Assessment of the left atrial myxoma with gated blood pool SPECT

A left atrial myxoma with 4 cm diameter was studied with ECG gated Tc-99m blood pool SPECT. The long axial images showed the myxoma to protrude through the mitral valve (MV) during diastole and to come back into the atrium in systole. No significant atrial dilatation due to the MV obstruction was detected. The ejection fraction calculated from the SPECT images was 10% lower than that of the conventional method viewed from LAO 45 degrees. Nuclear medicine gave an additional information for the assessment of the hemodynamics.     

SPECT versus planar gated blood pool imaging for left ventricular evaluation

Background  We developed a new segmentation algorithm based on the invariance of the laplacian (IL) to compute volumes and ejection fractions and compared these results with planar analysis and gradients by use of a standard algorithm (QBS). Methods and Results  Planar and single photon emission computed tomography blood pool acquisition was performed in 202 patients. Planar left ventricular ejection fraction (LVEF) was used as the gold standard, and single photon emission computed tomography images were processed by both 3-dimensional (3D) methods. Correlations between each 3D algorithm and planar methodology were as follows:r=0.77 for QBS andr=0.84 for IL. Mean LVEFs were 32.72%±13.05% for the planar method, 32.32%±15.98% for QBS, and 31.93%±13.44% for IL (P=.16). Bland-Altman analysis closely demonstrated negligible systematic bias for both 3D methods. Standard errors of bias were comparable between methods (9.36% for QBS and 7.44% for IL,P=.48). Linear regression of the Bland-Altman bias revealed a slope significantly different from 0 for the QBS method (0.22±0.048,P<.0001) but not for IL (−0.032±0.0044,P=.47). Conclusion  The new segmentation algorithm provides comparable results to QBS and planar analysis. However, with QBS, the difference in LVEF was correlated with the magnitude of LVEF, which was not found with the new algorithm.     

Automatic quantification of right ventricular function with gated blood pool SPECT

BACKGROUND: Quantification of right ventricular (RV) function is clinically relevant for the risk stratification and follow-up of patients with a wide spectrum of disease. This can be achieved with electrocardiography-gated blood pool single photon emission computed tomography (GBPS). We aimed to evaluate the accuracy of the completely automatic QBS GBPS processing software as compared with equilibrium planar radionuclide angiography (RNA) and with a GBPS manual segmentation method (GBPS(35%)) for the measurement of global RV ejection fraction (EF), taking the first-pass RNA (FP-RNA) as the gold standard. In parallel, we compared the RVEF, RV end-diastolic volume (EDV), and RV end-systolic volume (ESV) provided by QBS and GBPS(35%). METHODS AND RESULTS: The population included 85 patients with chronic post-embolic pulmonary hypertension. Twenty-one patients were excluded because of unsuccessful FP-RNA. Intraobserver and interobserver RVEF, RVEDV, and RVESV reproducibilities encountered with planar RNA, QBS, and GBPS(35%) were similar and compared favorably with those calculated with FP-RNA for RVEF. Mean RVEF was different between all methods. RVEF calculated with FP-RNA was better correlated to QBS (r = 0.68) and GBPS(35%) (r = 0.70) than to planar RNA (r = 0.59). RVEDV and RVESV with QBS were lower than with GBPS(35%), by 29% +/- 14% and 36% +/- 13%, respectively. RVEDV and RVESV with QBS were highly correlated to corresponding GBPS(35%) values: r = 0.88 and r = 0.91, respectively. CONCLUSION: As opposed to FP-RNA, GBPS is highly successful for the quantification of RV function. Both QBS and GBPS(35%) provide RVEF values similarly well correlated to FP-RNA and performed better than planar RNA. RVEF, RVEDV, and RVESV provided by QBS and GBPS(35%) are highly correlated. All of these RV functional measurements require further validation versus a better gold standard before their accuracy can be established.     

Assessment of an intermediate reprojection technique transitioning from planar to SPECT radionuclide ventriculography

Background

The technique of SPECT-RNV (radionuclide ventriculography) offers a greater amount of clinically usable data than its planar counterpart (P-RNV). In transitioning from planar to SPECT-only acquisition methodologies, reprojection of the SPECT data can provide a planar dataset which can be used as an interim technique. The aim of this study was to test if reprojected planar images could be used as a surrogate for true planar images in SPECT-only setting.

Methods

We performed SPECT-RNV and P-RNV on 47 patients on traditional sodium iodide (NaI) cameras, determining left ventricular ejection fractions (LVEF) for planar (EF_P) and SPECT (EF_S) techniques. We reprojected the SPECT-RNV data along the best septal separation angle determined from planar scanning. This creates a further planar dataset denoted ‘reprojected P-RNV’ (rP-RNV) giving a reprojected ejection fraction (EF_R) which can be used as a validation variable in transitioning to SPECT-only acquisition.

Results

Performing t tests showed no statistical difference between EF_P and EF_R (P > .017) but bias was observed in EF_S results compared to EF_P and EF_S compared to EF_R results. An unblinded, comparison of parametric data between the three datasets for a subset of ten patients showed good clinical concordance. False negative and false positive rates were low for rP-RNV compared to P-RNV.

Conclusions

The reprojected planar LVEF correlates well to P-RNV EF values. The rP-RNV dataset can aid clinicians in transitioning from planar RNV to SPECT-only acquisition.     

Model dependence of gated blood pool SPECT ventricular function measurements

BACKGROUND: Calculation differences between various gated blood pool (GBP) single photon emission computed tomography (SPECT) (GBPS) algorithms may arise as a result of different modeling assumptions. Little information has been available thus far regarding differences for right ventricular (RV) function calculations, for which GBPS may be uniquely well suited. METHODS AND RESULTS: Measurements of QBS (Cedars-Sinai Medical Center, Los Angeles, Calif) and BP-SPECT (Columbia University, New York, NY) algorithms were evaluated. QBS and BP-SPECT left ventricular (LV) ejection fraction (EF) correlated strongly with conventional planar-GBP LVEF for 422 patients (r = 0.81 vs r = 0.83). QBS correlated significantly more strongly with BP-SPECT for LVEF than for RVEF (r = 0.80 vs r = 0.41). Both algorithms demonstrated significant gender differences for 31 normal subjects. BP-SPECT normal LVEF (67% +/- 9%) was significantly closer to values in the magnetic resonance imaging (MRI) literature (68% +/- 5%) than QBS (58% +/- 9%), but both algorithms underestimated normal RVEF (52% +/- 7% and 50% +/- 9%) compared with the MRI literature (64% +/- 9%). For 21 patients, QBS correlated similarly to MRI as BP-SPECT for LVEF (r = 0.80 vs r = 0.85) but RVEF correlation was significantly weaker (r = 0.47 vs r = 0.81). For 16 dynamic phantom simulations, QBS LVEF correlated similarly to BP-SPECT (r = 0.81 vs r = 0.91) but QBS RVEF correlation was significantly weaker (r = 0.62 vs r = 0.82). Volumes were lower by QBS than BP-SPECT for all data types. CONCLUSIONS: Both algorithms produced LV parameters that correlated strongly with all forms of image data, but all QBS RV relationships were significantly different from BP-SPECT RV relationships. Differences between the two algorithms were attributed to differences in their underlying ventricular modeling assumptions.     

Comparison of radionuclide ventriculography using SPECT and planar techniques in different cardiac conditions

PURPOSE: Accurate assessment of ventricular function is required to optimize therapeutic management of cardiac diseases. The aim of this study was to correlate planar equilibrium multigated acquisition (MUGA) with tomographic ventriculography (SPECT) in patients with diverse volumes and wall motion abnormalities. METHODS: Eighty-three studies in 80 patients (56+/-14 years; 56% women) were classified according to ventricular dilation, wall motion abnormalities and systolic dysfunction. Left and right ventricular ejection fraction (LVEF and RVEF) and end-diastolic and end-systolic left ventricular volumes (EDV and ESV) were obtained using a commercial QBS program for SPECT. On planar acquisition, LVEF and RVEF were obtained using standard techniques and volumes were determined using the count-based method, without blood sampling. RESULTS: A. Total group: With the planar method, LVEF was 44+/-17%, RVEF 42+/-13%, left EDV 147+/-97 ml (range 31-487 ml) and left ESV 93+/-85 ml (range 15-423 ml); with SPECT the corresponding values were 40+/-20%, 49+/-16%,131+/-95 ml and 91+/-89 ml, respectively (p=NS for all but RVEF). Linear correlation was 0.845 for LVEF, 0.688 for RVEF, 0.927 for left EDV and 0.94 for left ESV, with good intra-class correlation. B. Subgroups: Global and intra-class correlations between planar imaging and SPECT were high for volumes, RVEF and LVEF in all subgroups, except in patients with normal wall motion and function, who showed smaller volumes with SPECT. The group with diffuse wall motion abnormalities had a lower EDV on SPECT. In the abnormal left ventricle, RVEF was higher with SPECT. CONCLUSION: Good correlation and agreement exist between SPECT and planar MUGA with respect to LVEF and left ventricular volumes. SPECT is useful in patients with functional abnormalities, but less reliable in those with normal small cavities. A combined technique is still necessary, and RVEF should be interpreted cautiously.     

Comparison of biventricular ejection fractions using cadmium-zinc-telluride SPECT and planar equilibrium radionuclide angiography

Background

We compared biventricular ejection fractions (EFs) from gated blood-pool single-photon emission computed tomography (SPECT) using a cadmium-zinc-telluride camera (CZT-SPECT) with planar equilibrium radionuclide angiography (ERNA) using a NaI gamma camera (NaI-planar). We also evaluated whether imaging time can be reduced without compromising image quality using the CZT camera.

Methods

Forty-eight patients underwent NaI-planar and CZT-SPECT on the same day. CZT-SPECT datasets were re-projected at an LAO orientation similar to ERNA acquisition, forming CZT-repro planar datasets. The resulting biventricular volumetric measurements and EFs were compared.

Results

LVEF calculated from CZT-SPECT and CZT-repro correlated better with NaI-planar (r = 0.93 and 0.99, respectively) than RVEF (r = 0.76 and 0.82, respectively). Excellent intra-class correlation and low bias in intra-observer comparisons were observed for the biventricular EFs derived from three datasets. A wider limit of agreement in CZT-SPECT-derived LVEFs, lower correlation and significant bias for NaI-planar, and CZT-repro-derived RVEFs was found in the inter-observer analyses. Nonetheless, the imaging time can be reduced to 4 minutes without increasing variability in EFs using the CZT camera (P = NS).

Conclusions

LVEFs calculated from CZT-SPECT and CZT-repro correlated well with NaI-planar. CZT camera may reduce imaging time while preserving image quality in the assessment of biventricular EFs.

     

Automatic quantification of right ventricular volumes and right ventricular ejection fraction with gated blood pool SPECT: Comparison of 8- and 16-frame gated blood pool SPECT with first-pass radionuclide angiography

BACKGROUND: The aim of this study was to compare 8- and 16-frame gated blood pool single photon emission computed tomography (SPECT) (GBPS) for the determination of right ventricular ejection fraction (RVEF) and right ventricular (RV) volumes in subjects who underwent two consecutive GBPS studies. METHODS AND RESULTS: In this study 65 consecutive patients (29 men and 36 women) referred for first-pass radionuclide angiography (FP-RNA) underwent FP-RNA and both 8- and 16-frame GBPS. The mean FP-RNA RVEF was statistically lower than RVEF determined by 8-frame GBPS (P < .001) and 16-frame GBPS (P < .001). Comparison of RVEF by FP-RNA and GBPS yielded coefficients of 0.8666 (P < .0001) for 16-frame GBPS and 0.7290 (P < .0001) for 8-frame GBPS. The correlation of RVEF between 8- and 16-frame GBPS showed a coefficient of 0.6657 (P < .0001). The mean RV end-diastolic volume (EDV) calculated with 8- and 16-frame GBPS showed no statistical differences (P = .3580). The mean RV end-systolic volume (ESV) calculated with 8- and 16-frame GBPS also showed no statistical differences (P = .2265). Comparison of EDV by 8- and 16-frame GBPS yielded a coefficient of 0.7327 (P < .0001). The correlation between ESV by 8-frame GBPS and 16-frame GBPS showed a coefficient of 0.6067 (P < .0001). CONCLUSION: GBPS is a simple and reproducible acquisition method for the assessment of RVEF and RV volumes. RVEF values calculated by 8- and 16-frame GBPS correlated well with FP-RNA, although mean RVEF values from FP-RNA were lower than GBPS RVEF values. In addition, RV ESV and EDV were both well correlated with 8- and 16-frame GBPS. GBPS should prove to be useful in diagnosis, as well as in following disease progression and evaluating the efficacy of therapeutic interventions, in patients with biventricular dysfunction.     

Comparison of left ventricular contraction homogeneity index using SPECT gated blood pool imaging and planar phase analysis

Background  There is growing interest in developing a practical technique to accurately assess ventricular synchrony. We describe a novel 3-dimensional (3D) gated blood pool single photon emission computed tomography (SPECT) approach, from which a contraction homogeneity index (CHI) is derived and compared with planar phase analyses. Methods and Results  Subjects underwent planar and SPECT blood pool acquisition. Planar images were processed for left ventricular ejection fraction computation and phase values. SPECT images were processed by our novel algorithm, with which CHI was computed. Overall, 235 patients (79% male; mean age, 62±11 years) completed the study. Left ventricular ejection fractions were similar by planar (33.5%±13.5%) and 3D (34.7%±12.7%) methods (r=0.83, P<.0001). Mean phase angles for planar and tomographic methods were 126.3°±29.6° and 124.4°±28.7°, respectively (r=0.53, P<.0001). Phase and amplitude signals were incorporated in the CHI, which was non-normally distributed with a median of 73.8% (interquartile range, 58.7%–84.9%). This index minimized the negative impact of dyskinetic wall segments with limited regional motion. The planar heterogeneity index (SDΦ) was 28.2° (interquartile range, 17.5°–46.8°) and correlated inversely with CHI (r=−0.61, P<.0001). Conclusion  The novel 3D dispersion index CHI accounts for both phase delay of a dyssynchronous segment and its magnitude of contraction and is moderately correlated with planar phase analyses. Its potential in cardiac resynchronization therapy remains to be exploited. This work was supported in part by the “Fonds de la Recherche en Santé du Québec” and by a Canada Research Chair.     

Assessment of poststress left ventricular ejection fraction by gated SPECT: comparison with equilibrium radionuclide angiocardiography

Purpose

We compared left ventricular (LV) ejection fraction obtained by gated SPECT with that obtained by equilibrium radionuclide angiocardiography in a large cohort of patients.

Methods

Within 1 week, 514 subjects with suspected or known coronary artery disease underwent same-day stress–rest ^99mTc-sestamibi gated SPECT and radionuclide angiocardiography. For both studies, data were acquired 30 min after completion of exercise and after 3 h rest.

Results

In the overall study population, a good correlation between ejection fraction measured by gated SPECT and by radionuclide angiocardiography was observed at rest (r=0.82, p<0.0001) and after stress (r=0.83, p<0.0001). In Bland-Altman analysis, the mean differences in ejection fraction (radionuclide angiocardiography minus gated SPECT) were ?0.6% at rest and 1.7% after stress. In subjects with normal perfusion (n=362), a good correlation between ejection fraction measured by gated SPECT and by radionuclide angiocardiography was observed at rest (r=0.72, p<0.0001) and after stress (r=0.70, p<0.0001) and the mean differences in ejection fraction were ?0.9% at rest and 1.4% after stress. Also in patients with abnormal perfusion (n=152), a good correlation between the two techniques was observed both at rest (r=0.89, p<0.0001) and after stress (r=0.90, p<0.0001) and the mean differences in ejection fraction were 0.1% at rest and 2.5% after stress.

Conclusion

In a large study population, a good agreement was observed in the evaluation of LV ejection fraction between gated SPECT and radionuclide angiocardiography. However, in patients with perfusion abnormalities, a slight underestimation in poststress LV ejection fraction was observed using gated SPECT as compared to equilibrium radionuclide angiocardiography.     

Determination of right ventricular ejection fraction from reprojected gated blood pool SPET: comparison with first-pass ventriculography

Gated blood pool (GBP) studies are widely available and relatively inexpensive. We have previously published a simple and convenient method for measuring left ventricle ejection fraction (EF) with increased accuracy from single-photon emission tomography (SPET) GBP scans. This paper describes an extension of this method by which right ventricular EF may also be measured. Gated SPET images of the blood pool are acquired and re-oriented in short-axis slices. Counts from the left ventricle are excluded from the short-axis slices, which are then reprojected to give horizontal long-axis images. Time-activity curves are generated from each pixel around the right ventricle, and an image is created with non-ventricular pixels "greyed out". This image is used as a guide in drawing regions of interest around the right ventricle on the end-diastolic and end-systolic long-axis images. In 28 patients, first-pass ventriculography studies were acquired followed by SPET GBP scans. The first-pass images were analysed a total of four times by two observers and the SPET images were analysed three times each by two observers. The agreement between the two techniques was good, with a correlation coefficient of 0.72 and a mean absolute difference between first-pass and reprojected SPET EFs of 4.8 EF units. Only four of the 28 patients had a difference of greater than 8 EF units. Variability was also excellent for SPET right ventricular EF values. Intra-observer variability was significantly lower for SPET than for first-pass EFs: standard error of the estimate (SEE)=5.1 and 7.3 EF units, respectively (P<0.05). Inter-observer variability was comparable in the two techniques (SEE=5.2 and 6.9 EF units for SPET and first-pass ventriculography, respectively).     

Ventricular ejection fraction in patients with dilated cardiomyopathy calculated by gated blood pool SPET processing software: correlation with multigated acquisition and first pass radionuclide ventriculography

This study was performed to find out the left ventricular ejection fraction (LVEF) and right ventricular ejection fraction (RVEF) in patients with dilated cardiomyopathy (DCM) by using commercially available automated gated blood pool scintigraphy (GBPS) processing software and to correlate it with first pass radionuclide ventriculography (FPRNV) and planar multigated acquisition (MUGA). However, till date, no literature exists studying the application of GBPS and planar radionuclide ventriculography techniques in the setting of patients with DCM as a single cohort. Forty-one patients having DCM were prospectively included in the study. First pass RNV and MUGA were performed at rest after in-vivo labeling of red blood cells in all patients. Immediately after obtaining the planar views, GBPS was performed and LVEF and RVEF were calculated. Our results showed that the %LVEF values (mean±SD) calculated by MUGA, GBPS and echo cardiography were 31±11, 34±12 and 32±11, respectively. The % RVEF values (mean±SD) calculated by FPRNV and GBPS were 46±14 and 43±17, respectively. The LVEF values calculated by MUGA, GBPS and echcardiography showed very good correlation r=0.924 and r=0.844, respectively and for both P <0.0001. Bland-Altman plot showed overestimation for LVEF (and a tendency for overestimation of RVEF) values calculated by GBPS compared to MUGA. Values of RVEF calculated by GBPS and FPRNV also showed good correlation (r=0.88; P< 0.0001). In conclusion, the automated GBPS for LVEF and RVEF calculation using GBPS SPET can be routinely applied in DCM patients. Given the practical difficulties with FPRNV like good bolus administration, quantitative blood pool SPET (QBPS) can be used to calculate RVEF. Similarly MUGA and GBPS can be used to calculate LVEF.     

Determination of right ventricular ejection fraction from reprojected gated blood pool SPET: comparison with first-pass ventriculography

Gated blood pool (GBP) studies are widely available and relatively inexpensive. We have previously published a simple and convenient method for measuring left ventricle ejection fraction (EF) with increased accuracy from single-photon emission tomography (SPET) GBP scans. This paper describes an extension of this method by which right ventricular EF may also be measured. Gated SPET images of the blood pool are acquired and re-oriented in short-axis slices. Counts from the left ventricle are excluded from the short-axis slices, which are then reprojected to give horizontal long-axis images. Time-activity curves are generated from each pixel around the right ventricle, and an image is created with non-ventricular pixels "greyed out". This image is used as a guide in drawing regions of interest around the right ventricle on the end-diastolic and end-systolic long-axis images. In 28 patients, first-pass ventriculography studies were acquired followed by SPET GBP scans. The first-pass images were analysed a total of four times by two observers and the SPET images were analysed three times each by two observers. The agreement between the two techniques was good, with a correlation coefficient of 0.72 and a mean absolute difference between first-pass and reprojected SPET EFs of 4.8 EF units. Only four of the 28 patients had a difference of greater than 8 EF units. Variability was also excellent for SPET right ventricular EF values. Intra-observer variability was significantly lower for SPET than for first-pass EFs: standard error of the estimate (SEE)=5.1 and 7.3 EF units, respectively (P<0.05). Inter-observer variability was comparable in the two techniques (SEE=5.2 and 6.9 EF units for SPET and first-pass ventriculography, respectively).     

Parametric phase display for biventricular function from gated cardiac blood pool single-photon emission tomography

Complete assessment of biventricular function from planar ECG-gated cardiac blood pool studies has been limited because of the overlap of adjacent activity-containing structures. Theoretically, single-photon emission tomography (SPET) can be used to comprehensively evaluate both ventricles by isolating them from surrounding anatomy. However, an enormous amount of parametric data is generated from gated SPET studies, and much of it is diagnostically irrelevant for ventricular wall motion analysis. To compress this information to a more easily interpretable format, a two-dimensional parametric display has been developed. Fourier analysis of short-axis tomograms from a gated cardiac blood pool SPET study generates three-dimensional, first-harmonic phase data. Circumferential profile data from the parametric tomograms of the right and left ventricle are mapped onto a two-dimensional polar display. This method is demonstrated in a normal patient and in three patients with abnormal ventricular contraction patterns and appears to have potential application for the analysis and characterization of biventricular wall motion. Correspondence to: D.R. Neumann     

Assessment of left ventricular ejection fraction by four different methods using 99mTc tetrofosmin gated SPECT in patients with small hearts: correlation with gated blood pool

AIM: To compare the currently available gated SPECT software programs, quantitative gated SPECT (QGS), Emory Cardiac Toolbox (ECTb), Left Ventricular Global Thickening Fraction (LVGTF), and the recently developed Layer of Maximum Count (LMC) method with equilibrium Gated Blood Pool (GBP) scintigraphy in calculating the ejection fraction in patients with small hearts. METHODS: Twenty patients with small hearts (end diastolic volume <85 ml) were collected for the study. Gated myocardial perfusion SPECT and planar GBP were performed for all patients. The four methods QGS, ECTb, and LVGTF and LMC were used for volumes estimation and ejection fraction calculation. RESULTS: ANOVA analysis revealed significant differences among the methods in ejection fraction estimation (P<0.0001). The mean ejection fraction by GBP was significantly overestimated by QGS and ECTb and LVGTF (P<0.0001, P<0.0001 and P=0.006, respectively). The mean ejection fraction by GBP was not significantly different from that by the LMC method (P=0.213). Ejection fraction measurements by QGS and ECTb yielded moderate correlation with GBP values (r=0.588, P=0.006; and r=0.564, P=0.010, respectively). The ejection fraction by the LMC method was marginally correlated but LVGTF showed a non-significant correlation with GBP (r=0.438, P=0.053; and r=0.155, P=0.515, respectively). Agreement analysis for ejection fraction estimation by QGS and ECTb demonstrated a non-significant correlation between the difference and the mean. The LMC method showed a non-significant trend to decrease the difference with GBP as the mean increased. However, the LVGTF method significantly increased the difference as the mean increased. CONCLUSION: The currently available gated SPECT methods have moderate to poor correlations in addition to wide agreement limits with gated blood pool studies in patients with small hearts. Improvement of these methods to achieve better results in such patients is recommended. The newly developed LMC method yielded better results in the group with small hearts but with low interchangeability with GBP studies.     

Assessment of left ventricular diastolic function: comparison of contrast ventriculography and equilibrium radionuclide angiography.

Twenty-two patients with coronary artery disease were studied first by radionuclide angiography (RNA) and then by contrast ventriculography. Cardiac medications were discontinued at least 72 hr before study. The patients were studied during atrial pacing at heart rates close to their spontaneous sinus rhythm. Contrast ventriculography was performed at 50 frames/sec in the 30 degrees right anterior oblique projection using 40 ml of a nonionic contrast medium (iopamidol) at a flow rate of 10-12 ml/sec. The contours of the left ventricular silhouette at contrast ventriculography were traced, frame by frame, on a graphic table with a digitizing penlight. Equilibrium 99mTc RNA was performed in the best septal 45 degrees left anterior oblique projection, acquiring 150,000 cts/frame, at 50 frames/sec and with a 5% gate tolerance. Time-activity curves from both end-diastolic and end-systolic ROIs were built and interpolated. Both RNA and contrast ventriculography volume curves were filtered with Fourier five harmonics. A close relationship was found between RNA and contrast ventriculography measurements of peak filling rate normalized to end-diastolic cps (r = 0.87, p less than 0.001) and stroke count (r = 0.87, p less than 0.001), ejection fraction (r = 0.94, p less than 0.001). Thus, in patients with coronary artery disease, LV filling can be accurately assessed using RNA.     

平衡法门控核素心室显像评价生长激素对扩张型心肌病心功能的影响

目的　评价基因重组生长激素 (rhGH)对扩张型心肌病 (DCM)心功能的影响及疗效。方法　采用99Tcm RBC平衡法门控心室显像 ,将 5 6例DCM伴中、重度心力衰竭患者随机分为rhGH治疗组 (2 8例 )和对照组 (2 8例 )。rhGH组 :在常规内科治疗基础上隔日肌肉注射rhGH 4.5U ;对照组采用单纯内科常规治疗方法。疗程均为 3个月。治疗前后进行超声心动图和门控心室显像 ,观察各项心功能指标。结果　rhGH治疗 3个月后DCM患者二维超声心动图所测左室收缩末内径 (LVEsd)由用药前 (5 9.8± 7.2 )mm缩小至用药后 (5 3 .6± 8.4)mm(P <0 .0 1)。99Tcm RBC平衡法门控心室显像 :rhGH组中左室扩大为主 7例 :左室射血分数 (LVEF)由治疗前 (2 8.3 2± 6.95 ) %升至用药后 (3 8.3 0±5 91) % (P <0 .0 1) ,左室高峰射血率 (PER ,EDV/s)由治疗前 2 .11± 0 .91升至用药后 2 .96± 0 .6(P <0 .0 1) ;双心室扩大组 2 1例 :LVEF由治疗前 (2 3 .6± 9.65 ) %升至 (3 5 .65± 9.2 1) % (P <0 .0 1) ,左室PER由治疗前 0 .94± 0 .65升至 1.76± 0 .82 (P <0 .0 1) ;右室射血分数 (RVEF)由 (2 2 .40± 7.5 1) %升至(3 3 .65± 5 .11) % (P <0 .0 1) ,右室PER由 0 .89± 0 .46升至 1.3 7± 0 .5 1(P <0 .0 5 )。结论　rhGH治疗3个月后DCM患     

放射性核素心脏显像对SLE患者的临床应用

目的评价系统性红斑狼疮（ＳＬＥ）患者左心室功能。方法用平衡法门电路心室显像及心肌显像测定２０例正常人和３０例ＳＬＥ患者左室收缩和舒张功能。结果ＳＬＥ患者左室射血分数、相角程、高峰射血率、高峰充盈率分别为０５２±０１１、６０８９±１２１２°、３０８±０４８ＥＤＶ／ｓ和２８８±０４７ＥＤＶ／ｓ；正常对照组分别为０６８±００２、５３２５±５２６°、３６６±０５１ＥＤＶ／ｓ和３３４±０８８ＥＤＶ／ｓ。两组比较，ｔ值分别为４５０、３１１、５８０和４６０，Ｐ均＜００１。阳性率为４８６％，心肌显像阳性率为６４％；放射性核素心脏显像检测ＳＬＥ心肌损害的灵敏度为６３％，特异性为８５％。结论放射性核素心脏显像可以客观评价ＳＬＥ患者左心室功能，对发现ＳＬＥ心肌损害及指导治疗有一定意义。