定量门控201Tl心肌显像对冠心病患者的预后价值

目的 研究定量门控201Tl心肌显像对冠心病患者预后评估及冠心病治疗方案选择的价值.方法 对84例患者进行静息和运动负荷201Tl门控心肌灌注SPECT显像,并随访(32.92±16.77)个月.对心肌灌注图像进行评分(1～4分),计算总负荷评分(SSS)、总静息评分(SRS)和总差值分(SDS=SRS-SSS)、负荷左室射血分数(EF)值和静息EF值.结果 随访中9例发生心脏事件,年发生率为3.90%.SSS、SDS、SRS以及EF值均是心脏事件的独立预测因素(P＜0.005).Cox比例风险回归分析示SSS是心脏事件的最强预测因素.根据患者的负荷后EF值、SDS等可将患者分为低危、中危和高危组.结论 应用定量门控201Tl心肌显像可以对冠心病患者进行正确的预后评估,并可指导选择治疗方案.SSS是心脏事件的最强预测因素.     

Cost-effectiveness of exercise 201Tl myocardial SPECT in patients with chest pain assessed by decision-tree analysis]

To evaluate the potential cost-effectiveness of exercise 201Tl myocardial SPECT in outpatients with angina-like chest pain, we developed a decision-tree model which comprises three 1000-patient groups, i.e., a coronary arteriography (CAG) group, a follow-up group, and a SPECT group, and total cost and cardiac events, including cardiac deaths, were calculated. Variables used for the decision-tree analysis were obtained from references and the data available at our hospital. The sensitivity and specificity of 201Tl SPECT for diagnosing angina pectoris, and its prevalence were assumed to be 95%, 85%, and 33%, respectively. The mean costs were 84.9 x 10(4) yen/patient in the CAG group, 30.2 x 10(4) yen/patient in the follow-up group, and 71.0 x 10(4) yen/patient in the SPECT group. The numbers of cardiac events and cardiac deaths were 56 and 15, respectively in the CAG group, 264 and 81 in the follow-up group, and 65 and 17 in the SPECT group. SPECT increases cardiac events and cardiac deaths by 0.9% and 0.2%, but it reduces the number of CAG studies by 50.3%, and saves 13.8 x 10(4) yen/patient, as compared to the CAG group. In conclusion, the exercise 201Tl myocardial SPECT strategy for patients with chest pain has the potential to reduce health care costs in Japan.     

Thallium-201 washout in coronary artery disease using SPECT — a comparison with coronary angiography

In this study, tomographic ²⁰¹Tl washout analysis and coronary angiography were compared in 100 subjects. Seventeen subjects with healthy coronary arteries were used as reference material, on the basis of which the reference ranges for both the total washout of the heart muscle and the regional washout were determined. With angiography as the standard, this material yielded the following sensitivity values for total myocardial washout: 80% for three vessel proximal disease (n=30), 64% for peripheral three vessel disease (n=14), 66% for two vessel disease (n=29) and 71% for single vessel disease (n=17). Specificity in the reference group was 94%. Sensitivity values for regional washout were 83%, 93%, 59% and 71%, respectively. Stress ECG gave about 10% lower sensitivities. As far as sensitivity is concerned, however, visual assesment of tomographic images proved to be the best single method. In three patients, washout analysis was necessary to reveal evenly distributed ischemia and in seven cases it was essential in order to confirm an uncertain diagnosis; in other words, washout analysis had diagnostic value in 10 of the 100 patients.     

运动201Tl肺/心比值对高血压合并冠状动脉疾病的临床价值

目的评价运动201Tl肺/心比值对高血压合并冠状动脉疾病(CAD)患者冠状动脉病变严重程度的诊断价值及其与左室舒张功能的相关性.方法 19例正常对照者.102例经冠状动脉造影确诊的CAD患者,分为3组无高血压、高血压无心肌肥厚和高血压心肌肥厚组.受检者均行运动-延迟心肌灌注断层显像,取运动断层显像上的前位显像计算肺/心比值.结果无高血压组(0.43±0.09,t=3.01)、高血压无心肌肥厚组(0.42±0.12,t=2.10)和高血压心肌肥厚组(0.47±0.09,t=4.76)的肺/心比值均较对照组(0.36±0.05,P<0.05～0.01)显著为高,但3组间相比差异均无显著性(P均>0.05);上述3组单支和多支病变的肺/心比值分别为0.40±0.09和0.46±0.10、0.38±0.11和0.48±0.12及0.46±0.11和0.48±0.10.前2组单支与多支相比差异均有显著性(P均<0.05),后组差异无显著性(P>0.05);3组患者肺/心比值≥0.45时对多支病变的诊断灵敏度和特异性分别为82%和75%、90%和75%及40%和45%.无高血压组(r=0.402,P<0.01)和高血压无心肌肥厚组(r=0.408,P<0.05)的肺/心比值与半定量评分均呈显著正相关,但高血压心肌肥厚组(r=0.114,P>0.05)与半定量评分无相关性.无高血压组(r=-0.413,P<0.01)、高血压心肌肥厚组(r=-0.662,P<0.01)和高血压无心肌肥厚组的肺/心比值(r=-0.408,P<0.05)与早期(E)和晚期(A)充盈速率比值均呈显著负相关.结论运动肺/心比值对伴和不伴高血压CAD患者的冠状动脉多支病变及左室舒张功能异常均有较好的诊断价值,但对高血压心肌肥厚CAD患者多支病变的诊断价值不大.     

Ability of 201Tl and 123I-BMIPP mismatch to diagnose myocardial ischemia in patients with suspected coronary artery disease

Objective  

A mismatch defect between ²⁰¹TL and ¹²³I-BMIPP dual isotope SPECT (d-SPECT) is useful to detect myocardial ischemia in patients with acute coronary syndrome. However, whether mismatched d-SPECT findings reflect actual myocardial ischemia in stable patients with suspected, but unknown ischemic heart disease is unclear. The present study assesses the significance of a d-SPECT mismatch among such patients.     

ATP负荷~(201)Tl心肌断层显像对冠心病的诊断价值

目的　评价ATP负荷2 0 1Tl心肌断层显像用于冠心病患者诊断的可行性和临床价值。方法　静脉注入ATP 0 .14mg·kg-1·min-1共 3min ,之后注射2 0 1Tl 148MBq ,10min和 3～ 4h后分别作心肌断层显像。结果　ATP负荷2 0 1Tl心肌断层显像诊断冠心病的灵敏度为 88% ,特异性为 90 %。ATP注入后引起的副作用轻微而短暂。结论　ATP负荷2 0 1Tl心肌断层显像用于诊断冠心病有较高的准确性     

Thallium-201 SPECT in coronary artery disease patients with left bundle branch block

Fourteen patients with left bundle branch block (LBBB) underwent immediate postexercise and 3-hr delayed 201Tl single photon emission computed tomography (SPECT) with quantitative analysis using bullseye polar maps. Test performance in detecting individual coronary artery stenosis greater than or equal to 50% demonstrated 100% sensitivity. Specificity was 100% for circumflex stenosis, 78% for right coronary stenosis, but only 10% for left anterior descending coronary stenosis. This very low specificity was due to the fact that 3/4 (75%) patients with left anterior descending stenosis and also 9/10 (90%) patients with normal left anterior descending coronary arteries had immediate septal perfusion defects with redistribution in all cases at 3 hr. Septal abnormalities were most marked in patients who achieved high peak heart rates (greater than 170 bpm). Thus, with LBBB, 201Tl SPECT is indeterminate for left anterior descending coronary disease.     

Abnormal thallium-201 chloride myocardial SPECT findings with noncritical coronary angiography in a patient after coronary artery bypass graft

Conclusion  We report on a patient with a previous CABG and symptoms similar to syndrome X who had normal angiography and significant abnormal ²⁰¹Tl perfusion. The discrepancy of the two imaging modalities could have occurred because, fundamentally, SPECT is a physiologic measurement that reflects perfusion of the myocardium, while coronary angiography reflects only anatomy, and it is known that anatomy may not predict perfusion well. Coronary angiography may underestimate the severity of coronary disease, atheromatosis involving coronary vascular wall, and its related perfusion. Another possibility is that coronary blood supply was diverted/stolen by 1 proximal branch of the left internal mammary artery during the exercise. Lastly, during stress there was an inability to increase flow reserve, resulting in decreased perfusion pressure to the collateral supply of the septal perforators from the saphenous venous graft to the distal right coronary artery. Stress and delayed ²⁰¹Tl SPECT imaging provide insight into regional flow, cellular integrity, and viability, providing a valuable technique of assessing the presence of resting and provokable ischemia.     

Comparison of 99mTc-hexakis 2-methoxy-2-isobutyl isonitrile and 201Tl SPECT imaging for evaluation of coronary artery disease

To evaluate clinical value of 99mTc-hexakis 2-methoxy-2-isobutyl isonitrile (MIBI) imaging for assessing coronary artery disease (CAD), 99mTc-MIBI SPECT imaging at post-exercise and at rest was compared with 201Tl SPECT imaging at post-exercise and 3 hours redistribution in 27 patients suspected with CAD. The sensitivities for detecting CAD patients were 94% (17/18) by both studies. The specificities were 71% (5/7) by 99mTc-MIBI and 57% (4/7) by 201Tl (p = NS). The sensitivities for detecting stenosed coronary arteries (greater than or equal to 75% stenosis) were also similar between 99mTc-MIBI (78%) and 201Tl (74%) (p = NS). The similar specificity values were obtained by 99mTc-MIBI (84%) and by 201Tl (82%) (p = NS). The patterns of abnormality (normal, ischemia and scar) were similar between 99mTc-MIBI and 201Tl images in 22 of the 25 cases (88%) and 117 of the 125 segments (94%). However, these patterns were occasionally different particularly in patients who received PTCA or CABG. Thus, 99mTc-MIBI SPECT imaging seems to be as accurate as 201Tl SPECT imaging for the detecting and evaluating CAD.     

Evaluation of ischemia by exercise stress Tl-201 myocardial SPECT in silent and symptomatic ischemia

Forty patients with ischemic heart disease confirmed by coronary arteriography were performed Tl-201 stress myocardial scintigraphy using SPECT. Fifteen patients had anginal attack during exercise Tl-201 myocardial perfusion study (symptomatic group), and 25 patients had horizontal or downsloping ST segment depression more than 0.1 mV without angina (asymptomatic group). The washout maps were derived from circumferential profile analyses of tomographic short-axis slices, and the data were plotted as a bull's eye map. The patient's washout map was compared with the lower limit of normal (mean--2 SD), and the extent and severity scores were calculated. On visual analysis 87% (13/15) of symptomatic patients showed redistribution, while only 56% (14/25) of asymptomatic patients showed redistribution (p less than 0.05). The extent score was significantly higher in the symptomatic group than in asymptomatic group (37.2 + 23.6 vs. 19.6 + 20.8, p less than 0.05), but severity score was slightly higher in symptomatic group (56.1 + 59.4 vs. 30.0 + 54.8, NS). In conclusion, symptomatic ischemia may be more severe than asymptomatic one and the degree of ischemia may be one of the factors that determine the presence of angina during ischemia.     

Diagnosis of extensive coronary artery disease: intrinisic value of increased lung 201 T1 uptake with exercise SPECT.

Exercise lung 201 TI uptake calculated with planar imaging has an important diagnostic and prognostic value in patients with coronary artery disease (CAD). However, its value with SPECT imaging raises methodological concerns and is controversial. We studied its value for the discrimination between extensive (E) and limited (L) angiographic CAD with exercise SPECT. METHODS: Four methods of lung-to-heart ratio quantification were calculated in patients with a low likelihood (< 5%) of CAD (n = 62). Their dependent variables were defined, and corresponding correction equations were derived. Receiver operating characteristic (ROC) analysis was performed in a pilot group (L-CAD, n = 49; E-CAD, n = 126) to define the optimal method of calculation of the lung-to-heart ratio. Its best threshold providing the best sensitivity for a specificity of 90% was defined. After correction for dependent variables, the 4 methods were also compared by ROC analysis and the optimal corrected method was compared with the optimal uncorrected method using ROC analysis and the best threshold. The consistency of these results in the validation group (L-CAD, n = 41; E-CAD, n = 122) and of the results of visual analysis of lung 201TI uptake were then verified. RESULTS: On ROC analysis in the pilot group, the optimal method of calculation of the lung-to-heart ratio was the mean activity in a region of interest drawn at the base of the lungs to the mean activity over the heart (Lb/H). For the best threshold, Lb/H presented a sensitivity of 34%. Corrected Lb/H still remained the best method of calculation on ROC analysis compared with the other corrected methods. On ROC analysis, there was no difference between corrected and uncorrected Lb/H. For the best threshold, corrected Lb/H presented a similar sensitivity of 37% compared with uncorrected Lb/H. When applied to the validation group (L-CAD, n = 41; E-CAD, n = 122), the best-defined threshold in the pilot group for corrected Lb/H presented a diagnostic value similar to that in the pilot group (sensitivity, 41%; specificity, 90%), but uncorrected Lb/H presented a higher sensitivity (47%; P < 0.04) and a slightly lower specificity (80%). Results of lung 201TI uptake visual analysis were inconsistent between pilot and validation groups (42% versus 58% sensitivity, P = 0.012; 86% versus 66% specificity, P = 0.023). CONCLUSIONS: For evaluation of E-CAD versus L-CAD, quantification of the exercise lung-to-heart 201TI uptake ratio with SPECT is feasible, reproducible, more discriminate than simple visual analysis, and best calculated as Lb/H. It presents an intrinsic diagnostic value even after correction for other clinically valuable dependent variables.     

Feasibility of simultaneous stress 99mTc-sestamibi/rest 201Tl dual-isotope myocardial perfusion SPECT in the detection of coronary artery disease.

This study assesses feasibility and diagnostic accuracy of simultaneous stress 99mTc-sestamibi/rest 201 TI dual-isotope myocardial perfusion SPECT with Moore's correction method, in which contamination originating from lead x-rays produced in a collimator was subtracted in the 201TI windows. METHODS: Eighty-one patients with suspected coronary artery disease received exercise 99mTc-sestamibi injection, followed by rest 201TI injection 50 min later, and dual-isotope SPECT was performed (group 1). These results were compared with coronary angiographic findings. Furthermore, to estimate the accuracy of Moore's correction method, 201TI crosstalk into the 99mTc acquisition window (group 2A, n = 20) and 99mTc crosstalk into the 201TI acquisition windows (group 2B, n = 20) were studied. For group 2A, stress 99mTc-sestamibi SPECT (single 99mTc-sestamibi SPECT) was performed, followed by 201TI injection at rest and dual-isotope SPECT acquisition 50 min later. For group 2B, rest 201TI SPECT (single 201TI SPECT) was performed, followed by 99mTc-sestamibi injection at rest and dual-isotope SPECT acquisition 30 min later. RESULTS: Sensitivity and specificity in group 1 were 83% and 99%, respectively, when > or =75% coronary artery narrowing was considered significant. In groups 2A and 2B, SPECT images were divided into 24 segments, and relative regional uptake in each segment was obtained. In group 2A, relative regional uptake of single 99mTc-sestamibi SPECT correlated well with that of dual-isotope SPECT (r = 0.942). In group 2B, relative regional uptake of single 201TI SPECT correlated well with that of dual-isotope SPECT (r = 0.935). Furthermore, in low 201TI uptake segments with relative regional uptake in both single- and dual-isotope SPECT of < or =70%, the degree of concordance between single- and dual-rest 201TI was considered to be high with Bland-Altman analysis and the kappa statistic. Comparison of perfusion defect type demonstrated that, of 22 stress defects within infarct zones, 95% were irreversible and 5% were reversible. In contrast, of 28 stress defects within stenosed vessel zones in noninfarct zones, 89% were reversible and 11% were irreversible (P < 0.0001 versus infarct zones). CONCLUSION: Simultaneous dual-isotope imaging with Moore's correction method is feasible, with acceptable accuracy for detection of coronary artery disease and a small amount of crosstalk into each window.     

Residual exercise SPECT ischemia on treatment is a main determinant of outcome in patients with coronary artery disease treated medically at long-term with ß-blockers

BACKGROUND: Beta-blockers are potent anti-ischemic medications, able to improve prognosis in patients with coronary artery disease (CAD). However, it is not known whether beta-blockers have the same beneficial prognostic effect when residual ischemia persists on treatment. METHODS AND RESULTS: The prognostic impact of exercise single photon emission computed tomography (SPECT) ischemia was analyzed in 442 patients with chronic CAD, who were treated with beta-blockers and who were referred to exercise thallium 201 SPECT, while they were receiving their daily-life medications. Ischemic and viable myocardium was documented on Tl-201 SPECT in 190 patients (43%), of whom only 23% had angina and only 26% had positive exercise testing results. During a follow-up of 3.8 +/- 1.7 years, 36 patients died and survival curves were progressively divergent between patients with and those without ischemic and viable myocardium: at 5 years, the respective survival rates were 81% +/- 4% and 94% +/- 2% (P =.004). By multivariate analysis, the best independent predictors of death were large extent of necrosis (>25% of left ventricle on Tl-201 SPECT, P <.001) and ischemic and viable myocardium (P =.001). CONCLUSIONS: In the CAD patients treated on a long-term basis with beta-blockers, survival is strongly influenced by persistent exercise SPECT ischemia on treatment. Therefore exercise SPECT on treatment could be a useful tool for selecting those who might benefit from additional anti-ischemic therapeutic interventions.     

Noninvasive estimation of site of lesion of left anterior descending artery with stress 201Tl myocardial SPECT images]

Noninvasive estimation of site of lesion of left anterior descending artery (LAD) is important because of high morbidity of LAD lesion. Utility of stress 201Tl myocardial SPECT images for predicting site of LAD lesion characteristics of ischemic region induced by LAD lesion in the basal coronal image were studied in 53 patients with localized significant LAD lesion. Right margin of ischemic region at basal plane of SPECT images was determined by circumferential maximum count profile analysis of stress 201Tl myocardial images. Right margin of ischemic region induced by the just proximal lesion was 21 +/- 11 degrees, that by proximal lesion was -6 +/- 10 degrees and that by mid portion was -36 +/- 17 degrees. Sensitivity of right margin of ischemic region 0 for just proximal lesion was 100% (20/20) and that of right margin of ischemic region 0 for mid portion lesion was 100% (18/18). These results showed the possibility of detecting site of LAD lesion by stress 201Tl myocardial SPECT images.     

运动试验心肌灌注显像诊断冠心病伴心房颤动的价值

目的评价运动试验心肌灌注显像诊断冠心病伴心房颤动（房颤）的能力。方法回顾性分析58例接受运动试验^99Tc^m-甲氧基异丁基异腈（MIBI）心肌灌注显像，且运动试验心电图示房颤心律的患者检查结果，并与冠状动脉造影结果比较。结果58例患者中，瓣膜性心脏病20例，非瓣膜性心脏病38例。运动试验心肌灌注显像诊断冠心病伴房颤患者的灵敏度、特异性和准确性分别为60％（9／15）、88％（38／43）和81％（47／58）。在非瓣膜性心脏病患者中，运动试验心肌灌注显像诊断冠心病的灵敏度和特异性分别为60％（9／15）和96％（22／23）；在瓣膜性心脏病患者中，运动试验心肌灌注显像的诊断准确性为80％（16／20）。结论运动试验心肌灌注显像诊断非瓣膜病房颤患者冠心病有中等程度的灵敏度和较高的特异性；诊断瓣膜病房颤患者冠心病有较高的准确性，但存在一定的假阳性。