尖瓣环速度检测存活心肌的可行性及价值.方法 40例陈旧性心肌梗死患者室壁按照硝酸甘油(NTG)介入99Tcm-MIBI SPECT 结果分为有存活心肌组、无存活心肌组,采用小剂量多巴酚丁胺负荷超声心动图试验,测量相应梗死壁二尖瓣环多巴酚丁胺(Dobutamine,Dob)负荷前及每级Dob负荷试验时的收缩期峰值速度Vs、射血前期PEP、射血期ET;另选20例年龄匹配的正常人为对照组,测量6个室壁二尖瓣环Vs、PEP、ET.结果 Dob 5μg/(kg·min)时,以Vs增加量≥2 cm/s为临界值,则检测存活心肌的敏感度为75%,特异度为76%,准确度为75%,以PEP/ET变化率2(Dob 5μg/(kg·min)时PEP/ET与Dob负荷前PEP/ET的比值)≥100%作为诊断无存活心肌的临界值,则敏感度为73%,特异度为85%,准确度为79%;以Dob 10 μg/(kg·min)时Vs增加量≥3 cm/s为临界值,则检测存活心肌的敏感度增加到83%,特异度为79%,准确度增加到81%,以PEP/ET变化率3(Dob 10μg/(kg·min)时PEP/ET与Dob负荷前PEP/ET的比值)≥100%作为诊断非存活心肌的临界值,则敏感度为82%,特异度为85%,准确度为84%.结论 Dob负荷时二尖瓣环Vs、PEP/ET可用于检测存活心肌,方法简单、可靠.     

Mitral annular velocity by Doppler tissue imaging for the evaluation of atrial stunning after cardioversion of atrial fibrillation

Objective Atrial and/or appendage stunning (AS) usually occur after successful cardioversion of atrial fibrillation (AF). Several parameters except mitral annular velocity were previously evaluated to determine AS. We investigated whether mitral annular velocity was useful for determining of AS. Methods This study consisted of 52 consecutive patients with AF <3 months who converted to the sinus rhythm. Mitral inflow and annular velocities were measured before and after cardioversion. Left atrial appendage (LAA) size and flow were assessed. The average velocity of septal and lateral segments of mitral annulus was considered as the final annular velocity. Thrombus and/or spontaneous echo contrast (SEC) were also investigated. Results Of 52 patients, 29 (56%) had AS but 23 did not. There was no significant difference in age, gender, and cardioversion type between two groups. Hypertension was more prevalent in patients without AS compared to those with AS (P = 0.02). Mitral annular systolic and E-wave velocities were comparable in both groups (P > 0.05). Mitral annular A-wave velocity (3.1 ± 2.9 vs. 7.1 ± 2.2 cm/s, P < 0.001), and its velocity-time integral (0.27 ± 0.22 vs. 0.74 ± 0.19 cm, P < 0.001) were significantly lower in patients with AS compared with those without AS. The annular A-wave velocity ≤3.3 cm/s predicted AS with a sensitivity of 59% and specificity of 76%. It was correlated with mitral inflow A velocity (r = 0.85, P < 0.001), LAA emptying velocity (r = 0.41, P = 0.003) and presence of SEC (r = −0.52, P < 0.001). Conclusion After cardioversion of AF, mitral annular A-wave velocity may be a new marker to determine AS.     

多普勒组织成像技术分析冠心病患者多巴酚丁胺超声负荷试验中缺血心肌运动的变化

目的：探讨多普勒组织成像技术（DIT）定量分析多巴酚丁胺超声负荷试验（DSE）过程中缺血心肌室壁运动的特征。方法：分别对14例正常人和20例冠心病患者采用标准的DSE方案（0－40μg.kg^-1.min^-1），使用DIT技术于静息状态，小剂量（10μg.kg^-1.min^-1）及峰值剂量（40μg.kg^-1.min^-1）负荷时观察心肌运动速度的变化，记录各室壁节段收缩期的峰值速度，峰值速度运动时间，综合计算平均收缩期室壁运动峰值速度和平均峰值速度运动时间，结果：随着多巴酚丁胺药物剂量的增加，正常组平均峰值速度均逐渐增加，平均峰值速度运动时间逐渐缩短；冠心病组平均峰值速度小剂量负荷时增加，大剂量时则下降，平均峰值速度运动时间呈逐渐缩短趋势，两组间各指标相比差异有显著性意义（P＜0．001）。结论：DTI技术与DSE结合可定量评价缺血心肌室壁运动异常，对冠心病缺血心肌的无创性诊断具有应用价值。     

定量组织速度成像测定二尖瓣环运动评价冠心病患者左室功能

目的 通过定量组织速度成像(QTVI)技术测量二尖瓣环运动速度,以评价冠心病(CAD)患者左心室功能变化.方法 对经冠状动脉造影确诊的52例CAD患者,采用QTVI技术分别测量窦性心律时二尖瓣环6个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),并计算6个位点各参数的总和(t)及平均值(m),同时测定左室射血分数(LVEF)、左心室舒张末期容积(LVE DV)、左心室收缩末期容积(LVESV),并与36例正常组(对照组)的相应参数进行比较.结果 ①与正常组比较,CAD组Vs、Ve、Va及LVEF均有显著减低(P＜0.01),L VESV、LVEDV明显增加(P＜0.01).②CAD组LVEF与Vs-t、Vs-m、Ve-m成正相关( r=0.568,P＜0.01;r=0.578,P＜0.01;r=0.361,P＜0.01),C AD组Vs-m与Ve-m成正相关(r=0.584,P＜0.01).③采用正常组75%正常参考值下限(Vs-m-0.67s＝5.04 cm/s)作为诊断CAD的标准,其敏感性、特异性及准确性分别为66.7%、82.9%及73.2%.结论 CAD患者存在局部和整体心肌收缩、舒张功能障碍,而且收缩功能受损与舒张功能受损密切相关;用QTVI测量二尖瓣环运动检测CAD患者心功能障碍具有肯定的临床价值;Vs-m是评价CAD患者心功能障碍的良好指标.     

Age-related changes in diastolic atrioventricular annular velocity: Studies using pulsed Doppler tissue imaging

Age-related changes in the diastolic velocity of the mitral and tricuspid annuli were studied in 67 healthy subjects aged 15 to 79 years. Ventricular inflow velocities were recorded by pulsed Doppler echocardiography with sample volumes at the mitral and tricuspid orifices in the apical four-chamber view, and peak early (E) and late (A) diastolic velocities were measured. Atrioventricular annular velocities were recorded by Doppler tissue imaging with sample volume set on the lateral portion of each annulus in the same view, and peak early (Ea) and late (Aa) diastolic velocities were determined. E and Ea correlated inversely with age, while A and Aa correlated directly with age in both ventricles. E/A and Ea/Aa ratios correlated inversely with age in both ventricles. Coefficients of correlation of these variables with age were higher for annular velocity than for inflow velocity. The E/A ratio at the tricuspid orifice was higher than that at the mitral orifice in all decades. An E/A ratio of less than 1 was observed at the mitral orifice in the sixth decade, but at the tricuspid orifice in the seventh decade. The Ea/Aa ratio at the tricuspid annulus was lower than that at the mitral annulus in all decades. The Ea/Aa ratio was less than 1 at the mitral annulus in the fifth decade and at the tricuspid annulus in the fourth decade. Diastolic function of both ventricles thus deteriorates with age, and diastolic annular velocity reflects ventricular diastolic function more accurately than ventricular inflow velocity.     

组织多普勒测量二尖瓣环下行速度评价左室收缩功能

目的：用组织多普勒显像技术测量二尖瓣环下行速度评价左室收缩功能。方法：该研究对５０例正常人和进行门控心血池造影后３小时的３０例心肌梗塞患者的收缩期二尖瓣环下行速度进行测量,分别在心尖四腔切面和二腔切面上测量二尖瓣环间隔处（ＭＡＶ－Ｓ）、侧壁处（ＭＡＶ－Ｌ）、前壁处（ＭＡＶ－Ａ）、后壁处（ＭＡＶ－Ｐ）的各点处的速度值,并计算各点均值（ＭＡＶ－Ｍ）。结果：１．心梗患者各点的速度及均值均较正常对照组明显下降,且发现不同部位心梗,其二尖瓣环各点速度下降程度不同;２．将全部受检者的ＭＡＶ－Ｍ与２ＤＥ所测得的ＥＦ进行相关分析,也存在明显相关,相关系数０．８９（Ｐ＜０．００１）。此外,将３０例心梗患者的ＭＡＶ－Ｍ与核素测得的ＥＦ进行相关分析,也存在明显相关,相关系数０．８７（Ｐ＜０．００１）。结论：测量二尖瓣环下行速度可作为一个评价左室收缩功能的新指标。     

多普勒组织成像评价多巴酚丁胺负荷试验中左心室长轴局部心肌收缩功能

目的　探讨大剂量多巴酚丁胺负荷试验下脉冲多普勒组织成像技术 (PW DTI)评价左心室长轴局部心肌收缩功能的临床价值。方法　冠心病患者 3 0例 (至少 1支冠状动脉主支狭窄≥ 5 0 % ) ,对照组 2 5例 ,均行大剂量多巴酚丁胺负荷试验 ,分别于静息、峰值负荷下将PW DTI取样容积置于侧壁、室间隔、前壁、下壁心肌基底段、中段心内膜下心肌采样 ,获取各节段心肌运动速度曲线。PW DTI测量指标 :收缩期峰值运动速率 (Vs)、收缩期达峰时间 (timetopeakvelocity ,TPV)、收缩期速度时间积分 (velocity timeintegral,VTI)。 结果　根据多巴酚丁胺负荷超声心动图及冠状动脉造影结果将冠心病组患者心肌节段区分为正常节段与缺血节段。与对照组相应节段 (正常组 )比较 ,静息状态下 ,冠心病缺血节段组与正常组节段间Vs、TPV、VTI并无统计学差异 ;峰值负荷下冠心病缺血节段组各节段Vs、VTI明显减低 (P <0 .0 5 ) ,而TPV则显著延长 (P <0 .0 5 )。结论　PW DTI能准确评价多巴酚丁胺负荷试验中左室长轴局部心肌收缩功能 ,从而准确无创检测冠心病缺血心肌。