~(99)Tc~m-MIBI门控心肌显像测定局部室壁收缩增厚率对冠心病的诊断价值

目的　探讨心肌局部室壁收缩增厚率 (STR)与心肌局部室壁运动状态和冠状动脉 (简称冠脉 )狭窄程度间的关系及其临床意义。方法　对 34例冠心病 (CAD)患者和 8例正常受检者行静息99Tcm 甲氧基异丁基异腈 (MIBI)门控心肌断层显像。根据冠脉和左室造影所得冠脉狭窄程度和运动状态分组。取收缩末期和舒张末期图像计算STR值。结果　对照组和CAD无室壁运动异常组与室壁运动减弱组、无室壁运动组及矛盾运动组之间的STR值差异均有显著性 (P <0 .0 1或P <0 .0 5 ) ;对照组与冠脉轻度、中度、重度狭窄节段之间STR差异均有显著性 (P <0 .0 1或P <0 .0 5 ) ,且STR与该节段供血冠脉狭窄程度呈负相关 (r =- 0 .74,P <0 .0 1)。STR判定室壁运动异常的灵敏度为77 9% ,特异性为 90 .9% ;判断冠脉中度以上狭窄 (冠脉狭窄 >5 0 % )和重度狭窄 (冠脉狭窄 >80 % )的灵敏度分别为 5 3.8%和 73.4% ,特异性分别为 93.1%和 88.9%。结论　STR可比较准确地反映心肌局部室壁运动状态及局部供血冠脉的狭窄程度     

Lung clearance of inhaled aerosol of Tc‐99m‐methoxyisobutyl isonitrile: relationships with cigarette smoking,age and gender

Tc‐99m‐methoxyisobutyl isonitrile (Tc‐99m‐MIBI) is a radiolabelled xenobiotic, the disappearance rate of which from lungs following inhalation as a radioaerosol correlates inversely with bronchopulmonary multidrug resistance protein 1 (MRP1) expression. Tc‐99m‐MIBI clearance has previously been shown to be delayed in cigarette smokers. The aim of the current study was to determine whether smoking correlates with bronchopulmonary MRP1 expression, to confirm that Tc‐99m‐MIBI disappearance rate from the lungs following inhalation is delayed in smokers, and to determine the effects of gender and age on disappearance rate. Participants underwent dynamic imaging for 40 min over the lungs following inhalation of Tc‐99m‐MIBI using a double‐headed gamma camera. The half‐time of clearance was obtained from geometric mean of anterior and posterior counts and averaged between the two lungs. Paraffin‐embedded tissue obtained from healthy lung during surgery in 13 patients was graded immunohistochemically for MRP1 as negative (0), weak (1), moderate (2) or strong (3). In 4 non‐smokers, grading was 1 in three and 0 in one. In 9 smokers, in contrast, expression was graded 2–3 in 8 and 1 in one (P<0·02). Mean clearance half‐time in smokers (142 ± 29 min; n = 17) was longer than in non‐smokers (91 ± 14 min; n = 18; P<0·0001). In non‐smokers, half‐times were not significantly different between men (96 ± 16; n = 6) min and women (88 ± 12 min; P = 0·2). Combining genders into one group, half‐time correlated with participant age (P = 0·0005). We conclude that smoking upregulates MRP1 and delays clearance of inhaled Tc‐99m‐MIBI. There is no significant gender difference in non‐smokers but ageing is associated with longer clearance half‐times.     

A comparative evaluation of Tl-201 and Tc-99m sestamibi myocardial perfusion spect imaging in diabetic patients

Aim Myocardial perfusion scintigraphy (MPS) is an effective tool for early diagnosis of coronary artery disease (CAD) in type II diabetes mellitus (DM). The purpose of this study was to review the comparative findings of Tc-99m MIBI and Tl-201 MPS in defining normal and abnormal myocardial segments, type and extent of the perfusion defects with reference to coronary angiography findings in diabetic patients. Methods Thirty patients with type II DM who had abnormal Tc-99m MIBI MPS findings and underwent coronary angiography were included this study (20 male, 10 female; mean age was 64 ± 11 years). Those patients were also investigated with Tl-201 MPS thereafter. All scintigraphic images were evaluated semiquantitatively using a 20-segments myocardial model. The perfusion of myocardial segments, reversibility and severity of defects based on defect score were compared using the MIBI and Tl-201 images in relation to coronary angiography. Diffuse slow-washout of Tl-201 was also noted. Results A total of 600 myocardial segments were comparatively analyzed. Diagnostic concordance between both tracers in defining normal and abnormal perfusion on a segmental basis was 88% (κ = 0.71). The percentage of normal, reversible and non-reversible segments in the Tc-99m MIBI and Tl-201 study were 67–61%, 11–20% and 22–19% respectively. While the number of irreversible defects were similar for both tracers, more number of reversible defects were identified by Tl-201 MPS than Tc-99m MIBI (65 vs. 123, p = 0.001). No significant difference between the defect scores of both tracers was found. Conclusion MPS using both tracers offered agreement in defining or excluding perfusion abnormalities in a major part of the data. However, Tl-201 MPS yielded better detection rate of myocardial ischemia than Tc-99m MIBI MPS in diabetic patients.     

腺苷负荷心肌灌注显像对近期经皮冠状动脉介入治疗患者的临床价值

目的评估腺苷负荷心肌灌注显像（SMPI）在冠心病患者接受经皮冠状动脉介入治疗（PCI）后的临床价值。方法20例冠心病患者PCI前及后3d内各行1次腺苷SMPI。静息心肌灌注显像（RMPI）于PCI前SMPI的次日进行。心肌显像按17节段5分制进行评分。PCI后1年对患者进行电话随访（随访者不知晓患者的检查结果），在此期间发生心肌梗死或心因性死亡为严重心脏事件（HCE），PCI3个月后再次接受PCI或搭桥手术为非严重心脏事件（SCE）。率的比较行χ^2检验，频数比较行秩和检验。结果PCI前血管供血区域的可逆性节段，PCI后示90．9％（40／44）灌注有改善，不可逆缺损节段亦有41．3％（25／58）显示不同程度的改善。PCI后1年内出现1例HCE，5例SCE，预后与PCI前后受损节段灌注改善情况无关（χ^2=3．17，P〉0．05）。结论PCI后近期腺苷SMPI是评估PCI后心肌灌注的有效方法，其中可逆性缺损改善与否是评估PCI疗效的可靠指征；其预后价值有待进一步研究。     

用门控心肌显像评价重组腺病毒-肝细胞生长因子治疗缺血性心脏病

目的 探讨99Tcm-甲氧基异丁基异腈(MIBI)静息门控心肌灌注显像(G-MPI)评价重组腺病毒-肝细胞生长因子(Ad-HGF)心肌内直接注射对缺血性心脏病早期治疗的价值.方法 18例冠心病患者根据随机分组表分为小、中、大剂量Ad-HGF治疗组,分别接受5×108,1.5×109,5×109空斑形成单位(PFU)/点(均分10点注射)的Ad-HGF心肌内直接注射.所有患者于治疗前后分别行静息G-MPI,以评价心功能和注射部位心肌血流灌注的变化.采用Stata 7.0软件进行统计学处理.结果 (1)与治疗前相比,小剂量组中有3例、中剂量组中有5例、大剂量组中有6例患者于Ad-HGF注射区域出现心肌血流灌注的改善,改善情况与注射剂量有量-效关系(X2=4.34, P＜0.05).(2)18例患者治疗前静息左心室射血分数(LVEF)、左心室舒张末期容积(EDV)和收缩末期容积(ESV)分别为(50.1±6.4)%,(137.7±33.2)和(70.2±22.4)ml;治疗后分别为(58.7±5.6)%,(123.7±32.7)和(51.9±14.9)ml.LVEF治疗后较治疗前有增加(t=6.1, P＜0.01),EDV和ESV则明显降低(t值分别为5.9,6.4,P均＜0.01).(3)低、中、高剂量Ad-HGF治疗组治疗前LVEF为(50.3±4.9)%,(52.0±5.4)%和(47.8±8.8)%,治疗后LVEF为(54.7±4.1)%,(58.8±3.9)%和(62.5±6.3)%.治疗前后LVEF的差值分别为(4.3±1.2)%,(6.8±5.7)%和(8.6±5.9)%,各组治疗后LVEF均增加:其中高剂量组的增加幅度明显高于中、低剂量组(t=3.3, P＜0.05; t=4.3, P＜0.01),中、低剂量组之间差异无统计学意义(t=1.1, P＞0.05).治疗前后LVEF的变化幅度与注射Ad-HGF剂量有量-效关系(Spearman相关系数为0.67, P＜0.01).结论 G-MPI可用于评价Ad-HGF心肌内直接注射治疗缺血性心脏病早期疗效.     

Clinical usefulness of ECG-gated18F-FDG PET combined with99mTc-MIBI gated SPECT for evaluating myocardial viability and function

OBJECTIVES: This study sought to evaluate an imaging approach using gated 99mTc-MIBI (MIBI) SPECT and gated 18F-FDG (FDG) PET for assessment of myocardial viability and cardiac function. METHODS: Forty-eight patients (38 men, mean age 68.1 +/- 9.6 years) underwent ECG-gated FDG PET and MIBI SPECT within a week. The baseline diagnoses were coronary artery disease (31), mitral regurgitation (1), paroxysmal arrhythmia (10), and dilated cardiomyopathy (6). The gated FDG PET data were analyzed using pFAST software, and the gated MIBI SPECT data were analyzed using QGS software. Fifteen patients were diagnosed with myocardial infarction, and follow-up study was performed to assess the functional outcome four months later. An improvement in LVEF of >5% was defined as significant. The LV myocardium was divided into 17 segments, and regional defect scores were visually assessed using a 4-point scale for each segment (0 = normal, 1 = mildly reduced, 2 = moderately reduced, 3 = absent). A segment with a greater defect score on MIBI SPECT than on FDG PET was defined as a mismatch. The patients were divided into two groups: those with at least two mismatched segments (MM-group), and those with none or one (M-group). RESULTS: LVEF, EDV and ESV measured by gated FDG PET were highly correlated with those obtained by gated MIBI SPECT (r = 0.848, 0.855 and 0.911, p < 0.0001, respectively). The mean values of LVEF did not differ significantly, but EDV and ESV obtained by gated FDG PET were significantly grater than those obtained by gated MIBI SPECT (p < 0.0001). In 15 patients diagnosed with myocardial infarction, a significant association (p < 0.05) was found between the relative uptake of FDG PET and MIBI SPECT and the functional outcome 4 months later. Global LV function improved in 6 of the 8 patients showing mismatch but in only 1 of the 7 patients with matched defects, resulting in a sensitivity of 86% and specificity of 75%. The overall accuracy to predict global functional outcome was high (80%). CONCLUSION: This imaging approach allows accurate evaluation of myocardial viability. Furthermore, the high correlations of gated FDG PET and gated MIBI SPECT measurements hold promise for the assessment of left ventricular function using gated FDG PET.     

乳腺癌99Tcm-MIBI显像与P-糖蛋白表达的临床研究

目的 研究乳腺癌患者^99Tc^m-甲氧基异丁基异腈（MIBI）显像与癌组织中P-糖蛋白（P-gP）表达的关系。方法对98例未经治疗的乳腺癌患者进行^99Tc^m-MIBI早期（10min）与晚期（120min）平面显像，用免疫组化方法检测术后标本中P-gP的表达，根据免疫组化的结果将患者分为2组，对84例^99Tc^m-MIBI显像阳性的患者分别比较肿瘤的早期和晚期与健侧放射性计数比值（T／N）以及肿瘤部位的放射性清除率（Washout rate，WOR）。结果53例P-gp表达阳性患者的早期T／N值明显高于31例P-gP表达阴性患者（P〈0．001），差异有显著性；两组间的WOR差异也有显著性（P〈0．001）。5例P-gP表达阳性和9例P-gP表达阴性患者^99Tc^m-MIBI显像阴性。结论^99Tc^m-MIBI乳腺显像与WOR的测定有助于预测未经治疗的乳腺癌患者的P-gP表达情况，但对乳腺显像阴性的患者难以判定。     

Clinical validation of technetium-99m MIBI-gated single-photon emission computed tomography (SPECT) for avoiding false positive results in patients with left bundle-branch block: comparison with stress-rest nongated SPECT

BACKGROUND: Septal perfusion defects are common on myocardial perfusion single-photon emission computed tomography (SPECT) slices in patients with left bundle-branch block (LBBB) in the absence of coronary artery disease. HYPOTHESIS: The use of gated myocardial perfusion SPECT imaging in such patients should be clinically validated. The aims of this study were, therefore, to validate clinically the use of gated myocardial SPECT imaging to avoid false positive septal perfusion defects in patients with LBBB and to compare nongated and gated SPECT imaging techniques in the same patients in the same imaging session. METHODS: We performed stress-rest myocardial perfusion SPECT and resting gated SPECT using Technetium-99m MIBI in 25 patients with LBBB and in 6 control subjects. Stress-rest SPECT images and end-diastolic and end-systolic gated SPECT slices were assessed visually and quantitatively (septum/lateral wall count ratio). Coronary angiography was performed in 15 patients with LBBB and in all 6 control subjects. RESULTS: Stress-rest (nongated) SPECT slices and end-diastolic and end-systolic gated SPECT images were normal in all control subjects. Stress-rest (nongated) SPECT imaging revealed septal perfusion defect in 20 (11 reversible, 9 irreversible) patients with LBBB, whereas the figures were 15 and 5 for end-systolic and end-diastolic gated SPECT images, respectively. Coronary angiography results were normal in all control subjects and in 15 patients with LBBB. Quantitative analysis of gated SPECT images revealed no statistically significant difference between patients with LBBB and control subjects in end-diastolic mean septum/lateral wall count values (0.86 +/- 0.19 in LBBB vs. 0.98 +/- 0.15 in normal subjects, p > 0.05), but the difference was statistically significant for end-systolic, stress, and rest values (p < 0.001 for all). CONCLUSION: Gated SPECT imaging, particularly end-diastolic images, revealed fewer false positive results and thus can be used to avoid false positive septal perfusion defects commonly seen in stress-rest (nongated) myocardial perfusion SPECT in patients with LBBB.     

甲亢患者的心肌灌注断层显像改变

目的:了解毒性弥漫性甲状腺肿(Graves病,GD)患者心肌灌注显像改变的临床意义。方法:应用SPECT仪对24例GD患者及20例正常对照者进行~(99m)Tc-MIBI心肌灌注显像。将左心室分成9个节段进行分析。分别计算2组受检者的放射性分布异常节段数及异常节段百分率,并进行比较。结果:24例GD患者中18例有放射性发布异常节段共60个,占总节段数的27.8％,经x~2检验,与对照组相比有显著性差异(P<0.01)。放射性分布异常节段以心尖部、前壁、前基底、下壁及后壁为多见,其中放射性分布明显稀疏共9个节段,占总节段数的4.2％。结论:心肌灌注显像可发现无心脏病临床表现的GD患者心肌缺血的部位、大小及严重程度,该方法简便、安全、可靠、无创伤。     

潘生丁负荷99mTc-MIBI心肌断层显像对冠心病心肌缺血的诊断价值

目的评价潘生丁负荷99mTc-MIBI心肌断层显像用于冠心病心肌缺血诊断的可行性和临床价值.方法静脉注入潘生丁0.14 mg·kg-1·min-1,共4 min,1 min后注射99mTc-MIBI 740 MBq,1 h后行心肌断层显像.结果潘生丁负荷心肌断层显像诊断冠心病心肌缺血的灵敏度为92.5%,特异性为92.1%.潘生丁注入后引起的副作用轻微且较短暂.结论潘生丁负荷99mTc-MIBI心肌断层显像用于诊断冠心病心肌缺血有较高的准确性.