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Bomela W, Sebek M, Nagao R, Singhal B, Kiss IZ, Li JS. Finding influential nodes in networks using pinning control: Centrality measures confirmed with electrochemical oscillators. CHAOS (WOODBURY, N.Y.) 2023; 33:093128. [PMID: 37729101 PMCID: PMC10513758 DOI: 10.1063/5.0163899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Accepted: 08/22/2023] [Indexed: 09/22/2023]
Abstract
The spatiotemporal organization of networks of dynamical units can break down resulting in diseases (e.g., in the brain) or large-scale malfunctions (e.g., power grid blackouts). Re-establishment of function then requires identification of the optimal intervention site from which the network behavior is most efficiently re-stabilized. Here, we consider one such scenario with a network of units with oscillatory dynamics, which can be suppressed by sufficiently strong coupling and stabilizing a single unit, i.e., pinning control. We analyze the stability of the network with hyperbolas in the control gain vs coupling strength state space and identify the most influential node (MIN) as the node that requires the weakest coupling to stabilize the network in the limit of very strong control gain. A computationally efficient method, based on the Moore-Penrose pseudoinverse of the network Laplacian matrix, was found to be efficient in identifying the MIN. In addition, we have found that in some networks, the MIN relocates when the control gain is changed, and thus, different nodes are the most influential ones for weakly and strongly coupled networks. A control theoretic measure is proposed to identify networks with unique or relocating MINs. We have identified real-world networks with relocating MINs, such as social and power grid networks. The results were confirmed in experiments with networks of chemical reactions, where oscillations in the networks were effectively suppressed through the pinning of a single reaction site determined by the computational method.
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Affiliation(s)
- Walter Bomela
- Department of Electrical and Systems Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, USA
| | - Michael Sebek
- Department of Physics and Center for Complex Network Research, Northeastern University, Boston, Massachusetts 02115, USA
| | - Raphael Nagao
- Institute of Chemistry, Department of Physical Chemistry, University of Campinas, Campinas, SP 13083-970, Brazil
| | - Bharat Singhal
- Department of Electrical and Systems Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, USA
| | - István Z. Kiss
- Department of Chemistry, Saint Louis University, St. Louis, Missouri 63103, USA
| | - Jr-Shin Li
- Department of Electrical and Systems Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, USA
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Gehlen H, Bildheim LM. Speckle-tracking analysis of myocardial deformation in correlation to age in healthy horses. J Vet Sci 2018; 19:676-682. [PMID: 29695144 PMCID: PMC6167342 DOI: 10.4142/jvs.2018.19.5.676] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 03/13/2018] [Accepted: 04/23/2018] [Indexed: 11/20/2022] Open
Abstract
An effect of aging on cardiac morphology and function has been shown in humans. In horses, cardiac wall motion analysis using two-dimensional speckle tracking (2D-ST) has not yet been reported. Our study included 57 horses of different warmblood breeds between 3 and 30 years old. Age had a significant influence on left ventricular free wall (LVFW) systolic strain rate (p ≤ 0.05) and early diastolic relaxation (p ≤ 0.01). In the interventricular septum (IVS), systolic (p ≤ 0.01) and late diastolic (p ≤ 0.05) contraction velocities also increased with age. In our study, 2D-ST revealed important information on myocardial function, which was most evident in the LVFW, where measurements were highly reproducible. Aging seems to be associated with structural changes within the myocardium and with decreasing contraction capacity in old animals. These physiological, age-related processes should be considered when performing cardiac wall motion analysis of the 2D-ST results for the LVFW and IVS in horses.
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Affiliation(s)
- Heidrun Gehlen
- Equine Clinic, Freie Universitaet Berlin, 14195 Berlin, Germany
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3
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Evaluation of the effect of non-ergot dopamine agonists on left ventricular systolic function with speckle tracking echocardiography. Anatol J Cardiol 2018; 20:213-219. [PMID: 30297579 PMCID: PMC6249529 DOI: 10.14744/anatoljcardiol.2018.65983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Objective: Parkinson’s disease (PD) is a neurological disorder, and ergot dopamine agonists (DAs) are no longer usually preferred in the treatment due to the increased risk of valvular heart disease. Some recent studies have shown that commonly used non-ergot DA also increases the risk of heart failure. On the other hand, there are studies showing conflicting data about this relationship. The aim of the present study was to investigate the cardiac effects of non-ergot DAs in patients with PD using echocardiography. Methods: Conventional echocardiography and two-dimensional (2D) speckle tracking strain echocardiography were performed to determine the possible systolic dysfunction prior to the development of apparent systolic heart failure. Ninety-one (55 male, 64±10 years) patients with PD were included in the study. Furthermore, 25 subjects with newly diagnosed PD and using no drug were enrolled as the control group. All patients were divided into groups according to their medication. Patients using levodopa were classified as Group 1 (36), levodopa+pramipexole as Group 2 (27), and levodopa+ropinirole as Group 3 (28). Results: Left ventricle dysfunction with non-ergot DA use in patients with PD was not established with conventional echocardiographic evaluation. For 2D strain analysis, global longitudinal strain values were obtained as −18.5%, −18.5%, and −18.9% in the groups, respectively. Strain and strain rate values of the left ventricle were not different between the groups (p=0.816 and p=0.881, respectively). Conclusion: There was no significant relationship between left ventricular dysfunction and use of non-ergot DA in patients with PD. Similar results were obtained in strain analysis showing left ventricular subclinical dysfunction. Our study appears to confirm the safety of non-ergot DA in the point of heart failure risk. To our knowledge, this is the first study to evaluate the effect of this group of drugs on subclinical left ventricular systolic function.
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Abstract
Biventricular pacing has been an exciting recent advance in the management of drug-refractory heart failure. This new therapy has evolved as much from necessity as scientific observation, since benefits derived from pharmacotherapy currently appear to have reached their peak. Clinical trials of biventricular pacing are establishing morbidity and mortality benefits in heart failure. New challenges in the use of these pacemakers are now arising. These include the accurate diagnosis of ventricular dyssynchrony and, hence, potential responders to the refinement of implantation of the left ventricular lead to the appropriate dyssynchronous ventricular area and optimization of pacemaker programming. This review gives a general overview of the principles and the current evidence for the use of biventricular pacemakers in the treatment of heart failure. In addition, a discussion of current research and future projects is included.
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Affiliation(s)
- Paul A Gould
- Wynn Department of Metabolic Cardiology, Baker Heart Research Institute, PO Box 6492, Melbourne, Victoria 8008, Australia.
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Dubin AM, Berul CI. Electrophysiological interventions for treatment of congestive heart failure in pediatrics and congenital heart disease. Expert Rev Cardiovasc Ther 2014; 5:111-8. [PMID: 17187462 DOI: 10.1586/14779072.5.1.111] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Heart failure therapy, while well tested in the adult population, therapeutic interventions are less well defined in the pediatric population. Several treatment strategies are available for the adult patient with heart failure, thought few of these therapies have been proven in children. Morbidity and mortality in the pediatric population with a failing heart is significant, and rhythm management as well as strategies to improve hemodynamics are important in the care of these children. This review will address issues of rhythm management and resynchronization therapy in pediatric and congenital heart disease patients with heart failure.
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Affiliation(s)
- Anne M Dubin
- Stanford University, 750 Welch Rd., Suite 305, Palo Alto, CA 94304, USA.
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de Sá LAB, Rassi S, Batista MAL. Is conventional cardiac pacing harmful in patients with normal ventricular function? Arq Bras Cardiol 2013; 101:545-53. [PMID: 24145393 PMCID: PMC4106813 DOI: 10.5935/abc.20130205] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2013] [Revised: 07/16/2013] [Accepted: 07/22/2013] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Right ventricular pacing may be deleterious in patients with left ventricular dysfunction, but in patients with normal function the impact of this stimulation triggering clinically relevant ventricular dysfunction is not fully established. OBJECTIVES To evaluate the clinical, echocardiographic findings of patients with previously normal left ventricular function underwent implantation of a pacemaker. METHODS Observational, cross-sectional study with 20 patients, who underwent implantation of pacemaker, prospectively followed-up, with the following inclusion criteria: normal left ventricular function defined by echocardiography and ventricular pacing higher than 90%. Were evaluated functional class (FC) (New York Heart Association), 6-minute walk test (6MWT), B-type natriuretic peptide (BNP), echocardiographic assessment (conventional and dyssynchrony parameters), and quality of life questionnaire (QLQ) (SF-36). The assessment was performed at ten days (t1), four months (t2), eight months (t3), 12 months (t4) and 24 months (t5). RESULTS Conventional echocardiographic parameters and dyssynchrony parameters showed statistically significant variation over time. The 6MWT, FC, and BNP showed worsening at the end of two years. QLQ showed initial improvement and worsening at the end of two years. CONCLUSION The implantation of conventional pacemaker was associated with worsening in functional class, worsening in walk test, increased BNP levels, increased duration of QRS, and worsening in some domains of the QLQ at the end of two years. There were no changes in echocardiography measurements (conventional and asynchrony measures).
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Chang PC, Wo HT, Chen TH, Wu D, Lin FC, Wang CC. Remote past left ventricular function before chronic right ventricular pacing predicts responses to cardiac resynchronization therapy upgrade. PACING AND CLINICAL ELECTROPHYSIOLOGY: PACE 2013; 37:454-63. [PMID: 24251726 DOI: 10.1111/pace.12291] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Revised: 08/05/2013] [Accepted: 09/03/2013] [Indexed: 01/29/2023]
Abstract
BACKGROUND This study examined factors that could predict response to cardiac resynchronization therapy (CRT) upgrade in patients who developed heart failure (HF) after long-term right ventricular (RV) pacing. METHODS Twenty-five consecutive patients who received CRT upgrade for long-term RV pacing (RVP) were enrolled in this study. None of these patients were eligible for CRT at the moment of starting RVP. After 5.7 ± 4.0 years chronic RVP, these 25 patients developed HF symptoms and received CRT upgrade. Echocardiography was conducted at the moment of CRT upgrade and 6 months after CRT. Remote past left ventricular ejection fraction (RP-LVEF) at the moment of starting RVP was retrospectively obtained from the echocardiographic and cardiac catherization reports. Responders were defined as a reduction in LV end-systolic volume (LVESV) ≥ 15%. Their clinical and echocardiographic parameters were analyzed and compared. RESULTS Responders had significant higher RP-LVEF as compared to nonresponders (53.6 ± 16.5% vs 31.4 ± 11.6%, P = 0.002). RP-LVEF correlated with reduction in LVESV after CRT upgrade (P < 0.001). RP-LVEF ≥ 43.5% as a cutoff value predicted response to CRT upgrade with an area under the receiver-operating curve of 0.87, a sensitivity of 78%, and a specificity of 100%. Intrinsic QRS width, septal-posterior wall motion delay, or tissue Doppler-derived dyssynchrony indexes did not predict responses to CRT upgrade. CONCLUSION In long-term RVP patients who developed HF and received CRT upgrade, RP-LVEF ≥ 43.5% predicts good response. Conventional dyssynchrony indexes do not predict responses to CRT upgrade in these patients.
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Affiliation(s)
- Po-Cheng Chang
- Second Section of Cardiology, Department of Medicine, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Taoyuan, Taiwan
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Chua J, Schwarzenberger J, Mahajan A. Optimization of Pacing After Cardiopulmonary Bypass. J Cardiothorac Vasc Anesth 2012; 26:291-301. [DOI: 10.1053/j.jvca.2011.07.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2011] [Indexed: 11/11/2022]
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Perry R, De Pasquale CG, Chew DP, McGavigan AD, Joseph MX. Tissue Doppler Derived Mechanical Dyssynchrony Does Not Change after Cardiac Resynchronization Therapy. Echocardiography 2011; 28:961-7. [DOI: 10.1111/j.1540-8175.2011.01498.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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10
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Misra N, Webber SA, DeGroff CG. Adult Definitions for Dyssynchrony Are Inappropriate for Pediatric Patients. Echocardiography 2011; 28:468-74. [DOI: 10.1111/j.1540-8175.2010.01348.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Kleemann T, Becker T, Strauss M, Dyck N, Schneider S, Weisse U, Saggau W, Cornelius B, Layer G, Seidl K. Impact of left ventricular lead position on the incidence of ventricular arrhythmia and clinical outcome in patients with cardiac resynchronization therapy. J Interv Card Electrophysiol 2010; 28:109-16. [DOI: 10.1007/s10840-010-9470-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2009] [Accepted: 01/17/2010] [Indexed: 11/25/2022]
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12
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Carasso S, Rakowski H, Witte KK, Smith P, Carasso D, Garceau P, Sasson Z, Parker JD. Left Ventricular Strain Patterns in Dilated Cardiomyopathy Predict Response to Cardiac Resynchronization Therapy: Timing Is Not Everything. J Am Soc Echocardiogr 2009; 22:242-50. [DOI: 10.1016/j.echo.2008.12.003] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2008] [Indexed: 10/21/2022]
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13
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Mohammed A, Friedberg MK. Feasibility of a New Tissue Doppler Based Method for Comprehensive Evaluation of Left-Ventricular Intra-Ventricular Mechanical Dyssynchrony in Children With Dilated Cardiomyopathy. J Am Soc Echocardiogr 2008; 21:1062-7. [DOI: 10.1016/j.echo.2008.06.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2008] [Indexed: 12/15/2022]
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Repeatability and reproducibility of phase analysis of gated single-photon emission computed tomography myocardial perfusion imaging used to quantify cardiac dyssynchrony. Nucl Med Commun 2008; 29:374-81. [PMID: 18317303 DOI: 10.1097/mnm.0b013e3282f81380] [Citation(s) in RCA: 115] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
BACKGROUND A novel method to quantify dyssynchrony has been developed using phase analysis of gated single-photon emission computed tomography perfusion imaging. We report on the effect of variability in image reconstruction on the phase analysis results (repeatability) and on the interobserver and intraobserver reproducibility of the technique. METHODS Phase standard deviation (SD) and bandwidth are phase indices that quantify dyssynchrony. To evaluate repeatability, raw data sets were processed twice in 50 patients with left ventricular dysfunction and 50 normal controls. To determine the optimal processing method, two replicated phase analysis results were obtained using automated and manual base parameter placement. Reproducibility of the phase analysis was determined using the data from 20 patients. RESULTS In normal controls, manual base parameter placement improves repeatability of the phase analysis as measured by the mean absolute difference between two reads for phase SD (12.0 degrees vs. 1.2 degrees , P<0.0001) and bandwidth (33.7 degrees vs. 3.6 degrees , P<0.0001). Repeatability is better for normal controls than for patients with left ventricular dysfunction for phase SD (1.2 degrees vs. 6.0 degrees , P<0.0001) and bandwidth (3.6 degrees vs. 26.5 degrees , P<0.0001). Reproducibility of the phase analysis is high as measured by the intraclass correlation coefficients for phase SD and bandwidth of 0.99 and 0.99 for the interobserver comparisons and 1.00 and 1.00 for the intraobserver comparisons. CONCLUSION A novel method to quantify dyssynchrony has been developed using gated single-photon emission computed tomography perfusion imaging. Manual base parameter placement reduces the effect that variability in image reconstruction has on phase analysis. A high degree of reproducibility of phase analysis is observed.
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Abstract
There are several options now available for the management of arrhythmias and ventricular dysfunction in pediatric patients with heart failure. A hybrid approach that combines the expertise of heart failure and electrophysiology specialists may be well suited for the optimal management of these complex patients. Medical and device therapies may be synergistic in decreasing the morbidity and mortality in pediatric heart failure. Pediatric electrophysiology can now potentially offer therapies that can help prevent both arrhythmic and pump failure deaths, as well as improve functional capacity and quality of life. These therapies and the available supporting data relevant to pediatrics will be the focus of this review.
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16
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Gorcsan J, Abraham T, Agler DA, Bax JJ, Derumeaux G, Grimm RA, Martin R, Steinberg JS, Sutton MSJ, Yu CM. Echocardiography for Cardiac Resynchronization Therapy: Recommendations for Performance and Reporting–A Report from the American Society of Echocardiography Dyssynchrony Writing Group Endorsed by the Heart Rhythm Society. J Am Soc Echocardiogr 2008; 21:191-213. [PMID: 18314047 DOI: 10.1016/j.echo.2008.01.003] [Citation(s) in RCA: 385] [Impact Index Per Article: 24.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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17
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Takamatsu H, Tada H, Okaniwa H, Toide H, Maruyama H, Higuchi R, Kaseno K, Naito S, Kurabayashi M, Oshima S, Taniguchi K. Right Bundle Branch Block and Impaired Left Ventricular Function as Evidence of a Left Ventricular Conduction Delay. Circ J 2008; 72:120-6. [DOI: 10.1253/circj.72.120] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
| | - Hiroshi Tada
- Division of Cardiology, Gunma Prefectural Cardiovascular Center
| | - Hiroki Okaniwa
- Division of Cardiology, Gunma Prefectural Cardiovascular Center
| | - Hiroyuki Toide
- Division of Cardiology, Gunma Prefectural Cardiovascular Center
| | - Hiroko Maruyama
- Division of Cardiology, Gunma Prefectural Cardiovascular Center
| | - Rumi Higuchi
- Division of Cardiology, Gunma Prefectural Cardiovascular Center
| | - Kenichi Kaseno
- Division of Cardiology, Gunma Prefectural Cardiovascular Center
| | - Shigeto Naito
- Division of Cardiology, Gunma Prefectural Cardiovascular Center
| | - Masahiko Kurabayashi
- Gunma University Graduate School of Medicine, Department of Medicine and Biological Science
| | - Shigeru Oshima
- Division of Cardiology, Gunma Prefectural Cardiovascular Center
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Bleeker GB, Yu CM, Nihoyannopoulos P, de Sutter J, Van de Veire N, Holman ER, Schalij MJ, van der Wall EE, Bax JJ. Optimal use of echocardiography in cardiac resynchronisation therapy. Heart 2007; 93:1339-50. [PMID: 17933989 DOI: 10.1136/hrt.2005.076422] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Echocardiography has several roles in patients with cardiac resynchronisation therapy (CRT). First, it can optimise selection of CRT candidates by demonstration of left ventricular (LV) dyssynchrony. Second, it can be used to assess immediate response to CRT, including detection of acute LV resynchronisation. Echocardiography is also useful to evaluate long-term benefit from CRT. Finally, echocardiography is important in optimisation of pacemaker settings, including AV and VV optimisation.
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Affiliation(s)
- Gabe B Bleeker
- Department of Cardiology, Leiden University Medical Centre, Leiden, The Netherlands.
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Artis NJ, Oxborough DL, Williams G, Pepper CB, Tan LB. Two-dimensional strain imaging: a new echocardiographic advance with research and clinical applications. Int J Cardiol 2007; 123:240-8. [PMID: 17477993 DOI: 10.1016/j.ijcard.2007.02.046] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2006] [Revised: 02/02/2007] [Accepted: 02/17/2007] [Indexed: 11/27/2022]
Abstract
Over the past two decades the quest for quantitative evaluation of left ventricular function and regional wall motion has escalated, allowing several aspects of myocardial contractile patterns to be quantified, both during stress echocardiography and in the assessment of dyssynchrony. Most of the literature to date has used Tissue Doppler Imaging (TDI) techniques to assess essentially long-axis function due to the angle dependency of Doppler based techniques. This brief review introduces the early development, validation and potential clinical applications of a new technique of quantifying two-dimensional (radial and circumferential) strains and strain rates through tracking myocardial "speckles". In-vivo and in-vitro validation of this 2D-strain imaging technique has been undertaken and reached a point where it is considered ready for more widespread investigations into clinical utility. One important advantage over TDI techniques is that it is not limited by dependency on the angle of insonation. Several recent studies looking at ventricular function in specific groups of patients have reported practical ability to distinguish the abnormally from the normally contracting regions of ventricular walls. It provides new and complementary quantitative information about ventricular dyssynchrony and regional wall motion abnormalities. More research studies are needed to determine the sensitivity and specificity of the measurements obtained using this technique and define its strengths and limitations. In particular, whether the measured values correlate well with clinical outcomes will need to be established in longitudinal interventional studies. The clinical utilities of this technique over the coming years are likely to expand rapidly.
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Affiliation(s)
- N J Artis
- University of Leeds, Leeds, LS2 9JT, UK
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20
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Murphy RT, Sigurdsson G, Mulamalla S, Agler D, Popovic ZB, Starling RC, Wilkoff BL, Thomas JD, Grimm RA. Tissue synchronization imaging and optimal left ventricular pacing site in cardiac resynchronization therapy. Am J Cardiol 2006; 97:1615-21. [PMID: 16728225 DOI: 10.1016/j.amjcard.2005.12.054] [Citation(s) in RCA: 148] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2005] [Revised: 12/20/2005] [Accepted: 12/20/2005] [Indexed: 11/24/2022]
Abstract
The optimal pacing site in cardiac resynchronization therapy (CRT) remains controversial. Tissue synchronization imaging is a novel echocardiographic technique that color-codes for areas of maximal delay in myocardial velocities. This study aimed to identify whether the left ventricular (LV) pacing lead position in CRT should be guided by a patient's area of maximal mechanical delay. Fifty-four patients with advanced heart failure were assessed echocardiographically before and 6 months after CRT. Response was analyzed according to the relation between the LV lead position and the area of maximal delay to peak velocity by tissue synchronization imaging in the first half of the ejection phase: group 1 (n = 22) had lead placement corresponding to the segment of maximal delay; group 2 (n = 13) had lead placement 1 segment adjacent; and group 3 (n = 19) had lead placement remote from this site. Evidence of LV reverse remodeling and improved systolic function was documented in group 1 (mean percentage decrease in end-systolic volume 23%) more than in group 2 (mean decrease 15%), and more than in group 3 (mean increase 8.9%, p <0.0001 compared with groups 1 and 2). In group 1, 16 of 22 patients had reverse remodeling (>15% decrease in end-systolic volume); reverse remodeling was seen in 7 of 13 patients in group 2 and 1 of 19 in group 3. The placing of the lead position proximal to the site of maximal delay by tissue synchronization imaging was correlated with reverse remodeling (r = 0.449, p = 001). Of 7 patients with delay confined to the septum and anterior wall only, none had evidence of reverse remodeling after CRT. In conclusion, pacing at the site of maximal mechanical delay was associated with reverse remodeling. Individually tailored LV lead positioning should be considered before CRT.
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Affiliation(s)
- Ross T Murphy
- Department of Cardiovascular Medicine, Cleveland Clinic Foundation, Cleveland, Ohio, USA
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21
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Khairy P, Fournier A, Thibault B, Dubuc M, Thérien J, Vobecky SJ. Cardiac resynchronization therapy in congenital heart disease. Int J Cardiol 2006; 109:160-8. [PMID: 16095734 DOI: 10.1016/j.ijcard.2005.06.065] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2005] [Revised: 06/02/2005] [Accepted: 06/10/2005] [Indexed: 12/01/2022]
Abstract
While cardiac resynchronization therapy (CRT) is of proven benefit in selected patients with severe ischemic or dilated cardiomyopathy, refractory symptoms, and conduction delay, extrapolation to congenital heart disease is not straightforward. This rapidly expanding patient population commonly suffers from heart failure, particularly in the presence of a single or systemic right ventricle. Surgical repair may also contribute to ventricular asynchrony. In this systematic review, the current state of knowledge regarding CRT in congenital heart disease is presented. Issues specific to congenital heart disease including right bundle branch block, right (pulmonary) ventricular dysfunction, systemic right ventricular dysfunction, and single ventricle dysfunction are explored. Evidence-based CRT applications for each of these particular conditions are reviewed. Initial experience with CRT in the acute postoperative setting and longer-term, including our own, is elaborated. Unlike standard indications based on multiple randomized clinical trials, supporting evidence for CRT in congenital heart disease is limited to case reports, case series, and small experimental crossover studies in the acute postoperative setting. The heterogeneous patient population, technical limitations from patient size, vascular access issues, and unique forms of ventricular asynchrony further obscure the selection of potential beneficiaries. Despite these limitations, experience thus far has been favorable. Quality of current data precludes definitive evidence-based recommendations, but optimistic initial results suggest that research endeavors in this field should be pursued. Multicenter prospective collaborative efforts are to be encouraged.
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Affiliation(s)
- Paul Khairy
- Electrophysiology and Adult Congenital Heart Services, Montreal Heart Institute, Canada.
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22
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Yu CM, Zhang Q, Chan YS, Chan CK, Yip GWK, Kum LCC, Wu EB, Lee PW, Lam YY, Chan S, Fung JWH. Tissue Doppler velocity is superior to displacement and strain mapping in predicting left ventricular reverse remodelling response after cardiac resynchronisation therapy. Heart 2006; 92:1452-6. [PMID: 16621873 PMCID: PMC1861066 DOI: 10.1136/hrt.2005.083592] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
OBJECTIVE To compare the values of three different forms of tissue Doppler imaging (TDI) processing in predicting left ventricular (LV) reverse remodelling-namely, tissue velocity, displacement and strain mapping. DESIGN Standard echocardiography with TDI was performed before and 3 months after cardiac resynchronisation therapy (CRT). SETTING University teaching hospital. PATIENTS 55 patients with heart failure who received CRT and were followed up for at least 3 months were recruited. INTERVENTIONS During off-line analysis, the time to peak systolic velocity in the ejection phase, time to peak positive displacement and time to peak negative strain were measured in the six basal, six mid-segmental model. Parameters of systolic asynchrony derived by velocity, displacement and strain mapping were correlated with percentage reduction in LV end systolic volume (LVESV) and absolute gain in ejection fraction (EF). RESULTS Among the three TDI processing technologies, all parameters of tissue velocity correlated with LV reverse remodelling (r = -0.49 to r = -0.76, all p < 0.001), but the predictive value was strongest in models with 12 LV segments. For displacement mapping, only the two parameters that included 12 LV segments correlated modestly with reduction in LVESV (r = -0.36, p < 0.05) and gain in EF. However, none of the strain mapping parameters predicted a favourable echocardiographic response. The receiver operating characteristic (ROC) curve areas were higher for parameters of tissue velocity based on 12 LV segments (ROC areas 0.88 and 0.94) than the corresponding areas derived from displacement mapping (ROC areas 0.72 and 0.71). CONCLUSION Tissue velocity parameters of systolic asynchrony are superior to those of displacement and strain mapping in predicting LV reverse remodelling response after CRT.
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Affiliation(s)
- C-M Yu
- Division of Cardiology, S H Ho Cardiovascular and Stroke Centre, Department of Medicine and Therapeutics, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, NT, Hong Kong.
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23
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Borges AC, Knebel F, Eddicks S, Bondke HJ, Baumann G. [Echocardiographic evaluation to select patients for cardiac resynchronization therapy]. Herzschrittmacherther Elektrophysiol 2006; 17 Suppl 1:I63-72. [PMID: 16598624 DOI: 10.1007/s00399-006-1110-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Wide QRS complex and asynchronous myocardial contraction in heart failure are associated with poor prognosis. Resynchronization can be achieved by biventricular pacing (BVP), which leads to hemodynamic and clinical improvement and reverse remodeling, and may improve survival. However, there is a substantial subset of patients with wide QRS complexes in the electrocardiogram who does not improve despite BVP, and there are findings which suggest that resynchronization therapy may be also beneficial for heart failure patients with normal QRS duration. QRS width predicts the benefit of BVP only with limitation and only correlates weakly with echocardiographically determined myocardial asynchrony. Determination of asynchrony by tissue Doppler echocardiography seems to be the best predictor for improvement after BVP, although no consensus on the optimal method to assess asynchrony has yet been achieved. To date, most studies evaluating tissue Doppler echo in BVP were performed retrospectively and only one prospective study with patient selection for BVP according to echocardiography and electrocardiography criteria of asynchrony has been published. These new echocardiographic tools will help to prospectively select patients for BVP, help to guide implantation and to optimize device programming.
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Affiliation(s)
- A C Borges
- Medizinische Klinik der Charité, Charité Campus Mitte-Universitätsmedizin Berlin, Schumannstr. 20-21, 10117 Berlin.
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24
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Hawkins NM, Petrie MC, MacDonald MR, Hogg KJ, McMurray JJV. Selecting patients for cardiac resynchronization therapy: electrical or mechanical dyssynchrony? Eur Heart J 2006; 27:1270-81. [PMID: 16527827 DOI: 10.1093/eurheartj/ehi826] [Citation(s) in RCA: 118] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Cardiac resynchronization therapy (CRT) markedly reduces morbidity and mortality in patients with heart failure and prolonged QRS duration. Landmark trials have included over 4000 patients based on their electrocardiogram. A few small, observational, non-randomized, single centre studies of short duration have suggested that echocardiographic measurement of mechanical dyssynchrony may better identify patients likely to benefit from CRT. We objectively review the meaning and measurement of electrical and mechanical dyssynchrony, the strengths and weaknesses of echocardiographic indices of dyssynchrony, and the controversial issue of predicting response to treatment. We conclude that proposals to alter current guidelines for patient selection, and include echocardiography, are misguided. Echocardiographic assessment will only become credible and applicable to clinical practice once used to select patients for large prospective randomized trials which show an improvement in clinical outcome.
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Affiliation(s)
- Nathaniel M Hawkins
- Department of Cardiology, Stobhill Hospital, Balornock Road, Springburn, Glasgow G21 3UW, UK.
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25
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Bax JJ, Abraham T, Barold SS, Breithardt OA, Fung JWH, Garrigue S, Gorcsan J, Hayes DL, Kass DA, Knuuti J, Leclercq C, Linde C, Mark DB, Monaghan MJ, Nihoyannopoulos P, Schalij MJ, Stellbrink C, Yu CM. Cardiac resynchronization therapy: Part 1--issues before device implantation. J Am Coll Cardiol 2006; 46:2153-67. [PMID: 16360042 DOI: 10.1016/j.jacc.2005.09.019] [Citation(s) in RCA: 364] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2005] [Revised: 09/19/2005] [Accepted: 09/19/2005] [Indexed: 11/19/2022]
Abstract
Cardiac resynchronization therapy (CRT) has been used extensively over the last years in the therapeutic management of patients with end-stage heart failure. Data from 4,017 patients have been published in eight large, randomized trials on CRT. Improvement in clinical end points (symptoms, exercise capacity, quality of life) and echocardiographic end points (systolic function, left ventricular size, mitral regurgitation) have been reported after CRT, with a reduction in hospitalizations for decompensated heart failure and an improvement in survival. However, individual results vary, and 20% to 30% of patients do not respond to CRT. At present, the selection criteria include severe heart failure (New York Heart Association functional class III or IV), left ventricular ejection fraction <35%, and wide QRS complex (>120 ms). Assessment of inter- and particularly intraventricular dyssynchrony as provided by echocardiography (predominantly tissue Doppler imaging techniques) may allow improved identification of potential responders to CRT. In this review a summary of the clinical and echocardiographic results of the large, randomized trials is provided, followed by an extensive overview on the currently available echocardiographic techniques for assessment of LV dyssynchrony. In addition, the value of LV scar tissue and venous anatomy for the selection of potential candidates for CRT are discussed.
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Affiliation(s)
- Jeroen J Bax
- Department of Cardiology, Leiden University Medical Center, Leiden, The Netherlands.
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26
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Yu CM, Wing-Hong Fung J, Zhang Q, Sanderson JE. Understanding nonresponders of cardiac resynchronization therapy--current and future perspectives. J Cardiovasc Electrophysiol 2006; 16:1117-24. [PMID: 16191124 DOI: 10.1111/j.1540-8167.2005.40829.x] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
INTRODUCTION Cardiac resynchronization therapy (CRT) is now an established nonpharmacologic therapy for advanced heart failure with electromechanical delay. Despite compelling evidence of the benefits of CRT, one troubling issue is the lack of a favorable response in about one-third of patients. METHODS AND RESULTS Currently, there is no unifying definition of responders, and published data were based on acute hemodynamic changes, chronic left ventricular reverse remodeling, as well as the intermediate or long-term clinical response. The lack of improvement with CRT can be due to many factors including the placement of the left ventricular pacing lead in an inappropriate location, the absence of electrical conduction delay or mechanical dyssynchrony despite wide QRS complexes, and possibly failure to optimize the CRT settings after device implantation. In acute hemodynamic studies, placing the left ventricular leads at the free wall region has been suggested to generate the best pulse pressure and positive dp/dt. The degree of mechanical dyssynchrony has recently been assessed noninvasively in CRT patients by echocardiography and in particular by tissue Doppler imaging. These studies suggested that responders of left ventricular reverse remodeling or systolic function had more severe systolic dyssynchrony. However, further studies are needed to examine the clinical utility of these parameters when applied to the standardized anatomic or functional endpoints. Optimization of atrioventricular and interventricular pacing intervals may also reduce the number of nonresponders, though newer methods, especially interventricular pacing intervals, are still under clinical investigation. CONCLUSION With the adjunctive use of imaging technology, physicians are able to characterize the response to CRT objectively, and cardiac imaging is an important clinical tool for determining more precisely the presence and degree of mechanical dyssynchrony.
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Affiliation(s)
- Cheuk-Man Yu
- Division of Cardiology, Department of Medicine and Therapeutics, Prince of Wales Hospital, The Chinese University of Hong Kong.
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27
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Pham PP, Balaji S, Shen I, Ungerleider R, Li X, Sahn DJ. Impact of Conventional Versus Biventricular Pacing on Hemodynamics and Tissue Doppler Imaging Indexes of Resynchronization Postoperatively in Children With Congenital Heart Disease. J Am Coll Cardiol 2005; 46:2284-9. [PMID: 16360059 DOI: 10.1016/j.jacc.2005.08.036] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2005] [Revised: 08/16/2005] [Accepted: 08/19/2005] [Indexed: 11/29/2022]
Abstract
OBJECTIVES We sought to evaluate the effects of biventricular (BDOO) pacing compared with conventional (CDOO) atrioventricular (AV) sequential and atrial (AOO) pacing in children and infants in the early postoperative period after open heart surgery for congenital heart disease (CHD). BACKGROUND Biventricular pacing using right ventricular (RV) and left ventricular (LV) leads can improve hemodynamics in patients with CHD, but it is unclear whether this occurs in early postoperative children with CHD. METHODS Nineteen children (age, 5 days to 5.4 years; median, 5.5 months) with a definitive biventricular repair for CHD underwent AOO, CDOO, and BDOO pacing with temporary epicardial leads for 10 min each. The AV delay was 80% of the PR interval for the CDOO and BDOO modes. Lead placement was two right atrial, two RV, and one LV. Blood samples for cardiac index (arterial and venous) and tissue Doppler (TDI) traces were obtained in each pacing mode with a Vivid 7 BT04 digital ultrasound system (GE/VingMed, Horten, Norway) from an apical four-chamber view and analyzed with EchoPac software. RESULTS The QRS duration was significantly shorter for BDOO compared with CDOO, and the cardiac index was higher with BDOO compared with CDOO. Systemic blood pressure was not different between the three modes of pacing (AOO, CDOO, BDOO). The TDI-derived strain rate showed minimal dyssynchrony in AOO as seen by isovolumic tensing (IVT) and peak systolic contraction (PSC) timing differences between RV and LV. The CDOO worsened dyssynchrony with prolonged DeltaIVT and PSC. The BDOO showed improved synchrony as seen by DeltaIVT and PSC. CONCLUSIONS The TDI-derived strain rate showed worsened ventricular dyssynchrony with CDOO and improvement with BDOO. Cardiac index and QRS duration were improved by BDOO compared with CDOO. This suggests that short-term pacing with BDOO may benefit children with CHD needing pacing in the postoperative period.
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MESH Headings
- Blood Pressure
- Cardiac Output
- Cardiac Pacing, Artificial/adverse effects
- Cardiac Pacing, Artificial/methods
- Cardiac Pacing, Artificial/standards
- Child, Preschool
- Echocardiography, Doppler
- Electrocardiography
- Female
- Heart Defects, Congenital/complications
- Heart Defects, Congenital/diagnosis
- Heart Defects, Congenital/physiopathology
- Heart Defects, Congenital/therapy
- Heart Ventricles
- Hemodynamics
- Humans
- Infant
- Infant, Newborn
- Male
- Treatment Outcome
- Ventricular Dysfunction/etiology
- Ventricular Dysfunction/physiopathology
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Affiliation(s)
- Phat P Pham
- Oregon Health and Science University, Portland, Oregon, USA
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28
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Cavusoglu Y, Ata N, Timuralp B, Birdane A, Gorenek B, Unalir A. Visualization of the site of the onset of ventricular depolarization by acceleration mode Tissue Doppler imaging technique. Int J Cardiovasc Imaging 2005; 22:171-6. [PMID: 16237498 DOI: 10.1007/s10554-005-9003-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2005] [Accepted: 06/01/2005] [Indexed: 10/25/2022]
Abstract
Tissue Doppler imaging (TDI) is a relatively new echocardiographic technique that shows regional myocardial wall velocities. The aim of this study was to evaluate the potential value of acceleration mode TDI technique for the visualization of the origin of ventricular activation site using the model of right ventricular pacing. Twenty-seven patients with implanted permanent pacemakers were studied by acceleration mode TDI, 4 of these patients were pacemaker dependent. Parasternal and apical chamber views were recorded on video tape by using acceleration mode TDI technique during sinus rhythm with preserved atrioventricular conduction in 23 subjects who were not pacemaker-dependent, and also during right ventricular apical pacing in VVI mode in 27 subjects in whom pacing lower rate was increased if necessary. Fifty images recorded during sinus and pacing rhythm in cineloop were examined by two independent observers who were unaware of the rhythm patterns and by the same observer on two different occasions for localizing the site of onset of ventricular acceleration. The origin of ventricular activation during sinus rhythm started at basal septal part of the ventricle and during pacing started at apical part of the ventricle was considered as correct localizations. The origin of ventricular depolarization was correctly localized for 46 of 50 images (92%) and 44 of 50 images (88%) by the first and the second observers, respectively. Concordant results between observers appeared in 48 of 50 (96%) of images. The diagnostic accuracy of the concordant results was 44 of 48 (91.6%) images. The kappa for interobserver variability was 0.77 (p<0.001), and for intraobserver variability was 0.64 (p<0.001) and 0.63 (p<0.001) for the first and the second observers, respectively. These results suggest that acceleration mode TDI can be used to detect the initial ventricular excited position and seems to have a potential value for localizing of the origin of normal or abnormal myocardial depolarization.
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29
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Gassis S, León AR. Cardiac Resynchronization Therapy: Strategies for Device Programming, Troubleshooting and Follow-Up. J Interv Card Electrophysiol 2005; 13:209-22. [PMID: 16177848 DOI: 10.1007/s10840-005-3247-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2005] [Accepted: 06/21/2005] [Indexed: 05/04/2023]
Abstract
Cardiac resynchronization therapy (CRT) improves symptoms, exercise performance, ventricular function, and survival in patients with left ventricular dysfunction, prolonged QRS, and drug-refractory moderate to severe CHF. The growing application of CRT has created a large number of patients with complicated devices that need follow-up care from general practitioners, cardiologists, heart failure specialists and electro-physiologists. Optimal care of the CRT patient includes recognition and management of peri-implantation complications, optimal programming of atrio-ventricular and sequential ventricular timing, and troubleshooting device-related problems during long-term follow-up. A basic awareness of fundamental device features, the techniques to maximize the response to CRT, and an understanding of stored device data to track the response to therapy provide clinicians the ability to maximize clinical outcomes in the CHF patient. As evolving technology continues to increase the complexity of device therapies, clinicians must understand these therapies in order to properly treat heart failure patients. This work summarizes many of the issues involving early complications of CRT device implant, the strategies to optimize device function, and suggests a scheme for follow-up care of patients with CRT devices.
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Affiliation(s)
- Safwat Gassis
- Clinical Cardiac Electrophysiology, The Carlyle Fraser Heart Center, Division of Cardiology, Emory University School of Medicine, Atlanta, GA 30308, USA
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30
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Knebel F, Reibis RK, Bondke HJ, Witte J, Walde T, Eddicks S, Baumann G, Borges AC. Tissue Doppler echocardiography and biventricular pacing in heart failure: patient selection, procedural guidance, follow-up, quantification of success. Cardiovasc Ultrasound 2004; 2:17. [PMID: 15369591 PMCID: PMC521694 DOI: 10.1186/1476-7120-2-17] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2004] [Accepted: 09/15/2004] [Indexed: 01/26/2023] Open
Abstract
Asynchronous myocardial contraction in heart failure is associated with poor prognosis. Resynchronization can be achieved by biventricular pacing (BVP), which leads to clinical improvement and reverse remodeling. However, there is a substantial subset of patients with wide QRS complexes in the electrocardiogram that does not improve despite BVP. QRS width does not predict benefit of BVP and only correlates weakly with echocardiographically determined myocardial asynchrony. Determination of asynchrony by Tissue Doppler echocardiography seems to be the best predictor for improvement after BVP, although no consensus on the optimal method to assess asynchrony has been achieved yet. Our own preliminary results show the usefulness of Tissue Doppler Imaging and Tissue Synchronization Imaging to document acute and sustained improvement after BVP. To date, all studies evaluating Tissue Doppler in BVP were performed retrospectively and no prospective studies with patient selection for BVP according to echocardiographic criteria of asynchrony were published yet. We believe that these new echocardiographic tools will help to prospectively select patients for BVP, help to guide implantation and to optimize device programming.
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Affiliation(s)
- Fabian Knebel
- Charité Campus Mitte – University Medicine Berlin, Medical Clinic for Cardiology, Angiology, Pneumology, 10098 Berlin, Germany
| | - Rona Katharina Reibis
- Klinik am See, Department of Cardiology, Rehabilitation Center of Cardiovascular Diseases, Seebad 84, 15562 Rüdersdorf (Berlin), Germany
| | - Hans-Jürgen Bondke
- Charité Campus Mitte – University Medicine Berlin, Medical Clinic for Cardiology, Angiology, Pneumology, 10098 Berlin, Germany
| | - Joachim Witte
- Charité Campus Mitte – University Medicine Berlin, Medical Clinic for Cardiology, Angiology, Pneumology, 10098 Berlin, Germany
| | - Torsten Walde
- Charité Campus Mitte – University Medicine Berlin, Medical Clinic for Cardiology, Angiology, Pneumology, 10098 Berlin, Germany
| | - Stephan Eddicks
- Charité Campus Mitte – University Medicine Berlin, Medical Clinic for Cardiology, Angiology, Pneumology, 10098 Berlin, Germany
| | - Gert Baumann
- Charité Campus Mitte – University Medicine Berlin, Medical Clinic for Cardiology, Angiology, Pneumology, 10098 Berlin, Germany
| | - Adrian Constantin Borges
- Charité Campus Mitte – University Medicine Berlin, Medical Clinic for Cardiology, Angiology, Pneumology, 10098 Berlin, Germany
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