硝酸甘油介入心肌断层显像对存活心肌的判断价值

目的探讨硝酸甘油介入心肌断层显像对心肌梗死（MI）患者存活心肌的判断价值。方法64例心肌梗死患者经皮冠状动脉介入治疗术（PCI）前行^99mTc-MIBI静息和硝酸甘油（NTG）介入心肌显像，术后3个月时复查静息心肌显像，并进行对比分析。结果64例患者静息显像共有232个节段（40．28％）心肌核素摄取异常，NTG介入心肌显像后有132个节段（56．90％）呈可逆性缺损，100个节段（43．10％）呈不可逆性缺损；PCI术后136个心肌节段（58．62％）心肌灌注得到改善，术前NTG介入显像显示的132个可逆性缺损节段，术后120个节段（90．91％）心肌灌注改善，术前NTG介入显像显示的100个不可逆性缺损节段，术后16个节段（16．0％）心肌灌注改善，二者比较差异有统计学意义（P〈0．05）；而26例无存活心肌的一组患者，上述指标在术前和术后差异无统计学意义（P〉0．05）。结论MI患者PCI前常规行NTG介入^99mTc-MIBI心肌显像对是否进行PCI治疗的病例选择有决策性指导作用。     

小剂量多巴酚丁胺负荷超声心动图结合多普勒组织成像评价存活心肌的研究

目的：研究多普勒组织成像（DTI）结合小剂量多巴酚丁胺负荷超声心动图评价心肌活性的可行性，并研究其与^99mTc-MIBI硝酸甘油介入心肌显像在评价存活心肌方面的一致性。方法：对30例经冠状动脉造影确冠心病的患者行超声心动图及心脏核素检查，超声心动图检查使用DTI速度模式，采用两级多巴酚丁胺超声心动图试验，所有患者均行静息显像及硝酸甘油介入后显像，结果：（1）30例冠心病患者用超声心动图静息DTI检测480个室壁节段，检出166个运动常节段，运动减弱节段108个，运动消失节段58个。（2）对患者行超声心动图小剂量多巴酚丁胺负荷试验DTI检测480个室壁节段，检出166个运动异常节段中89个节段运动改善，提示为存活心肌节段（A组）；余77个节段无变化，为坏死心肌（B组）。A组静息及负荷超声心动图DTI差异有显著性意义（P＜0．05），B组静息及负荷超声心动图DTI差异无显著性意义（P＞0．05）。A组与B组静息超心动图DTI差异无显著性意义（P＞0．05）。（3）30例冠心病患者用^99mTc-MIBI硝酸甘油介入心肌显像检测480个室壁节段，检出185个病变节段，其中97个为存活心肌节段，小剂量多巴酚丁胺结合超声心动图DTI诊断存活心肌的敏感性达83％，特异性达86％，结论：DTI结合小剂量多巴酚丁胺是评心肌活性的一项超声新技术，其结果与^99mTc-MIBI硝酸甘油介入心肌显像进行对照分析显示良好的一致性，应用前景较为乐观。     

DECT首过心肌灌注成像的临床应用

目的 探讨双源CT(DECT)心肌灌注成像的临床应用价值.方法 选取59例接受DECT心肌灌注成像及SPECT负荷心肌显像者,根据检查结果分为A组(对照组,20例)和B组(缺血性心脏病组,39例),测量A组各心肌节段以及B组灌注缺损区、缺损周边及缺损对侧心肌CT灌注值(VNC及Overlay值).比较DECT与SPECT检出早期心肌灌注缺损(EPD)的差异,分析冠状动脉狭窄程度对两种检查方法一致性的影响.结果 A组心尖部、中间部及基底部VNC、Overlay值的差异无统计学意义(P均＞0.05).B组中DECT检出92处EPD,其中53处经SPECT证实,二者检查结果的差异无统计学意义(x2 =3.403,P=0.065),呈中等相关(r=0.533,P＜0.01).供血冠脉轻度狭窄时两种检查方法检出EDP的差异有统计学意义(x2=11.396,P＜0.01),而中度及重度狭窄时两种检查方法检出EDP的差异无统计学意义(P均＞0.05).结论 DECT首过心肌灌注成像能准确评估正常心肌及缺血心肌的灌注情况,与SPECT检查结果具有相关性,且更易检出早期、轻度心肌缺血.     

慢性缺血性功能异常心肌血管重建术后跨壁收缩的背向散射研究

目的利用超声背向散射（IBS）技术研究慢性缺血性功能异常心肌在血管成功再灌注后跨壁收缩的变化特征。方法分别在血管重建术前、术后3d、术后6～8周，检测58例慢性冠心病伴有左室壁节段性功能障碍患者（共88个异常心肌节段，43个正常心肌节段）相关心肌节段心内膜下层心肌及心外膜下层心肌的IBS周期变化幅度（cycle variation of IBS，CVlB），并在常规超声下测量相应心肌节段的室壁增厚率（WT）。结果正常心肌节段心内膜下心肌CVIB明显高于心外膜下心肌CVIB（P〈0．001）。血管重建术前，慢性缺血性功能异常心肌节段心内膜下和心外膜下心肌的CVIB均减低，以前者为著，二者间无显著性差异（P=0．067）。成功再灌注后，心内膜下心肌CVIB恢复较心外膜下慢，出现“心内膜下顿抑”。术后WT的恢复与心内膜下心肌层CVIB的恢复相平行（r=0．816，P〈0．0001），而与心外膜下心肌CVIB的恢复无明显相关性（r=0．125，P=0．056）。结论CVIB可以无创检测心肌的跨壁收缩性。在慢性缺血心肌的再灌注恢复过程中，心内膜下心肌跨壁收缩性的变化与心脏收缩功能的恢复密切相关。     

多普勒能量组织成像定量左室缺血和梗塞心内膜面积

为探讨定量缺血和梗塞心肌的内膜面积新的可靠途径，用多普勒能量组织成像（DPTI）测量7条犬实验性急性左室缺血和梗塞心肌的内膜面积并和超声造影心肌灌注显像（MCE）、病理染色测量对照。结果表明：DPTI和MCE显示的缺血心肌的内膜面积无显著差异（P＞0．05），且高度相关（r=0．99，P＜0．01）；虽都大于病理染色显示的梗塞心肌的内膜面积（P均＜0．01），但均高度相关（r=0．78～0．82，P均＜0．01）。三种方法显示的左室内膜总面积无统计意义的差异（P均＞0．05）。因此可将DPTI作为定量缺血和梗塞心肌内膜面积的可靠方法。     

小心肌梗死的MRI诊断

目的：探讨小心肌梗死的MRI诊断价值;材料和方法：对12例心绞痛患者进行MRSE和MR电影成像,分析MRI表现与心肌核素显像（单光子发射计算机断层,SPECT）、冠状动脉狭窄和临床表现的关系;结果：12例心绞痛中MRI（T2WI和Gd－DTPAT1WI）发现5例有高信号的小心肌梗死灶（≤2cm）,与无高信号病冽（7例）相比,其心绞痛持续时间长、硝酸甘油效果差,冠状动脉狭窄严重,SPECT有明显局限性灌注缺损或稀疏区,心酶谱阳性率高,心电图有缺血表现（P＜0.05）;结论：MRI是检测小心肌梗死敏感而有效的方法。     

超声速度向量成像技术评价急性心肌缺血犬左心室心内膜下心肌力学状态

目的采用超声速度向量成像技术评价急性心肌缺血犬左心室收缩期心内膜下心肌力学变化规律。方法对12只健康比格犬结扎冠状动脉左前降支制作急性心肌缺血模型，采集缺血前后左心室二尖瓣口水平、乳头肌水平、心尖水平动态二维灰阶动态图像；获取左心室不同水平各节段缺血前后心内膜下心肌周向应变、径向应变、旋转角度与径向位移；分析同一节段心肌周向和径向应变与旋转角度的相关性，及两个相邻节段心肌周向应变差值（Acs）与相应节段心肌旋转角度和径向位移的相关性。结果缺血前左心室心内膜下心肌同一室壁周向应变、旋转角度从基底段到心尖段依次增大，缺血后这一力学状态发生改变，其中前间隔基底段周向应变大于心尖节段（P〈0．05），后间隔中段周向应变大于心尖节段（P〈0．05）；后壁基底段旋转角度大于中段（P〈0．01）、下壁中段旋转角度小于心尖节段（P〈0．05）、前间隔中段旋转角度小于心尖节段（P〈0．05）。缺血前心尖水平切面相邻两个节段心肌ACS与其相应节段心肌的旋转角度呈线性相关（r=0．609～0．739，P〈0．05或P〈0．01）；缺血前左心室心内膜下心肌同一室壁乳头肌水平节段与基底水平节段心肌△CS与其乳头肌节段心肌的径向位移呈线性相关（r=0．657～0．852，P〈0．05或P〈0．01），缺血后相关性消失。结论缺血前左心室心内膜下心肌相邻两个节段间的△CS与对应节段心肌旋转角度、径向位移的线性相关提示，相邻丽个节段心肌间的△CS与心尖节段旋转运动以及左心室心腔向心性收缩密切相关。急性心肌缺血状态下，左心室心内膜下心肌应变状态异常改变是左心室重构的重要力学基础。     

应用组织追踪和彩色多普勒冠状动脉血流显像结合多巴酚丁胺负荷试验评价缺血再灌注心肌的收缩储备和冠状动脉血流储备

目的应用组织追踪和彩色多普勒冠状动脉血流显像（CDCFI）结合多巴酚丁胺负荷试验分析不同时间的缺血再灌注对左室心肌收缩功能和冠状动脉血流的影响，以期为评估心肌存活性提供简便快捷的定量指标。方法健康杂种犬25条，随机分为顿抑组和梗死组。应用组织追踪和CDCFI技术观测顿抑组和梗死组缺血区（前间隔）于基础状态、再灌注30min以及再灌注90min多巴酚丁胺负荷前后二尖瓣环收缩期向心尖方向运动的最大位移（MVD）以及左前降支中远段舒张期冠状动脉血流储备（CFR）的动态变化。结果多巴酚丁胺负荷试验后，不同再灌注时间顿抑心肌和梗死心肌前间隔MVD的增加率（△D％）和左前降支的CFR值均明显低于基础状态（P〈0．001，P〈0．05），顿抑组的△D％以及CFR值均明显高于梗死心肌（P〈0．001，P〈0．05），并随再灌注时间延长，有逐渐好转趋势（P〈0．05，P〈0．05）；而梗死心肌则无此变化趋势（P〉0．05，P〉0．05）；CFR与二尖瓣环收缩期向心尖运动的最大位移变化率之间有良好的相关性（r=0．719，P〈0．05）。结论结合组织追踪技术和CDCFI技术动态观察缺血再灌注心肌多巴酚丁胺负荷后心肌收缩功能和冠状动脉血流动力学变化，可以提高判断存活心肌的准确率。     

不稳定型心绞痛患者全球急性冠状动脉事件注册评分与心肌灌注显像危险分层的相关研究

目的：研究不稳定型心绞痛患者^99mTc-甲氧基异丁基异腈（MIBI）负荷／静息门控心肌灌注显像危险度分层与全球急性冠状动脉事件注册（GRACE）评分的相关性。方法：2006年6月--2007年11月确诊为不稳定型心绞痛的住院患者37例。首先依据GRACE评分方法进行评分；然后行^99mTc-MIBI运动或腺苷负荷门控心肌灌注显像和静息心肌灌注显像，依据负荷／静息门控心肌灌注显像所测定的可逆性心肌缺血计分值（SDS）和负荷后左室射血分数（LVEF）将患者分为低危组和中危组。分析^99mTc-MIBI负荷／静息门控心肌灌注显像危险分层与GRACE评分的相关性。结果：37例患者均顺利完成^99mTc-MIBI运动或腺苷负荷门控心肌灌注显像和静息心肌灌注显像。低危组和中危组之间的GRACE评分有显著差异（P〈0．01）。GRACE评分与负荷状态下心肌缺血计分值（SSS）呈正相关（r=0．561，P〈0．01），与SDS呈正相关（r=0．623，P〈0．01），与静息状态下心肌缺血计分值（SRS）无关（r=0．175，P〉0．05）。结论：GRACE评分对不稳定型心绞痛患者的核素心肌灌注显像危险度分层有一定的预测价值。     

核素心肌灌注显像与多层螺旋CT血管成像对心肌桥的对比分析

目的探讨99 Tcm-MIBI心肌灌注显像对心肌桥的临床价值。方法回顾性分析105例冠状动脉CTA诊断为心肌桥并接受运动及静息99 Tcm-MIBI心肌灌注显像的患者资料,分析心肌灌注显像结果,并与冠状动脉CTA结果进行比较。结果 105例心肌桥患者中,根据Nobel分级法,Ⅰ级狭窄21例,Ⅱ级狭窄24例,Ⅲ级狭窄60例;其中60例出现心肌缺血改变。缺血组与非缺血组心肌桥患者冠状动脉CTA显示狭窄程度的差异有统计学意义(χ2=61.731,P<0.001)。不同部位心肌桥血管支发生异常灌注的差异无统计学意义(χ2=3.588,P=0.166)。结论 99 Tcm-MIBI心肌灌注显像能够用于评价冠状动脉心肌桥。     

应变率成像评价冠心病冠状动脉左前降支供血区心肌形变力及非同步性

目的应用应变率成像(SRI)技术对冠心病患者左室局部心肌形变能力及非同步性进行检测,探讨其在冠心病诊断中的应用价值。方法采用SRI技术对30例冠心病患者和30例正常人的冠状动脉左前降支供血心肌进行检测,测量收缩期应变率(SRs)及QRS波起始至SRs峰值的时限(Ts)、等容舒张期应变率(SRIVR)及QRS波起始至SRIVR峰值的时限(TIVR)。结果病例组左前降支供血的各相关心肌节段SRs明显降低,Ts明显延迟;病例组表现为负向等容舒张期应变率的节段数明显增多,其峰值明显高尖,TIVR时限延迟。结论SRI是一种无创性定量评价局部心肌形变能力及非同步性的新方法,对早期判断冠心病患者左室心肌收缩和舒张功能异常有重要价值。     

Integrated cardiac magnetic resonance imaging with coronary magnetic resonance angiography,stress-perfusion,and delayed-enhancement imaging for the detection of occult coronary artery disease in asymptomatic individuals

To evaluate the feasibility of using coronary magnetic resonance angiography (CMRA) with stress-perfusion and delayed-enhancement MRI as a screening tool for the detection of coronary artery disease (CAD) in asymptomatic subjects. Three hundred and forty-one self-referred asymptomatic subjects were enrolled in this study. Cardiac MR imaging was performed using a 1.5-T scanner with a 32-channel cardiac coil. Coronary artery stenosis, regional wall motion abnormalities, myocardial perfusion abnormalities, and delayed myocardial enhancement were analyzed. The occurrence of new chest pain and cardiac events was assessed in 332 subjects (97.3 %) over an average 29 ± 6 months (range, 18–39 months) follow-up period. A total of 3296 (82.4 %) of 4000 coronary artery segments examined exhibited diagnostic image quality on combined whole-heart and volume-targeted CMRA. Combined MRI detected significant CADs in 13 (3.8 %) of 341 subjects. Among these, 11 subjects (84.6 %) had both coronary artery stenosis (≥50 % by diameter) on CMRA and stress-perfusion defects in corresponding areas. Five of the 13 subjects showed evidence of old myocardial infarctions on delayed-enhancement MRI. Three subjects (0.9 %) underwent percutaneous coronary intervention after CAD was detected on cardiac MRI. There were no cardiac events during the follow-up period in subjects who complied with follow-up. Normal stress-perfusion and delayed-enhancement MRI lead to excellent outcomes when used to predict future cardiac events in asymptomatic subjects. Coronary MRA correlates well with stress-perfusion MRI for detecting significant CAD and helps exclude CAD in asymptomatic individuals.     

多巴芬酊胺超声心动图与心肌缺血

与冠脉造影及铊－２０１心肌ＳＰＥＣＴ显像对照研究疑冠心病患者２３例，评估多巴芬酊胺超声心动图在心肌缺血中的应用价值。结果表明多巴芬酊胺超声心动图检测冠脉狭窄及缺血后存活心肌的敏感度、特异度及符合率分别为７３％，７６％；７２％，８８％及７２％，８３％。评估左前降支供血节段缺血及缺血后存活心肌的能力较左旋支和右冠脉支供血节段强。     

Increased myocardial wall thickening as index of viability assessment: a preliminary report on delayed contrast MRI

Purpose : Regional wall thickening measurement by delayed contrast MRI may assess myocardial viability and functional recovery of ischemic cardiomyopathy. Materials and methods : Delayed contrast MRI data was used in 40 patients with significant coronary artery disease and severe left ventricular dysfunction. Regional wall thickening on follow‐up MRI served as an index of functional recovery in patients receiving revascularization. For comparison, myocardial viability was assessed by MRI and ²⁰¹Tl SPECT in 10 patients using a 17‐segment method. Results : On 480 segments, MRI hyperintensities showed positive correlation with ²⁰¹Tl reduction (r = 0.71, p < 0.0001) in the inferior wall and apex. Delayed MRI detected myocardial viability better than ²⁰¹Tl SPECT. Delayed contrast‐enhanced MRI showed diagnostic accuracy 65%, sensitivity 95%, specificity 25%, positive predictive value 65% and negative predictive value 75%, whereas ²⁰¹Tl SPECT showed diagnostic accuracy 54%, sensitivity 72%, specificity 25%, positive predictive value 52% and negative predictive value 54%. Areas under the ROC curves by MRI and ²⁰¹Tl SPECT were 0.59 ± 0.04, 0.52 ± 0.05, respectively (p = 0.07). The viability concordance was 80% between ²⁰¹Tl SPECT and MRI. Conclusion : Delayed contrast‐enhanced MRI may detect the inferior wall thickening and apex as an index of viable myocardium better than ²⁰¹Tl SPECT. Myocardial viability may predict functional recovery after revascularization in ischemic cardiomyopathy. Copyright © 2009 John Wiley & Sons, Ltd.     

Co-registration of cardiac MRI and rest gated SPECT in the assessment of myocardial perfusion, function and viability.

PURPOSE: Myocardial perfusion is routinely measured by SPECT--this technique has a rather low spatial resolution but covers the whole myocardium and is equipped with efficient image analysis software. Cardiac MRI has higher spatial resolution than SPECT and excellent sequences for myocardial function and viability detection but the lack of easy-to-use methods of acquisition and post-processing of perfusion images prevents this method from being used for perfusion evaluation in clinical practice. The aim of the study was to explore whether the 3-D co-registration of "cine" MRI (cine MRI), delayed enhancement MRI (DE MRI) and gated SPECT (GSPECT) images might be used for differentiating all reversible and irreversible effects of ischemia in anatomically matched myocardial regions. METHODS: We analyzed 685 segments of the heart (6 segments in each short axis slice)-obtained as a result of MRI and GSPECT studies performed in 18 patients. In each segment, myocardial function, perfusion and viability were analyzed. Myocardial wall function was evaluated using the matched images of diastolic and systolic phases of cine MRI. Perfusion as MIBI uptake per volume (MIV) (counts/mm3) in each myocardial segment was evaluated by co-registration of diastolic phases of cine MRI and GSPECT. Transmural extent of infarction was determined by co-registration of DE MRI and diastolic phase of cine MRI. RESULTS: We have found a close correlation between regional perfusion and function at rest in matched MRI and SPECT images: dysfunctional segments had significantly less MIV (MIV = 4.63 SD 1.58) than normal segments (MIV = 8.86 SD 2.77) (p < .05). There was no significant difference in MIV between viable and non-viable dysfunctional segments defined by DE MR due to a small number of nonviable segments in our study (18/685). CONCLUSION: Matching rest perfusion and function in anatomically co-registered myocardial segments in our study confirms that 3-D image co-registration of cine MRI, DE MRI and gated SPECT could be a precise method of integrated visualization of perfusion, function and viability helping in differentiating all forms of reversible and irreversible effects of myocardial ischemia.     

超声斑点追踪二维应变对冠心病患者左心室同步性的研究

目的 探讨超声斑点追踪二维应变检测冠心病左室心肌同步性的临床价值.方法 采用二维应变对33例冠心病患者及30例正常人的冠状动脉(冠脉)供血区域进行检测,测量自QRS波起始至收缩期纵向应变达峰时间间期(Ts)及左室18节段的Ts标准差(Ts-SD).结果 狭窄<75%冠脉供血节段共168个,狭窄≥75%冠脉供血节段共210个.①狭窄≥75%冠脉供血节段与正常对照组比较,绝大部分节段Ts明显延迟,Ts-SD明显升高;②狭窄≥75%冠脉供血节段与狭窄<75%冠脉供血节段相比,大部分节段Ts明显延迟,Ts-SD明显升高;③狭窄<75%冠脉供血节段与正常对照组比较,绝大部分节段Ts及Ts-SD差异无统计学意义;④以Ts-SD≥33.0 ms为左室收缩不同步,26例冠脉狭窄≥75%冠心病患者中22例(84.6%)收缩不同步,7例冠脉狭窄<75%冠心病患者中无收缩不同步.结论 当冠脉出现严重狭窄,在二维超声心动图上未能观察到室壁运动异常时,二维应变已能准确检测出其心肌运动不同步现象.     

Diagnostic accuracy of quantitative cardiac MRI evaluation compared to stress single-photon-emission computed tomography

Background: Cardiac MRI (cMRI) perfusion is a promising non-invasive tool to assess myocardial ischemia. The accuracy of quantitative cMRI perfusion has been recently demonstrated, but to date no previous study has compared this technique with stress single-photon-emission computed tomography (SPECT). The aim of this study was to evaluate the diagnostic accuracy of myocardial perfusion reserve (MPR) based on cMRI compared with SPECT. Methods: We examined 24 patients who underwent coronary angiography, stress SPECT and cMRI perfusion. Qualitative assessment of both SPECT and cMRI images, quantification of cMRI perfusion, and quantitative coronary angiography (QCA) were independently performed. MPR was calculated using Fermi deconvolution technique. Accuracy of quantitative and qualitative data was examined to detect > 50% diameter stenosis (DS) by QCA. Results: Qualitative analysis was obtained in 198 segments and quantitative analysis was performed in 171 segments. Significant coronary artery disease (CAD) was present in 81.8% of patients. Visual cMRI assessment yielded sensitivity of 74.4% and specificity of 79.4% to predict > 50%DS, while SPECT showed sensitivity of 67.4% and specificity of 81.3%. The sensitivity for SPECT in the right coronary artery territory and apex was low compared to cMRI. Sensitivity and specificity for detection of significant CAD were 89.5% and 46.6% for MPR (cutoff 1.92). Area under the curve was 0.75 for MPR (P < 0.01). Conclusions: The diagnostic accuracy of qualitative examination of perfusion cardiac MRI and stress SPECT were comparable. The high sensitivity and low operator dependency of quantitative cMRI makes it an attractive tool to evaluate myocardial perfusion.     

Scar detection by contrast-enhanced magnetic resonance imaging in chronic coronary artery disease: a comparison with nuclear imaging and echocardiography.

We compared contrast-enhanced MRI (CeMRI) with the most widely used imaging techniques for myocardial infarct (MI) diagnosis, SPECT and Echo, in unselected patients with chronic coronary artery disease (CAD). Two blinded operators assessed scars on MRI, SPECT and Echo images using a 16-segments LV model. We studied 105 consecutive patients: 50 had Q-wave MI (Q-MI), 19 non Q-wave MI or rest angina (nonQ-MI/RA) and 36 effort angina (EA) history. CeMRI was positive, respectively, in 96%, 37%, and 6%, SPECT in 90%, 53%, and 44%, and Echo in 84%, 32%, and 28% of patients (within Q-MI: CeMRI vs. SPECT p < 0.03, vs. Echo p < 0.001; within EA CeMRI vs. SPECT and ECHO p < 0.001; all trends p < 0.001, pseudo r-square: 0.56-0.75 for CeMRI, 0.18-0.28 for SPECT and 0.23-0.37 for Echo). CeMRI and SPECT agreed in 83 patients (79%); negative SPECT with 1 +/- 0 segments subendocardial delayed enhancement (DE) was found in 4 (4%); negative CeMRI with 4 +/- 3 segments perfusion defects in 18 (17%), 16 of whom were obese or showed LBB or sub-occlusion of related coronary. CeMRI and Echo agreed in 78 patients (75%); negative Echo with 2 +/- 1 segments subendocardial DE was found in 13 (12%) and negative CeMRI with 11 +/- 7 segments kinetic abnormalities in 14 (13%), in 10 confirmed by Cine-MRI. In Q-MI, CeMRI detects DE more frequently than perfusion defects and, especially, kinetic abnormalities are found by SPECT and Echo, respectively. CeMRI identifies small areas of DE also in some patients with nonQ-MI or RA but usually not in patients with EA. This biologically plausible decreasing trend is shown by CeMRI more clearly than by SPECT and Echo. Disagreement between CeMRI and SPECT or Echo may be reduced, but perhaps not fully eluded, performing dobutamine Echo and SPECT after maximal epicardial coronary dilatation.     

应变率成像评价缺血心肌收缩后收缩

目的应用应变率成像(SRI)技术评价健康者与冠心病患者局部心肌收缩后收缩(PSS),即等容舒张期负向应变率的特征及临床意义。方法对56例经冠状动脉造影确诊冠心病患者测量左心室缺血心肌收缩期应变率峰值(SRS)、等容舒张负向应变率峰值(SRPSS)、持续时间(TPSS)、出现SRPSS的节段数、收缩-舒张转换时间(Tcec)及SRPSS/SRS比值,并与56例健康对照组进行对比。结果缺血心肌与对照组比较SRPSS增大,出现SRPSS节段数增多,TPSS延长,Tcec延迟,差异有统计学意义。结论心肌收缩后收缩应变率能够较客观地检测出缺血心肌,并准确评价局部心肌功能。     

组织追踪成像评价冠心病患者心肌收缩期后收缩的特征

目的:采用组织追踪成像(tissue tracking imaging,TTI)评价冠状动脉(冠脉)疾病患者心肌收缩期后收缩(post-systolic shortening,PSS)的特征。方法:选取54例因胸痛住院行冠脉造影的患者,术前3 d接受TTI检查,并根据其冠脉造影结果分为对照组(28例)和冠脉狭窄组(26例)。PSS指标包括收缩期后位移(postsystolic displacement,Dpss)、收缩期后位移指数(post systolic displacement index,PSI)及PSS检出率。结果 :对照组和冠脉狭窄组患者的PSS检出率分别为19.5%和32.5%(P<0.05),冠脉狭窄组的Dpss和PSI平均值显著高于对照组(P均0.23为截点值,即24个节段中有≥6个节段检出PSS时,TTI预测冠脉狭窄的灵敏度为73.1%,特异度为71.4%。结论:TTI检查对于冠脉狭窄患者的PSS检出率较高,且PSS波峰较高大。TTI检查能显示PSS的特征,帮助诊断冠脉疾病。