CT 测量心外膜脂肪组织体积与冠状动脉斑块的关系

目的：CT测量心外膜脂肪组织(EAT)体积与冠状动脉粥样硬化斑块的关系。方法141例疑似冠心病患者行多层螺旋 CT 造影检查,精确测量相应 EAT 体积。(1)根据造影检查结果确定冠状动脉粥样硬化斑块的有无和类型,分别进行斑块组与非斑块组,钙化斑块组、混合斑块组、非钙化斑块组,心外膜脂肪体积的比较。(2)按照不同性别分组,比较斑块组与非斑块组 EAT体积的差异。(3)依据年龄不同分组,比较斑块组与非斑块组在不同年龄段 EAT 体积的差异。结果冠状动脉有斑块63例,其中钙化斑块15例,非钙化斑块20例,混合斑块28例;无斑块78例。斑块组 EAT 体积大于非斑块组,两者之间存在统计学差异(P <0.05)。不同性质斑块之间 EAT 体积差异无统计学意义。EAT 体积在斑块组和非斑块组均为女性高于男性,但差异无统计学意义。按年龄分组后,各年龄组内 EAT 体积均为斑块组大于非斑块组,但只有在65岁后,差别存在统计学意义。结论EAT 体积与冠状动脉粥样硬化斑块形成存在较强的相关性,在65岁后表现的更加明显。相关性不受性别影响。     

核素显像心肌灌注缺损与CTCA冠状动脉不同狭窄程度的关系分析

目的通过分析核素显像心肌灌注缺损与CTCA示冠状动脉（简称冠脉）不同狭窄程度间的关系,探讨和评价CTCA预测心肌灌注缺损的诊断效能。方法回顾性分析同期行CTCA和MPI患者478例。按目测法将CTCA所示冠脉管腔狭窄程度分成无狭窄、轻度狭窄、中度狭窄、重度狭窄和管腔闭塞,将MPI结果分成灌注正常和灌注缺损,分别在病例和血管水平统计各组灌注缺损的发生率。以MPI为参考标准,将CTCA预测心肌灌注缺损的冠脉狭窄程度判定界值设为≥50％或≥75％,在病例水平和血管水平上确定该方法的诊断效能。计数资料统计分析采用χ^2检验、χ^2分割法和Fisher确切概率法。结果478例患者中58例出现MPI灌注缺损。无论按病例水平还是血管水平分析,各组灌注缺损发生率有随冠脉狭窄程度增加而升高趋势（χ^2=116．62和483．83,P均〈0．05）。在病例水平上分析,当判定界值为≥50％或≥75％时,CTCA预测心肌灌注缺损的诊断灵敏度、特异性、阳性预测值、阴性预测值、准确性分别为62．1％（36／58）或34．5％（20／58）（χ^2=8．84,P〈0．05）、84．5％（355／420）或97．1％（408／420）（χ^2=40．16,P〈0．05）、35．6％（36／101）或62．5％（20／32）（χ^2=7．19,P〈0．05）、94．2％（355／377）或91．5％（408／446）（χ^2=2．18,P〉0．05）、81．8％（391／478）或89．5％（428／478）（χ^2=11．66,P〈0．05）;在血管水平上分析,判定界值为≥50％或≥75％时,CTCA预测心肌灌注缺损的诊断灵敏度、特异性、阳性预测值、阴性预测值、准确性分别为58．8％（40／68）或30．9％（21／68）（χ^2=10．73,P〈0．05）、95．9％（1768／1844）或99．0％（1826／1844）（χ^2=36．72,P〈0．05）、34．5％（40／116）或53．8％（21／39）（χ^2=4．59,P〈0．05）、98．4％（1768／1796）或97．5％（1826／1873）（χ^2=4．14,P〈0．05）、94．6％（1808／1912）或96．6％（1847／1912）（χ^2=10．31,P〈0．05）。结论心肌灌注缺损的发生率随冠脉狭窄程度增加有升高趋势。CTCA预测心肌灌注缺损的诊断特异性和阴性预测值较佳。当判定界值为≥75％时,其阳性预测值较判定界值为≥50％时有明显提高。     

Relation between quantitative coronary CTA and myocardial ischemia by adenosine stress myocardial CT perfusion

Journal of Nuclear Cardiology - Coronary-computed tomography angiography (CTA) has limited accuracy to predict myocardial ischemia. Besides luminal area stenosis, other coronary plaque morphology...     

Mental stress-induced myocardial ischemia in coronary artery disease patients with left ventricular dysfunction

Background  Reduced left ventricular ejection fraction (LVEF) is a risk factor for poor outcomes in patients with coronary artery disease (CAD). Mental stress-induced myocardial ischemia (MSIMI) also identifies a subset of CAD patients at increased risk for future cardiovascular events. Susceptibility to MSIMI in patients with CAD and reduced LVEF is unknown. Methods and Results  We enrolled 182 patients (67 women) with a mean age of 64 years and a documented history of CAD in this study. Baseline resting ejection fraction was determined by use of technetium 99m sestamibi gated single photon emission computed tomography. Abnormal LVEF was defined as less than 45% for men and less than 50% for women (based on published norms for our software [Cedars-Sinai Medical Center]). All participants underwent mental stress testing with a public speaking task. Rest/stress myocardial perfusion single photon emission computed tomography was performed via conventional methodology. Images were visually compared for number and severity of perfusion defects by use of a scoring method from 0 to 4. A summed difference score was calculated as the difference between summed stress and rest scores. A score of greater than 3 was considered abnormal. MSIMI developed in 19% of patients with normal LVEF and 31% of those with reduced LVEF. There is no statistically significant difference between the two groups (P=.11). Conclusions  CAD patients with left ventricular dysfunction are equally susceptible to MSIMI as those with normal LVEF. This study was supported by grants HL 070265 and HL 072059 from the National Heart. Lung, and Blood Institute. This material is also the result of work supported by resources and with the use of facilities at the Department of Veterans. Affairs Medical Center, Gainesville, Fla.     

128层CT探讨心肌桥-壁冠状动脉与冠脉动脉粥样硬化的关系

目的:探讨心肌桥-壁冠状动脉(myocardiac bridge and mural coronary artery,MB-MCA)检出率及MB-MCA与动脉动脉粥样硬化的关系。方法:回顾性分析455例冠状动脉的MSCT资料。在薄层横断面图像基础上,主要通过分析CPR、VR图像判断MB-MCA。评估右冠状动脉、左前降支和左旋支3支的近、中、远段,以及MCA本身及其近、远侧段血管有无动脉粥样硬化钙化斑块、钙化积分评分、软斑块及其狭窄情况。结果:检出MB-MCA者的各支冠脉动脉粥样硬化钙化斑块和软斑块主要累及近段,较未检出MB-MCA者中段、远段增多且差异具有统计学意义(P均0.05)。MB近侧动脉粥样硬化斑块检出率显著多于MCA本身和其远侧(P0.001)。结论:MB-MCA并不会促进动脉粥样硬化的发生和进展,反而在某种程度上降低其发生的风险。     

The relationship between coronary artery calcification detected by non-gated multi-detector CT in patients with suspected ischemic heart disease and myocardial ischemia detected by thallium exercise stress testing

OBJECTIVE: To examine whether we could predict myocardial ischemia when coronary artery calcification is detected by non-gated multidetector CT in patients with suspected ischemic heart disease. METHODS: Eighty-three patients suspected of having ischemic heart disease (55 men, 28 women; age range 36-83 years; mean age 68 years) underwent multidetector CT and T1-201 single photon emission computed tomography. Prediction of myocardial ischemia by coronary arterial calcification detected on CT was evaluated by comparing the coronary artery territories that showed calcification with the area of myocardial ischemia determined by SPECT. The sensitivity, specificity, positive predictive value, and negative predictive value of multidetector CT for predicting myocardial ischemia were calculated. Coronary angiography was also examined and compared with multidetector CT. Risk factors, including hypertension, smoking, hyperlipidemia, diabetes, and family history, were compared for evidence of coronary artery calcification detected by multidetector CT and myocardial ischemia detected by thallium nuclear scans. RESULTS: For analysis by patients, the sensitivity, specificity, positive predictive value, and negative predictive value of coronary artery calcification for myocardial ischemia detection were 65, 63, 56, and 71%, respectively. Similarly, for analysis by coronary arterial territories, those values were 56, 77, 41 and 86%, respectively. Coronary stenosis on CAG was also related to the ischemia determined by SPECT and calcification on multidetector CT. Ischemia was better influenced by risk factors than was coronary arterial calcification. CONCLUSIONS: For analysis by coronary arterial territories, the specificity and negative predictive value of coronary arterial calcification seen by multidetector CT are relatively high.     

SPECT／CT显像评价“功能相关冠状动脉病变”的价值

目的探讨SPECT／CT显像评价“功能相关冠状动脉（简称冠脉）病变”的可行性及临床价值。方法40例可疑或确诊冠心病患者同机完成^99Tcm-甲氧基异丁基异腈（MIBI）负荷／静息心肌灌注断层显像和冠脉CT造影（CTCA）。负荷／静息心肌灌注显像采用标准二日法,首日行腺苷负荷心肌灌注显像,次日行静息心肌灌注显像及CTCA。腺苷按患者体质量以0．84mg·kg^-1·min^-1经静脉泵匀速给药,CTCA使用标准自动对比剂跟踪扫描程序完成。通过专用融合软件将心肌血流灌注与冠脉三维成像图融合,评价心肌缺血与冠脉病变的相关关系,确定“功能相关冠脉病变”。结果40例患者,CTCA正常20例,异常20例;120支冠脉中共检出33支病变血管,累及左前降支15支,左回旋支9支,右冠脉9支。心肌灌注显像正常22例,心肌缺血和（或）心肌梗死18例。SPECT心肌灌注和CTCA融合图像显示供血区心肌血流灌注正常且无狭窄冠脉占总的无狭窄冠脉的92．47％（86／93）,狭窄〈75％的冠脉中,其供血区心肌缺血或梗死的阳性率占42．86％（6／14,例）,狭窄〉75％或闭塞冠脉中,其供血区心肌缺血的阳性率占92．31％（12／13,例）。120支冠状动脉中20．83％（25／120,支）的病变冠脉为“功能相关冠脉病变”,检测出27例患者中25．93％（7／27,例）有无狭窄病变的冠脉导致心肌缺血;使15．38％（2／13,例）冠脉病变患者免除有创性诊断检查;指导对42．86％（6／14,例）的狭窄〈75％冠脉行药物治疗或冠脉血管重建术治疗;为1支狭窄〉75％的冠脉无需行血管重建术提供依据。结论SPECT／CT心肌灌注和CTCA融合显像可确定“功能相关冠脉病变”,可提供综合信息诊断冠心病和指导治疗。     

SPECT/CT显像评价"功能相关冠状动脉病变"的价值

Objective There is great interest in the assessment of functionally relevant coronary artery lesions and its value in coronary artery disease (CAD) management by hybrid SPECT/CT.The obiective of this study was to evaluate the clinical value and the feasibility of imaging of hybrid SPECT/CT in detecting the"funotionally relevant coronary artery lesions(FRCAL)".Methods Forty patients with suspected or known CAD performed computed tomography coronary angiography (CTCA) and stress/rest myocardial perfusion imaging(MPI)with 99Tcm-methoxyisobutylisonitrile (MIBI) by hybrid SPECT/CT..Stress/rest MPI was performed with standard two-day protocol,and CTCA was performed the second day.performed with standard contrast medium autotrack sequence.Images of MPI and CTCA were fused by special fusion software (AutoQUNANT 7.0) in order to evaluate the funotional relationship between myocardial isehemia and CAD,videlicet"FRCAL".Results Twenty of the 40 patients had coronary atherosclerosis,malformation or coronary stenosis,with a total of 33 diseased coronary vessels(15 left anterior descending coronay artery,9 left circumflex coronary artery and 9 right coronary artery).The remaining 20 patients had normal results.MPI were normal in 22 and 18 showed myocardial ischemia and (or) infarct.The ratio of normal MPI in normal CTCA was 92.47%(86/93) by SPECT/CT imaging.The positive rates of detecting isehemia were 42.86% (6/14,＜75% diameter stenosis) and 92.31% (12/13,＞75% diameter stenosis or blockage).About 20.83% (25/120) of all the narrowed coronary arteries determined to be"FRCAL"and 25.93% (7/27) of the patients without coronary stenosis had myocardial ischemia.And then 15.38% (2/13)of the patients with CAD avoided invasive procedures (that was coronary angiography).About 42.86%(6/14) needed drug treatment or coronary revascularization(＜75% diameter stenosis).There was 1 patient with 1 vessel＞75% diameter stenosis but no coronary revascularization.Conclusion Fusion imaging of MPI and CTCA by hybrid SPECT/CT has clinical values in diagnosing CAD and selecting the"FRCAL"patients who might benefit from further revascularization procedures.     

Unfolded map of coronary artery territories by myocardial SPECT

Coronary artery territories were evaluated precisely by Bull's-eye and unfolded map generated from myocardial SPECT. In addition, unfolded maps including apical information were also developed. The coronary artery territories were determined by 54 cases of typical single vessel disease (more than 75% stenosis) with myocardial infarction and angina pectoris. There were 12 of right coronary artery disease, 24 of left anterior descending coronary artery disease, 5 of diagonal coronary artery disease, and 13 of left circumflex artery disease. Each diseased region was summed and normalized using the standard pattern (21 cases of normal male and 13 cases of normal female). Apical information was simply obtained using the anterior and posterior count from short and long axial image. Then, their data were added to the unfolded map. In conclusion, unfolded map was proven to be useful for the determination of coronary artery territory, since this map expressed the extent and site of myocardial damage precisely compared to Bull's-eye. The unfolded map to contain the apical information was also useful for the evaluation of left anterior descending coronary artery involvement.     

CCTA评价冠状动脉狭窄程度与SPECT心肌灌注显像关系的研究

目的：探讨冠心病患者CCTA不同狭窄程度与SPECT MPI间的关系。方法68例患者进行了CCTA和MPI检查,所有患者均行冠状动脉造影。CCTA按管腔狭窄程度分为5个级别,即0,1%~24%,25%~49%,50%~74%,75%~100%。MPI分为正常和灌注缺损(包括可逆缺损和不可逆缺损)。结果68例患者共204根血管纳入分析。以患者为单位进行分析,40例CCTA显示管腔重度狭窄的患者中,29例(72.5%)MPI显示灌注缺损。另外11例(27.5%)CCTA异常的患者心肌灌注 MPI显示正常。在28例CCTA显示未见明显狭窄的患者中,17例(60.1%)显示心肌灌注正常,而另外11例(39.9%)显示灌注缺损。根据CCTA冠状动脉狭窄程度分组,心肌灌注缺损(包括不可逆性灌注缺损和可逆性灌注缺损)出现的比率：0,1%~24%,25%~49%,50%~74%,75%~100%分别为5(27.7%)/18,1(33.3%)/3,5(71.5%)/7,4(50%)/8,25(78.1%)/32。结论冠状动脉狭窄和灌注缺损的不匹配多发生在冠状动脉中度狭窄的患者。在轻度狭窄和重度狭窄的患者中,二者多匹配。冠状动脉中度狭窄的患者应进行CCTA和 MPI联合检查评价冠心病。     

腺苷负荷99mTc-MIBI心肌SPECT/CT显像诊断冠心病及检测存活心肌的研究

 目的 评价国产腺苷负荷心肌灌注断层显像对心肌缺血的诊断及腺苷试验的安全性.方法 60例临床疑似冠心病的患者行腺苷负荷99mTc-MIBI(甲氧基异丁基异腈)心肌灌注断层显像,其中40例行冠脉造影检查.腺苷按0.84 mg/kg通过输液泵静脉双通路给药,对心肌灌注显像图作定性分析.结果 60例患者行冠脉造影者40例,其中正常8例,1支以上狭窄≥50%者32例,其中病变为单支11例,双支14例,3支7例.60例行腺苷负荷心肌灌注显像检查总阳性率为80%(48/60).腺苷试验不良反应轻时间短,发生率为80%(48/60).结论 腺苷负荷心肌灌注显像安全可靠.     

Relationship between silent myocardial ischemia and coronary artery disease risk factors

Background

The association between silent myocardial ischemia (SMI) and coronary artery disease (CAD) risk factors in asymptomatic patients with no prior history of CAD referred for stress myocardial perfusion imaging (MPI) is unknown.

Methods

We retrospectively evaluated patients who underwent MPI over a 3.4-year period to identify those who did not have chest pain, dyspnea, or known CAD. The presence of risk factors was categorized as none, 1-2, 3-4, and ≥5. MPI was performed using a rest thallium-201/stress Tc-99m sestamibi protocol, and read using a standard five-point perfusion score (0 = normal to 4 = absent) and a 17-segment left ventricular model. Summed stress score and summed rest score were derived as the sum of individual segmental scores at stress and rest, respectively. SMI was diagnosed if the summed differences score (SDS) was ≥2. Prognostically significant ischemia was defined by a SDS ≥ 8.

Results

Among 1,354 asymptomatic patients, SMI was present in 97 (7.2%) and prognostically significant in 60 (4.4%). The prevalence, but not severity, of SMI increased with increasing CAD risk factors—0 for none, 4.1% for 1-2, 8.8% for 3-4, and 12% for those with ≥5 CAD risk factors (P value for trend = .001), in patients <74 years of age. Of the 59 (4.4%) patients who underwent coronary angiography, only 31 (2%) had significant anatomical CAD.

Conclusions

The prevalence of SMI and prognostically significant ischemia is low in asymptomatic patients without known CAD, and is related to the number of CAD risk factors in patients younger than 74 years of age.     

Diagnostic pathway of integrated SPECT/CT for coronary artery disease

Treatment strategy in patients with suspected coronary artery disease (CAD) is driven by symptomatology in combination with diagnostic evaluation of the extent and/or severity of atherosclerosis in the coronary arteries and ischemia in the myocardium, i.e., the anatomic and functional correlates of CAD. Whereas multislice row computed tomography (MSCT) has the advantage of detecting coronary atherosclerosis at its earliest stages, thereby allowing initiation of appropriate therapeutic measures well before development of obstructive CAD, myocardial perfusion imaging (MPI) SPECT can clarify the hemodynamic consequences of the anatomic findings on MSCT based on a functional assessment of myocardial blood flow. There is a lack of correlation between coronary artery calcium (CAC), coronary artery stenosis, and MPI SPECT. Therefore CAC scoring and stress MPI should be thus considered complementary approaches rather than exclusionary in the evaluation of the patient at risk for CAD. The integration of anatomic and functional information may provide additional information for the clinician by the improved risk stratification and diagnostic accuracy of integrated techniques. The majority of previous studies are based on a sequential flowchart, starting with either SPECT or CAC scoring that finally directs the therapeutic strategy. Patients at low risk for CAD can be selected for primary prevention, and patients at high risk for CAD can be directly selected for coronary angiography (CAG). The remaining group of patients at intermediate risk for CAD can be substratified into lower- and higher-risk categories based on the presence or absence of stress-induced ischemia on MPI SPECT and CAC scoring. An integration of SPECT and CAC as a starting point for CAD detection in symptomatic patients at intermediate risk for CAD may facilitate a tailored diagnostic as well as therapeutic approach. Finally, using SPECT/CT, MPI SPECT, and CAC findings may be completed with CT angiography. The development of SPECT/CT hybrid systems is therefore of important value for the nuclear cardiology armamentarium. This editorial commentary outlines a diagnostic pathway of integrated SPECT/CT for CAD assessment in symptomatic patients at intermediate risk for CAD.     

ATP负荷^201Tl心肌断层显像对冠心病的诊断价值

目的评价ATP负荷     

Three-dimensional registration of myocardial perfusion SPECT and CT coronary angiography

OBJECTIVE: In this study, we describe a new technique for three-dimensional registration of CT coronary angiography (CTCA) and gated myocardial perfusion SPECT. METHODS: Twelve patients with known or suspected CAD who underwent CTCA and gated SPECT were enrolled retrospectively. Coronary arteries and their branches were traced using CTCA data manually and reconstructed in three-dimensions. Gated SPECT data were registered and mapped to a left ventricle binary model extracted from CTCA data using manual, rigid and nonrigid registration methods. RESULTS: Three-dimensional reconstruction and volume visualization of both modalities were successfully achieved for all patients. All 3 registration methods gave better quality based on visual inspection, and nonrigid registration gave significantly better results than the other registration methods (p < 0.05). The cost function for three-dimensional registration using nonrigid registration (235.3 +/- 13.9) was significantly better than those of manual and rigid registration (218.5 +/- 15.3 and 223.7 +/- 17.0, respectively). Inter-observer reproducibility error was within acceptable limits for all methods, and there were no significant difference among the methods. CONCLUSION: This technique of image registration may assist the integration of information from gated SPECT and CTCA, and may have clinical application for the diagnosis of ischemic heart disease.     

Underestimation of extent of ischemia by gated SPECT myocardial perfusion imaging in patients with left main coronary artery disease

Background  There have been limited data regarding the value of gated single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) for the detection of left main coronary artery disease (CAD). Methods and Results  We studied 101 patients with angiographic left main CAD (≥50% stenosis) and no prior myocardial infarction or coronary revascularization who underwent gated exercise or adenosine stress technetium 99m sestamibi SPECT MPI. By perfusion assessment alone, high-risk disease with moderate to severe defects (>10% myocardium at stress) was identified in only 56% of patients visually and 59% quantitatively. Absence of significant perfusion defect (≥5% myocardium) was seen in 13% of patients visually and 15% quantitatively. However, by combining visual perfusion data and nonperfusion variables, especially transient ischemic dilation, 83% of patients were identified as high risk. Conclusions  The findings of this study demonstrate that assessment of perfusion data alone by visual or quantitative SPECT MPI analysis underestimates the magnitude of left main CAD. The combination of perfusion and nonperfusion abnormalities on gated MPI identifies high risk in most patients with left main CAD. This study was presented in part at the American College of Cardiology 56th Annual Scientific Session, March 24–27, 2007, New Orleans, La. This work was supported in part by grants from Bristol-Myers Squibb Medical Imaging, Billerica, Mass, and Astellas, Deerfield, Ill.