心肌血流灌注与室壁运动在评价冠状动脉疾病中的应用

目的　评价心肌血流灌注与室壁运动 (WM )对预测冠状动脉疾病 (CAD)的应用价值。方法　用间歇二次谐波脉冲反转显像技术 ,对 48例经冠状动脉造影证实的CAD患者行静脉心肌声学造影(MCE)。采用 16节段划分法 ,进行目测半定量心肌造影计分 (MCS) :回声均匀性增强 ,显影时间≤ 90s为1分 ;回声低淡不均匀 ,显影延时 (>90s)为 0 .5分 ;充盈缺损为 0分。室壁运动计分 (WMS) :运动正常、减弱、无运动及矛盾运动分别为 1、2、3、4分。结果　MCE、WM和两者联合应用预测CAD均具有高度的敏感性、特异性和准确性。MCE的敏感性和准确性均高于WM (均 P <0 .0 5)。联合应用MCE和WM的敏感性显著高于WM(P <0 .0 0 1) ,准确性也高于WM (P <0 .0 5) ,与MCE相比敏感性和准确性差异无显著性意义 (均P >0 .0 5)。 3种方法具有类似的特异性 (均P >0 .0 5)。MCS与WMS的等级相关r =-0 .58,P <0 .0 0 1。两者的符合率为 78%。结论　MCE、WM和两者联合应用预测CAD均具有高度的敏感性、特异性和准确性。MCE和MCE +WM预测CAD比WM更敏感和准确。局部心肌血流灌注与室壁运动有较好的符合率 ,且两者的异常程度也有一定的相关性 ,因此MCE WM相匹配的室壁节段比不匹配的节段更能反映是否存在冠状动脉狭窄     

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。     

急性心肌梗死患者脂蛋白（a）与冠状动脉病变程度的关系

目的探讨急性心肌梗死（AMI）患者血浆脂蛋白（a）[Lp（a）]与冠状动脉病变程度的关系。方法对136例AMI患者进行血脂检测及冠状动脉造影检查,按血浆Lp（a）水平分为低Lp（a）组（〈300 mg/L,46例）和高Lp（a）组（≥300 mg/L,90例）,比较两组血清Lp（a）浓度及冠状动脉病变特点的差异,应用logistic回归分析及逐步回归分析,观察以上指标与冠状动脉狭窄程度的相关性。结果高Lp（a）组Gensini积分、多支病变构成比例、梗死相关动脉（IRA）闭塞率分别为（145.6±36.2）分、58.9%、86.7%,高于低Lp（a）组（96.8±21.7）分、23.9%、56.5%;高Lp（a）组梗死相关动脉心肌梗死溶栓治疗试验（TIMI）积分为（1.58±0.88）分,低于低Lp（a）组的（2.31±1.07）分（P〈0.05）;回归分析发现,Lp（a）是冠状动脉病变程度I、RA闭塞率和TIMI评分的主要影响因素（P〈0.05或〈0.01）。结论 AMI患者血浆Lp（a）水平,与冠状动脉狭窄程度,IRA血流量、闭塞率及密切相关。     

慢性冠脉狭窄时局部心肌收缩功能与心肌血流的关系

目的评价慢性冠脉狭窄时心肌收缩功能与心肌血流（MBF）的关系,以探讨慢性可逆性左室收缩功能低下的发生机制。方法于左前降支（LAD）和左回旋支（LCX）近端以安放“水膨胀”式缩窄器的方法,建立13只慢性多支冠脉狭窄犬模型。二维超声评价室壁增厚率（%WT）,放射性微球定量心肌血流量（MBF）。结果术后第7dLAD和LCX供血区的平均%WT较术前均已降低（P<0.05）,但MBF在术后第21d才出现降低（P<0.05）。术后第7d26个（26/50）心肌节段表现为局部室壁运动异常（RWMA）;在15对配对的RWMA和非RWMA中,两者的MBF差异无显著性意义（P>0.05）;MBF与%WT间无明显相关（P>0.05）。然而术后第42d,在13对配对的RWMA和非RWMA中,RWMA的MBF均明显低于非RWMA（P<0.05）,且36个RWMA的MBF均与%WT有良好的相关性（P<0.0001）。结论慢性冠脉狭窄时,存活而收缩功能低下的心肌可伴或不伴MBF的降低,表明反复性心肌顿抑和心肌冬眠均在慢性可逆性左室收缩功能低下的发生中起作用。     

心肌血流储备分数在冠状动脉介入治疗术中的应用

目的：分析心肌血流储备分数（FFR）在冠状动脉介入治疗中处理临界病变策略制定的指导价值。方法：选择经冠状动脉造影（CAG）证实病变程度介于30％～70％的临界病变冠状动脉粥样硬化性心脏病患者24例,对靶血管行FFR检测,对FFR〈0．75的病变进一步行PCI治疗,FFR〉0．75的病变不予介入处理,所有患者均给予最优化药物治疗,3个月后随访患者心血管事件发生情况,进行心功能评价及复查血脂水平。结果：CAG提示46处临界病变,8例患者的11处病变行PCI治疗,治疗率为22％的,术后3个月总胆固醇水平较前明显降低,2例发生心绞痛事件,无1例发生心源性猝死或再次入院治疗。结论：在冠状动脉介入治疗中处理临界病变血管时,应用FFR测定辅助评估心肌供血,可以更合理的指导PCI。     

应激性高血糖与急性心肌梗死冠脉病变程度及预后的关系

目的:探讨应激性高血糖(SHG)与急性心肌梗死冠脉病变程度及预后的关系.方法:根据心肌梗死初期血糖将90例急性心肌梗死患者分为两组,A组血糖≥8mmol/L,B组血糖＜8 mmol/L.对两组冠脉造影结果及预后进行比较分析.结果:A组梗死相关血管近端病变、梗死相关血管为前降支或右冠、心力衰竭、严重心律失常和梗死后心绞痛例数明显多于B组(P＜0.05),而左室射血分数明显低于B组(P＜0.05).结论:急性心肌梗死合并SHG的梗死相关血管多为前降支或右冠近端病变,预后不好.     

ATP负荷MR心肌灌注成像对冠心病心肌缺血诊断的临床应用研究

目的 研究ATP负荷MR心肌灌注成像对冠心病心肌缺血诊断的临床应用价值。方法将临床通过DSA冠脉造影诊断为冠心病患者30例，无症状健康志愿者5例，进行ATP负荷MR心肌灌注成像，ATP负荷MR心肌灌注成像应用真正快速稳态梯度回波序列（fast imaging employ steady state quisition，FIESTA）用于观察心肌的运动，快速梯度回波序列（fastcard gradient echo train，FGRE ET）用于心肌灌注首过时相MPd图像采集。反转恢复梯度回波序列（myocardial delay enhancement，MDE）用于完成心肌灌注延迟30分钟后MRI图像采集。应用GE AW4．0工作站DCEMI（Dynamic Contrast Enhanced Myocardial Imaging）心肌灌注图像分析软件，对左心室短轴心肌灌注首过时相图像进行分析，得到心肌灌注时间—信号强度曲线，观察曲线的上升斜率和信号强度的峰值。根据Brandt等描述的左心室短轴位与冠状动脉血管分布的对应关系，确定存在狭窄的冠状动脉血管。冠脉造影使用日本岛津公司DAR1200双C臂DSA机，以冠状动脉管径≤50％作为有临床意义的狭窄的诊断标准。结果 通过ATP负荷MR心肌灌注成像测定心肌低灌注区信号强度以及时间-信号强度曲线上升斜率可以判定心肌缺血区域，判定结果与冠脉造影结果比较，其中25例结果一致，5例结果不一致，符合率为83％。结论 ATP负荷MR心肌灌注成像通过测定心肌信号强度以及时间—信号强度曲线上升斜率量化指标，对于冠心病心肌缺血诊断结果与DSA冠脉造影检查结果具有高度的一致性，ATP负荷MR心肌灌注成像是一种无创性的测定心肌的血流的检查方法，通过这种无创性综合的检测技术可以为临床提供有价值的信息，为临床诊断及恰当治疗提供可靠的依据。     

99mTc-MIBI心肌灌注显像与冠状动脉造影诊断冠心病的对比分析

目的：探讨99mTc-MIBI心肌灌注显像对冠心病的临床诊断价值。方法：128例住院患者，男76例，女52例。年龄30～85（56.5±12.5）岁。同时进行99mTc-MIBI心肌灌注显像与冠状动脉造影（CAG）检查，将结果进行相关性分析。对上述患者预后进行了抽样临床随访。结果：99mTc-MIBI心肌灌注显像与CAG均阳性65例，99mTc-MIBI心肌灌注显像阳性、CAG阴性32例，99mTc-MIBI心肌灌注显像阴性、CAG阳性22例，99mTc-MIBI心肌灌注显像与CAG均阴性9例。一种检查阳性和99mTc-MIBI心肌灌注显像与CAG均阴性预后良好。99mTc-MIBI心肌灌注显像与CAG均阳性，CAG证实主要冠状动脉狭窄≥75％预后较差。结论：99mTc-MIBI心肌灌注显像与CAG相辅相成，对冠心病患者的诊断、指导治疗决策和判断预后有重要临床意义。     

Combined magnetic resonance coronary artery imaging,myocardial perfusion and late gadolinium enhancement in patients with suspected coronary artery disease

Background

Cardiovascular Magnetic Resonance (CMR) imaging offers methods for the detection of ischemia and myocardial infarction as well as visualization of the coronary arteries (MRCA). However, a direct comparison of adenosine perfusion (PERF), late gadolinium enhancement (LGE) and MRCA or the results of their combination has not been performed. Aim of the study was to evaluate the feasibility/diagnostic performance of rest/stress perfusion, late gadolinium enhancement and MRCA and their combination in patients with suspected coronary artery disease (CAD) in comparison to invasive angiography.

Methods

Fifty-four patients (60 ± 10 years, 35 men, CAD 48%) underwent CMR including MRCA (steady state free precession, navigator whole heart approach, spatial resolution 0.7 × 0.7 × .0.9 mm, trigger delay and temporal resolution adjusted individually), stress PERF (adenosine 140 μg/min/kg), rest PERF (SSFP, 3 short axis, 1 saturation prepulse per slice) and LGE (3D inversion recovery technique) using Gd-BOPTA. Images were analyzed visually. Stenosis >50% in invasive angiography was considered significant.

Results

Mean study time was 68 ± 11 minutes. Sensitivity for PERF, LGE, MRCA and the combination of PERF/LGE and PERF/LGE/MRCA was 87%, 50%, 91%, 88% and 92%, respectively and specificity 88%, 96%, 46%, 88% and 56%, respectively. If image quality of MRCA was excellent (n = 18) the combination of MRCA/PERF/LGE yield a sensitivity of 86% and specificity of 91%. However, no test or combination improved diagnostic performance significantly compared to PERF alone.

Conclusion

In patients with CAD, the combination of stress PERF, LGE and MRCA is feasible. When compared to invasive angiography, adenosine stress perfusion outperforms CMR coronary angiography in direct comparison and yields the best results with non-significant improvement in combination with LGE and significant deterioration in combination with MRCA. MRCA may be of additional value only in a minority of patients with excellent image quality.     

Diabetes and coronary artery disease: the role of stress myocardial perfusion imaging

Stress myocardial perfusion imaging (MPI) has the potential not only to improve clinical outcomes in diabetic patients, but also to decrease unnecessary use of health care resources. However, before routine screening can be recommended, cost-effectiveness analyses are required to identify patients in whom such testing is appropriate. Nevertheless, MPI is clearly emerging as a valuable tool for improving management of coronary artery disease in all patients with diabetes mellitus.     

门控心肌灌注显像对孤立性心肌桥-壁冠状动脉患者的临床价值

目的：探讨门控心肌灌注显像（G-MPI）对孤立性心肌桥-壁冠状动脉（MB-MCA）患者的临床价值。方法：回顾性分析同期行G-MPI和CT冠状动脉造影（CTCA）患者,选择孤立性MB-MCA者进行分析。全部病例分成无症状组和症状组（包括胸痛组和非胸痛组）,以G-MPI诊断结果为心肌缺血或心肌梗死作为心肌灌注异常阳性标准,计算并比较G-MPI检测各组孤立性MB-MCA导致心肌灌注异常的阳性率。结果：符合入选标准的孤立性MB-MCA者共89例,其中G-MPI阳性者4例（均为心肌缺血）,阳性率为4.5%（4/89）;无症状组、非胸痛组和胸痛组G-MPI阳性率分别为0（0/31）、0（0/37）和19.1%（4/21）,与其他组相比,胸痛组G-MPI阳性率较高（P<0.05）。结论：孤立性MB-MCA者导致心肌灌注异常的比例不高,心肌灌注显像能明确该病是否引起心肌缺血,为临床提供客观依据,以避免不必要的治疗。     

无创性冠状动脉血流储备评价冠状动脉前降支病变心肌缺血

目的 探讨ATP负荷经胸多普勒超声心动图法(TTDE)无创性测量冠脉血流储备(CFR)评价冠脉左前降支病变心肌缺血、预测冠脉狭窄的临床价值.方法 选取胸痛发作、已知或疑似冠心病的左前降支单支病变患者54例,在TTDE冠脉血流显像模式下,于ATP注射前、注射中和注射后分别获取左前降支远段血流频谱,测定其静息时及最大冠脉扩张时峰值流速,计算CFR.进行冠脉造影(CAG)及单光子发射计算机断层成像术(SPECT)检查.结果 ①与SPECT心肌灌注显像对照,无创性CFR法评价心肌缺血差异无明显统计学意义(P＞0.05).CFR≤2.0评价左前降支病变相应供血区域心肌缺血的敏感性为93.3％,特异性为89.7％.②冠脉狭窄与CFR呈负相关(P＜0.001),随着狭窄程度加重,CFR逐渐减低.绘制ROC曲线,以CFR≤1.60为截断值预测冠脉显著狭窄的敏感性和特异性分别为92.3％和73.3％.结论 ATP负荷TTDE法CFR是评价冠心病心肌缺血的敏感指标并可以预测冠脉显著狭窄;CFR与CAG联合对稳定型冠心病治疗方案的选择具有重要临床价值.     

经静脉心肌超声造影对犬冠状动脉阻断后心肌灌注动态变化的研究

目的　探讨自制超声造影剂经静脉心肌造影对犬冠状动脉阻断后不同时间灌注缺损面积对梗死面积评价的准确性。方法　应用超声处理仪振荡 5 %白蛋白和低分子右旋糖酐混合溶液 ,加入全氟丙烷 (C3 F8)气体自制超声造影剂 ;选择左心室乳头肌短轴观 ,对 12条犬于冠状动脉阻断前、阻断即刻和阻断后 1～ 4h进行经静脉心肌造影超声心动图研究。结果　阻断即刻的最大灌注缺损面积 (DA)占左心室乳头肌短轴观左心室壁心肌总面积百分比 (DA % )为 2 3 .0 1± 5 .3 3 ,阻断后 1～ 4h ,最大DA %与阻断即刻比较差异无显著性意义 (P >0 .0 5 )。阻断后最小DA %随时间发生变化 ,阻断即刻、阻断后 1、2、3、4h的最小DA %分别为 2 2 .19± 6.2 1,16.2 6± 3 .88,6.2 4± 2 .48,7.97± 2 .78和 8.80± 3 .45 (P <0 .0 1)。阻断后2～ 4h最小DA %与病理上梗死面积 (IA )占相应断面左心室心肌总面积百分比 (IA % )相关 ,r分别为0 .76,0 .80和 0 .85。结论　冠状动脉阻断后 ,心肌造影上最大灌注缺损面积无显著变化 ,而最小灌注缺损面积随时间变化 ,在阻断一定时间后 ,最小灌注缺损面积反映梗死面积。     

Implications of transient ischemic dilatation and impaired left ventricular ejection fraction reserve in patients with normal stress myocardial perfusion imaging and elevated coronary artery calcium

The International Journal of Cardiovascular Imaging - Guidelines recommend stress only (SO) myocardial perfusion imaging (MPI) without follow-up rest imaging if perfusion and left ventricular...     

实时心肌超声造影结合二维应变评价冠状动脉搭桥术后心肌灌注与收缩功能的改变

10.45±8.31)%,P<0.05],而心肌灌注无改善节段组无明显变化[(-10.33±6.53)%对(-9.41±6.09)%,P>0.05].结论 冠状动脉搭桥术后心肌灌注改善与否可以反映心肌功能恢复的趋势,而二维应变能够动态观察局部心肌功能变化,联合运用两种技术能够更准确地评价冠状动脉搭桥术的治疗效果.     

Assessment of coronary stenoses of graded severity by myocardial contrast echocardiography.

BACKGROUND: Myocardial contrast echocardiography (MCE) has potential value in the assessment and quantitation of myocardial perfusion defects. However, the severity of stenosis detectable by MCE and its diagnostic accuracy remain undefined. Thus, we produced coronary stenoses of variable severity and quantified their effect on MCE. METHODS AND RESULTS: Three grades of left anterior descending (LAD) obstructions were produced in 7 open-chest swine. The stenoses were nonflow-limiting at rest, but decreased coronary hyperemia by 31.3% +/- 4.7%, 69.9% +/- 5.3% and 98.9% +/- 1.1%, respectively. Regional myocardial blood flow (RBF) was measured with fluorescent microspheres and was expressed as the ratio of LAD and control (LCx) beds. MCE was performed with 0.3 mg/kg intravenous AF0150 during ECG-gated harmonic imaging in short-axis view. Background-subtracted peak intensity (PI) was expressed as the ratio of LAD/LCx beds. Both RBF and PI ratios progressively decreased with increasing grades of stenosis. MCE showed a significant correlation with RBF (r = 0.74; P <.0001). Ratios of both PI and RBF differed significantly from baseline when coronary hyperemia was reduced more than 50%. An LAD/LCx ratio less than 0.6 by MCE yielded 61% and 83% sensitivity and 85% and 76% specificity with stenosis that reduced coronary hyperemia more than 50% and more than 75%, respectively. CONCLUSION: MCE with intravenous AF0150 during vasodilation correctly depicted the progressive reduction of flow ratios produced by graded coronary stenoses. A significant reduction of PI ratio was observed with stenosis causing more than 50% reduction of coronary hyperemia. An MCE ratio in stenosed/control beds could be selected, which exhibited good sensitivity and specificity in the identification of coronary stenosis.     

双源CT冠状动脉血管成像评价心肌桥与冠状动脉粥样硬化性病变的关系

目的：双源CT冠状动脉血管成像评价心肌桥与冠状动脉粥样硬化性病变的关系。材料与方法：对767例疑冠心病患者进行双源CT冠状动脉血管成像。计算心肌桥的发生率,测量心肌桥长度、深度、确切的部位及合并冠状动脉粥样硬化改变。比较单纯心肌桥组与合并冠状动脉硬化组之间的关系。结果：767例中,发现心肌桥-壁冠状动脉401例（52.3%）,左前降支是最常见的部位（344/401）,左前降支心肌桥组和无心肌桥组近侧冠状动脉粥样硬化比较,有显著统计学意义（P<0.0001）,其中轻度P<0.0001,中度P<0.02,重度P<0.0001。左前降支心肌桥近侧狭窄与心肌桥的厚度有关,与长度无关。结论：心肌桥近侧冠状动脉硬化发生率高,表明心肌桥是冠状动脉病变解剖学上的危险因素。