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Ji Chen - One of the best experts on this subject based on the ideXlab platform.
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Development and Validation of a Phase Analysis Tool to Measure Interventricular Mechanical Dyssynchrony From Gated SPECT MPI
'Springer Science and Business Media LLC', 2017Co-Authors: Zhou Weihua, Ji Chen, Garcia Ernest, Jiang Zhixin, Li DianfuAbstract:Objectives: The purpose of this study is to develop a right-ventricular (RV) phase analysis tool which when coupled with our left ventricular (LV) phase analysis tool can provide measurement of the interventricular mechanical dyssynchrony from Gated SPECT myocardial perfusion imaging (MPI), and validate the tool by electrocardiography (ECG). Methods: For each patient, short-axis LV and RV SPECT MPI images were input into an automatic sampling algorithm to generate the 3D maximal count circumferential profiles for both LV and RV in each cardiac frame. Subsequently, the samples of LV and RV were separately used by our phase analysis tool based on the first-harmonic Fourier approximation to calculate the contraction onset for each sample. The difference between contraction onsets of the middle LV free wall and middle LV septal wall represented the LV contraction delay; the difference between contraction onsets of the middle RV free wall and middle RV septal wall represented the RV contraction delay. The difference between the LV and RV contraction delays represented the interventricular contraction delay, which was compared with the interventricular conduction delay classified by ECG to validate the concordance of interventricular mechanical and electrical dyssynchrony. Sixty-one bundle branch block (BBB) patients with ischemic-dilated cardiomyopathy (26, 42.6%) or non-ischemic-dilated cardiomyopathy (35, 57.4%), who underwent 12-lead surface ECG and Gated resting Tc-99m sestamibi SPECT, were retroSPECTively analyzed in this study. Results: In the 30 patients with left bundle branch block (LBBB) by ECG, there were 27 patients whose LV contracted later than the RV according to SPECT; and in the 31 patients with right bundle branch block (RBBB) by ECG, there were 26 patients whose LV contracted earlier than the RV according to SPECT. In total, an agreement rate of 86.9% (53 of 61) was achieved between SPECT and ECG. The Kappa agreement rate was 73.8% (95% confidence interval 0.57-0.91). Conclusion: The preliminary results showed promise for the measurement of interventricular mechanical dyssynchrony in BBB patients with dilated cardiomyopathy using our phase analysis tool
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relation of early post stress left ventricular dyssynchrony and the extent of angiographic coronary artery disease
Journal of Nuclear Cardiology, 2014Co-Authors: Wensheng Huang, Chingpei Chen, Guanguei Hung, Chinghui Huang, Ji ChenAbstract:Background Previous studies showed different dyssynchrony patterns between ischemic and normal myocardium at early post-stress using Tl-201 Gated SPECT myocardial perfusion imaging (MPI). The aim of this study was to assess the relation of stress-induced dyssynchrony and the extent of angiographic coronary artery disease (CAD).
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a proSPECTive pilot study to evaluate the relationship between acute change in left ventricular synchrony after cardiac resynchronization therapy and patient outcome using a single injection Gated SPECT protocol
Circulation-cardiovascular Imaging, 2011Co-Authors: Mati Friehling, Ernest V. Garcia, Ji Chen, Samir Saba, Raveen Bazaz, David Schwartzman, Evan Adelstein, William P Follansbee, Prem SomanAbstract:Background— There are ongoing efforts to optimize patient selection criteria for cardiac resynchronization therapy (CRT). In this regard, the relationship between acute change in left ventricular synchrony (LV) after CRT and patient outcome remains undefined. Methods and Results— A novel protocol was designed to evaluate acute change in left LV synchrony after CRT using phase analysis of standard Gated single-photon emission computed tomography (SPECT) myocardial perfusion imaging with a single injection of radiotracer and proSPECTively applied to 44 patients undergoing CRT. Immediately after CRT, 18 (41%), 11 (25%), and 15 (34%) patients had an improvement, no change, or a worsening in LV synchrony. An algorithm incorporating the presence of baseline dyssynchrony, myocardial scar burden, and lead concordance predicted acute improvement or no change in LV synchrony with 72% sensitivity, 93% specificity, 96% positive predictive value, and 64% negative predictive value and had 96% negative predictive value for acute deterioration in synchrony. Over a follow-up period of 9.6±6.8 months, patients who had an acute deterioration in synchrony after CRT had a higher composite event rate of death, heart failure hospitalizations, appropriate defibrillator discharges, and CRT device deactivation for worsening heart failure symptoms, compared with patients who had an improvement or no change [hazard ratio, 4.6 (1.3 to 16.0); log rank test; P =0.003]. Conclusions— In this single-center pilot study, phase analysis of Gated SPECT was successfully used to predict acute change in LV synchrony and patient outcome after CRT.
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left ventricular systolic and diastolic dyssynchrony as assessed by multi harmonic phase analysis of Gated SPECT myocardial perfusion imaging in patients with end stage renal disease and normal lvef
Journal of Nuclear Cardiology, 2011Co-Authors: Ji Chen, Andreas P Kalogeropoulos, Liudmila Verdes, Javed Butler, Ernest V. GarciaAbstract:Background The purpose of this study was to develop a multi-harmonic phase analysis method to measure diastolic dyssynchrony from conventional Gated SPECT myocardial perfusion imaging (MPI) data and to compare it with systolic dyssynchrony in normal subjects and in patients with end-stage renal disease (ESRD) and normal left-ventricular ejection fraction (LVEF).
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evaluation of left ventricular mechanical dyssynchrony as determined by phase analysis of ecg Gated SPECT myocardial perfusion imaging in patients with left ventricular dysfunction and conduction disturbances
Journal of Nuclear Cardiology, 2007Co-Authors: Mark A Trimble, Ernest V. Garcia, Ji Chen, Salvador Borgesneto, Stuart Smallheiser, Emily Honeycutt, Linda K Shaw, Robert Pagnanelli, Lindsey E Tauxe, Fabio EstevesAbstract:Background Cardiac resynchronization therapy (CRT) is approved for the treatment of patients with advanced systolic heart failure and evidence of dyssynchrony on electrocardiograms. However, a significant percentage of patients do not demonstrate improvement with CRT. Echocardiographic techniques have been used for more accurate determination of dyssynchrony. Single photon emission computed tomography (SPECT) myocardial perfusion imaging has not previously been used to evaluate cardiac dyssynchrony. The objective of this study is to evaluate mechanical dyssynchrony as described by phase analysis of Gated SPECT images in patients with left ventricular dysfunction, conduction delays, and ventricular paced rhythms.
Mario S Verani - One of the best experts on this subject based on the ideXlab platform.
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evaluation of left ventricular wall motion volumes and ejection fraction by Gated myocardial tomography with technetium 99m labeled tetrofosmin a comparison with cine magnetic resonance imaging
Journal of Nuclear Cardiology, 1999Co-Authors: Periyanan Vaduganathan, Wesley G Vick, John J Mahmarian, Mario S VeraniAbstract:Abstract Background. Whether left ventricular function can be assessed accurately by Gated single photon emission computed tomography (SPECT) in patients with myocardial infarction and severe perfusion defects is not well known. Methods and Results. Twenty-five patients with an acute myocardial infarction underwent 99mTc-labeled tetrofosmin (99mTc-tetrofosmin) Gated SPECT and cine magnetic resonance imaging (MRI). Wall motion was assessed in 13 left ventricular segments using a 5-point scoring system ranging from 3 (normal) to -1 (dyskinetic). Exact agreement for wall motion scores between Gated SPECT and MRI was excellent (92%, kappa = 0.82). Furthermore, correlations between the two techniques were also good for end-diastolic volume (r = 0.81, P Conclusion. In patients with a recent myocardial infarction, 99mTc-tetrofosmin Gated SPECT provides reliable evaluation of global and regional ventricular function and volumes.
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evaluation of left ventricular wall motion volumes and ejection fraction by Gated myocardial tomography with technetium 99m labeled tetrofosmin a comparison with cine magnetic resonance imaging
Journal of Nuclear Cardiology, 1999Co-Authors: Periyanan Vaduganathan, Wesley G Vick, John J Mahmarian, Mario S VeraniAbstract:Whether left ventricular function can be assessed accurately by Gated single photon emission computed tomography (SPECT) in patients with myocardial infarction and severe perfusion defects is not well known. Twenty-five patients with an acute myocardial infarction underwent 99mTc-labeled tetrofosmin (99mTc-tetrofosmin) Gated SPECT and cine magnetic resonance imaging (MRI). Wall motion was assessed in 13 left ventricular segments using a 5-point scoring system ranging from 3 (normal) to-1 (dyskinetic). Exact agreement for wall motion scores between Gated SPECT and MRI was excellent (92%, kappa=0.82). Furthermore, correlations between the two techniques were also good for end-diastolic volume (r=0.81, P<.0001), end-systolic volume (r=0.92, P<.0001), and ejection fraction (r=0.93, P<.0001). In patients with a recent myocardial infarction, 99mTc-tetrofosmin Gated SPECT provides reliable evaluation of global and regional ventricular function and volumes.
M Leoncini - One of the best experts on this subject based on the ideXlab platform.
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Gated single photon emission computed tomography the present day one stop shop for cardiac imaging
Quarterly Journal of Nuclear Medicine and Molecular Imaging, 2005Co-Authors: Roberto Sciagra, M LeonciniAbstract:UNLABELLED Gated single-photon emission computed tomography (SPECT) is the current state-of-the-art approach to myocardial perfusion imaging. Initially, major emphasis was given to the improvement in diagnostic accuracy of myocardial perfusion imaging for the detection of coronary artery disease, because the evaluation of wall motion and thickening allows the recognition of attenuation artifacts and increases the observer's confidence. Different processing algorithms make possible to perform a reproducible and reliable assessment of left ventricular (LV) function, which has been extensively validated against various reference METHODS Several articles report the additional value of functional data derived from Gated SPECT to increase the accuracy of myocardial perfusion imaging in particular patient groups, such as women, to enhance the detection of multivessel coronary artery disease, and to permit the recognition of severe stenosis. An extensive literature indicates that Gated SPECT allows a more accurate and reliable prognostic stratification of patients with known coronary artery disease. More recently, the peculiar contribution of Gated SPECT in the assessment of myocardial viability has been demonstrated, with the possibility to evaluate in a single myocardial perfusion study the presence of preserved tracer uptake and the amount of contractile reserve through the acquisition of Gated SPECT during inotropic stimulation with dobutamine. The most recent advance in the application of Gated SPECT is the use of this technique for the reproducible assessment of LV functional changes, at follow-up or during inotropic stimulation, with perfusion data in the background. Various clinical settings, such as assessment of response to medical or resynchronization therapy in dilated or ischemic cardiomyopathy, prediction of outcome in chronic coronary artery disease with LV remodeling, evaluation of different treatment strategies in acute myocardial infarction, could take advantage from the unique combination of perfusion and functional data made possible by the use of Gated SPECT. In conclusion, myocardial perfusion imaging with Gated SPECT is a convincing reality in the field of cardiac imaging and has a still largely unexplored potential for a wider use in heart disease.
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usefulness of distinct activity thresholds according to baseline regional asynergy for predicting functional recovery in patients with chronic coronary artery disease and left ventricular dysfunction a study with nitrate enhanced sestamibi Gated SPECT
Journal of Nuclear Cardiology, 2001Co-Authors: M Leoncini, Roberto Sciagra, Gabriella Marcucci, Fabio Frascarelli, Francesco Bellandi, Michela Gallopin, A Mennuti, R P DabizziAbstract:Background The role of Gated single photon emission computed tomography (SPECT) in improving viability detection with the use of perfusion imaging is uncertain. This study aimed to verify whether the classification of baseline regional dysfunction with Gated SPECT helps to predict functional recovery with the use of quantitative perfusion imaging.
Roberto Sciagra - One of the best experts on this subject based on the ideXlab platform.
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Gated single photon emission computed tomography the present day one stop shop for cardiac imaging
Quarterly Journal of Nuclear Medicine and Molecular Imaging, 2005Co-Authors: Roberto Sciagra, M LeonciniAbstract:UNLABELLED Gated single-photon emission computed tomography (SPECT) is the current state-of-the-art approach to myocardial perfusion imaging. Initially, major emphasis was given to the improvement in diagnostic accuracy of myocardial perfusion imaging for the detection of coronary artery disease, because the evaluation of wall motion and thickening allows the recognition of attenuation artifacts and increases the observer's confidence. Different processing algorithms make possible to perform a reproducible and reliable assessment of left ventricular (LV) function, which has been extensively validated against various reference METHODS Several articles report the additional value of functional data derived from Gated SPECT to increase the accuracy of myocardial perfusion imaging in particular patient groups, such as women, to enhance the detection of multivessel coronary artery disease, and to permit the recognition of severe stenosis. An extensive literature indicates that Gated SPECT allows a more accurate and reliable prognostic stratification of patients with known coronary artery disease. More recently, the peculiar contribution of Gated SPECT in the assessment of myocardial viability has been demonstrated, with the possibility to evaluate in a single myocardial perfusion study the presence of preserved tracer uptake and the amount of contractile reserve through the acquisition of Gated SPECT during inotropic stimulation with dobutamine. The most recent advance in the application of Gated SPECT is the use of this technique for the reproducible assessment of LV functional changes, at follow-up or during inotropic stimulation, with perfusion data in the background. Various clinical settings, such as assessment of response to medical or resynchronization therapy in dilated or ischemic cardiomyopathy, prediction of outcome in chronic coronary artery disease with LV remodeling, evaluation of different treatment strategies in acute myocardial infarction, could take advantage from the unique combination of perfusion and functional data made possible by the use of Gated SPECT. In conclusion, myocardial perfusion imaging with Gated SPECT is a convincing reality in the field of cardiac imaging and has a still largely unexplored potential for a wider use in heart disease.
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myocardial perfusion imaging using Gated SPECT in heart failure patients undergoing cardiac resynchronization therapy
The Journal of Nuclear Medicine, 2004Co-Authors: Roberto Sciagra, Marzia Giaccardi, Maria Cristina Porciani, Andrea Colella, A Michelucci, Paolo Pieragnoli, Gian Franco Gensini, Alberto Pupi, Luigi PadelettiAbstract:Cardiac resynchronization therapy (CRT) by biventricular pacing is indicated in patients with severe heart failure and left bundle branch block who remain symptomatic despite optimal medical therapy. The relationship between baseline resting perfusion pattern and hemodynamic response to CRT has not been fully investiGated. We tested the usefulness of perfusion Gated SPECT for baseline evaluation and follow-up of these patients. Methods: In 20 patients, we performed Gated SPECT before CRT and at the 3-mo follow up. Left ventricular (LV) ejection fraction (EF), end-diastolic (ED) and end-systolic (ES) volume indexes (VI), and wall motion score index (WMSI) were measured and compared with clinical outcome. Results: One patient died before follow-up. The 19 remaining patients were classified into 1 of 2 groups according to the presence (group A) or absence (group B) of a significant severe perfusion defect at baseline before CRT. At the 3-mo follow-up, 6 of 10 group A and 8 of 9 group B patients had an improvement in New York Heart Association class. In both groups, quality of life, 6-min walking distance, and WMSI significantly improved. In group A, no significant change was registered in LVEF, LVEDVI, or LVESVI. In group B, LVEF increased from 23.1% 8% to 27.1% 11% (P 0.03) and LVEDVI and LVESVI decreased from 159 70 mL to 135 68 mL (P 0.02) and from 127 67 mL to 104 65 mL (P 0.01), reSPECTively. Conclusion: Perfusion Gated SPECT appears useful to characterize and follow up candidates for CRT. Despite clinical improvement, patients with severe resting perfusion defects do not show significant improvement in LVEF or reduction in LV volumes.
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usefulness of distinct activity thresholds according to baseline regional asynergy for predicting functional recovery in patients with chronic coronary artery disease and left ventricular dysfunction a study with nitrate enhanced sestamibi Gated SPECT
Journal of Nuclear Cardiology, 2001Co-Authors: M Leoncini, Roberto Sciagra, Gabriella Marcucci, Fabio Frascarelli, Francesco Bellandi, Michela Gallopin, A Mennuti, R P DabizziAbstract:Background The role of Gated single photon emission computed tomography (SPECT) in improving viability detection with the use of perfusion imaging is uncertain. This study aimed to verify whether the classification of baseline regional dysfunction with Gated SPECT helps to predict functional recovery with the use of quantitative perfusion imaging.
Kim A Williams - One of the best experts on this subject based on the ideXlab platform.
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left ventricular mass from Gated SPECT myocardial perfusion imaging comparison with cardiac computed tomography
Journal of Nuclear Cardiology, 2009Co-Authors: Tochi M Okwuosa, Chetan V Hampole, Javid Ali, Kim A WilliamsAbstract:Increased left ventricular mass (LVM) has been correlated with adverse cardiac events, such as sudden cardiac death. However, LVM quantitation with widely utilized Gated SPECT myocardial perfusion imaging (MPI) software, has little validation and clinical application. Thus, we compared LVM from two commonly employed Gated SPECT packages [4D-MSPECT® (4DM) and Quantitative Perfusion SPECT® (QPS)] with the 3-dimensional reference standard, CT angiography (CTA). Comparisons were made in 56 patients (mean age 61.4 ± 14.6; 32% female) referred for dual-isotope or low-dose/high-dose Tc-99m-tetrofosmin rest/stress MPI and cardiac CTA (mean 1.5 ±4.5 months apart). LVM measurement was performed for both CTA and MPI by two independent observers blinded to clinical information. Correlation with CTA was best for post-stress MPI than at rest; thus, post-stress values are reported. Values obtained with each of the techniques were very highly reproducible (interobserver correlation r = 0.99 for each technique). The mean LVM values were 142 g by CTA, 145 g by 4DM, and 135 g by QPS (P = NS for CTA vs SPECT, but P < .001 for 4DM vs QPS). There was moderately good correlation between CTA and SPECT LVM data (r = 0.74 and 0.72 for 4DM and QPS, reSPECTively; both P < .001). However, on Bland-Altman analysis there was significant overestimation of lower values and underestimation of higher CT LVM values by both QPS and 4DM (both r = 0.68 and 0.69, P < .001). The limits of agreement relative to CT LVM were wide (−52.1 g to 64.1 g for QPS; and −60.0 g to 53.5 g for 4DM). SPECT and CTA give reproducible measures of LVM. Using CTA as the reference standard, the mean SPECT LVM values are similar, but lower values are overestimated and higher values are underestimated. Thus, the SPECT values are not substitutable for CTA without mathematical correction.
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left ventricular function in patients with coronary artery disease assessed by Gated tomographic myocardial perfusion images comparison with assessment by contrast ventriculography and first pass radionuclide angiography
Journal of the American College of Cardiology, 1996Co-Authors: Kim A Williams, Linda A TaillonAbstract:Objectives. This study evaluated the use of Gated single-photon emission computed tomographic (SPECT) myocardial perfusion images for determination of left ventricular ejection fraction. Background. Gated SPECT has expanded the applications of myocardial perfusion imaging to include the evaluation of left ventricular size, regional wall motion and regional systolic thickening. Accurate automated or semi-automated methods for quantitation of left ventricular ejection fraction from tomographic perfusion images would provide additional valuable clinical information. Methods. Rest Gated SPECT was performed on the stress distribution of technetium-99m sestamibi, using eight frames per cardiac cycle. Mid-horizontal long-axis and vertical long-axis Gated tomographic perfusion images were analyzed after digital matrix inversion, which enhances edge detection, for ejection fraction determination. These ejection fractions were compared with those determined by contrast ventriculography (n = 54, including 45 biplane and 9 single plane) and first-pass radionuclide angiography (n = 38) in patients with coronary artery disease. Results. Myocardial perfusion SPECT image inversion-derived ejection fractions were slightly lower (2.7 ejection fraction units, p Conclusions. Semiautomated ejection fractions can be obtained from Gated SPECT technetium-99m sestamibi perfusion images using the image inversion technique. These results are reproducible and correlate well with results of first-pass radionuclide angiography but are closer in value to those obtained with contrast ventriculography.