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1.
T Miyakawa S Miura T Ichikawa I Motegi M Kato K Nakai T Takahashi T Yanagisawa 《Journal of cardiology》1989,19(4):1009-1015
To evaluate the diagnostic significance of exercise Tl-201 myocardial SPECT in silent myocardial ischemia, 41 patients with angiographically-proven coronary artery disease (27 effort angina, 14 post-infarction angina) were tested using this method. Double product (blood pressure x heart rate) during exercise was used as a hemodynamic parameter. Thirty-two projections were obtained throughout 180 degrees by a rotating gamma camera, immediately, and four hours after exercise. Myocardial Tl-201 washout rate of the entire left ventricle was presented in two-dimensional polar function maps. Normal lower limit of myocardial Tl-201 washout rate was defined as mean-2SD of normals, and the region with a washout rate lower than normal was defined as an ischemic region. The location of myocardial ischemia was visually determined using a Bull's eye polar map. The ischemic size was quantified by the defect volume ratio (ratio of the ischemic myocardium to total myocardium). Coronary lesions were quantitatively assessed by the Pujadas score using coronary angiography. Results were as follows: There was no significant difference between painful myocardial ischemia and silent myocardial ischemia according to double product and the Pujadas scores. In most silent ischemia, the region of the reduced washout rate was in the inferior or lateral area of the Bull's eye polar map, whereas it was in the anterior area in painful ischemia. The defect volume ratio indicating the extent of ischemia was smaller in silent ischemia than in painful ischemia. In conclusion, the ischemic location and size may be contributing factors in silent myocardial ischemia. 相似文献
2.
M Okano F Ohsuzu S Katsushika S Yanagida M Senoo N Aosaki H Nakamura 《Journal of cardiology》1990,20(3):571-581
To diagnose and characterize post-infarction left ventricular aneurysms, we performed exercise thallium-201 myocardial single photon emission computed tomography (SPECT) combined with selective coronary angiography and left ventriculography. The subjects consisted of 79 patients with acute myocardial infarction; 42 with anteroseptal, three with both anterior and inferior, 29 with inferior and five with posterior infarction. Visual classification of ventricular wall morphology by either a horizontal or a vertical long-axis image was designed into convergent (C), parallel (P) and divergent (D) types, according to the interrelationship between either septal and lateral wall or anterior and inferior wall, respectively. This method was applied in post-stress and delayed images, and these patients were divided into five groups (Group A-E) in accordance with varying morphological types from the post-stress to the delayed as follows: C-C (Group A, 36 patients), P-C (Group B, 8), P-P (Group C, 7), D-P (Group D, 5) and D-D (Group E, 23). A high incidence (21/23) of a left ventricular aneurysm by left ventriculography was recognized in Group E patients in comparison with other Groups. Provided that either Group D or E (all patients had anterior infarction) had left ventricular aneurysms, the diagnostic sensitivity, specificity and accuracy were 89%, 92% and 86%, respectively. Two of three patients with false negative diagnosis had only apical involvement. Furthermore, these two Groups had significantly larger defect scores as calculated by polar maps than did the other three Groups. When patients with anterior infarction with defect scores of 200 or greater were defined positive, the sensitivity, specificity and accuracy of ventricular aneurysms were 96%, 75% and 86%, respectively. One false negative case was apical infarction, and one of the two false positive cases were extensive anteroseptal infarction involving the apex. These results suggest that a left ventricular aneurysm which is important in predicting prognostic sequence could be diagnosed only by exercise SPECT, and that it could be characterized by extensive and severe apicoanterior infarction and a divergent-type ventricular wall arrangement on a post-stress SPECT image. 相似文献
3.
This study evaluated the performance of gated single photon emission computed tomography (SPECT) with thallium-201 (201Tl) in assessing left ventricular ejection fraction (LVEF), end-diastolic volume (EDV), and end-systolic volume (ESV) in Taiwanese by determining repeatability and correlation with two-dimensional (2D) echocardiography. A total of 18 patients underwent two sequential gated SPECT acquisitions within 30 minutes in the resting state to assess repeatability. Another 28 patients who underwent gated SPECT and 2D echocardiography within 7 days were included for comparison. The two sequential measurements were well correlated with respect to LVEF, EDV, and ESV (r = 0.97, 0.95, and 0.97, respectively, all p < 0.0001). Bland-Altman analysis revealed that two standard deviations of the absolute difference between the two sequential measurements for LVEF, EDV, and ESV were 6.4%, 16.8 mL, and 8.6 mL, respectively. For LVEF, EDV, and ESV, correlations between redistribution 201Tl-gated SPECT and echocardiography were also excellent (all r = 0.83, p < 0.0001). LVEF was similar with 201Tl-gated SPECT and echocardiography, but EDV and ESV were significantly higher with echocardiography (p < 0.05). Our study revealed that 201Tl-gated SPECT has high repeatability and excellent correlation with echocardiography for the assessment of LVEF and volumes in Taiwanese. These results support the clinical application of gated SPECT in routine 201Tl myocardial perfusion imaging in Taiwanese. 相似文献
4.
K G Cloninger E G DePuey E V Garcia G S Roubin W L Robbins A Nody E E DePasquale H J Berger 《Journal of the American College of Cardiology》1988,12(4):955-963
To determine if incomplete redistribution at 4 h in exercise tomographic thallium-201 studies is always due to a myocardial scar, 141 patients were evaluated before and after a total of 160 successful percutaneous transluminal coronary angioplasty procedures. Thallium studies were analyzed using polar "bull's-eye" maps. For both immediate and delayed images, abnormalities were quantified as a thallium score by calculating a standard deviation-weighted sum of pixels greater than 2.5 SD below gender-matched normal limits. One hundred forty-four of 160 studies indicated abnormalities before angioplasty. Of these 144, incomplete redistribution occurred in 111 (77%): 16 (14%) in patients with and 95 (86%) in patients without prior Q wave myocardial infarction. After angioplasty, improvement in delayed image score occurred in 8 (50%) of 16 patients with prior infarction and 72 (76%) of 95 patients without prior infarction (p less than 0.05). After angioplasty, delayed images were normal in 1 (6%) of 16 patients with prior infarction and 32 (34%) of the 95 without (p less than 0.05). Before angioplasty, delayed image scores were positively correlated with scores in the immediate postexercise images in patients with (r = 0.84) and those without (r = 0.69) prior infarction. To determine if additional delayed images could help differentiate scar from ischemia, an 8 to 24 h delayed image was obtained in each of 40 other patients with incomplete redistribution at 4 h. Of 28 patients without prior infarction, 15 had no redistribution, and 13 had further redistribution at 8 to 24 h. 相似文献
5.
目的探讨心肌潘生丁负荷/再分布铊(T1)^201单光子发射计算机断层显像(single photon emission computed tomography,SPECT)法评价隐匿性冠心病预后的可行性。方法入选1998至2005年期间94例无任何症状但运动平板试验反复阳性的飞行人员,根据SPECT心肌显像结果分为检查结果阳性组及阴性组,阳性组中根据心肌缺血累及范围又分为单个节段受累亚组、2个节段受累亚组和2个以上节段受累亚组,平均随访4.5年,比较组间的主要心血管事件(major adverse cardiovascular events,MACE)发生率。结果随访过程中,阳性组与阴性组的MACE分别为30%与7%,差异具有统计学意义(P〈0.01)。2个以上节段受累亚组组MACE发生率(100%)明显高于单个节段受累亚组(24%)、2个节段受累亚组(22%)及阴性组(7%),P均〈0.05。结论潘生丁负荷心肌T1^201-SPECT显像有助于隐匿性冠心病预后判断,从而指导临床早期干预治疗。 相似文献
6.
A circumferential profile analysis with a two-dimensional polar representation of thallium(Tl)-201 myocardial single photon emission computed tomograms (SPECT) is an objective and quantitative method to evaluate myocardial infarction (MI). However, the diagnostic capability depends on the normal range of thallium distribution. Therefore, the quantitative analysis of Tl-201 myocardial SPECT was correlated with the pathological findings of the heart in 50 autopsy cases (28 with MI; 22 without MI) to determine the lower normal limits at which we can precisely determine the extent of MI on a quantitative basis. For correctly detecting the extent of MI, the lower normal limits were 2.5 standard deviations below the mean values calculated using profiles normalized to the maximum pixel count observed in each profile. Using this lower normal limit, the sensitivity was 63.8%; specificity was 87.4%; and accuracy was 80.7% for determining the extents of ischemic lesions, though these values were lower than those obtained by visual analysis. However, for detecting MI, the sensitivity by quantitative analysis was 97% which was higher than that by visual analysis. A medium sized (2.5 cm) non-transmural infarction, undetectable by visual analysis, was detectable by two-dimensional polar representations. However, the specificity of detecting MI was low (59%), and most of the false positive studies were observed in cases of valvular disease, coronary artery disease or other cardiac complications. The detectability of the extent of MI varied according to the location of the lesion. False negative lesions were most frequently observed in the septal region; false positive lesions were most frequently observed at the posterolateral regions of the dilated hypertrophic hearts. The septal region located at the peripheral portion of the MI and septal hypertrophy in cases of hypertension, were the likely negative cases, thus, these pathological characteristics may explain the high incidence of false negative results in the septal region quantitatively as well as by visual analysis. In cases with dilated hearts, the radioactivity of the thallium at the posterolateral region was more reduced by absorption compared with that in the non-dilated hearts. This reduction in counts was empirically regarded as abnormal lesions by visual analysis, however, the same situation can objectively and automatically be recognized as false positive by quantitative analysis. We concluded that quantitative analysis by Tl-201 myocardial SPECT is useful for evaluating myocardial infarction automatically, but care must be exercised concerning possible false positive diagnosis in cases with dilated hypertrophic hearts. 相似文献
7.
Exercise four hour redistribution thallium-201 single photon emission computed tomography and exercise induced ST segment elevation in detecting the viable myocardium in patients with acute myocardial infarction 总被引:3,自引:0,他引:3 下载免费PDF全文
Yamagishi H Akioka K Takagi M Tanaka A Takeuchi K Yoshikawa J Ochi H 《Heart (British Cardiac Society)》1999,81(1):17-24
OBJECTIVE: To investigate the specificity and sensitivity of the combination of redistribution in exercise thallium-201 single photon emission computed tomography (SPECT) and exercise induced ST elevation for detecting the viable myocardium in patients with acute myocardial infarction. DESIGN: 37 patients were studied within seven weeks of onset of Q wave myocardial infarction (anterior in 22, inferior in 15). All patients underwent exercise four hour redistribution thallium-201 SPECT and positron emission tomography using fluorine-18-fluorodeoxyglucose (FDG) and nitrogen-13 ammonia under fasting conditions. RESULTS: Sixteen patients showed exercise induced ST elevation >/= 1.5 mm, and 15 of these had increased FDG uptake in the infarct region. Eleven of 16 patients (10 of 11 patients with anterior infarctions) with irreversible thallium-201 defects and increased FDG uptake showed exercise induced ST elevation. The sensitivity, specificity, and predictive accuracy of redistribution, exercise induced ST segment elevation, or both for detecting increased FDG uptake were 82%, 75%, and 67% (94%, 75%, and 91% for anterior infarctions), respectively. CONCLUSIONS: In patients with acute Q wave myocardial infarction, the combination of redistribution in exercise thallium-201 SPECT and exercise induced ST elevation can detect the viable myocardium in the infarct region with high sensitivity and specificity, especially in patients with anterior infarctions. 相似文献
8.
Maruyama Y Kato T Ito H Tanaka S Yoshimoto N Kishi Y Numano F 《Japanese circulation journal》1999,63(3):155-159
A new method was devised to estimate infarct size using dual single photon emission computed tomography with thallium-201 and technetium-99m pyrophosphate. Designating the ratio of infarct area to whole myocardial volume as %MI, the correlation of %MI with other markers of left ventricular dysfunction was examined: peak creatine kinase, ejection fraction and left ventricular asynergy. As %MI correlated well with these markers, it is considered that %MI will be useful for estimating infarct size and predicting the severity of left ventricular dysfunction in the early stage of acute myocardial infarction. 相似文献
9.
Visualisation of exercise-induced ischaemia of the right ventricle by thallium-201 single photon emission computed tomography. 下载免费PDF全文
OBJECTIVE: Exercise thallium-201 (201T1) single photon emission computed tomography (SPECT) has been used to detect potential ischaemia in the left ventricular myocardium but not in the right ventricle. The purpose of this study was to establish the clinical usefulness of a right ventricular polar map of 201T1 SPECT for visualisation of exercise-induced right ventricular ischaemia. METHODS: Myocardial 201T1 SPECT was obtained immediately after treadmill exercise in 97 patients with suspected coronary artery disease. A region of interest was placed over the right ventricle (RV) on post-stress transaxial images. Short axis images of this region were generated and reconstructed as a bull's eye polar map. Normal ranges of RV 201T1 uptake were determined in 12 patients with normal coronary arteries. Scintigraphic criteria for identifying RV perfusion abnormality were derived from 25 patients with right coronary artery (RCA) stenosis greater than 75%. These criteria were applied to 60 consecutive patients with suspected coronary artery disease. RESULTS: Perfusion defects in the RV were larger in patients with proximal RCA stenosis than in those with distal RCA stenosis (mean (SD) 28 (16)% v 6 (5)%, P < 0.001). The sensitivity and specificity of the RV polar map for the detection of proximal RCA stenosis were 67% (8/12) and 98% (47/48), respectively. RV perfusion defects became undetectable in 9 patients who had successful percutaneous transluminal coronary angioplasty to a proximal RCA lesion. CONCLUSIONS: A right ventricular polar map display was useful for visualising exercise-induced right ventricular ischaemia. 相似文献
10.
K Kugiyama H Yasue K Okumura K Minoda K Takaoka K Matsuyama A Kojima Y Koga M Takahashi 《The American journal of cardiology》1987,60(13):1009-1014
Thallium-201 myocardial scintigraphy with quantitative analysis of emission computed tomography was performed during episodes of angina in 19 patients with variant angina and nearly normal coronary arteriographic findings. Eleven patients (group I) were shown by arteriography to have spasm in 2 or more large coronary arteries. Eight patients (group II) had spasm in only 1 coronary artery. In 7 patients in group I, significant diffuse perfusion defects simultaneously appeared in multiple coronary artery regions on the scintigram (group IA). The extent and severity of the perfusion defect as measured by thallium-201 tomography were significantly greater in group IA than in group II (p less than 0.001 and p less than 0.01, respectively). The duration of transient ST-segment elevation during the attack in group IA was significantly longer than in group II (p less than 0.001). The incidence of ventricular arrhythmias, including ventricular tachycardia, or complete atrioventricular block during the anginal attack was significantly higher (p less than 0.05) in group IA than in group II. In all study patients, neither attack nor scintigraphic perfusion defect appeared on the repeat test after oral administration of nifedipine. In conclusion, multivessel coronary artery spasm simultaneously appears and causes the attack in many patients with variant angina and nearly normal coronary arteriographic findings, and myocardial ischemia due to simultaneous multivessel coronary spasm is likely to be more extensive and severe, persist longer and have a higher frequency of potentially dangerous arrhythmias than that due to spasm of only 1 coronary artery. 相似文献
11.
Quantitative exercise thallium-201 single photon emission computed tomography for the enhanced diagnosis of ischemic heart disease 总被引:5,自引:0,他引:5
J J Mahmarian T M Boyce R K Goldberg M K Cocanougher R Roberts M S Verani 《Journal of the American College of Cardiology》1990,15(2):318-329
The clinical utility of exercise thallium-201 single photon emission computed tomography was investigated in 360 consecutive patients who had concomitant coronary arteriography. Tomographic images were assessed visually and from computer-quantified polar maps. Sensitivity for detecting coronary artery disease was comparably high using quantitative and visual analysis, although specificity tended to improve using the former method (87% versus 76%, p = 0.09). Quantitative analysis was superior to the visual method for identifying left anterior descending (81% versus 68%, p less than 0.05) and circumflex coronary artery (77% versus 60%, p less than 0.05) stenoses and detected most patients (92%) with multivessel coronary artery disease. Multivessel involvement was correctly predicted in 65% of the patients with more than one critically stenosed vessel. Exercise variables in patients with significant coronary artery disease were similar whether the tomographic images were normal or abnormal. However, patients with coronary stenoses and normal versus abnormal tomograms had a trend toward more single vessel disease (79% versus 62%, p = 0.07) and moderate coronary stenosis (66% versus 28%, p less than 0.001), but had less proximal left anterior descending artery involvement (8% versus 34%, p = 0.05). Computer-quantified perfusion defect size was directly related to the extent of coronary artery disease. Intra- and interobserver agreement for quantifying defects were excellent (r = 0.98 and 0.97, respectively). In conclusion, quantitative thallium-201 tomography offers improved detection of coronary artery disease, localization of the anatomic site of coronary stenosis, prediction of multivessel involvement and accurate determination of perfusion defect size, while maintaining a high specificity. Quantification of perfusion defects with single photon tomography may become important for assessing the effects of coronary reperfusion and prognostically stratifying patients with coronary artery disease. 相似文献
12.
In a series of 12 dogs having an acute experimental anteriormyocardial infarct, the size of the infarct was measured using,successively, single photon emission transaxial tomography (SPETT)with thallium-201, conventional planar scintigraphy of the anatomicslices, and planimetry of these slices after nitroblue-tetrazolium(NBT) staining. The tomographic views were obtained after processingof projection images collected during the rotation of a scintillationcamera around the animals. A correlation of 0.86 was obtainedbetween SPETT and NBT staining for the whole series, and a valueof 0.94 was observed when only the transmural infarcts wereconsidered. These results suggest that SPETT of the myocardiumlabelled with thallium-201 should allow a reliable, rapid andatraumatic estimation of the infarct size. 相似文献
13.
Zhu H Hozumi T Takemoto Y Takagi Y Negishi K Abo K Sugioka K Matsumura Y Otsuka R Yoshitani H Nakao M Yoshiyama M Yoshikawa J 《Journal of cardiology》2006,47(4):165-172
OBJECTIVES: The feasibility of detecting persistent regional left ventricular abnormal relaxation due to myocardial ischemia using strain echocardiography several minutes after exercise was investigated. METHODS: Consecutive 27 patients (mean age 65 +/- 9 years, 21 males, 6 females) with suspected coronary artery disease were enrolled. Strain echocardiographic images were acquired at the mid segments of the left ventricular wall before and 5 min after exercise in the apical long-axis, two-chamber and four-chamber views. Strain curves were obtained at each segment, and peak values of strain at the closure of aortic valve (A) and at one third of diastolic duration (B) were measured. Strain diastolic index (SDI) was calculated as (A - B)/A X 100%. The ratio of SDI before exercise to that after exercise was defined as the SDI ratio and compared with exercise thallium-201 single photon emission computed tomography (SPECT) as the reference standard to detect myocardial ischemia. RESULTS: A total of 162 segments were evaluated. Based on the results of exercise SPECT, 119 segments were classified as non-ischemic segments, and 43 as ischemic segments. Ischemic segments showed significant decreases in SDI before and after exercise, whereas non-ischemic segments showed no significant differences in SDI before and after exercise. SDI ratio was significantly decreased in ischemic segments, but not in non-ischemic segments. SDI ratio with a cut off value of 0.51 had a sensitivity of 91% and a specificity of 89% to detect myocardial ischemia in the receiver-operating characteristics. Conclusions. Strain echocardiography can provide quantitative assessment of myocardial ischemia by detecting post-ischemic regional left ventricular delayed relaxation even 5 min after exercise. 相似文献
14.
H Yamagishi H Itagane K Akioka T Ohmura H Iida A Tahara I Toda M Teragaki K Takeuchi T Takeda 《Japanese circulation journal》1992,56(11):1095-1105
To determine the clinical significance of reverse redistribution (RR), resting thallium-201 myocardial single-photon emission computed tomography was performed once or twice in 80 patients in subacute phase (1 week to 2 months) of myocardial infarction. Thirty eight patients demonstrated RR on at least one study (group RR) and 32 a fixed defect only (group FD). Group RR had significantly smaller defects than group FD. Standardizing the relation of the severity of wall motion abnormality of left ventricle on echocardiogram with that of perfusion defect, in group RR wall motion abnormality in the acute and subacute phase reflected the defect of delayed image, while that in chronic phase, which was thought to reflect the viability of myocardium in the infarct region, reflected the defect of initial image. In serial thallium-201 studies, only the defect of delayed image of group RR improved on the second study, while the defect of initial image of group RR and defect of group FD did not improve. Wall motion of group RR improved with the disappearance of RR, and when RR remained, wall motion did not improve so much. We concluded that RR was thought to be demonstrated in viable myocardium with severe wall motion abnormality. 相似文献
15.
A M Amanullah F A Chaudhry J Heo K Galatro P Dourdoufis S Brozena J Narula A E Iskandrian 《The American journal of cardiology》1999,84(6):626-631
Both dobutamine stress echocardiography (DSE) and myocardial perfusion scintigraphy are used to assess myocardial viability. Few studies have compared the data on myocardial viability and ischemia by low and peak dose DSE and myocardial perfusion imaging in the same patients. Fifty-four patients (45 men and 9 women aged 65 +/- 9 years) with ischemic cardiomyopathy (mean ejection fraction 24 +/- 9%) underwent rest 4-hour redistribution thallium-201 single-photon emission computed tomography (SPECT), low and peak dose DSE, and dobutamine sestamibi SPECT. A total of 864 segments were analyzed (16 segments/patient). Wall motion abnormality was present in 796 segments (92%), and contractile reserve during dobutamine infusion was seen in 400 of these segments (50%). Contractile reserve was seen in 331 of 509 hypokinetic segments (65%) and 69 of 287 akinetic/dyskinetic segments (24%) (p <0.001). Contractile reserve was more frequent in segments with normal thallium uptake (64%), reversible thallium defects (42%), or mild to moderate fixed thallium defects (48%) than severely fixed defects (22%) (p <0.05 each). Concordant information about viability by thallium imaging and DSE was obtained in 62% of segments. Dobutamine sestamibi ischemia was seen in 518 of 796 segments (65%) compared with 265 segments (33%) by DSE (p <0.001). Scintigraphic ischemia was noted in 126 of 195 segments (65%) demonstrating biphasic response, 129 of 205 segments (63%) showing sustained improvement, 42 of 70 segments (60%) deteriorating during dobutamine infusion, and 221 of 326 (68%) demonstrating no change (p = NS). Thus, in patients with ischemic cardiomyopathy, contractile reserve is more frequent in hypokinetic segments than akinetic/dyskinetic segments. The number of segments with normal or near-normal thallium uptake or with scintigraphic ischemia is significantly greater than the number of those capable of increasing contractile function or demonstrating an ischemic response during dobutamine echocardiography. 相似文献
16.
A Jain J J Mahmarian S Borges-Neto D L Johnston W R Cashion J M Lewis A E Raizner M S Verani 《Journal of the American College of Cardiology》1988,11(5):970-976
The clinical significance of myocardial perfusion defects present early after angiographically successful percutaneous transluminal coronary angioplasty was assessed in 53 patients using thallium-201 single photon emission computed tomography combined with pharmacologic vasodilation induced by a large dose (300 mg) of orally administered dipyridamole. Myocardial tomographic images were obtained at a mean of 20 +/- 6 h (SD) before and 2.9 +/- 2.7 days after angioplasty. Before angioplasty, 15 (28%) of the 53 patients developed angina after dipyridamole administration, in contrast to only 3 (7.5%) of 40 patients after angioplasty (p less than 0.001). The mean percent luminal area stenosis decreased from 93 +/- 6% before angioplasty to 34 +/- 17% after angioplasty (p less than 0.001). Myocardial perfusion defects, present in 49 (93%) of the 53 patients before angioplasty, were reversible in 44 patients (83%), all of whom underwent dilation of arteries supplying the ischemic areas. After angioplasty, 26 (65%) of 40 patients had no ischemic defects, whereas 14 (35%) of the patients still had an ischemic defect in the vascular territory of the dilated artery. After a mean follow-up period of 21.7 months, 13 (33%) of 39 patients developed restenosis, 10 of whom had an ischemic defect early after angioplasty. Restenosis developed in 10 (71%) of 14 patients with an ischemic defect after angioplasty, but in only 3 (11.5%) of the patients without an ischemic defect (p = 0.007). In conclusion, thallium-201 tomography after oral dipyridamole affords convenient assessment of the physiologic significance of coronary stenosis present before angioplasty and the residual stenosis after angioplasty.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
17.
Fujimoto K Watanabe H Hozumi T Otsuka R Hirata K Yamagishi H Yoshiyama M Yoshikawa J 《Journal of cardiology》2004,43(3):109-116
OBJECTIVES: The usefulness of coronary flow reserve measurement in the left circumflex coronary artery by transthoracic Doppler echocardiography to detect myocardial ischemia was compared with exercise thallium-201 single photon emission computed tomography (SPECT). METHODS: Transthoracic Doppler echocardiography was performed in 110 patients with suspected coronary artery disease. Color Doppler signals of the left circumflex coronary artery flow in the apical four-chamber view were identified, and the velocities at rest and during hyperemia recorded for calculation of coronary flow reserve by the pulsed Doppler method. All patients underwent SPECT within 1 week of the transthoracic Doppler echocardiographic study. RESULTS: Coronary flow reserve in the left circumflex coronary artery was measured in 79 (72%) of 110 patients. SPECT revealed reversible perfusion defect in the left circumflex coronary artery territories in 12 of 69 patients excluding those with multivessel disease. Coronary flow reserve < 2.0 had a sensitivity of 92% and specificity of 96% for reversible perfusion defect detected by SPECT. CONCLUSIONS: Noninvasive coronary flow reserve measurement in the left circumflex coronary artery by transthoracic Doppler echocardiography can estimate myocardial ischemia in the left ventricular lateral regions. 相似文献
18.
The diagnostic usefulness of predischarge exercise echocardiography in 35 patients with unstable angina who responded to medical therapy was correlated with exercise thallium-201 single photon emission computed tomography (TI-SPECT) performed, on the average, three days after the exercise echocardiography. None of the patients had myocardial infarction prior to hospitalization or before TI-SPECT and none had left bundle-branch block on their rest electrocardiogram (ECG). Exercise echocardiography was positive in 21 patients and TI-SPECT in 24. The results of the two techniques were concordant in 28 of 35 patients (agreement = 80%, k = 0.57 +/- 0.14, p less than 0.001). Wall-by-wall comparison of the distribution of exercise-induced wall motion abnormalities with reversible thallium defects showed complete or partial correlation in all of 19 patients in whom both the tests were positive. A positive exercise ECG and positive exercise echocardiography identified 11 of 11 patients with angiographically verified significant coronary artery disease (CAD) and 11 of 12 patients (92%) with positive TI-SPECT. Thus, exercise echocardiography is a valuable addition to routine predischarge exercise test in the noninvasive diagnosis of myocardial ischemia and shows a good correlation with TI-SPECT in detecting and localizing ischemia in patients with unstable angina stabilized on medical therapy. 相似文献
19.
Hosokawa R Nohara R Linxue L Tamaki S Hashimoto T Tanaka M Miki S Sasayama S 《Japanese circulation journal》2000,64(3):177-182
Fifteen patients with either angina pectoris or old myocardial infarction, who had positive 201Tl single photon emission computed tomography (SPECT) imaging and coronary sclerosis of more than 50%, were treated with an HMG-CoA reductase inhibitor (simvastatin) for more than 1 year. They were compared with an untreated control group (n = 25). Total cholesterol decreased 22% and high-density lipoprotein (HDL) increased 9% with simvastatin; both changes were significantly different from those in controls. Long-term simvastatin induced improvement of myocardial perfusion on 201Tl SPECT images both during exercise and at rest, which was also significantly different from controls. In addition, the improvement of myocardial perfusion on 201Tl SPECT images was clearly related to the improvements in cholesterol values, especially nonHDL cholesterol. Thus, the greater the decrease in nonHDL cholesterol, the greater the improvement in myocardial perfusion at rest or during exercise with long-term treatment using an HMG-CoA reductase inhibitor. These findings indicate that the improvements in cholesterol values caused by HMG-CoA reductase inhibitor therapy are related to improvements of myocardial perfusion seen on 201Tl SPECT images. 相似文献
20.
While the interpolative background subtraction used in quantitative planar thallium scanning can significantly overestimate the background overlying the heart, the effects of background oversubtraction on quantitative analysis have not been well defined. A mathematical model that relates myocardial washout determined using interpolative background subtraction to true myocardial washout is presented. The model was validated using phantoms and applied to myocardial and pulmonary thallium kinetic data in 100 patients, 85 with and 15 without coronary artery disease. The model showed that when using interpolative background subtraction, measured washout equals true washout in normally perfused myocardium; however, depending on the relation between myocardial and pulmonary thallium clearance, myocardial washout in ischemic regions and areas of infarction can be substantially over- or underestimated. Based on generally accepted quantitative criteria, this incorrect washout determination can at times lead to misdiagnosis of infarction as ischemia and ischemia as normally perfused tissue. It can also cause both "reverse redistribution" and "pseudo redistribution" of thallium in myocardial infarction in the absence of a physiologic basis. 相似文献