Thallium-201 SPECT and low-dose dobutamine stress cine MRI for predicting functional recovery of regional myocardial contraction in patients with myocardial infarction.

OBJECTIVES: The purpose of this study was to compare the diagnostic performances of Tl-201 single photon emission computed tomography (SPECT) and dobutamine stress cine magnetic resonance imaging (MRI) for predicting functional recovery of regional myocardial contraction in patients after myocardial infarction. METHODS: Twenty patients underwent Tl-201 SPECT and MRI 3-4 weeks after onset of myocardial infarction. Cine MR images were acquired in the resting state and during dobutamine stress. Tl-201 uptake and systolic wall thickening (SWT) on cine MRI were analyzed on short-axis images by using a 14-segment model. Follow-up cine MR images were obtained 187.1+/-33.5 days after onset. RESULTS: The averaged Tl-201 uptake in 54 segments with impaired SWT was 47%+/-20%, being significantly lower than that in 226 segments with preserved SWT (75%+/-18%; p<0.0001). The sensitivity, specificity, and accuracy of dobutamine MRI and Tl-201 SPECT for predicting preserved SWT after 6 months were 89% vs. 80%, not significant (NS); 89% vs. 72%, p<0.01; and 89% vs. 79%, NS, respectively. In the anterior wall and apex, the sensitivity and specificity of SPECT were not significantly different from those of MRI. In the inferior wall and posterolateral wall, however, the specificity of SPECT was substantially lower than that of MRI (53% vs. 88%, p<0.001), resulting in significantly lower accuracy (75% vs. 90%, p<0.01). CONCLUSIONS: Both SPECT and dobutamine MRI showed excellent sensitivity for predicting myocardial viability in all left ventricular segments. Decreased specificity of SPECT in the inferior and posterolateral segments resulted in lower overall specificity in comparison with dobutamine MRI.     

Biphasic response to dobutamine predicts improvement of left ventricular dysfunction after revascularization: correlation with positron emission and rest-redistribution 201Tl tomographies

BACKGROUND: Dobutamine echocardiography (DSE), positron emission tomography (PET) and 201Tl-single photon emission computed tomography (SPECT) have been used to identify myocardial viability. There are few reports, however, that compare high doses DSE with myocardial metabolic and perfusion imaging techniques in the same patient population. The aim of this study was to determine the correlation between high doses DSE, metabolic PET and 201Tl-SPECT imaging to predict the recovery of function after revascularization in patients with severe left ventricular (LV) dysfunction. METHODS: Twenty-five patients underwent DSE (up to 40 microg/kg/min), rest and 4-hour redistribution 201Tl SPECT, rest 13N-ammonia and 18fluoro-deoxy-glucose PET imaging and coronary angiography 7-10 days before surgical revascularization. A follow-up 2D-echocardiography was performed 6 weeks after surgery. RESULTS: Of the 109 successfully revascularized segments with severe dysfunction, 62 (57%) improved. LV ejection fraction increased from 30 +/- 10% to 42 +/- 13 at follow-up (p < 0.05). 201Tl SPECT, PET and the presence of contractile reserve determined by DSE had a similar sensitivity (77-87%) to predict recovery of function, but specificity was higher for the PET mismatch pattern and biphasic DSE (85-89%) than for any of the 201Tl viability patterns (19-64%). The highest positive predictive values were obtained by biphasic DSE and PET mismatch pattern (78-79%) compared to all other criteria (54-67%). In a multivariate model, which included evidence of viability by all imaging modalities, biphasic response was the best predictor of regional recovery of function (Odds ratio, OR: 9.9, 95% confidence intervals, 95% CI: 3.5-27.8). CONCLUSIONS: Although DSE and PET had overall comparable results, the presence of contractile reserve by the biphasic response to dobutamine was a best predictor for the improvement of LV contractile function in this group of patients.     

应变显像评价ST段抬高急性心肌梗死患者存活心肌的敏感性与特异性

目的 比较应变显像(SI)与静息-再分布201Tl心肌灌注显像(RR-201Tl-SPECT)预测ST段抬高的急性心肌梗死(AMI)患者存活心肌的敏感性与特异性.方法 对26例AMI患者进行介入治疗1周后行超声心动图和RR-201Tl-SPECT检查,并随访治疗≥3个月后的超声心动图.测量左室长轴16节段的应变及RR-201 Tl-SPECT心肌灌注评分,以1周和≥3个月的室壁运动评分(WMS)对比作为判定存活心肌的"金标准".结果 ①共研究260个缺血节段.随访(5±2)月,据WMS判定存活节段201个,梗死节段59个.RR-201 Tl-SPECT预测存活心肌的敏感性和特异性为87%(175/201)和58%(34/59).②以收缩期应变(Set)＜-6%为最佳截止点预测存活心肌的敏感性和特异性分别为81%(161/201)和66%(39/59).③Set与RR-201 Tl-SPECT总符合率77%(199/260),具有中等一致性(Kappa=0.40).结论 S1评价ST段抬高AMI患者的存活心肌是可行的,其与RR-201 Tl-SPECT显像诊断效力相似,是更简便、无创、低成本的替代选择.     

Factors Affecting Accuracy of Ventricular Volume and Ejection Fraction Measured by Gated Tl-201 Myocardial Perfusion Single Photon Emission Computed Tomography

The electrocardiogram-gated single photon emission computed tomography (SPECT) measurement of left ventricular end-diastolic volume, end-systolic volume and ejection fraction may contain substantial errors. We evaluated whether patient-related factors affect the accuracy of left ventricular volume and ejection fraction measured by gated Tl-201 SPECT. A total of 518 patients without perfusion defects on Tl-201 SPECT or coronary artery disease were studied. Left ventricular volume and ejection fraction were measured from echocardiography and adenosine stress/redistribution gated Tl-201 SPECT using commercially available software packages (QGS and 4D-MSPECT). We identified factors affecting the accuracy of gated SPECT via multiple linear regression analysis of the differences between echocardiography and gated SPECT. Gated SPECT analyzed with QGS underestimated end-diastolic and end-systolic volume, and overestimated ejection fraction, but 4D-MSPECT overestimated all those values (P<0.001). Independent variables associated with increasing the difference in end-diastolic volume between echocardiography and gated SPECT were decreasing left ventricular end-diastolic wall thickness, decreasing body surface area, female sex and increasing end-diastolic volume (P<0.001). Those for end-systolic volume were decreasing left ventricular end-systolic wall thickness, female sex, and decreasing end-systolic volume (P<0.001). Increasing end-systolic wall thickness, male sex and decreasing age were independent determinants associated with an increased difference in ejection fraction (P<0.001). Adenosine stress SPECT showed significantly higher end-diastolic and end-systolic volume values and a lower ejection fraction than did redistribution SPECT (P<0.001). Patient-related factors affect the accuracy of left ventricular volume and ejection fraction measured by gated Tl-201 SPECT. Modification of gated SPECT measurements by taking account of these factors would lead to reduce systemic errors.The authors do not have any financial associations that might pose a conflict of interest in connection with the submitted article. None of the authors has a financial interest in any cardiac software package, and this study was not supported by any vendor or cardiac software producer.     

Left ventricular involvement in arrhythmogenic right ventricular cardiomyopathy - a scintigraphic and echocardiographic study

BACKGROUND: Left ventricular involvement in arrhythmogenic right ventricular cardiomyopathy (ARVC) is a common finding in autopsy studies. In clinical studies using myocardial scintigraphy, MRI and echocardiography, contradictory results have been reported. In this study, we therefore investigated a group of 15 patients with ARVC using thallium-201 (Tl) single-photon emission tomography (SPECT) and echocardiography including assessment of mitral annular motion with M-mode and pulsed tissue Doppler. METHODS: Exercise and rest Tl-201 SPECT were performed in 15 patients with ARVC. The time from diagnosis of the disease varied from less than 1-16 years. All patients fulfilled the established diagnostic criteria for ARVC. An echocardiographic examination, including assessment of left and right ventricular motion and measurements of the mitral annulus motion with M-mode and pulsed tissue Doppler was performed in the patients and in 25 normal subjects. RESULTS: Tl-201 uptake defects in the left ventricular myocardium were present in all except one patient (93%). The uptake defects were predominantly located to the anteroseptal and basal posterior segments. Wall motion abnormalities were seen in the same segments, and in addition to this, in the septal area. In line with this, the total amplitude and the peak systolic velocity of mitral annular motion at the septal point were significantly decreased in the patients compared with the control group. CONCLUSIONS: Our data show that left ventricular involvement is common in ARVC. Tl-201 SPECT and echocardiographic abnormalities were seen not only in patients with long-lasting symptoms but also in asymptomatic patients and in those with short duration of symptoms.     

Head-to-head comparison of contrast-enhanced cardiovascular magnetic resonance and (201)Thallium single photon emission computed tomography for prediction of reversible left ventricular dysfunction in chronic ischaemic heart disease

Delayed contrast-enhanced cardiovascular magnetic resonance (DE-CMR) allows assessment of reversibility of myocardial dysfunction. Comparative data to other modalities is scarce. Purpose of this study was to compare DE-CMR and (201)Thallium single photon emission computed tomography (SPECT) for prediction of reversible left ventricular (LV) dysfunction in patients with chronic ischaemic heart disease. Fifty-four patients with LV dysfunction (mean ejection fraction (EF) 35?±?8%) scheduled to undergo myocardial revascularization underwent DE-CMR and SPECT. Cine CMR was performed at baseline and at 8?months follow-up for assessment of regional and global myocardial function. Myocardial viability was determined by the segmental extent of delayed enhancement for DE-CMR, and by quantitative analysis of tracer uptake for SPECT, and was correlated to functional recovery after revascularization. After revascularization, 172 (49%) of 350 dysfunctional segments improved at follow-up cine CMR. Sensitivity and specificity for the prediction of functional recovery was 92 and 88%, respectively, for DE-CMR as compared to 86% (P?=?0.4) and 56% (P?=?0.001) for SPECT. Global LV function showed an increase of EF?>?5% in 22 (41%) patients. The DE-CMR derived viability ratio (dysfunctional but viable myocardium) of 0.46 (sensitivity 91%, specificity 91%) was identified as predictor of increase in EF?>?5% (P?=?0.02), whereas the corresponding SPECT parameters were not predictive. DE-CMR compares favorably to SPECT for the prediction of regional and global improvement in LV function in the setting of chronic myocardial ischemia.     

Long-term prognostic value of stress-redistribution-reinjection Tl-201 imaging in patients with severe left ventricular dysfunction and coronary artery bypass surgery

Objectives: This study sought to evaluate the long-term prognostic significance of stress–redistribution–reinjection Tl-201 imaging in patients with severe left ventricular (LV) dysfunction and coronary artery bypass surgery. Background: Preoperative stress–redistribution–reinjection Tl-201 imaging detects viable but asynergic segments which show functional improvement postoperatively and is considered as a valuable noninvasive method in selection of patients with severe LV dysfunction for revascularization. The long-term prognostic value of the reinjection technique remains unclear. Methods: Fifty-two patients with severe LV dysfunction (mean ejection fraction (EF) 0.32 ± 0.03) who underwent coronary artery bypass surgery in 1993–1994 were included in the study. Patients had follow-up 49 ± 12 months. LV function was assessed by two-dimensional echocardiography. Perfusion was assessed by Tl-201 SPECT imaging and was graded on a four-point scale (0 = normal, 3 = absent uptake) using the 20 segment model. Perfusion index was derived by adding the score of all segments and dividing these by 20. Patients were divided into two groups. Group A comprised patients with seven and more dysfunctional viable myocardial segments. Group B included patients with less than seven dysfunctional but viable segments. Results: Mean EF increased from 0.32 ± 0.03 to 0.46 ± 0.04. Mean perfusion index did not show a significant difference as a whole during follow-up compared to the early postoperative values (0.9 ± 0.4 and 1.1 ± 0.4, p = NS). When adequacy of revascularization was considered, the predictive value of a positive preoperative viability test for functional improvement was 82%. Nineteen cardiac events occurred in group B patients and six in group A patients: six deaths (four from cardiac and two from noncardiac causes), 13 myocardial infarctions (MI). Multivariate Cox survival analysis identified the number of viable segments detected preoperatively (² = 7.2, p = 0.002), postoperative improvement in Tl-uptake (² = 6.6, p = 0.01) and functional improvement (² = 5.3, p = 0.03) postoperatively as independent predictors of cardiac events. Preoperative EF and functional capacity were not associated with cardiac events in long-term prognosis. Conclusion: These data suggest that preoperative stress–redistribution–reinjection Tl-201 imaging, specifically the number of viable segments detected preoperatively and postoperative improvement in Tl-201 uptake provide important long-term prognostic information in patients with severe LV dysfunction who had coronary artery bypass surgery.     

Accuracy of biphasic response, sustained improvement and worsening during dobutamine echocardiography in predicting recovery of resting myocardial dysfunction after revascularization: comparison with thallium-201 SPECT

To evaluate the accuracy of various types of wall motion response during dobutamine echocardiography (DE) in predicting functional recovery after revascularization, we studied 30 patients with stable coronary disease and left ventricular dysfunction by simultaneous DE and (201)Tl reinjection SPECT. Among 480 segments (16 segments/patient), 199 had abnormal wall motion at baseline and 167 were revascularized. The predictive value for recovery of function was 72% for a biphasic response, 61% for sustained improvement, 77% for worsening, and 27% for no change (p < 0.01 vs. each). Biphasic response had a sensitivity of 40% and specificity of 85%. Combining biphasic, sustained improvement and worsening responses, the sensitivity, specificity and accuracy were 76%, 65% and 71%, respectively. For (201)Tl SPECT, they were 90%, 65% and 78%, respectively. Thus, a biphasic response alone is of low sensitivity. Combination of biphasic, sustained improvement and worsening responses gives an accuracy rate comparable to that of (201)Tl reinjection SPECT in assessing functional recovery.     

Comparison of thallium-201 exercise SPECT and dobutamine stress echocardiography for diagnosis of coronary artery disease in patients with left bundle branch block

The present study assessed and compared the diagnostic accuracy of thallium-201 (Tl-201) exercise myocardial single photon emission computerised tomography (SPECT) and dobutamine stress echocardiography (DSE) for detection of coronary artery disease (CAD) in patients with left bundle branch block (LBBB). Study population consisted of 26 consecutive patients with permanent LBBB who were suffering from chest pain. Patients (8 women, 18 men mean age = 57 ± 8 years) were studied with DSE, Tl-201 SPECT and coronary angiography (CAG). Three different approaches for diagnosis of CAD were used to identify CAD in left arterial descending (LAD) coronary artery territories in scintigraphic studies: (1) Approach A (conventional approach): involvement of septal, and/or anterior, and/or apical wall. (2) Approach B: involvement of anterior and septal wall irrespective of apical wall. (3) Approach C: involvement of septum, anterior and apical wall. DSE gave a sensitivity of 91%, specificity of 92% and accuracy of 92% for diagnosis of CAD in the LAD coronary artery territory. Tl-201 SPECT (conventional approach) gave a sensitivity of 100%, specificity of 42% and diagnostic accuracy of 69% for diagnosis of CAD in the LAD coronary artery territory. Sensitivity, specificity and diagnostic accuracy of approach C were 33, 85 and 57% respectively. The specificity of Tl-201 SPECT significantly increased in approach C when compared with approach A and B (p < 0.02). However sensitivity of the Tl-201 SPECT with approach C showed significant decrease when compared with DSE and approach A and B (p < 0.005). Specificity of DSE for diagnosis of CAD in LAD were significantly higher than those of Tl-201 SPECT regarding the approach A and B (p < 0.01). In conclusion the use of DSE for diagnosis of CAD in patients with LBBB seems to be more suitable than Tl-201 SPECT.     

Increased myocardial wall thickening as index of viability assessment: a preliminary report on delayed contrast MRI

Purpose : Regional wall thickening measurement by delayed contrast MRI may assess myocardial viability and functional recovery of ischemic cardiomyopathy. Materials and methods : Delayed contrast MRI data was used in 40 patients with significant coronary artery disease and severe left ventricular dysfunction. Regional wall thickening on follow‐up MRI served as an index of functional recovery in patients receiving revascularization. For comparison, myocardial viability was assessed by MRI and ²⁰¹Tl SPECT in 10 patients using a 17‐segment method. Results : On 480 segments, MRI hyperintensities showed positive correlation with ²⁰¹Tl reduction (r = 0.71, p < 0.0001) in the inferior wall and apex. Delayed MRI detected myocardial viability better than ²⁰¹Tl SPECT. Delayed contrast‐enhanced MRI showed diagnostic accuracy 65%, sensitivity 95%, specificity 25%, positive predictive value 65% and negative predictive value 75%, whereas ²⁰¹Tl SPECT showed diagnostic accuracy 54%, sensitivity 72%, specificity 25%, positive predictive value 52% and negative predictive value 54%. Areas under the ROC curves by MRI and ²⁰¹Tl SPECT were 0.59 ± 0.04, 0.52 ± 0.05, respectively (p = 0.07). The viability concordance was 80% between ²⁰¹Tl SPECT and MRI. Conclusion : Delayed contrast‐enhanced MRI may detect the inferior wall thickening and apex as an index of viable myocardium better than ²⁰¹Tl SPECT. Myocardial viability may predict functional recovery after revascularization in ischemic cardiomyopathy. Copyright © 2009 John Wiley & Sons, Ltd.     

MRI检测活性心肌及其与冠状动脉造影、SPECT和PET对比研究

目的：分析MRI对冠心病患者心肌活性的诊断价值并与冠状动脉造影、SPECT和PET结果对比。方法：应用MRI对21例临床符合冠心病的患者进行检查，并将结果与冠状动脉造影、SPECT和PET检查结果对照。结果：MRI静息心肌灌注扫描检出的缺血节段比狭窄冠状动脉的供血节段少但无统计学差异（Z=-1.732，P=0．083）；比SPECT心肌灌注扫描检出的缺血节段多且有统计学差异（Z=-3．691，P=0．000）。SPECT心肌灌注扫描检出的缺血节段比狭窄冠状动脉的供血节段少且有统计学差异（Z=-3．029，P=0．002）。以正电子发射断层显像（PET）结果为标准，MR延迟扫描检测活性心肌的灵敏度为97．6％，特异度为98．4％，总符合率为98．2%，Kappa值为0．953。MR延迟扫描检出的活性心肌比PET检出的少但无统计学差异（Z=-0．209，P=0．835）。结论：MR心脏检查清晰显示心肌梗死的位置、程度和附壁血栓情况，并可对左室室壁运动进行直观显示。常规SPECT心肌灌注显像由于空间分辨率低明显低估心肌缺血范围。心肌PET显像空间分辨率低，无法显示心肌梗死的透壁程度，且不能直观显示室壁运动情况。     

Revascularization of residual viable myocardium improves left ventricular dysfunction in patients after myocardial infarction.

The symptoms and prognosis of patients after myocardial infarction are essentially influenced by left ventricular function. About 50% of infarct related segments contain partly viable myocardium. The aim of this study was to test the hypothesis that regional and global left ventricular function can be improved by revascularization of infarct related segments with residual myocardial viability. In 15 of 30 consecutive patients, residual viable myocardium was found in the affected segment within 2.2 +/- 1.6 months after AMI. Myocardial viability was estimated by exercise-redistribution-reinjection thallium scintigraphy (SPECT imaging). Rest and exercise radionuclide ventriculography was performed to measure regional and global left ventricular ejection fraction before and after revascularization of the infarct related artery. 10 +/- 3 months after revascularization we observed a significant increase in the regional left ventricular ejection fraction at rest (from 32 +/- 16% to 41 +/- 19%; p = 0.03), global left ventricular ejection fraction at rest (from 38 +/- 12% to 46 +/- 11%; p = 0.01), regional LV ejection fraction during exercise (from 34 +/- 16% to 46 +/- 20%; p = 0.01), and global left ventricular ejection fraction during exercise (from 38 +/- 14% to 49 +/- 14%; p = 0.02). The results show that after revascularization of infarct related segments with residual myocardial viability, the regional and global left ventricular ejection fraction may be significantly improved, both at rest and during exercise. Thus infarct related segments should be tested for residual viability. In its presence revascularization is recommended, as the left ventricular function may be markedly improved.     

Combined dipyridamole and dobutamine echocardiography in myocardial hibernation: comparison with thallium uptake in patients after percutaneous transluminal coronary revascularization under circulatory support.

OBJECTIVE: To investigate the specificity and sensitivity of the combination of dipyridamole and dobutamine echocardiography for predicting functional recovery in patients with reduced ventricular function after coronary angioplasty. METHODS: Twenty-five patients, mean (SD) age 60.8 (10) years, with previous myocardial infarction (> 3 months), angiographically assessed coronary artery disease, and resting regional dysfunction (left ventricular ejection fraction < 35%) were studied. They underwent rest-redistribution thallium Tl-201 single photon emission computed tomography, and low-dose pharmacologic stress echocardiography with dobutamine (up to 10 microg/kg per minute), ultra low-dose dipyridamole (0.28 mg/kg over 4 minutes), and combined dipyridamole-dobutamine administration. RESULTS: The rate of agreement between Tl-201 and stress echo was 59% for dipyridamole, 62% for dobutamine, and 71% for combined dipyridamole-dobutamine (P <.05 vs dipyridamole and vs dobutamine). Combined dipyridamole-dobutamine showed a higher sensitivity (89%) than Tl-201, dobutamine, or dipyridamole (84%, 78%, and 80%). Specificity was lower for functional recovery prediction with Tl-201 (60%) compared with dobutamine (89%), dipyridamole (90%), and combined dipyridamole-dobutamine (91%). CONCLUSION: Thallium is more sensitive than dipyridamole or dobutamine; the sensitivity gap is filled with combined dipyridamole-dobutamine. Pharmacologic stress echocardiography is more specific than Tl-201 scintigraphy.     

Prediction of long-term reverse left ventricular remodeling after revascularization or medical treatment in patients with ischemic cardiomyopathy: a comparative study between SPECT and MRI

Patients with ischemic heart disease and depressed left ventricular (LV) ejection fraction (LVEF) develop varying degrees of LV remodeling after cardiac surgical revascularization. Fifty-three patients with stable ischemic heart disease and impaired LV function (LVEF 34.9 ± 4%) were prospectively followed up for 24 months. Thirty-seven patients underwent coronary artery bypass grafting (CABG), 16 patients were treated conservatively. Cardiac magnetic resonance imaging (MRI) and SPECT were performed at baseline and after 12 and 24 months of follow-up. The patients were divided into responders and non-responders depending on the degree of LVEF improvement at 24 months follow-up (>5%—responders). MRI with ≤5 segments with DE/wall thickness ratio (DEWTR) ≥50% predicted LV reverse remodeling with a sensitivity of 86% and a specificity of 75% (AUC 0.81). An MRI finding of ≤2 segments with the DEWTR ≥75% had a corresponding sensitivity of 71% and specificity of 67% (AUC 0.75) while fixed perfusion defect on SPECT < 16.5% of LV predicted reverse remodeling with a sensitivity of 64% and a specificity of 69% (AUC 0.64). A preoperative number of segments with the DE/wall thickness ratio of ≥50 and ≥75% obtained by MRI, was found to be a better predictor of left ventricular reverse remodeling than fixed perfusion defect by SPECT. No other MRI or SPECT parameter predicted LVEF improvement at 24 months after CABG.     

Dobutamine stress-redisstribution-reinjection versus rest-redistribution thallium-201 spect in the assessment of myocardial viability

The aim of this study was to evaluate the value of thallium-201 chloride (²⁰¹Tl) reinjection imaging following dobutamine stress (DRi) to identify viable myocardium in comparison with a rest-redistribution ²⁰¹Tl protocol (RR). The identification of viable myocardium bears important consequences for adequate selection of patients with poor left ventricular function, often unable to exercise, who are considered for revascularization. Twenty-six patients with chronic coronary artery disease and depressed left ventricular function (ejection fraction 36±10%) were studied by both DRi and RR single photon emission computed tomography (SPECT). Semi-quantitative analysis of regional ²⁰¹Tl activity (5-point score) and wall motion by echocardiography using a 16-segment model was performed. Regions were classified as viable (normal/reversible/fixed moderate defects) or non-viable (fixed severe defects) and related to regional wall motion. Target heart rate was reached in 25 patients. Myocardial viability was demonstrated in 353/416 (85%) by DRi SPECT and in 346/416 (83%) by RR SPECT. The agreement between the 2 protocols was 98% with a K-value of 0.94; similar results were obtained when the analysis was limited to dyscontractile segments. In conclusion, this study demonstrates the feasibility and diagnostic value of DRi SPECT to identify viable myocardium.     

经静脉实时心肌造影超声心动图评估心肌梗死后存活心肌

目的探讨经静脉实时心肌造影超声心动图（RT-MCE）评估心肌梗死后存活心肌。方法18例准备进行血运重建术心肌梗死患者,于术前1-5天行RT-MCE检查,并于术后3个月再次行常规超声心动图检查,室壁运动分析采用18节段分析法,分为运动正常、运动减弱、无运动和反常运动。心肌存活定义为术后超声检查室壁运动明显改善。将造影结果分为3种情况：充盈缺损,造影剂充盈延迟、回声稀疏不均匀或心内膜下充盈缺损,回声均匀性增强。其中后两种情况定义为存活心肌。结果在18例心肌梗死患者中共检出109个室壁运动异常节段,运动减弱为47个,无运动为56个,反常运动为6个。注射造影剂后回声均匀性增强的心肌节段中有2个节段术前室壁运动减弱,术后运动均改善;回声不均匀或心内膜下充盈缺损的心肌节段中术前室壁运动减弱有24个节段,术后运动改善14个,术前室壁无运动有24个节段,术后运动改善20个;充盈缺损的心肌节段中术前室壁运动减弱有21个节段,术后运动均未改善,术前室壁无运动32个,术后运动改善2个。RT-MCE检出存活心肌的敏感性、特异性分别为94.7%、78.9%。结论RT-MCE能比较准确的判断心肌梗死后心肌的存活性。     

超声斑点追踪技术结合小剂量多巴酚丁胺负荷试验评价经皮冠状动脉介入治疗效果

目的利用超声斑点追踪成像(STE)技术结合小剂量多巴酚丁胺负荷(DSE)试验预测经皮冠状动脉介入治疗的效果。方法对40例缺血性心脏病患者,于冠状动脉介入治疗(PCI)术前分析其运动异常心肌节段静息与DSE条件下收缩期峰值应变率(SRs)变化。PCI术后9个月复查心脏超声,以室壁运动分数改善作为判断心肌存活的标准。结果 PCI前225个运动异常心肌节段中,术后101个节段室壁运动明显恢复(44.89%),判定为存活心肌,124个节段运动无明显改善(55.11%)。单独应用DSE准确预测72个节段为存活心肌[敏感度71.29%(72/101)],87个节段未恢复心肌[特异度70.16%(87/124)]。STE静息状态下ROC曲线下面积为0.76;SRs截断点-0.49,敏感度71.30%,特异度70.20%;结合DSE后ROC曲线下面积为0.89,SRs截断点-0.75,敏感度89.10%,特异度90.30%。无论静息还是DSE条件下存活心肌SRs均显著大于未恢复心肌(P<0.01)。结论STE与DSE相结合可显著提高预测存活心肌的准确性。潜在的有功能的存活心肌可作为筛选PCI适应证和预测PCI疗效的可靠指标。     

多巴芬酊胺超声心动图与心肌缺血

与冠脉造影及铊－２０１心肌ＳＰＥＣＴ显像对照研究疑冠心病患者２３例，评估多巴芬酊胺超声心动图在心肌缺血中的应用价值。结果表明多巴芬酊胺超声心动图检测冠脉狭窄及缺血后存活心肌的敏感度、特异度及符合率分别为７３％，７６％；７２％，８８％及７２％，８３％。评估左前降支供血节段缺血及缺血后存活心肌的能力较左旋支和右冠脉支供血节段强。     

Milrinone echocardiographic viability test: a pilot study.

We assessed the utility of milrinone to predict recovery of function after surgical myocardial revascularization in patients with severe baseline left ventricular systolic dysfunction caused by coronary artery disease (CAD). Prediction of viable myocardial segments that will regain function after revascularization may help in the selection of patients who will benefit from coronary artery bypass graft surgery (CABG) as well as aid in the choice of target sites for coronary revascularization. We investigated 20 consecutive patients with CAD and left ventricular ejection fraction < or = 40% who had evidence of myocardial viability by either thallium scan or dobutamine viability test and were candidates for elective CABG. Left ventricular regional wall motion and global ejection fraction were assessed by transesophageal echocardiography in the operating room. Measurements were done before and 10 minutes after milrinone infusion, and immediately after CABG. Left ventricular wall motion score was derived by means of a 12-segment model. Functional improvement for each segment was defined as a wall motion change > 1. Baseline ejection fraction was 27% +/- 5% (mean +/- SD). Ejection fraction increased to 35% +/- 5% after milrinone infusion (P < .0001) and to 36% +/- 6% after CABG (P < .0001). Post-CABG ejection fraction was significantly correlated with postmilrinone ejection fraction (r = 0.65, P < .0001). Milrinone infusion resulted in augmentation of contraction in 98 of the 209 abnormal segments (wall motion score > or = 2); 91 (92.9%) of these improved after CABG. One hundred nine of the 111 segments that showed no improvement with milrinone did not improve after revascularization (98.2%). Seventy-three segments were akinetic or dyskinetic at baseline; 46 (63.0%) of these improved with milrinone. Improvement in regional wall motion after revascularization was detected in 84.8% of the segments that improved with milrinone versus only 3.7% of the segments that did not improve with milrinone. In patients with ischemic cardiomyopathy, improvement in left ventricular function (segmental wall motion and global ejection fraction) during milrinone infusion is highly predictive of improvement after CABG.     

Evaluation of immediate post-stress wall motion on adenosine stress/rest Thallium-201 Gated Myocardial SPECT

As early as 10 min after adenosine stress, immediate post-stress wall motion can be evaluated on adenosine stress/rest Tl-201 gated myocardial SPECT. To widen the applications of Tl-201 in gated SPECT, we investigated the reproducibility of LV parameters (EF, EDV, and ESV), and the diagnostic competency of immediate post-stress wall motion evaluations obtained by adenosine stress/rest Tl-201 gated myocardial SPECT. Myocardial perfusion and wall motion were evaluated using a 5-point scoring system in 20-segment model using Cedas automatic gated software (AutoQUANT 4.3.1). The reproducibilities of LV parameters were examined through repeated acquisition (n=31). Diagnostic competency was evaluated vs. coronary angiography, and multivariate logistic regression analysis was used to determine whether stress abnormal perfusion (SSSp), stress abnormal wall motion (SSSwm), or reversible abnormal wall motion (SDSwm) predict coronary stenosis (> 70%) (n=60). Two standard deviations for immediate post-stress wall motion were smaller than those for rest at EF (8.6 vs. 10.7%) and ESV (6.0 ml vs 8.4 ml). Univariate logistic regression analysis identified SSSp (p=0.006), SSSwm (p=0.016), and SDSwm (p=0.020) are significant predictors, but only SSSp (p=0.013) and SDSwm (p=0.039) were found to be significant by multivariate analysis. In addition, SSSwm or SDSwm were able to find undetected coronary artery disease in 54.5% (6/11) of patients with normal perfusion. We conclude that Tl-201 can be successfully applied to gated SPECT for immediate post-stress wall motion evaluation, and that reversible wall motion abnormality on adenosine stress/rest Tl-201 gated myocardial SPECT is an independent predictor of significant coronary artery disease.