心肌灌注显像联合冠状动脉钙化积分诊断冠心病的价值及最新进展

心肌灌注显像（MPI）在冠心病的诊断、危险度分层及预后评价中扮演着越来越重要的角色,冠状动脉钙化积分（CACS）可协助对冠心病患者进行进一步的危险度分层,但两者有各自的局限性和不足。将两者联合应用可以相互弥补不足,为临床提供更多的信息。行SPECT/CT心肌灌注显像时,需进行衰减矫正CT（CTAC）扫描,若采用心电门控的呼气末屏气螺旋CT扫描,则在用于MPI衰减矫正的同时又可用于CACS测定,实现一站式检查,在减少患者辐射剂量的同时又可为临床提供更多的信息。笔者综述了CACS、MPI及两者联合应用的临床价值,并对一站式采集MPI与CACS的最新进展进行了综述。     

Dual source computed tomography coronary angiography in new onset cardiomyopathy

AIM:To evaluate safety and utility of coronary computed tomography angiography(CCTA) compared to invasive coronary angiography(ICA) in new cardiomyopathy.METHODS:Eighteen patients(mean age 56.5 years,10 males) who presented for evaluation of new onset heart failure with evidence of systolic dysfunction(ejection fraction < 40%) on echocardiography and recent ICA were prospectively enrolled.Patients with known coronary artery disease,atrial fibrillation,creatinine > 1.5 g/dL,and contraindication to intravenous contrast administration were excluded.CCTA was performed using a dual source 64-slice scanner.Mean heart rate was 75 beats per minute.Stenosis was graded for each coronary segment as:none,mild(< 50%),moderate(50%-70%),severe(> 70%),or non-evaluable.Ischemic cardiomyopathy(ICM) was diagnosed if severe stenosis was present in the left main,proximal left anterior descending artery,or two or more major arteries.RESULTS:Two patients were diagnosed with ICM by ICA.CCTA correctly identified 2 patients with ICM and 16 patients as non-ICM.CCTA successfully evaluated 240/246 coronary segments with an accuracy of 97.5%,sensitivity 70%,specificity 98.7%,positive predictive value of 70%,and negative predictive value of 98.7% for identifying severe stenosis on a per-segment level.CONCLUSION:Dual source 64-slice multi-detector CCTA is a safe,accurate,and non-invasive technique for diagnosing ICM in patients presenting during the acute phase of newly diagnosed cardiomyopathy.     

缺血预适应在急性心肌梗死患者中的临床研究

目的：探讨缺血预适应对急性心肌梗死（acute myocardial infarction,MI）患者梗死面积和左室功能的近期影响。方法：109例行选择性冠状动脉造影和多普勒超声心动图的首次AMI患者,分组比较IP对肌酸激酶同工酶（CK-MB）峰值浓度和左室功能的影响。分为2组：IP组（有梗死前心绞痛）51例;非IP组（无梗死前心绞痛组）58例。结果：CK、CK-MB的峰值浓度IP组显著低于非IP组（P〈0.01）,LVEF值IP组显著高于非IP组（P〈0.05）,二尖瓣口舒张早期血流峰值流速（PE）/舒张晚期血流峰值流速（PA）：IP组显著高于非IP组（P〈0.05）。结论：缺血预适应能够限制AMI患者梗死面积,保护左室功能。     

256层CT评价心肌桥及其与冠状动脉粥样硬化的关系

目的:用256层CT冠脉成像技术评价心肌桥(myocardial bridge,MB)的发生率及其解剖特征与冠状动脉粥样硬化(athorosclerosis,AS)的关系。方法:收集行256层CT冠状动脉成像564例患者的资料,评价MB的有无、部位、长度、厚度、伴发的AS情况及MB解剖特点与AS关系。结果:564例检出MB 131例,159个,总发生率为23.2%(131/564),男性发生率28.8%(90/313)高于女性16.3%(41/251)(χ2=12.048 5,P=0.005)。第一对角支(D1)为最常累及的部位,其次为左前降支(LAD)。完全性MB 83个,不完全性MB 76个;完全性MB长度和厚度中位数分别为27.7mm(范围2.0～71.1mm)和2.4mm(范围1～6.9mm);其长度与厚度间无相关性(R=0.061 1,P=0.106 6)。不完全性MB的长度中位数为24.1mm(范围3.9～57.0mm)。桥血管及桥血管远段血管均未见AS改变。桥血管近段血管AS程度在LAD组高于D1组(χ2=7.576 6,P<0.05),完全性MB组高于不完全性MB组(χ2=7.484 9,P<0.05)。结论:256层CT冠脉成像技术能无创、清晰、可靠地显示活体内MB的存在及解剖特点,并能评估桥血管及其毗邻血管情况。     

甲状腺激素在心血管疾病诊断和治疗中的临床应用

目的 探讨甲状腺激素在心血管疾病诊断和治疗中的临床应用.方法 用发光免疫分析法150例冠心病心力衰竭患者,86例急性心肌梗死(AMI)患者,103例肺心病患者和47名我院健康体检者(正常对照组)血清中的甲状腺激素水平.结果 冠心病心力衰竭患者、AMI患者和肺心病患者血清中三碘甲腺原氨酸(T3)、游离三碘甲腺原氨酸(FT3)及T3/反转三碘甲腺原氨酸(rT3)较正常对照组明显降低(t=2.120、2.214、4.356,P均＜0.05),而血清rT3明显增高(t=2.256、4.416、4.512,P均＜0.05).冠心病心力衰竭患者的血清T3、FT3及T3/rT3随心力衰竭的严重程度明显降低;肺心病急发期较缓解期降低明显,rT3则增加明显.冠心病心力衰竭患者、AMI患者和肺心病患者血清中甲状腺素、游离甲状腺素和促甲状腺激素与正常对照组比较无明显差异(t=1.781、1.813、1.754,P均＞0.05).结论 血清T3、FT3和T3/rT3的降低和rT3的增高是诊断冠心病心力衰竭及严重程度、AMI和肺心病急发期或缓解期的有效指标,并具有治疗后随访的临床价值.     

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。     

导纳法在冠心病心绞痛左心功能检测中的应用

采用导纳法容积描记术对50例冠心病心绞痛患者的左心功能进行检测,并与40例健康者进行对照研究。结果表明,前者左心功能明显减退(P<0.01),且其左心功能受损程度随缺血部位和范围加大而加重。因此,导纳法容积描记术可作为冠心病左心功能测试与评价的手段之一。     

冠状动脉造影表现与临床特征对照分析（附220例报告）

目的：对220例CAG影像表现与临床特征进行对照分析探讨两者之间的关系。方法：回顾性分析220例CAG的影像表现及临床特征。结果：CAG显示冠状动脉正常115例、狭窄105例,（男89例,女16例）,其中单支狭窄45例（42．9％）、2－3（左主干）支60例（57．1％）,轻度狭窄4例（3．8％）、中度狭窄14例（13．3％）、重度狭窄87例（82．9％）。结论：通过CAG可以明确诊断冠心病及全面了解冠状动脉狭窄的程度,也提示了冠心病患者一旦出现临床症状,冠状动脉狭窄一般较为严重。     

梗塞前心绞痛对急诊冠脉再通病人心梗范围的限制作用

目的 :了解急性心肌梗塞前 2 4h内的心绞痛对急性心梗再灌注成功患者的心肌是否有保护作用。方法 :经静脉溶栓或 /和PTCA治疗成功的急性心梗患者 5 0例 ,根据心梗前 2 4h有无心前区疼痛分为A和B二组 ,比较两组CK峰值、QRS计分、CK峰值指数 (CK峰值 /QRS计分 ) ,分析影响心梗面积的因素。结果 :QRS计分与CK峰值呈直线相关关系 ,而与入院时间、年龄等因素无关 ;虽然冠脉的病变程度、CK峰值两组无显著差异 ,但CK峰值指数A组为 5 5 4.2± 40 1.2 ,B组为 75 0 .5± 6 0 3.3;胸痛组有降低趋势 (P =0 .15 8)。结论 :提示梗塞前心绞痛可能对心梗再灌注成功患者的心肌有一定保护作用。     

冠状动脉钙化CT检出率及其意义的探讨

我们使用ＥＬＳＣＩＮＴ２４００型全身ＣＴ扫描机，连续对２０５例胸部进行平扫检查，发现冠脉钙化４４例，占２１．５％。５０例４０岁以下者未发现冠脉钙化；１５５例４０岁以上者，冠脉钙化检出率随着年龄增加而增加，其中５８例诊断冠心病，４０例有冠脉钙化；９７例无冠心病者，４例有冠脉钙化。着重探讨冠脉钙化与冠心病的关系，其灵敏度、特异度及阳性予告值分别为６９％、９６％及９１％。ＣＴ检出冠脉钙化虽不很敏感，但却能说明发生冠心病的机率较高，因而仍应将它视为一种重要的非损伤性检查方法。     

Unusual origin and course of the first septal branch of the left coronary artery: Angiographic recognition

The anatomical variants of the origin and course of the first septal branch (S1) of the left coronary artery system have received little attention in the literature dealing with coronary angiography. We describe here the angiographic features of the ectopic origin of S1 from epicardial branches of the left coronary artery other than the left anterior descending artery as observed in 8 cases from a series of 700 consecutive patients (1.1%). The S1 originated from the left main coronary artery in 1 case, from a diagonal branch in 4, and from an intermediate branch in 3 cases. Previous reported cases are reviewed. Because the S1 may supply up to 15% of the blood to the myocardium, the recognition of this variable origin may have clinical implications and has to be considered as a part of the complete evaluation of coronary arteriograms of patients referred for coronary artery revascularization.     

Functional alterations in the coronary circulation as mirrored in the angiogram

The ability of coronary arteriography to disclose the presence of abnormalities in the coronary arteries is undisputed. On the other hand, it is less clear whether the angiographic examination of the coronary circulation permits an assessment of functional abnormalities, which may involve the coronary circulation in toto or regionally. The most commonly practiced grading of angiographically demonstrated coronary artery disease is based on the degree of arterial narrowing and the number of major vessels that are involved. This approach, however, suffers from significant shortcomings, which are mainly related to the limitations in accuracy of measuring such lesions angiographically. Secondary angiographic signs of impaired coronary flow, such as contrast propagations through collateral channels, delayed, stagnant, and reciprocal flow pattern, and the appearance of excessive peripheral myocardial contrast accumulation may gain great importance. In conjunction with the presentation of a number of cases considered to be representative for different situations of chronic and acute myocardial ischemia, the primary and secondary angiographic findings are accounted for in detail and discussed as to the most likely existing pathophysiology. The discussion also includes knowledge based on experiments performed in in vitro or animal models and tries to establish a synthesis between the different angiographic phenomena and the present status of our understanding of the pathophysiology of myocardial injury. It is concluded that such detailed analysis of the angiographic events may yield important information for the most appropriate management of the individual patient.     

青年和老年急性心肌梗死临床及冠状动脉病变特点的差异研究

目的：比较青年和老年急性心肌梗死（AMI）患者临床及冠状动脉病变特点。方法：入选我院10年的≤40岁AMI患者83例,≥60岁AMI患者463例,比较两组患者病史、临床特点及冠状动脉病变特点。结果：与老年组比较,青年AMI患者男性更多见,具有吸烟史、饮酒史的患者比例更高,更多患者具有冠心病家族史,TC、LDL-C水平明显高于老年患者,而高血压病史、糖尿病史、既往心绞痛发作史患者比例均低于老年患者（P〈0.05）;青年AMI组造影正常或单支病变比例明显高于老年AMI组,而双支/多支病变比例低于老年组,差异具有统计学意义（P〈0.05）;老年AMI患者累及RCA和LCX的比例明显高于青年组,差异具有统计学意义（P〈0.05）。结论：吸烟、饮酒、代谢紊乱和家族史是≤40岁AMI的主要危险因素;青年AMI患者冠脉病变程度显著低于老年组患者。     

核心脏病学在心力衰竭中的临床应用

核心脏病学的显像技术是一种常用的无创的诊断心力衰竭的重要手段,在评估心力衰竭程度和指导心力衰竭治疗方面发挥了重要作用。定量门控SPECT心肌灌注显像借助其定量分析软件,可以定量评价心脏容积、左心室射血分数、每搏输出量、心脏舒张功能。静息和（或）负荷心肌灌注显像不仅能鉴别非缺血性心力衰竭和缺血性心力衰竭,而且能判别心肌是否存在活性。核心脏病显像技术能轻易地鉴别出舒张性心力衰竭（也称为射血分数正常的心力衰竭）,它通过高峰充盈率和高峰充盈率时间可以准确地评估舒张性心力衰竭的程度。借助三维成像等新技术定量门控SPECT能有效评估左室运动情况,评估室壁厚度对其是一个很好的补充。心肌灌注显像还常用于判别患者是否适合植入心脏除颤器及是否适合进行心脏再同步化治疗。123I-间碘苄胍神经递质显像能为心力衰竭患者提供预后信息。心肌代谢活动与其功能密切相关,能量代谢底物是评价药物治疗是否有助于提高心力衰竭患者心功能的一个指标,123I-15-(p-碘苯基)3-R,S-甲基十五烷酸是一种临床研究中常用的心肌代谢显像示踪剂。借助新示踪剂的应用,包括神经递质显像和心肌代谢显像在内的核心脏病学显像技术常用来完善心力衰竭的诊断。核心脏病学显像技术在诊断心力衰竭及指导临床治疗方面做出了巨大贡献。     

Determinants and impact of microvascular obstruction in successfully reperfused ST-segment elevation myocardial infarction. Assessment by magnetic resonance imaging

Microvascular obstruction (MVO) is an important and independent determinant of post-infarct remodeling. Fifty-two patients with a successfully reperfused ST-segment elevation acute myocardial infarction (MI) were studied with MRI in the first week and at 4 months post-infarction. On early (i.e., 2–5 min) post-contrast MRI, MVO was detected in 32 patients with an MVO to infarct ratio of 36.3 ± 24.9%. On late (i.e., 10–25 min) post-contrast MRI, MVO was detected in only 27 patients, with an MVO to infarct ratio of 15.9 ± 13.9%. MVO infarcts (n = 32) were associated with higher cardiac enzymes (troponin I, P = 0.016), and lower pre-revascularization thrombolysis in myocardial infarction (TIMI) flow (P = 0.018) than non-MVO infarcts (n = 20). Infarct size was larger in MVO infarcts (25.0 ± 14.3 g) than non-MVO infarcts (12.5 ± 7.9 g), P = 0.0007. Systolic wall thickening in the infarct and peri-infarct area, and left ventricular (LV) ejection fraction (EF) were worse in MVO (46.1 ± 7.2%) than non-MVO infarcts (50.5 ± 6.6%, P = 0.038). At 4 months, MVO infarcts showed more adverse remodeling and lack of functional improvement, whereas non-MVO infarcts improved significantly (LV EF at 4 months, MVO, 47.5 ± 7.8%, P = 0.31; non-MVO, 55.2 ± 10.3%, P = 0.0028). In the majority of patients with successfully reperfused ST-segment elevation MI, MVO is observed, whose present and maximal extent can be best evaluated on early post-contrast MRI. Presence of MVO is associated with more extensive infarctions, and characterized by greater adverse LV remodeling and lack of functional recovery.     

冠状动脉造影和颈动脉超声对动脉粥样硬化的比较研究

目的：了解颈动脉粥样硬化和冠状动脉粥样之间的关系,为寻求简单、无创伤和常规检查动脉粥样硬化程度,评估冠心病发病可能。方法：选择一组年龄62～89岁老年研究样本,分别进行冠状动脉造影和颈动脉彩超,分别记录冠状动脉狭窄程度、狭窄支数,彩超记录动脉壁厚、内膜厚、内径狭窄程度、硬化斑块数、收缩期和舒张期血流峰值速度等参数,比较冠状动脉和颈动脉硬化参数间关系。结果：颈动脉动脉粥样硬化出现病变程度随着冠状动脉病变血管支数和斑块数增加而增加。另外,这些变化还出现在内膜厚度／腔内径比值,收缩期峰值血流,舒张期峰值血流等血流变等方面,两者病变呈一定程度相关性。结论：冠状动脉粥样硬化与颈动脉粥样硬化具有高度的相关性,颈动脉超声粥样斑块的检测作为一无创、简单易行手段可作为预测冠心病发病的重要预测信号。     

Value of conventional chest radiography for the detection of coronary calcifications: comparison with MSCT

Purpose

To evaluate if computed tomography (CT) coronary calcium scoring is needed after detection of coronary calcifications on conventional chest radiographs.

Materials and methods

One hundred and five patients (67 men; 57.2 ± 12.8 years) with suspected coronary artery disease underwent conventional chest radiography and non-enhanced, retrospectively ECG-gated multislice spiral CT (MSCT) of the heart (4 mm × 2.5 mm, 120 kV, 133 mAs_eff.). Chest radiographs were assessed independently by two radiologists. Detection of coronary calcifications was compared between both methods. Sensitivity, specificity, negative and positive predictive values, median, 25% and 75% percentiles for the detection of coronary calcifications were calculated. Receiver operating characteristics (ROC) analyses were computed.

Results

In 90 patients, MSCT revealed coronary calcifications. The mean coronary calcium score was 526.2 (0–4784.5). On chest radiographs, coronary calcifications were correctly detected in 46 (61) patients by observer 1 (observer 2). The corresponding sensitivity was 51.1% in observer 1 and 67.8% in observer 2. Median of detected coronary calcifications was 361.9 (426.4) for observer 1 (observer 2). Corresponding 25% und 75% percentiles were 109.6 (109.6) and 798.5 (898.5). The area under the ROC curve was 0.636 for observer 1 and 0.715 for observer 2. There was no correlation between image quality and the detection of coronary calcifications on plain film radiographs.

Conclusion

As coronary calcifications of various extents are inconsistently detected on plain chest radiographs, CT calcium scoring may not be omitted even if coronary artery calcifications were detected on conventional chest radiographs.     

心肌灌注显像与冠状动脉钙化积分对冠心病风险评估的研究现状及相互关系

冠心病是严重威胁人类健康的常见病和多发病.早期诊断冠心病,无创、准确地进行心脏不良事件的风险评估并及时干预,是亟待解决的临床问题.风险评估模型对于心脏风险评估的有效性虽已被众多临床试验所证实,但仍有局限性.心肌灌注显像及冠状动脉钙化积分以及两者结合,为冠心病诊断及心脏风险的评估提供了新的思路.     

Selective use of coronary calcification measurements in an expanded intermediate risk group

Risk assessment is an imperative initial step in the clinical management of cardiovascular risk factors. On the basis of the estimation of the 10-year absolute risk of manifesting coronary heart disease (myocardial infarction or coronary heart disease death), risk categories are conventionally divided into low, intermediate, and high. The most widely used quantitative risk assessment algorithm, the Framingham risk score for hard events, is based on traditional risk factors, but it does not fully account for all available cardiovascular risk factors. Current national guidelines defining coronary heart disease risk categories based on the Framingham risk score may inaccurately assign persons with a high burden of subclinical coronary atherosclerosis to a low-risk group (<10% risk), failing to predict the true risk of a cardiovascular event. Coronary artery calcification as a measure of subclinical atherosclerosis has already established itself as a useful adjunct for refining the broad intermediate risk category of adults, leading to more decisive management strategies. In a point-counterpoint format this article argues for the improved accuracy of coronary calcium scoring in predicting the risk of future cardiac events in persons with a low Framingham risk score (including women and different ethnic groups). To better incorporate recent scientific findings into cardiovascular assessment and to refine stratification in those with a low Framingham risk score, we therefore propose a timely algorithm supporting coronary calcium screening in a selected group of low-risk persons.     

降低冠状动脉钙化伪影的CT技术进展

传统冠状动脉CT血管成像（CCTA）可因冠状动脉钙化而降低诊断效能,致使管腔狭窄程度被高估,进而增加不必要的有创性血管造影检查。随着CT空间分辨力提高、新的去伪影算法、双能CT成像技术、冠状动脉减影技术、迭代重建技术及锐利卷积核重建技术的出现与发展,冠状动脉钙化在心脏CT影像上的伪影得以减轻,CT对冠状动脉钙化病人的诊断效能明显提高。就多种降低冠状动脉钙化伪影的CCTA成像技术进展进行综述。