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Caliskan B, Inanir M. SPECT myocardial perfusion imaging for the evaluation of left ventricular mechanical dyssynchrony in obese patients. JOURNAL OF CLINICAL ULTRASOUND : JCU 2024. [PMID: 39031559 DOI: 10.1002/jcu.23752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2024] [Revised: 06/04/2024] [Accepted: 06/08/2024] [Indexed: 07/22/2024]
Abstract
OBJECTIVE Left ventricular dyssynchrony (LVD), the loss of coordinated contraction in the left ventricle, is an early sign of heart failure. LVD can be assessed using phase analysis techniques with gated single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI). This study aimed to investigate the impact of obesity on LVD through phase analysis. METHODS We retrospectively enrolled 152 obese patients and 80 age- and sex-matched nonobese patients who showed normal myocardial perfusion and normal left ventricular ejection fraction (LVEF) on MPI. Phase standard deviation (PSD) and phase histogram bandwidth (PBW), as phase analysis parameters, were compared between patients with and without obesity. RESULTS Although PSD values were within the normal range (cut-off value >23) for both groups, the PSD values of obese patients were higher than those of the nonobese (20.49 ± 8.66 vs. 14.81 ± 4.93; p < 0.05). PBW values of obese patients were statistically significantly higher than those of the nonobese (57.03 ± 23.17 vs. 41.40 ± 9.96; p < 0.05). The PBW values of obese patients exceeded the normal limits (cut-off value >49). A weak positive correlation was observed between body mass index (BMI) and PBW values in obese patients (r = 0.181, p < 0.05). In patients of normal weight, no correlations were found between BMI and phase analysis parameters. CONCLUSION LVD may develop in obese patients, even when myocardial perfusion and ejection fraction are preserved. The use of phase analysis with gated SPECT could be an additional finding improving the early detection of left ventricular dyssynchrony in obese patients.
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Affiliation(s)
- Billur Caliskan
- Department of Nuclear Medicine, Bolu Abant Izzet Baysal University Medical Faculty, Bolu, Turkey
| | - Mehmet Inanir
- Department of Cardiology, Bolu Abant Izzet Baysal University Medical Faculty, Bolu, Turkey
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2
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Kuronuma K, Matsumoto N, Van Kriekinge SD, Slomka PJ, Berman DS. Usefulness of phase analysis on ECG gated single photon emission computed tomography myocardial perfusion imaging. J Cardiol 2023; 82:87-92. [PMID: 36858173 DOI: 10.1016/j.jjcc.2023.02.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 02/10/2023] [Indexed: 03/02/2023]
Abstract
Electrocardiogram (ECG)-gated single photon emission computed tomography myocardial perfusion imaging (GSPECT-MPI) is widely used for assessing coronary artery disease. Phase analysis on GSPECT-MPI can assess left ventricular mechanical dyssynchrony quantitatively on standard GSPECT-MPI alongside myocardial perfusion and function assessment. It has been shown that phase variables by GSPECT-MPI correlate well with tissue Doppler imaging by echocardiography. Main phase variables quantified by GSPECT-MPI are entropy, bandwidth, and phase standard deviation. Although those variables are automatically obtained from several software packages including Quantitative Gated SPECT and Emory Cardiac Toolbox, the methods for their measurement vary in each package. Several studies have shown that phase analysis has predictive value for response to cardiac resynchronization therapy and prognostic value for future adverse cardiac events beyond standard GSPECT-MPI variables. In this review, we summarize the basics of phase analysis on GSPECT-MPI and usefulness of phase analysis in clinical practice.
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Affiliation(s)
- Keiichiro Kuronuma
- Departments of Imaging, Medicine, and Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA; Department of Cardiology, Nihon University, Tokyo, Japan.
| | | | - Serge D Van Kriekinge
- Departments of Imaging, Medicine, and Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Piotr J Slomka
- Departments of Imaging, Medicine, and Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Daniel S Berman
- Departments of Imaging, Medicine, and Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA
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3
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Fudim M, Dalgaard F, Fathallah M, Iskandrian AE, Borges-Neto S. Mechanical dyssynchrony: How do we measure it, what it means, and what we can do about it. J Nucl Cardiol 2021; 28:2174-2184. [PMID: 31144228 DOI: 10.1007/s12350-019-01758-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 05/15/2019] [Indexed: 01/14/2023]
Abstract
Left ventricular mechanical dyssynchrony (LVMD) is defined by a difference in the timing of mechanical contraction or relaxation between different segments of the left ventricle (LV). Mechanical dyssynchrony is distinct from electrical dyssynchrony as measured by QRS duration and has been of increasing interest due to its association with worse prognosis and potential role in patient selection for cardiac resynchronization therapy (CRT). Although echocardiography is the most used modality to assess LVMD, some limitations apply to this modality. Compared to echo-based modalities, nuclear imaging by gated single-photon emission computed tomography (GSPECT) myocardial perfusion imaging (MPI) has clear advantages in evaluating systolic and diastolic LVMD. GSPECT MPI can determine systolic and diastolic mechanical dyssynchrony by the variability in the timing in which different LV segments contract or relax, which has prognostic impact in patients with coronary artery disease and heart failure. As such, by targeting mechanical dyssynchrony instead of electrical dyssynchrony, GSPECT MPI can potentially improve patient selection for CRT. So far, few studies have investigated the role of diastolic dyssynchrony, but recent evidence seems to suggest high prevalence and more prognostic impact than previously recognized. In the present review, we provide an oversight of mechanical dyssynchrony.
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Affiliation(s)
- Marat Fudim
- Duke University Medical Center, Duke University, 2301 Erwin Road, Durham, NC, 27710, USA.
- Duke Clinical Research Institute, Durham, NC, USA.
| | - Frederik Dalgaard
- Duke Clinical Research Institute, Durham, NC, USA
- Department of Cardiology, Herlev & Gentofte Hospital, Copenhagen, Denmark
| | | | - Ami E Iskandrian
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Salvator Borges-Neto
- Duke University Medical Center, Duke University, 2301 Erwin Road, Durham, NC, 27710, USA
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4
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AlJaroudi W. Mechanical dyssynchrony & CRT: Is it time for guideline updates? J Nucl Cardiol 2021; 28:2185-2189. [PMID: 31165384 DOI: 10.1007/s12350-019-01773-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 05/23/2019] [Indexed: 10/26/2022]
Affiliation(s)
- Wael AlJaroudi
- Division of Cardiovascular Medicine, Clemenceau Medical Center, Beirut, Lebanon.
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5
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Sreenivasan J, Jain D. Parameters of left ventricular systolic and diastolic dyssynchrony on radionuclide imaging to improve cardiac resynchronization therapy in heart failure patients with dilated cardiomyopathy. J Nucl Cardiol 2021; 28:1037-1039. [PMID: 32458330 DOI: 10.1007/s12350-020-02202-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 05/14/2020] [Indexed: 11/28/2022]
Affiliation(s)
- Jayakumar Sreenivasan
- Nuclear Cardiovascular Imaging Laboratory, Department of Cardiology, Westchester Medical Center, Valhalla, USA
| | - Diwakar Jain
- Nuclear Cardiovascular Imaging Laboratory, Department of Cardiology, Westchester Medical Center, Valhalla, USA.
- Department of Cardiovascular Medicine, New York Medical College, Westchester Medical Center, 100 Woods Road, Valhalla, NY, 10595, USA.
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Wang C, Shi J, Ge J, Tang H, He Z, Liu Y, Zhao Z, Li C, Gu K, Hou X, Chen M, Zou J, Zhou L, Garcia EV, Li D, Zhou W. Left ventricular systolic and diastolic dyssynchrony to improve cardiac resynchronization therapy response in heart failure patients with dilated cardiomyopathy. J Nucl Cardiol 2021; 28:1023-1036. [PMID: 32405991 PMCID: PMC10961703 DOI: 10.1007/s12350-020-02132-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 03/28/2020] [Indexed: 10/24/2022]
Abstract
BACKGROUND The systolic and diastolic dyssynchrony is physiologically related, but measure different left ventricular mechanisms. Left ventricular systolic mechanical dyssynchrony (systolic LVMD) has shown significant clinical values in improving cardiac resynchronization therapy (CRT) response in the heart failure patients with dilated cardiomyopathy (DCM). Our recent study demonstrated that LV diastolic dyssynchrony (diastolic LVMD) parameters have important prognostic values for DCM patients. However, there are a limited number of studies about the clinical value of diastolic LVMD for CRT. This study aims to explore the predictive values of both systolic LVMD and diastolic LVMD for CRT in DCM patients. METHODS Eighty-four consecutive CRT patients with both DCM and complete left bundle branch block (CLBBB) who received gated resting SPECT MPI at baseline were included in the present study. The phase analysis technique was applied on resting gated short-axis SPECT MPI images to measure systolic LVMD and diastolic LVMD, characterized by phase standard deviation (PSD) and phase histogram bandwidth (PBW). CRT response was defined as ≥ 5% improvement of LVEF at 6-month follow-up. Variables with P < 0.10 in the univariate analysis were included in the multivariate cox analysis. RESULTS During the follow-up period, 59.5% (50 of 84) patients were CRT responders. The univariate cox regression analysis showed that at baseline QRS duration, non-sustained ventricular tachycardia (NS-VT), systolic PSD, systolic PBW, diastolic PSD, diastolic PBW, scar burden and LV lead in the scarred myocardium were statistically significantly associated with CRT response. The multivariate cox regression analysis showed that QRS duration, NS-VT, systolic PSD, systolic PBW, diastolic PSD, and diastolic PBW were independent predictive factors for CRT response. Furthermore, the rate of CRT response was 94.4% (17 of 18) in patients whose LV lead was in the segments with both the first three late contraction and the first three late relaxation; by contrast, the rate of CRT response was only 6.7% (1 of 15, P < 0.000) in patients whose LV lead was in the segments with neither the first three late contraction nor the first three late relaxation. CONCLUSION Both systolic LVMD and diastolic LVMD from gated SPECT MPI have important predictive values for CRT response in DCM patients. Pacing at LV segments with both late contraction and late relaxation has potential to increase the CRT response.
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Affiliation(s)
- Cheng Wang
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, 210029, China
| | - Jianzhou Shi
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, 210029, China
| | - Jiacheng Ge
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, 210029, China
| | - Haipeng Tang
- School of Computing, University of Southern Mississippi, Hattiesburg, USA
| | - Zhuo He
- College of Computing, Michigan Technological University, 1400 Townsend Dr, Houghton, MI, 49931, USA
| | - Yanyun Liu
- School of Computer and Communication Engineering, Zhengzhou University of Light Industry, Zhengzhou, Henan, China
| | - Zhongqiang Zhao
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, 210029, China
| | - Chunxiang Li
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, 210029, China
| | - Kai Gu
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, 210029, China
| | - Xiaofeng Hou
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, 210029, China
| | - Minglong Chen
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, 210029, China
| | - Jiangang Zou
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, 210029, China
| | - Lei Zhou
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, 210029, China.
| | - Ernest V Garcia
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, Georgia
| | - Dianfu Li
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, 210029, China.
| | - Weihua Zhou
- College of Computing, Michigan Technological University, 1400 Townsend Dr, Houghton, MI, 49931, USA.
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Legallois D, Marie PY, Franken PR, Djaballah W, Agostini D, Manrique A. Comparison of the dyssynchrony parameters recorded with gated SPECT in ischemic cardiomyopathy according to their repeatability at rest and to their ability to detect a synchrony reserve under dobutamine infusion. J Nucl Cardiol 2020; 27:2247-2257. [PMID: 30515748 DOI: 10.1007/s12350-018-01546-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2018] [Accepted: 11/10/2018] [Indexed: 11/26/2022]
Abstract
BACKGROUND This study aimed to determine whether the repeatability of dyssynchrony assessment using gated myocardial perfusion SPECT (GSPECT) allows the detection of synchrony reserve during low-dose dobutamine infusion. METHODS AND RESULTS Sixty-one patients with ischemic cardiomyopathy and LV ejection fraction < 50% were prospectively included in 10 centers. Each patient underwent two consecutive rest GSPECT with 99mTc-labeled tracer (either tetrofosmin or sestamibi) to assess the repeatability of LV function and dyssynchrony parameters, followed by a GSECT acquisition during low-dose dobutamine infusion. LV dyssynchrony was assessed using QGS software through histogram bandwidth (BW), standard deviation of the phase (SD), and entropy. Repeatability was assessed with Lin's concordance correlation coefficient (CCC). Entropy showed a higher CCC (0.80) compared to BW (0.68) and SD (0.75). On average, dobutamine infusion yielded to improve both BW (P = .049) and entropy (P = .04) although significant improvements, setting outside the 95% confidence interval of the repeatability analysis, were documented in only 6 and 4 patients for BW and entropy, respectively. CONCLUSIONS A synchrony reserve may be documented in patients with ischemic cardiomyopathy through the recording of BW and entropy with low-dose dobutamine GSPECT, with the additional advantage of a higher repeatability for entropy.
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Affiliation(s)
- Damien Legallois
- Normandie Université, UNICAEN, Signalisation, électrophysiologie et imagerie des lésions d'ischémie-reperfusion myocardique, FHU REMOD-VHF, 14000, Caen, France
- Department of Cardiology, CHU de Caen, 14000, Caen, France
| | | | | | | | - Denis Agostini
- Normandie Université, UNICAEN, Signalisation, électrophysiologie et imagerie des lésions d'ischémie-reperfusion myocardique, FHU REMOD-VHF, 14000, Caen, France
- Department of Nuclear Medicine, CHU de Caen, 14000, Caen, France
| | - Alain Manrique
- Normandie Université, UNICAEN, Signalisation, électrophysiologie et imagerie des lésions d'ischémie-reperfusion myocardique, FHU REMOD-VHF, 14000, Caen, France.
- Department of Nuclear Medicine, CHU de Caen, 14000, Caen, France.
- Investigations chez l'Homme, GIP Cyceron PET Center, Campus Jules Horowitz, BP 5229, 14074, Caen, France.
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Heizer J, Carbone S, Billingsley HE, VAN Tassell BW, Arena R, Abbate A, Canada JM. Left ventricular concentric remodeling and impaired cardiorespiratory fitness in patients with heart failure and preserved ejection fraction. Minerva Cardiol Angiol 2020; 69:438-445. [PMID: 32996304 DOI: 10.23736/s2724-5683.20.05295-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Left ventricular (LV) concentric remodeling refers to a process by which increased LV relative wall thickness alters myocardial geometry, resulting in reduced LV end-diastolic volume (LVEDV) and stroke volume (SV). While the degree of concentric remodeling is a negative prognostic factor in heart failure with preserved ejection fraction (HFpEF), it is not known how it contributes to cardiorespiratory fitness (CRF). METHODS We performed a retrospective analysis of patients with HFpEF who underwent treadmill single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI) and cardiopulmonary exercise testing (CPX). From exercise SPECT-MPI, we recorded postexercise LVEDVi, LVESVi, SVi, LVEF, the presence and extent of perfusion defects, and perfusion reversibility. Peak oxygen consumption (VO<inf>2</inf>), the oxygen uptake efficiency slope (OUES), oxygen (O<inf>2</inf>) pulse, ventilatory efficiency (V<inf>E</inf>/VCO<inf>2</inf> slope), ventilatory anaerobic threshold, respiratory exchange ratio, exercise time, and maximum heart rate were obtained from CPX. Data are expressed as mean (±standard deviation). Univariate and multivariate linear regression was performed. RESULTS We identified 23 subjects who had completed both an exercise SPECT-MPI and a CPX. Patients were more commonly women (83%), black (65%), middle age (50 [±7.3] years), and obese (Body Mass Index [BMI] 39.7 [±6.0] kg/m2). Greater LVEDVi and LVESVi correlated positively with peak VO<inf>2</inf> (R=+0.648, P=0.001; R=+0.601, P=0.002), O<inf>2</inf> pulse (R=+0.686, P<0.001; R=+0.625, P=0.001) and OUES (R=+0.882, P<0.001; R=+0.779, P<0.001). The LVEF correlated inversely with peak VO<inf>2</inf> and OUES (R=-0.450, P=0.031; R=-0.485, P=0.035). Perfusion defect area, grade of severity, and presence of reversibility were not associated with CRF variables. CONCLUSIONS Postexercise reduced LV volumes correlate with measures of impaired CRF in patients with HFpEF, thus supporting a pathophysiologic role of concentric remodeling in impaired CRF in HFpEF.
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Affiliation(s)
- Justin Heizer
- VCU Pauley Heart Center, Virginia Commonwealth University, Richmond, VA, USA
| | - Salvatore Carbone
- VCU Pauley Heart Center, Virginia Commonwealth University, Richmond, VA, USA.,Department of Kinesiology and Health Sciences, College of Humanities and Sciences, Virginia Commonwealth University, Richmond, VA, USA
| | - Hayley E Billingsley
- VCU Pauley Heart Center, Virginia Commonwealth University, Richmond, VA, USA.,Department of Kinesiology and Health Sciences, College of Humanities and Sciences, Virginia Commonwealth University, Richmond, VA, USA
| | - Benjamin W VAN Tassell
- Department of Pharmacotherapy and Outcome Sciences, Virginia Commonwealth University, Richmond, VA, USA
| | - Ross Arena
- Department of Physical Therapy, College of Applied Health Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - Antonio Abbate
- VCU Pauley Heart Center, Virginia Commonwealth University, Richmond, VA, USA
| | - Justin M Canada
- VCU Pauley Heart Center, Virginia Commonwealth University, Richmond, VA, USA -
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Fudim M, Fathallah M, Shaw LK, James O, Samad Z, Piccini JP, Hess PL, Borges-Neto S. The prognostic value of diastolic and systolic mechanical left ventricular dyssynchrony among patients with coronary artery disease and heart failure. J Nucl Cardiol 2020; 27:1622-1632. [PMID: 31392509 DOI: 10.1007/s12350-019-01843-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2019] [Accepted: 07/20/2019] [Indexed: 10/26/2022]
Abstract
BACKGROUND Prevalence and prognostic value of diastolic and systolic dyssynchrony in patients with coronary artery disease (CAD) + heart failure (HF) or CAD alone are not well understood. METHODS We included patients with gated single-photon emission computed tomography (GSPECT) myocardial perfusion imaging (MPI) between 2003 and 2009. Patients had at least one major epicardial obstruction ≥ 50%. We assessed the association between dyssynchrony and outcomes, including all-cause and cardiovascular death. RESULTS Of the 1294 patients, HF was present in 25%. Median follow-up was 6.7 years (IQR 4.9-9.3) years with 537 recorded deaths. Patients with CAD + HF had a higher incidence of dyssynchrony than patients with CAD alone (diastolic BW 28.8% for the HF + CAD vs 14.7% for the CAD alone). Patients with CAD + HF had a lower survival than CAD alone at 10 years (33%; 95% CI 27-40 vs 59; 95% CI 55-62, P < 0.0001). With one exception, HF was found to have no statistically significant interaction with dyssynchrony measures in unadjusted and adjusted survival models. CONCLUSIONS Patients with CAD + HF have a high prevalence of mechanical dyssynchrony as measured by GSPECT MPI, and a higher mortality than CAD alone. However, clinical outcomes associated with mechanical dyssynchrony did not differ in patients with and without HF.
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Affiliation(s)
- Marat Fudim
- Division of Cardiology, Duke Department of Medicine, 2301 Erwin Road, Durham, NC, 27710, USA.
- Duke Clinical Research Institute, Durham, NC, USA.
| | - Mouhammad Fathallah
- Division of Cardiology, Duke Department of Medicine, 2301 Erwin Road, Durham, NC, 27710, USA
| | - Linda K Shaw
- Division of Cardiology, Duke Department of Medicine, 2301 Erwin Road, Durham, NC, 27710, USA
| | - Olga James
- Division of Nuclear Medicine, Duke Department of Radiology, Durham, NC, USA
| | - Zainab Samad
- Division of Cardiology, Duke Department of Medicine, 2301 Erwin Road, Durham, NC, 27710, USA
| | - Jonathan P Piccini
- Division of Cardiology, Duke Department of Medicine, 2301 Erwin Road, Durham, NC, 27710, USA
- Duke Clinical Research Institute, Durham, NC, USA
| | - Paul L Hess
- VA Eastern Colorado and Health Care System, Denver, CO, USA
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10
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Wang C, Tang H, Zhu F, Jiang Z, Shi J, Zhou Y, Garcia EV, Li D, Zhou W. Prognostic value of left-ventricular systolic and diastolic dyssynchrony measured from gated SPECT MPI in patients with dilated cardiomyopathy. J Nucl Cardiol 2020; 27:1582-1591. [PMID: 30386981 PMCID: PMC10959400 DOI: 10.1007/s12350-018-01468-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 09/20/2018] [Indexed: 12/17/2022]
Abstract
BACKGROUND Left-ventricular systolic dyssynchrony (LVSD) has been an important prognostic factor in the patients with dilated cardiomyopathy (DCM). However, the association between the LV diastolic dyssynchrony (LVDD) and clinical outcome is not well established. This study aims to evaluate the prognostic values of both systolic and diastolic dyssynchrony in patients with DCM. METHODS Fifty-two patients with DCM were enrolled and divided into two groups according to cardiac deaths from the follow-up data. The phase-analysis technique was applied on resting gated short-axis SPECT MPI images to measure LV systolic and diastolic dyssynchrony, including phase standard deviation (PSD), phase histogram bandwidth (PBW), and phase entropy (PE). Variables with P < 0.10 in the univariate analysis were included in the multivariate cox analysis. RESULTS During the follow-up period (2.9 ± 1.7 years), 18 (34.6%) cardiac deaths were observed. Compared with survivors, patients with cardiac death had lower LVEF (P = 0.011), and more severe LV systolic and diastolic dyssynchrony. The univariate cox regression analysis showed that hypertension, NT-proBNP, LVEF, systolic PSD, systolic PE, and diastolic PBW were statistically significantly associated with cardiac death. The multivariate cox regression analysis showed that systolic PE and diastolic PE were independent predictive factors for cardiac death. Furthermore, the receiver operating characteristic (ROC) analysis, when applied into the combination of systolic PE and diastolic PE for predicting cardiac death, had an area under curve (AUC) of 0.766, a sensitivity of 0.765, and a specificity of 0.722. CONCLUSIONS Both the LVSD and LVDD parameters from SPECT MPI have important prognostic values for DCM patients. Both systolic PE and diastolic PE are independent prognostic factors for cardiac death.
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Affiliation(s)
- Cheng Wang
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, 210029, China
| | - Haipeng Tang
- School of Computing, University of Southern Mississippi, 730 East Beach Blvd, Long Beach, MS, 39560, USA
| | - Fubao Zhu
- School of Computer and Communication Engineering, Zhengzhou University of Light Industry, Zhengzhou, China
| | - Zhixin Jiang
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, 210029, China
| | - Jianzhou Shi
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, 210029, China
| | - Yanli Zhou
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, 210029, China
| | - Ernest V Garcia
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, Georgia
| | - Dianfu Li
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, 210029, China.
| | - Weihua Zhou
- School of Computing, University of Southern Mississippi, 730 East Beach Blvd, Long Beach, MS, 39560, USA.
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11
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Lin WL, Wang SY, Shiau YC, Wu YW. The clinical usefulness of phase analysis in detecting coronary artery disease using dipyridamole thallium-201-gated myocardial perfusion imaging with a cadmium-zinc-telluride camera. J Nucl Cardiol 2020; 27:241-250. [PMID: 30171522 DOI: 10.1007/s12350-018-1417-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Accepted: 08/02/2018] [Indexed: 11/30/2022]
Abstract
BACKGROUND Previous studies have demonstrated left ventricular mechanical dyssynchrony (LVMD) in patients with severe coronary artery disease (CAD) with ≥ 70% stenosis. The aim of this study was to evaluate the clinical usefulness of stress/rest LVMD in the diagnosis of CAD with ≥ 50% stenosis using dipyridamole thallium-201 (Tl-201) myocardial perfusion imaging (MPI) with a cadmium-zinc-telluride camera. METHODS AND RESULTS A total of 476 patients without known CAD who underwent dipyridamole Tl-201 MPI and coronary angiography within 6 months were retrospectively reviewed. LVMD parameters including phase standard deviation and phase histogram bandwidth, phase skewness and phase kurtosis, as well as myocardial perfusion and myocardial stunning were assessed in post-stress and rest MPI. Relationships between the presence of CAD on coronary angiography and single photon emission computerized tomography (SPECT) parameters were evaluated. The presence of perfusion abnormalities was the best diagnostic tool in detecting CAD. Although less left ventricular synchrony was observed post-stress in the CAD group compared to the non-CAD group, no significant dyssynchrony was noted. CONCLUSIONS The addition of phase analysis to help diagnose CAD in Tl-201-gated SPECT with dipyridamole stress may have limited value in patients with CAD with ≥ 50% stenosis.
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Affiliation(s)
- Wan-Ling Lin
- Department of Nuclear Medicine, Far Eastern Memorial Hospital, No. 21, Sec. 2, Nanya S. Rd., Banciao Dist., New Taipei City, 220, Taiwan
- Department of Nuclear Medicine, National Taiwan University Hospital Hsin-Chu Branch, Hsinchu City, Taiwan
| | - Shan-Ying Wang
- Department of Nuclear Medicine, Far Eastern Memorial Hospital, No. 21, Sec. 2, Nanya S. Rd., Banciao Dist., New Taipei City, 220, Taiwan
| | - Yu-Chien Shiau
- Department of Nuclear Medicine, Far Eastern Memorial Hospital, No. 21, Sec. 2, Nanya S. Rd., Banciao Dist., New Taipei City, 220, Taiwan
| | - Yen-Wen Wu
- Department of Nuclear Medicine, Far Eastern Memorial Hospital, No. 21, Sec. 2, Nanya S. Rd., Banciao Dist., New Taipei City, 220, Taiwan.
- National Yang-Ming University School of Medicine, Taipei City, Taiwan.
- Department of Nuclear Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei City, Taiwan.
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Zhou W, Hung GU. Left-ventricular mechanical dyssynchrony in the prognosis of dilated cardiomyopathy: Which parameter is more useful? J Nucl Cardiol 2018; 25:1688-1691. [PMID: 28361476 DOI: 10.1007/s12350-017-0863-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 03/20/2017] [Indexed: 10/19/2022]
Affiliation(s)
- Weihua Zhou
- School of Computing, University of Southern Mississippi, Long Beach, MS, 39560, USA.
| | - Guang-Uei Hung
- Department of Nuclear Medicine, Chang Bing Show Chwan Memorial Hospital, Changhua, Taiwan.
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Petretta M, Petretta A, Cuocolo A. Assessment of asynchrony by gated myocardial perfusion imaging improves patient management: Pro. J Nucl Cardiol 2018; 25:532-535. [PMID: 28795346 DOI: 10.1007/s12350-017-1021-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Accepted: 03/10/2017] [Indexed: 10/19/2022]
Affiliation(s)
- Mario Petretta
- Department of Translational Medical Sciences, University Federico II, Naples, Italy
| | - Andrea Petretta
- Department of Arrhythmology, Maria Cecilia Hospital, GVM Care and Research, Cotignola, Italy
| | - Alberto Cuocolo
- Department of Advanced Biomedical Sciences, University Federico II, Naples, Italy.
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BMI influence on the reproducibility of ECG-gated myocardial perfusion imaging phase analysis in comparison with novel echocardiographic dyssynchrony estimation methods. Nucl Med Commun 2017; 37:767-74. [PMID: 27015078 DOI: 10.1097/mnm.0000000000000508] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
AIM Cardiac resynchronization therapy (CRT) is a treatment for patients with end-stage heart failure. However, two-thirds of the patients are nonresponders. Evaluation of left ventricular mechanical dyssynchrony may help in finding patients who will benefit from CRT. Dyssynchrony can be evaluated by the phase analysis method in myocardial perfusion imaging (MPI) or with cardiac ultrasound. The aim of this study was to investigate the reproducibility of phase analysis parameters in MPI and echocardiographic parameters in the evaluation of left ventricular mechanical dyssynchrony. In particular, the influence of BMI on reproducibility was studied. METHODS AND RESULTS Twenty-one patients underwent an ECG-gated MPI scan. Acquisition was repeated after the rest image. The patients were also studied twice with transthoracic echocardiography. Of MPI phase analysis parameters bandwidth, histogram SD and entropy% were highly reproducible in the pooled population: Cronbach's α 0.927-0.967 and intraclass correlation (ICC) 0.868-0.967, (P<0.001 for all). However, the reproducibility of bandwidth and SD was poorer in patients with BMI≥29 kg/m group (α 0.203 and -0.055; ICC 0.106 and -0.027, NS for both) than in those with BMI<29 kg/m (α 0.984 and 0.980; ICC 0.968 and 0.961, P<0.001 for both). In contrast, BMI had no obvious influence on the reproducibility of global longitudinal strain in echocardiography. CONCLUSION Parameters reflecting mechanical dyssynchrony were found to be well reproducible. However, this study indicates that phase analysis results may be less reproducible in patients with high BMI, whereas global longitudinal strain in echocardiography seems to be less critical for a patient's BMI.
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15
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Wang L, Zhou W, Liang Y, Yang Y, Garcia EV, Chen J, Fang W. Right ventricular dyssynchrony in pulmonary hypertension: Phase analysis using FDG-PET imaging. J Nucl Cardiol 2017; 24:69-78. [PMID: 26715598 PMCID: PMC10959236 DOI: 10.1007/s12350-015-0341-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2015] [Accepted: 11/06/2015] [Indexed: 11/25/2022]
Abstract
BACKGROUND Right ventricular (RV) performance in patients of pulmonary hypertension (PH) requires optimal assessment. The objective of this study is to develop phase analysis using 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) imaging as a feasible tool for evaluation of RV dyssynchrony in PH. METHODS AND RESULTS Fifty-four PH patients with well-characterized hemodynamic parameters were enrolled. All subjects performed FDG-PET imaging for RV phase analysis and RV function evaluation. Two-dimensional echocardiography with speckle tracking analysis was conducted to obtain RV time to peak systolic strain (PSST) as a comparison. The median contraction delay difference between RV middle free wall and septum measured by PET phase analysis (RVPDPET) was 20.12° (interquartile range, 4.99°-30.10°). The median difference of PSST between RV middle free wall and middle septal wall (RVPDEcho) measured by echocardiography was 43.98° (interquartile range, 6.25°-72.00°). RVPDPET was well correlated with RVPDEcho (r = 0.685, P < .001). RV phase standard deviation (RVSD) and histogram bandwidth (RVBW) derived from PET phase histogram were significantly correlated with cardiac index, RV ejection fraction, 6-minute walking distance, and serum N-terminal pro B-type natriuretic peptide (NT-proBNP) (RVSD: r = -0.532, P < .001; r = -0.551, P < .001; r = -0.544, P < .001; r = 0.404, P < .01; respectively, RVBW: r = -0.492, P < .001; r = -0.466, P < .001; r = -0.544, P < .001; r = 0.349, P = .01, respectively), while there were no significant correlations between RVSD and RVBW with hemodynamic parameters (right atrial pressure, right ventricular systolic pressure, right ventricular end-diastolic pressure, mean pulmonary artery pressure, and total pulmonary resistance). CONCLUSIONS Contraction delays between RV free wall and septum in PH measured by phase analysis and speckle tracking echocardiography were well correlated. RV dyssynchrony measured by phase analysis of FDG-PET was significantly related to RV dysfunction. Phase analysis of FDG-PET is feasible to evaluate RV mechanical dyssynchrony in patients of PH.
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Affiliation(s)
- Lei Wang
- Department of Nuclear Medicine, Fu Wai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, 167 Beilishi Road, Beijing, 100037, China
- Centre for Pharmacology and Therapeutics, Experimental Medicine, Imperial College London, London, United Kingdom
| | - Weihua Zhou
- School of Computing, University of Southern Mississippi, 730 East Beach Blvd, Long Beach, MS, 39560, USA.
| | - Yu Liang
- Department of Echocardiography, Fu Wai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100037, China
| | - Yong Yang
- Department of Nuclear Medicine, Fu Wai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, 167 Beilishi Road, Beijing, 100037, China
| | - Ernest V Garcia
- Department of Radiology, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Ji Chen
- Department of Radiology, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Wei Fang
- Department of Nuclear Medicine, Fu Wai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, 167 Beilishi Road, Beijing, 100037, China.
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Chiang KF, Cheng CM, Tsai SC, Lin WY, Chang YC, Huang JL, Hung GU, Kao CH, Chen SA, Chou P, Chen J. Relationship of myocardial substrate characteristics as assessed by myocardial perfusion imaging and cardiac reverse remodeling levels after cardiac resynchronization therapy. Ann Nucl Med 2016; 30:484-93. [DOI: 10.1007/s12149-016-1083-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2015] [Accepted: 05/12/2016] [Indexed: 11/24/2022]
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17
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Hung GU, Wang YF, Su HY, Hsieh TC, Ko CL, Yen RF. New Trends in Radionuclide Myocardial Perfusion Imaging. ACTA CARDIOLOGICA SINICA 2016; 32:156-66. [PMID: 27122946 DOI: 10.6515/acs20150803a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
UNLABELLED Radionuclide myocardial perfusion imaging (MPI) with single photon emission computed tomography (SPECT) has been widely used clinically as one of the major functional imaging modalities for patients with coronary artery disease (CAD) for decades. Ample evidence has supported the use of MPI as a useful and important tool in the diagnosis, risk stratification and treatment planning for CAD. Although popular in the United States, MPI has become the most frequently used imaging modality among all nuclear medicine tests in Taiwan. However, it should be acknowledged that MPI SPECT does have its limitations. These include false-positive results due to certain artifacts, false-negative due to balanced ischemia, complexity and adverse reaction arising from current pharmacological stressors, time consuming nature of the imaging procedure, no blood flow quantitation and relatively high radiation exposure. The purpose of this article was to review the recent trends in nuclear cardiology, including the utilization of positron emission tomography (PET) for MPI, new stressor, new SPECT camera with higher resolution and higher sensitivity, dynamic SPECT protocol for blood flow quantitation, new software of phase analysis for evaluation of LV dyssynchrony, and measures utilized for reducing radiation exposure of MPI. KEY WORDS Coronary artery disease • Myocardial flow reserve • Myocardial perfusion imaging • Phase analysis • PET • SPECT.
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Affiliation(s)
- Guang-Uei Hung
- Department of Nuclear Medicine, Chang Bing Show Chwan Memorial Hospital, Changhua
| | - Yuh-Feng Wang
- Department of Nuclear Medicine, Buddhist Dalin Tzu Chi General Hospital, Chiayi; ; School of Medicine, Tzu Chi University, Hualian
| | - Hung-Yi Su
- Department of Nuclear Medicine, Cathay General Hospital, Taipei
| | - Te-Chun Hsieh
- Department of Nuclear Medicine and PET Center, China Medical University Hospital; ; Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung
| | - Chi-Lun Ko
- Department of Nuclear Medicine, National Taiwan University Hospital Yun-Lin Branch, Yun-Lin
| | - Ruoh-Fang Yen
- Department of Nuclear Medicine, National Taiwan University Hospital; ; Department of Radiology, National Taiwan University College of Medicine, Taipei, Taiwan
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Tsai SC, Chang YC, Chiang KF, Lin WY, Huang JL, Hung GU, Kao CH, Chen J. LV Dyssynchrony Is Helpful in Predicting Ventricular Arrhythmia in Ischemic Cardiomyopathy After Cardiac Resynchronization Therapy: A Preliminary Study. Medicine (Baltimore) 2016; 95:e2840. [PMID: 26886645 PMCID: PMC4998645 DOI: 10.1097/md.0000000000002840] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
For patients with coronary artery disease, larger scar burdens are associated with higher risk of ventricular arrhythmia. Left ventricular (LV) dyssynchrony is associated with increased risk of sudden cardiac death in patients with heart failure. The purpose of this study was to assess the values of LV dyssynchrony and myocardial scar assessed by myocardial perfusion SPECT (MPS) in predicting the development of ventricular arrhythmia in ischemic cardiomyopathy. Twenty-two patients (16 males, mean age: 66 ± 13) with irreversible ischemic cardiomyopathy received cardiac resynchronization therapy (CRT) for at least 12 months were enrolled for MPS. Quantitative parameters, including LV dyssynchrony with phase standard deviation (phase SD) and bandwidth, left ventricular ejection fraction (LVEF), and scar (% of total areas), were generated by Emory Cardiac Toolbox. Ventricular tachycardia (VT) and ventricular fibrillation (VF) recorded in the CRT device during follow-up were used as the reference standard of diagnosing ventricular arrhythmia. Stepwise logistic regression analysis was performed for determining the independent predictors of VT/VF and receiver operating characteristic (ROC) curve analysis was used for generating the optimal cut-off values for predicting VT/VF. Nine (41%) of the 22 patients developed VT/VF during the follow-up periods. Patients with VT/VF had significantly lower LVEF, larger scar, larger phase SD, and larger bandwidth (all P < 0.05). Logistic regression analysis showed LVEF and bandwidth were independent predictors of VT/VF. ROC curve analysis showed the areas under the curves were 0.71 and 0.83 for LVEF and bandwidth, respectively. The optimal cut-off values were <36% and > 139° for LVEF and bandwidth, respectively. The sensitivity, specificity, positive predictive value, and negative predictive value were 100%, 39%, 53%, and 100%, respectively, for LVEF; and were 78%, 92%, 88%, and 86%, respectively, for bandwidth. LV dyssynchrony as assessed by phase analysis of MPS is helpful for predicting ventricular arrhythmia in ischemic cardiomyopathy after CRT. Further implantation of defibrillator may be considered for those patients with bandwidth >139°.
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Affiliation(s)
- Shih-Chuan Tsai
- From the Department of Nuclear Medicine (S-CT, W-YL) and Cadiovascular Center (Y-CC, K-FC, J-LH), Taichung Veterans General Hospital; Department of Medical Imaging and Radiological Sciences (S-CT, G-UH), Central Taiwan University of Science and Technology; Department of Nuclear Medicine (G-UH), Chang Bing Show Chwan Memorial Hospital, Changhua, Taiwan; Department of Medical Imaging and Radiological Sciences, China Medical University, Taichung, Taiwan (G-UH, C-HK); Department of Medicine, School of Medicine, Institute of Clinical Medicine, and Cardiovascular Research Institute, National Yang-Ming University, Taipei, Taiwan (J-LH); and Department of Radiology and Imaging Sciences (JC), Emory University School of Medicine, Atlanta, GA
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Abstract
Phase analysis of gated myocardial perfusion single-photon emission computed tomography is a widely available and reproducible measure of left ventricular (LV) dyssynchrony, which also provides comprehensive assessment of LV function, global and regional scar burden, and patterns of LV mechanical activation. Preliminary studies indicate potential use in predicting cardiac resynchronization therapy response and elucidation of mechanisms. Because advances in technology may expand capabilities for precise LV lead placement in the future, identification of specific patterns of dyssynchrony may have a critical role in guiding cardiac resynchronization therapy.
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20
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Relationship of quantitative parameters of myocardial perfusion SPECT and ventricular arrhythmia in patients receiving cardiac resynchronization therapy. Ann Nucl Med 2015; 29:772-8. [DOI: 10.1007/s12149-015-1007-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2015] [Accepted: 07/06/2015] [Indexed: 12/01/2022]
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21
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Soman P, Chen J. Left ventricular dyssynchrony assessment using myocardial single-photon emission CT. Semin Nucl Med 2015; 44:314-9. [PMID: 24948153 DOI: 10.1053/j.semnuclmed.2014.04.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Myocardial SPECT using standard procedure for perfusion imaging and phase analysis is a novel approach to left ventricular dyssynchrony assessment. Preliminary data suggest excellent repeatability and potential utility for guiding cardiac resynchronization therapy and elucidating mechanisms.
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Affiliation(s)
- Prem Soman
- Division of Cardiology, University of Pittsburgh, Pittsburgh, PA.
| | - Ji Chen
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA
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Ozdemir S, Kırılmaz B, Barutçu A, Tan YZ, Çelik F, Akgoz S. The evaluation of left ventricular dyssynchronization in patients with hypertension by phase analysis of myocardial perfusion-gated SPECT. Ann Nucl Med 2014; 29:240-7. [DOI: 10.1007/s12149-014-0933-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Accepted: 11/19/2014] [Indexed: 12/01/2022]
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