The Value of Exercise Electrocardiography and Exercise Thallium-201 Myocardial Perfusion Scanning in Determining the Presence of Single Vessel Coronary Artery Obstruction

Summary: In 39 patients with single vessel coronary artery disease and no previous myocardial infarction, exercise thallium-207 myocardial perfusion scanning and 12 lead exercise electrocardiography (ECG) were compared to see how reliably each method identified the site of coronary artery obstruction. Significant (≥ 70% diameter) stenosis was present in the left anterior descending (LAD) coronary artery in 21 patients, in the right coronary artery (RCA) in 14 patients and in the left circumflex (LCX) in four patients. Thallium defects on the scan in the septa1 (SEPT), anteroseptal (ANT SEPT) and anterior (ANT) segments correlated (P < 0.0005) with LAD disease and defects in the inferior (INF), posteroinferior (POST INF), and posterior (POST) segments correlated (P < 0.0005) with RCA or LCX disease. Exercise induced ST segment elevation in VI and/or AVL correlated with LAD disease. The site of ischaemic ST depression did not correlate with disease in any vessel. ST segment depression in leads L2, 3, AVF (67%) and in leads V4–6 (67%) was most sensitive for detecting patients with LAD disease and ST depression in leads V4–6 was most sensitive (56%) for detecting patients with RCA or LCX disease but neither differentiated LAD from RCAILCX disease.
During exercise induced ischaemia, the site of ST segment depression on the 12 lead exercise ECG will not identify the area of ischaemia in patients with single vessel disease but thallium defects will. In contrast to ST depression, ST elevation in V1 and/or AVL may identify LAD stenosis.     

Serial Thallium-201 Myocardial Perfusion Scanning in Acute Myocardial Infarction*

Summary Serial myocardial perfusion scanning was performed in 30 patients with acute myocardial infarction. Scanning was commenced less than six hours after onset of symptoms in 12 patients, 6–24 hr in eight and 24–120 hr in ten. All 30 patients showed thallium defects corresponding to the ECG site of infarction. When initial and four-hour scans were compared, constant defects were present in ten patients and changing defects in 20. Of the 169 segments with defects on the initial scan, 117 (69%) remained constant, 41 (24%) improved, and 11 (7%) deteriorated. More defects changed in the patients scanned earlier (< 6hr) than in the patients scanned later (> 6hr) (42% vs 23% P < 0·025), and more defects changed in patients with subendocardial compared to transmural infarction (49% vs 26% P < 0·025). During a mean follow-up period of 18 months, seven patients died, two developed left ventricular failure, seven had angina and 14 remained asymptomatic. The non-survivors had significantly larger thallium defects than the survivors (55 ± 15% vs 37 ± 14%, P < 0·005). Serial change on thallium scanning was not related to the clinical course. Perfusion defects on serial thallium scanning are useful in detecting and localising early myocardial infarction and the size of defects is related to the subsequent clinical course. Changing perfusion defects on serial scanning suggesting peri-infarctional ischaemia are common, and make assessment of therapeutic interventions to limit infarct size difficult, but are not related to the clinical course.     

药物负荷核素心肌显像在特殊人群冠心病诊断中的应用

合并左束支传导阻滞、糖尿病的冠心病患者以及老年患者和绝经后女性患者,由于自身生理和病理的特殊性,冠心病临床确诊的准确性较低。在冠心病众多无创性检查方法中,药物负荷核素心肌显像以其准确性高的特点,被认为是在上述特殊人群中诊断冠心病较可靠的方法。     

Combination of Myocardial Perfusion Imaging and Coronary Artery Calcium Scanning: Potential Synergies for Improving Risk Assessment in Subjects with Suspected Coronary Artery Disease

For many years, the mainstay of noninvasive evaluation of patients suspected of ischemic cardiovascular disease (CVD) centered on the use of myocardial perfusion imaging (MPI). In recent years, the advent of newer modalities such as coronary artery calcium (CAC) scanning, coronary CT angiography, and MRI have broadened the means of assessing cardiac patients for this purpose. Moreover, the advent of these newer modalities has created potential synergies whereby combinations of tests may be clinically useful. In this review, we assess the potential synergies between MPI, whether assessed by single photon emission computed tomography (SPECT) or positron emission tomography (PET), and CAC scanning. Whereas MPI has long been used for diagnostic assessment and for risk stratification purposes, the emerging uses of CAC scanning now appear multifold: screening for CVD, triaging patients for diagnostic stress testing, improving risk stratification in patients following stress testing, and enhancing the direct management of patients’ CVD risk following CAC scanning. Recent work suggests that CAC scanning may be emerging as the initial test of choice for most asymptomatic patients. The advent of hybrid SPECT-CT and PET-CT scanners may signify an important new opportunity for the combined use of these modalities in the higher-risk asymptomatic patient population.     

Dynamic Myocardial Perfusion CT for the Detection of Hemodynamically Significant Coronary Artery Disease

ObjectivesIn this international, multicenter study, using third-generation dual-source computed tomography (CT), we investigated the diagnostic performance of dynamic stress CT myocardial perfusion imaging (CT-MPI) in addition to coronary CT angiography (CTA) compared to invasive coronary angiography (ICA) and invasive fractional flow reserve (FFR).BackgroundCT-MPI combined with coronary CTA integrates coronary artery anatomy with inducible myocardial ischemia, showing promising results for the diagnosis of hemodynamically significant coronary artery disease in single-center studies.MethodsAt 9 centers in Europe, Japan, and the United States, 132 patients scheduled for ICA were enrolled; 114 patients successfully completed coronary CTA, adenosine-stress dynamic CT-MPI, and ICA. Invasive FFR was performed in vessels with 25% to 90% stenosis. Data were analyzed by independent core laboratories. For the primary analysis, for each coronary artery the presence of hemodynamically significant obstruction was interpreted by coronary CTA with CT-MPI compared to coronary CTA alone, using an FFR of ≤0.80 and angiographic severity as reference. Territorial absolute myocardial blood flow (MBF) and relative MBF were compared using C-statistics.ResultsICA and FFR identified hemodynamically significant stenoses in 74 of 289 coronary vessels (26%). Coronary CTA with ≥50% stenosis demonstrated a per-vessel sensitivity, specificity, and accuracy for the detection of hemodynamically significant stenosis of 96% (95% CI: 91%-100%), 72% (95% CI: 66%-78%), and 78% (95% CI: 73%-83%), respectively. Coronary CTA with CT-MPI showed a lower sensitivity (84%; 95% CI: 75%-92%) but higher specificity (89%; 95% CI: 85%-93%) and accuracy (88%; 95% CI: 84%-92%). The areas under the receiver-operating characteristic curve of absolute MBF and relative MBF were 0.79 (95% CI: 0.71-0.86) and 0.82 (95% CI: 0.74-0.88), respectively. The median dose-length product of CT-MPI and coronary CTA were 313 mGy·cm and 138 mGy·cm, respectively.ConclusionsDynamic CT-MPI offers incremental diagnostic value over coronary CTA alone for the identification of hemodynamically significant coronary artery disease. Generalized results from this multicenter study encourage broader consideration of dynamic CT-MPI in clinical practice. (Dynamic Stress Perfusion CT for Detection of Inducible Myocardial Ischemia [SPECIFIC]; NCT02810795)     

运动-静息心肌灌注显像对冠心病病人心脏事件发生的预测价值

目的评价运动-静息心肌显像中不同显像方式及显像结果异常类型对心脏事件发生的影响。方法追踪了206例行运动-静息(SPECT)心肌灌注显像的病人,随访时间(1~56)个月,随访间期为(33.25±14.95)个月,出现心脏事件终止随访,未发生心脏事件者随访皆大于18个月。心脏事件包括心源性死亡、非致死性心肌梗死或梗死面积扩大及再血管化治疗。结果约206例在一周内经历运动-静息心肌显像,正常组133例,可逆性灌注缺损组20例,不可逆性灌注缺损组51例,心脏事件发生率分别为1.5%,65.0%,7.8%,经多样本率两两比较的χ2分割法分析可逆性灌注缺损灌注组心脏事件发生率与正常组和不可逆性灌注缺损组差别有统计学意义(P<0.01250),而后两组间无统计学意义(P>0.01250)。用Kaplan-Meier生存曲线分析3组累积未发生心脏事件率曲线,3组间差别有统计学意义(χ2=124.89,P<0.001),其中可逆性灌注缺损组预后最差;不同显像方式中,静息与运动方式均阴性或均阳性对心脏事件的发生有显著差异(χ2值分别为8.94和5.80,P<0.05)。结论运动-静息心肌灌注显像示可逆性灌注缺损是估测心脏事件发生的良好指标,运动显像阴性的病人心脏事件的发生率低于静息显像阴性者。     

腺苷负荷99m 锝-甲氧基异丁基异腈门控心肌灌注显像在冠心病诊断中的价值

目的:探讨腺苷负荷99m锝-甲氧基异丁基异腈(99mTc-MIBI)门控心肌灌注显像(G-MPI)诊断冠心病、评价冠状动脉(冠脉)病变及左心室功能的临床价值.方法:46例临床确诊或疑似的冠心病患者,分别行腺苷负荷99mTc-MIBI G-MPI及选择性冠脉造影检查,以冠脉造影为金标准,计算腺苷负荷G-MPI诊断冠心病及冠脉不同血管病变的敏感性、特异性及准确性,同时比较腺苷负荷99mTc-MIBI G-MPI的左心室射血分数(LVEF)与超声心动图的LVEF的相关性.结果:腺苷负荷99mTc-MIBI G-MPI诊断冠心病的敏感性为87.0%,特异性为81.8%,准确性为85.3%,阳性预测值为90.9%,阴性预测值为75.0%.它对判断冠脉各分支狭窄也具有较高的价值,其中左前降支敏感性为88.2%、特异性为81.8%、准确性为86.7%;左回旋支敏感性为78.6%、特异性为90.9%、准确性为84.0%;右冠脉敏感性为90.5%,特异性为72.7%,准确性为84.4%.而且,对冠脉病变支数的检出率分别为1支病变83.3%,2支病变91.7%,3支病变90.9%.腺苷负荷99mTc-MIBI G-MPI的LVEF与超声心动图的LVEF无显著差异,二者呈显著正相关(r=0.885,P=0.0001).结论:腺苷负荷99mTc-MIBI G-MPI对诊断冠心病、评价冠脉病变及左心室功能具有重要的临床价值.     

Exercise Testing and Thallium-201 Myocardial Imaging in Relation to Coronary Artery Disease in Patients with Severe Aortic Valve Disease*

Summary Thirty-three patients with aortic valve disease, fifteen with regurgitation, eleven with stenosis and seven with mixed disease, undergoing assessment for valve replacement which included adequate coronary angiography, were studied. A symptom limited graded treadmill exercise test was undertaken with administration of 40–70 MBq of ²⁰¹TI. Myocardial imaging was started within 15 minutes and repeated after four hours using a 37 PM tube Searle gamma camera. Myocardial images were read independently by three observers. Of the 33 sets of images, 21 were-ve, 5 + ve, 2 I (Indeterminate) and 5 D (Difference of opinion). Eight of the 33 patients had significant coronary artery disease (CAD) and of these three were scored + ve (all triple vessel). Two patients without CAD were scored + ve. Eight subjects developed angina during exercise testing, of whom four had CAD, and four with CAD did not develop angina. Historically, 13 of the 33 subjects had typical angina, six having CAD; an additional eight had other significant chest pain, two having CAD. In these subjects with severe aortic valve disease, exercise testing and myocardial imaging with ²⁰¹TI was of little value in detecting CAD. All patients with CAD gave a history of significant chest pain.     

Myocardial Perfusion and Viability Imaging in Coronary Artery Disease: Clinical Value in Diagnosis,Prognosis, and Therapeutic Guidance

Coronary artery disease is a leading cause of morbidity and mortality worldwide. Noninvasive imaging tests play a significant role in diagnosing coronary artery disease, as well as risk stratification and guidance for revascularization. Myocardial perfusion imaging, including single photon emission computed tomography and positron emission tomography, has been widely employed. In this review, we will review test accuracy and clinical significance of these methods for diagnosing and managing coronary artery disease. We will further discuss the comparative usefulness of other noninvasive tests—stress echocardiography, coronary computed tomography angiography, and cardiac magnetic resonance imaging—in the evaluation of ischemia and myocardial viability.     

99mTc－MIBI心肌灌注平面显像潘生丁试验在冠心病诊断中的价值

为了进一步证实９９ｍＴｃ－ＭＩＢＩ心肌灌注显像潘生丁试验对冠心病诊断的价值，我们采用国产ｒ照相机及计算机系统对４２例有胸痛症状的住院病人进行了９９ｍＴｃ－ＭＩＢＩ心肌灌注平面显像潘生丁试验和冠状动脉造影检查的对比研究。以冠状动脉造影结果分组，４２例受试者中２７例冠脉管腔有≥５０％的狭窄，男性２５例，女性２例，平均年龄５３．７０±８．５７岁。另外１５例冠脉造影正常，男性８例，女性７例，平均年龄５２．７３±１０．１０岁，作为正常对照组。潘生丁负荷为：０．７ｍｇ／ｋｇ×４ｍｉｎｉｖ，ＧＺＡ－１型ｒ照相机及计算机对心肌灌注显像图进行采集，平滑及灰阶开窗处理，由两名有经验的医师读片。结果表明：９９ｍＴｃ－ＭＩＢＩ心肌灌注平面显像对冠心病诊断的灵敏度为９６．３０％（２６／２７）；特异性为８０．００％（１２／１５）；对识别冠脉单支、双支、三支病变的灵敏度分别为１００％（１６／ｌ６）、８０．００％（４／５）和１００％（６／６）；全组共有４４支血管出现有意义的狭窄（≥５０％），心肌显像图上有３３支血管相应供血区出现放射性稀疏缺损，即检出病变血管的灵敏度为７５．００％（３３／４４）。对ＬＡＤ、ＬＣＸ、ＲＣＡ病变的检出率分别为９?     

心电图运动试验恢复期ST段改变诊断冠心病的价值

传统上以运动末ST段压低0．1mV作为诊断冠心病的阳性标准，但其诊断价值有限，长期以来心血管医师对恢复期ST段改变的临床价值都十分关注，但遗憾的是未被充分利用，近10年来，通过与冠状动脉造影比较发现运动试验后恢复期ST段改变有助于提高心电图运动试验诊断冠心病的敏感性及特异性，本文综述其研究进展。     

99mTc-MIBI心肌灌注断层显像与心电图对冠心病的诊断价值

目的评估^99mTc—MIBI心肌灌注断层显像与心电图（ECG）在冠心病（CAD）诊断的价值。方法对28例冠心病和可疑冠心病患者进行心电图检查和^99mTc—MIBI心肌灌注断层显像（同时采用半定量方法分析患者左心室心肌血流灌注情况），其中13例患者行冠状动脉造影术（CAG）。结果心肌灌注断层显像与ECG阳性率分别为42．9％、53．6％，两者阳性率间差异无显著性意义（P〉0．05）。ECG诊断冠心病的敏感性为3／3，特异性为3／10，阳性预测值为3／10，阴性预测值为3／3，准确度为6／13。心肌灌注显像诊断冠心病的敏感性为3／3，特异性为8／10，阳性预测值为3／5，阴性预测值为8／8，准确度为11／13。心肌灌注断层显像和ECG与CAG阳性率间差异均无显著性意义（P〉0．05）。结论^99mTc—MIBI心肌灌注层显像与心电图是安全、无创伤、方便及费用低的检查方法，临床联合应用对冠心病的诊断、治疗和预后判断有重要的价值。     

冠状动脉造影正常的心肌梗塞患者核素心肌灌注显像

目的 :分析冠状动脉造影正常的心肌梗塞患者核素心肌灌注显像表现。　　方法 :回顾总结了 18例冠状动脉造影正常的心肌梗塞患者 99m锝 -甲氧基异丁基异腈 (99m Tc- MIBI)静息心肌断层显像。　　结果 :18例心肌梗塞患者心肌灌注显像均显示异常 ,12例有节段性缺损 ,6例未见缺损但可见心肌节段性稀疏。心肌灌注显像对心肌梗塞的定位与心电图 Q波比较 ,显示病变部位更明确。　　结论 :心肌灌注显像提供了冠状动脉造影正常的心肌梗塞患者心肌损伤部位及程度。     

平板运动试验在冠心病诊断及预后评价方面的研究进展

平板运动试验作为一种无创检查手段,应用于冠心病诊断及预后评价,但传统的诊断标准敏感性及特异性较低。近年不断出现一些新的评价指标,现就评价指标的研究进展进行综述。