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Gold MR, Birgersdotter-Green U, Singh JP, Ellenbogen KA, Yu Y, Meyer TE, Seth M, Tchou PJ. The relationship between ventricular electrical delay and left ventricular remodelling with cardiac resynchronization therapy. Eur Heart J 2011; 32:2516-24. [PMID: 21875862 PMCID: PMC3195261 DOI: 10.1093/eurheartj/ehr329] [Citation(s) in RCA: 259] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Aims The aim of the present study was to evaluate the relationship between left ventricular (LV) electrical delay, as measured by the QLV interval, and outcomes in a prospectively designed substudy of the SMART-AV Trial. Methods and results This was a multicentre study of patients with advanced heart failure undergoing cardiac resynchronization therapy (CRT) defibrillator implantation. In 426 subjects, QLV was measured as the interval from the onset of the QRS from the surface ECG to the first large peak of the LV electrogram. Left ventricular volumes were measured by echocardiography at baseline and after 6 months of CRT by a blinded core laboratory. Quality of life (QOL) was assessed by a standardized questionnaire. When separated by quartiles based on QLV duration, reverse remodelling response rates (>15% reduction in LV end systolic volume) increased progressively from 38.7 to 68.4% and QOL response rate (>10 points reduction) increased from 50 to 72%. Patients in the highest quartile of QLV had a 3.21-fold increase (1.58–6.50, P = 0.001) in their odds of a reverse remodelling response after correcting for QRS duration, bundle branch block type, and clinical characteristics by multivariate logistic regression analysis. Conclusion Electrical dyssynchrony, as measured by QLV, was strongly and independently associated with reverse remodelling and QOL with CRT. Acute measurements of QLV may be useful to guide LV lead placement.
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Affiliation(s)
- Michael R Gold
- Medical University of South Carolina, 25 Courtenay Drive, ART 7031, Charleston, SC 29425-5920, USA.
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Kindermann M, Mahfoud F, Ukena C, Fröhlig G. [Cardiac resynchronization therapy: preoperative screening. How can we reliably predict response to CRT?]. Herzschrittmacherther Elektrophysiol 2011; 20:131-42. [PMID: 19672672 DOI: 10.1007/s00399-009-0053-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Cardiac resynchronization therapy (CRT) is an established therapy for patients with advanced heart failure, depressed left ventricular function, and wide QRS complex. However, about 30 to 45% of patients do not respond to CRT. Assuming that the main therapeutic action of CRT is the correction of dyssynchronous myocardial contraction, a plethora of echocardiographic dyssynchrony parameters have been proposed to improve the prediction of response to CRT. However, one multicenter study has recently questioned the utility of any of these indexes. This review delineates the various causes of non-response to CRT, explains the different levels and mechanisms of dyssynchrony and gives a critical overview of currently available echocardiographic techniques for assessment of dyssynchrony. Based upon a discussion of the evidence coming from randomized multicenter studies and against the background of national and international cardiac societies' guideline recommendations on CRT, a rational basis for the evaluation of patients for CRT is proposed.
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Affiliation(s)
- M Kindermann
- Klinik für Innere Medizin III, Kardiologie, Angiologie, Internistische Intensivmedizin, Universitätsklinikum des Saarlandes, Kirrberger Str. 100, 66421, Homburg/Saar, Deutschland.
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Pires LA, Ghio S, Chung ES, Tavazzi L, Abraham WT, Gerritse B. Relationship Between Acute Improvement in Left Ventricular Function to 6-Month Outcomes After Cardiac Resynchronization Therapy in Patients With Chronic Heart Failure. ACTA ACUST UNITED AC 2011; 17:65-70. [DOI: 10.1111/j.1751-7133.2010.00207.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Ishikawa T. Limitations and Problems of Assessment of Mechanical Dyssynchrony in Determining Cardiac Resynchronization Therapy Indication - Is Assessment of Mechanical Dyssynchrony Necessary in Determining CRT Indication? (Con) -. Circ J 2011; 75:465-71. [DOI: 10.1253/circj.cj-10-1252] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Dong K, Shen WK, Powell BD, Dong YX, Rea RF, Friedman PA, Hodge DO, Wiste HJ, Webster T, Hayes DL, Cha YM. Atrioventricular nodal ablation predicts survival benefit in patients with atrial fibrillation receiving cardiac resynchronization therapy. Heart Rhythm 2010; 7:1240-5. [DOI: 10.1016/j.hrthm.2010.02.011] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2009] [Accepted: 02/05/2010] [Indexed: 10/19/2022]
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Wang DY, Richmond ME, Quinn TA, Mirani AJ, Rusanov A, Yalamanchi V, Weinberg AD, Cabreriza SE, Spotnitz HM. Optimized temporary biventricular pacing acutely improves intraoperative cardiac output after weaning from cardiopulmonary bypass: a substudy of a randomized clinical trial. J Thorac Cardiovasc Surg 2010; 141:1002-8, 1008.e1. [PMID: 20800242 DOI: 10.1016/j.jtcvs.2010.07.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2010] [Revised: 06/24/2010] [Accepted: 07/06/2010] [Indexed: 10/19/2022]
Abstract
OBJECTIVE Permanent biventricular pacing benefits patients with heart failure and interventricular conduction delay, but the importance of pacing with and without optimization in patients at risk of low cardiac output after cardiac surgery is unknown. We hypothesized that pacing parameters independently affect cardiac output. Accordingly, we analyzed aortic flow measured with an electromagnetic flowmeter in patients at risk of low cardiac output during an ongoing randomized clinical trial of biventricular pacing (n = 11) versus standard of care (n = 9). METHODS A substudy was conducted in all 20 patients in both groups with stable pacing after coronary artery bypass grafting, valve surgery, or both. Ejection fraction averaged 33% ± 15%, and QRS duration was 116 ± 19 ms. Effects were measured within 1 hour of the conclusion of cardiopulmonary bypass. Atrioventricular delay (7 settings) and interventricular delay (9 settings) were optimized in random sequence. RESULTS Optimization of atrioventricular delay (171 ± 8 ms) at an interventricular delay of 0 ms increased flow by 14% versus the worst setting (111 ± 11 ms, P < .001) and 7% versus nominal atrioventricular delay (120 ms, P < .001). Interventricular delay optimization increased flow 10% versus the worst setting (P < .001) and 5% versus nominal interventricular delay (0 ms, P < .001). Optimized pacing increased cardiac output 13% versus atrial pacing at matched heart rate (5.5 ± 0.5 vs 4.9 ± 0.6 L/min, P = .003) and 10% versus sinus rhythm (5.0 ± 0.6 L/min, P = .019). CONCLUSIONS Temporary biventricular pacing increases intraoperative cardiac output in patients with left ventricular dysfunction undergoing cardiac surgery. Atrioventricular and interventricular delay optimization maximizes this benefit.
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Affiliation(s)
- Daniel Y Wang
- Department of Medicine, Columbia University, New York, NY, USA
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107
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Bocchiardo M, Meyer zu Vilsendorf D, Militello C, Lippert M, Czygan G, Schauerte P, Gaita F, Stellbrink C. Resynchronization therapy optimization by intracardiac impedance. Europace 2010; 12:1589-95. [DOI: 10.1093/europace/euq273] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Porciani MC, Cappelli F, Perrotta L, Chiostri M, Rao CM, Pieragnoli P, Ricciardi G, Michelucci A, Jelic S, Padeletti L. Has Mechanical Dyssynchrony Still a Role in Predicting Cardiac Resynchronization Therapy Response? Echocardiography 2010; 27:831-8. [DOI: 10.1111/j.1540-8175.2009.01133.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
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Dizon JM, Quinn TA, Cabreriza SE, Wang D, Spotnitz HM, Hickey K, Garan H. Real-time stroke volume measurements for the optimization of cardiac resynchronization therapy parameters. Europace 2010; 12:1270-4. [PMID: 20525728 DOI: 10.1093/europace/euq175] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
AIMS We investigated the utility of real-time stroke volume (SV) monitoring via the arterial pulse power technique to optimize cardiac resynchronization therapy (CRT) parameters at implant and prospectively evaluated the clinical and echocardiographic results. METHODS AND RESULTS Fifteen patients with ischaemic or non-ischaemic dilated cardiomyopathy, sinus rhythm, Class III congestive heart failure, and QRS >150 ms underwent baseline 2D echocardiogram (echo), 6 min walk distance, and quality of life (QOL) questionnaire within 1 week of implant. Following implant, 0.3 mmol lithium chloride was injected to calibrate SV via dilution curve. Atrioventricular (AV) delay (90, 120, 200 ms, baseline: atrial pacing only) and V-V delay (-80 to 80 ms in 20 ms increments) were varied every 60 s. The radial artery pulse power autocorrelation method (PulseCO algorithm, LiDCO, Ltd.) was used to monitor SV on a beat-to-beat basis (LiDCO, Ltd.). Optimal parameters were programmed and echo, 6 min walk, and QOL were repeated at 6-8 weeks post-implant. Nine patients had >5% increase in SV after optimization (Group A). Six patients had <5% improvement in SV (Group B). Compared with Group B, Group A had significant improvements in left ventricular ejection fraction (LVEF) (11.0 +/- 8.5 vs. 0.8 +/- 2.0%) and decrease in left ventricular end-diastolic dimension (LVEDD) (-0.6 +/- 0.4 vs. -0.2 +/- 0.2 cm) and 6 min walk (346 +/- 226 vs. 32 +/-271 ft, P < or = 0.05). Group A patients also tended to have greater improvement in the septal-to-posterior wall motion delay on M-mode echo (P = 0.07). CONCLUSION Real-time SV measurements can be used to optimize CRT at the time of implant. Improvement in SV correlates with improvement in LVEF, LVEDD, and 6 min walk, and improvement in echocardiographic dyssynchrony.
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Affiliation(s)
- José M Dizon
- Division of Cardiology, Department of Medicine, Columbia University Medical Center, New York, NY 10032, USA.
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Harel F, Finnerty V, Grégoire J, Thibault B, Marcotte F, Ugolini P, Khairy P. Gated blood-pool SPECT versus cardiac magnetic resonance imaging for the assessment of left ventricular volumes and ejection fraction. J Nucl Cardiol 2010; 17:427-34. [PMID: 20151236 DOI: 10.1007/s12350-010-9195-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2009] [Accepted: 01/28/2010] [Indexed: 10/19/2022]
Abstract
BACKGROUND We evaluated the accuracy of planar radionuclide angiography and different count-based and space-based electrocardiogram (ECG)-gated blood-pool single-photon emission computed tomography (GBPS) algorithms for assessment of left ventricular end-diastolic volume (LVEDV), end-systolic volume (LVESV), and ejection fraction (LVEF) compared with the gold standard of cardiac magnetic resonance imaging (cMRI). The goal is to assess the accuracy of a recently developed GBPS algorithm. METHODS AND RESULTS Subjects had planar, GBPS, and cMRI sequentially. Datasets were processed by QBS software (Cedar-Sinai) and by MHI software (Montreal Heart Institute). Space-based approaches were used to compute LVEDV, LVESV, and LVEF. Count-based techniques were also used to assess LVEF. All results were compared to cMRI. Fifty-five patients (85% male; mean age 63 +/- 9 years) completed the study. LVEFs and their correlations to cMRI values were 43 +/- 12% (r = .82), 39 +/- 14% (r = .82), and 39 +/- 13% for MHI(space), QBS(space), and cMRI methodologies, respectively. LVEF by count-based methods also demonstrated good correlation to LVEF provided by cMRI (42 +/- 13%, r = .88 for MHI(count) and 46 +/- 15%, r = .84 for QBS(count)). Strong correlations were obtained for LVEDV (r = .96 for MHI and r = .92 for QBS) and for LVESV (.97 for MHI and r = .94 for QBS). CONCLUSIONS All Gated blood-pool SPECT algorithms had significant variation in estimating LVEF. Nevertheless our software provides good estimates of LV volumes and LVEF. Such software may, therefore, be applied to assess LV morphology and function.
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Affiliation(s)
- François Harel
- Department of Nuclear Medicine, Montreal Heart Institute and University of Montréal, 5000 Belanger Street, Montreal, QC H1T 1C8, Canada.
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Liang YJ, Zhang Q, Fung JWH, Chan JYS, Yip GWK, Lam YY, Yu CM. Impact of reduction in early- and late-systolic functional mitral regurgitation on reverse remodelling after cardiac resynchronization therapy. Eur Heart J 2010; 31:2359-68. [DOI: 10.1093/eurheartj/ehq134] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
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Gelsomino S, Lorusso R, De Cicco G, Billè G, Caciolli S, Rostagno C, Capecchi I, Chioccioli M, Stefàno P, Gensini GF. Does preoperative tethering symmetry affect left ventricular reverse remodeling after restrictive annuloplasty? Int J Cardiol 2010; 141:182-91. [DOI: 10.1016/j.ijcard.2008.11.190] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2008] [Accepted: 11/29/2008] [Indexed: 11/16/2022]
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Fornwalt BK, Sprague WW, BeDell P, Suever JD, Gerritse B, Merlino JD, Fyfe DA, León AR, Oshinski JN. Agreement is poor among current criteria used to define response to cardiac resynchronization therapy. Circulation 2010; 121:1985-91. [PMID: 20421518 DOI: 10.1161/circulationaha.109.910778] [Citation(s) in RCA: 229] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
BACKGROUND Numerous criteria believed to define a positive response to cardiac resynchronization therapy have been used in the literature. No study has investigated agreement among these response criteria. We hypothesized that the agreement among the various response criteria would be poor. METHODS AND RESULTS A literature search was conducted with the keywords "cardiac resynchronization" and "response." The 50 publications with the most citations were reviewed. After the exclusion of editorials and reviews, 17 different primary response criteria were identified from 26 relevant articles. The agreement among 15 of these 17 response criteria was assessed in 426 patients from the Predictors of Response to Cardiac Resynchronization Therapy (PROSPECT) study with Cohen's kappa-coefficient (2 response criteria were not calculable from PROSPECT data). The overall response rate ranged from 32% to 91% for the 15 response criteria. Ninety-nine percent of patients showed a positive response according to at least 1 of the 15 criteria, whereas 94% were classified as a nonresponder by at least 1 criterion. kappa-Values were calculated for all 105 possible comparisons among the 15 response criteria and classified into standard ranges: Poor agreement (kappa< or =0.4), moderate agreement (0.4<kappa<0.75), and strong agreement (kappa> or =0.75). Seventy-five percent of the comparisons showed poor agreement, 21% showed moderate agreement, and only 4% showed strong agreement. CONCLUSIONS The 26 most-cited publications on predicting response to cardiac resynchronization therapy define response using 17 different criteria. Agreement between different methods to define response to cardiac resynchronization therapy is poor 75% of the time and strong only 4% of the time, which severely limits the ability to generalize results over multiple studies.
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Affiliation(s)
- Brandon K Fornwalt
- Emory University School of Medicine, Department of Radiology, Atlanta, GA 30322, USA.
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Crossley GH, Exner D, Mead RH, Sorrentino RA, Hokanson R, Li S, Adler S. Chronic performance of an active fixation coronary sinus lead. Heart Rhythm 2010; 7:472-8. [DOI: 10.1016/j.hrthm.2010.01.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2009] [Accepted: 01/03/2010] [Indexed: 10/20/2022]
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115
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Porciani CM, Lilli A, Cappelli F, Pappone A, Perini AP, Pieragnoli P, Ricciardi G, Rao CM, Prinzen FW, Michelucci A, Padeletti L. Echo/Doppler-derived time intervals are able to predict left ventricular reverse remodeling after cardiac resynchronization therapy. J Cardiovasc Med (Hagerstown) 2010; 11:157-63. [PMID: 19841591 DOI: 10.2459/jcm.0b013e328332e938] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
AIM We evaluated the predictive value of echo/Doppler derived indices, which reflect the duration of the isovolumic phases of the cardiac cycle, in identifying cardiac resynchronization therapy (CRT) responders. METHODS AND RESULTS In 105 patients before and 6 months after CRT the following echo/Doppler parameters were evaluated: myocardial performance index (MPI) as the sum of isovolumic contraction time (IVCT) and isovolumic relaxation time (IVRT) divided by ejection time; total isovolumic time (t-IVT) as the sum of IVCT and IVRT divided by the RR interval; and standard deviation of the time to systolic peak velocity (Ts-SD) as asynchrony index. After 6 months, patients were defined responders according to 15% left ventricle (LV) end-systolic volume reduction or more. At baseline, responders (53.3%) had higher t-IVT and MPI than nonresponders (0.30 +/- 0.06 versus 0.22 +/- 0.05, P < 0.0001 and 1.01 +/- 0.27 versus 0.73 +/- 0.19, P < 0.0001, respectively). Receiving operating characteristic curve analysis showed that both t-IVT (80.3% sensitivity and 83.7% specificity, cut-off = 0.263) and MPI (78.6% sensitivity and 81.6% specificity, cut-off = 0.84) could predict CRT response. Baseline t-IVT correlated well to end-systolic volume reduction (r = -0.56, P < 0.00001). CONCLUSION Echo/Doppler derived indices, describing physiologic abnormalities of the isovolumic contraction and relaxation phase, are able to predict CRT-induced reverse remodeling.
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Sassone B, Gabrieli L, Saccà S, Boggian G, Fusco A, Pratola C, Bacchi-Reggiani ML, Padeletti L, Barold SS. Value of right ventricular-left ventricular interlead electrical delay to predict reverse remodelling in cardiac resynchronization therapy: the INTER-V pilot study. Europace 2010; 12:78-83. [PMID: 19897503 DOI: 10.1093/europace/eup347] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
AIMS Few studies have systematically evaluated the value of intra-procedural parameters in predicting response to cardiac resynchronization therapy (CRT). We investigated whether intracardiac (electrogram) measurements of electrical delays between the positioned right ventricular (RV) and left ventricular (LV) leads at implantation could predict the mid-term CRT response. METHODS AND RESULTS Fifty-two patients underwent CRT implantation according to standard techniques and clinical indications. The RV-LV interlead electrical delay measured during spontaneous rhythm and the difference between the pacing-induced (Deltap) RV-LV interlead electrical delays measured during RV and LV pacing were defined intraoperatively using the electrical depolarizations registered at the ventricular leads on the device programmer. At 6 months, a reduction of LV end-systolic volume > or = 15% was used to define CRT responders. Responders (62%), when compared with non-responders, showed a higher proportion of ischaemic aetiology (P = 0.007) and a lower value of DeltapRV-LV interlead electrical delay (22.1 +/- 18.4 vs. 46.3 +/- 15.0 ms, P = 0.0001). At multivariate analysis, the DeltapRV-LV interlead electrical delay was the only independent predictor of response to CRT (P = 0.001). For such a parameter, the receiving operating characteristic curve analysis identified a cut-off value of 42 ms corresponding with the highest accuracy: sensitivity 90.6%; specificity 70%; positive and negative predictive value 83% and 82%, respectively. Conversely, no difference was ascertained between responders and non-responders when RV-LV interlead electrical delay was measured during spontaneous rhythm (76.1 +/- 28.5 vs. 89.6 +/- 21.2, P = 0.078). CONCLUSION Intraprocedural measuring of paced RV-LV interlead electrical delay obtained during RV and LV pacing predicts mid-term CRT response.
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Affiliation(s)
- Biagio Sassone
- Department of Cardiology, Bentivoglio Hospital, Azienda USL di Bologna, Via Marconi, 35-40010 Bentivoglio, Bologna, Italy.
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Bocchiardo M, Meyer zu Vilsendorf D, Militello C, Lippert M, Czygan G, Gaita F, Schauerte P, Stellbrink C. Intracardiac impedance monitors stroke volume in resynchronization therapy patients. Europace 2010; 12:702-7. [DOI: 10.1093/europace/euq045] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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van Geldorp IE, Vernooy K, Delhaas T, Prins MH, Crijns HJ, Prinzen FW, Dijkman B. Beneficial effects of biventricular pacing in chronically right ventricular paced patients with mild cardiomyopathy. Europace 2009; 12:223-9. [DOI: 10.1093/europace/eup378] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Stein KM, Ellenbogen KA, Gold MR, Lemke B, Lozano IF, Mittal S, Spinale FG, Van Eyk JE, Waggoner AD, Meyer TE. SmartDelay determined AV optimization: a comparison of AV delay methods used in cardiac resynchronization therapy (SMART-AV): rationale and design. PACING AND CLINICAL ELECTROPHYSIOLOGY: PACE 2009; 33:54-63. [PMID: 19821938 DOI: 10.1111/j.1540-8159.2009.02581.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND The clinical benefit of cardiac resynchronization therapy (CRT) for patients with moderate-to-severely symptomatic heart failure, left ventricular systolic dysfunction, and ventricular conduction delay is established. However, some patients do not demonstrate clinical improvement following CRT. It is unclear whether systematic optimization of the programmed atrioventricular (AV) delay improves the rate of clinical response. METHODS SMART-AV is a randomized, multicenter, double-blinded, three-armed trial that will investigate the effects of optimizing AV delay timing in heart failure patients receiving CRT + defibrillator (CRT-D) therapy. A minimum of 950 patients will be randomized in a 1:1:1 ratio using randomly permuted blocks within each center programmed to either DDD or DDDR with a lower rate of 60. The study will include echocardiographic measurements of volumes and function [e.g., left ventricular end-systolic volume (LVESV)], biochemical measurements of plasma biomarker profiles, and functional measurements (e.g., 6-minute hall walk) in CRT-D patients who are enrolled and randomized to fixed AV delay (i.e., 120 ms), AV delay determined by electrogram-based SmartDelay, or an AV delay determined by echocardiography (i.e., mitral inflow). Patients will be evaluated prior to initiation of CRT, 3 and 6 months post-implant. The primary endpoint is the relative change in LVESV at 6 months between the groups. Patient enrollment commenced in May 2008 and the study is registered at clinicaltrials.gov. CONCLUSION SMART-AV is a randomized, clinical trial designed to evaluate three different methods of AV delay optimization to determine whether systematic AV optimization is beneficial for patients receiving CRT for 6 months post-implant.
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Affiliation(s)
- Kenneth M Stein
- Department of Medicine, Maurice & Corinne Greenberg Division of Cardiology, Weill Medical College of Cornell University, New York, New York, USA.
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Rüssel IK, Götte MJ, de Roest GJ, Marcus J, Tecelão SR, Allaart CP, de Cock CC, Heethaar RM, van Rossum AC. Loss of Opposite Left Ventricular Basal and Apical Rotation Predicts Acute Response to Cardiac Resynchronization Therapy and is Associated With Long-Term Reversed Remodeling. J Card Fail 2009; 15:717-25. [PMID: 19786261 DOI: 10.1016/j.cardfail.2009.04.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2008] [Revised: 03/02/2009] [Accepted: 04/13/2009] [Indexed: 11/27/2022]
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Nesser HJ, Winter S, Lang RM, Mor-Avi V. Echocardiographic techniques for the evaluation of left ventricular dyssynchrony. CURRENT CARDIOVASCULAR IMAGING REPORTS 2009. [DOI: 10.1007/s12410-009-0043-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Incremental prognostic value of combining left ventricular lead position and systolic dyssynchrony in predicting long-term survival after cardiac resynchronization therapy. Clin Sci (Lond) 2009; 117:397-404. [PMID: 19335338 DOI: 10.1042/cs20080580] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The efficacy of CRT (cardiac resynchronization therapy) can be affected by a number of factors; however, the prognostic significance of the LV (left ventricular) lead position has not been explored. The aim of the present study was to examine whether a PL (posterolateral) lead position has an additional value to systolic dyssynchrony in predicting a better survival after CRT. Patients (n=134) who received CRT were followed-up for 39±24 months. The LV lead position was determined by cine fluoroscopy, and baseline dyssynchrony was assessed by TDI (tissue Doppler imaging). The relationship between the LV lead position/dyssynchrony and mortality was compared using Kaplan–Meier curves, followed by Cox regression analysis. The all-cause and cardiovascular mortalities were 38 and 31% respectively. The presence of dyssynchrony and a PL lead position predicted a lower all-cause mortality (29 compared with 47%; log-rank χ2=5.38, P=0.02) and cardiovascular mortality (21 compared with 41%; log-rank χ2=6.75, P=0.009) than when absent. The all-cause mortality was as high as 62% when patients had neither dyssynchrony nor a PL lead position, but was reduced to 29% when both criteria were present, and was between 45 and 46% when only one criterion was present (χ2=6.79, P=0.01). The corresponding values for cardiovascular mortality were 62% when patients had neither dyssynchrony nor a PL lead position, 36–38% when patients had either dyssynchrony or a PL lead position, and 21% when patients had both criteria present (χ2=9.54, P=0.004). Combining dyssynchrony and a PL lead position independently predicted a lower all-cause morality {HR (hazard ratio), 0.496 [95% CI (confidence interval), 0.278–0.888]; P=0.018} and cardiovascular mortality [HR, 0.442 (95% CI, 0.232–0.844); P=0.013]. In conclusion, the placement of the LV lead at a PL position provides additional value to baseline dyssynchrony in predicting a lower all-cause and cardiovascular mortality during long-term follow-up after CRT.
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Kuppahally SS, Fowler MB, Vagelos R, Wang P, Al-Ahmad A, Paloma A, Liang D. Worsening of Left Ventricular End-Systolic Volume and Mitral Regurgitation without Increase in Left Ventricular Dyssynchrony on Acute Interruption of Cardiac Resynchronization Therapy. Echocardiography 2009; 26:759-65. [PMID: 19558521 DOI: 10.1111/j.1540-8175.2008.00887.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Tomaske M, Breithardt OA, Bauersfeld U. Preserved cardiac synchrony and function with single-site left ventricular epicardial pacing during mid-term follow-up in paediatric patients. Europace 2009; 11:1168-76. [DOI: 10.1093/europace/eup178] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Carluccio E, Biagioli P, Alunni G, Murrone A, Leonelli V, Pantano P, Vincenti G, Giombolini C, Ragni T, Reboldi G, Gentile F, Ambrosio G. Effect of revascularizing viable myocardium on left ventricular diastolic function in patients with ischaemic cardiomyopathy. Eur Heart J 2009; 30:1501-9. [DOI: 10.1093/eurheartj/ehp125] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Ghio S, Freemantle N, Scelsi L, Serio A, Magrini G, Pasotti M, Shankar A, Cleland JG, Tavazzi L. Long-term left ventricular reverse remodelling with cardiac resynchronization therapy: results from the CARE-HF trial. Eur J Heart Fail 2009; 11:480-8. [DOI: 10.1093/eurjhf/hfp034] [Citation(s) in RCA: 151] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Stefano Ghio
- Division of Cardiology; Fondazione IRCCS Policlinico S. Matteo, University Hospital; Piazzale Golgi 1 27100 Pavia Italy
| | - Nick Freemantle
- Division of Primary Care; Public and Occupational Health, University of Birmingham; UK
| | - Laura Scelsi
- Division of Cardiology; Fondazione IRCCS Policlinico S. Matteo, University Hospital; Piazzale Golgi 1 27100 Pavia Italy
| | - Alessandra Serio
- Division of Cardiology; Fondazione IRCCS Policlinico S. Matteo, University Hospital; Piazzale Golgi 1 27100 Pavia Italy
| | - Giulia Magrini
- Division of Cardiology; Fondazione IRCCS Policlinico S. Matteo, University Hospital; Piazzale Golgi 1 27100 Pavia Italy
| | - Michele Pasotti
- Division of Cardiology; Fondazione IRCCS Policlinico S. Matteo, University Hospital; Piazzale Golgi 1 27100 Pavia Italy
| | - Aparna Shankar
- Division of Primary Care; Public and Occupational Health, University of Birmingham; UK
| | | | - Luigi Tavazzi
- Division of Cardiology; Fondazione IRCCS Policlinico S. Matteo, University Hospital; Piazzale Golgi 1 27100 Pavia Italy
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Effect of cardiac resynchronization therapy on the incidence of electrical storm. Int J Cardiol 2009; 143:330-6. [PMID: 19359057 DOI: 10.1016/j.ijcard.2009.03.055] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2008] [Revised: 01/21/2009] [Accepted: 03/09/2009] [Indexed: 01/29/2023]
Abstract
BACKGROUND Hemodynamic improvement from biventricular pacing is well documented; however, its electrophysiologic effects have not been systematically studied. In this study, incidence and risk factors for electrical storm (ES) were investigated in 729 ICD and biventricular defibrillator (CRT-D) heart failure patients. METHODS 168 consecutive CRT-D and 561 ICD patients were retrospectively analyzed for the occurrence of VT/VF and predisposing factors. Electrical storm was defined as ventricular tachycardia or fibrillation ≥3 times during 24 h. Mean follow-up was 41 months. RESULTS In 168 CRT-D patients only one patient experienced electrical storm compared to 39 patients out of 561 ICD patients (0.6% vs. 7%, p<0.01). 33% of the patients with electrical storm died within one year. In the CRT-D group 81 patients (48%) developed VT or VF and received at least one appropriate therapy, compared to 281 patients (50%) in the ICD group. Mean ejection fraction was 21.7% in the CRT-D group and 34.7% (p<0.01) in the ICD group. Stratifying the patients according to primary or secondary prevention and ejection fraction demonstrated that VT/VF clusters were significantly associated with ICD indication for secondary prevention, previous myocardial infarction and LVEF<30%. CONCLUSION The development of electrical storm is accompanied with a highly increased mortality risk even if an ICD/CRT-D is implanted. In CRT-D patients electrical storm is much less common than in ICD patients. Secondary prevention and ejection fraction<30% are predictors of electrical storm. Beside hemodynamic improvements cardiac resynchronization therapy may reduce the arrhythmia burden in heart failure patients.
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Vieira MLC, Cury AF, Naccarato G, Oliveira WA, Mônaco CG, Rodrigues ACT, Cordovil A, Tavares GMP, Lira Filho EB, Pfeferman A, Fischer CH, Morhy SS. Analysis of left ventricular regional dyssynchrony: comparison between real time 3D echocardiography and tissue Doppler imaging. Echocardiography 2009; 26:675-83. [PMID: 19392841 DOI: 10.1111/j.1540-8175.2008.00856.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND There is a paucity of information concerning left ventricular (LV) dyssynchrony assessment by real time three-dimensional (3D) echocardiography (RT3DE) versus tissue Doppler imaging (TDI). AIMS To compare RT3DE and TDI LV dyssynchrony assessment. METHODS A prospective study of 92 individuals (56 men, age 47 +/- 10 years), 32 with dilated cardiomyopathy (CMP), and 60 healthy individuals. By RT3DE, we measured the LV% dyssynchrony index (DI) of 6, 12, and 16 segments (SDI). By pulsed-wave TDI, we measured the QS electromechanical interval in the basal segments of the mitral valve annulus of the septum, the lateral, anterior and inferior walls, and the TDI% DI. RESULTS In the normal group, the 3D DI was 1.1 +/- 0.8%, 1.4 +/- 1.3%, 1.8 +/- 1.7%, for 6 segments, 12 segments, and SDI, respectively. The correlation coefficient (Pearson's r) for the TDI DI and SDI was r = 0.2381 (P = 0.0470). In CMP group, the 3D DI was 4.6 +/- 5.4%, 7.9 +/- 7.1%, 11.1 +/- 7.1%, for 6 segments, 12 segments, and SDI, respectively. The correlation coefficient for TDI DI and SDI was r = 0.7838 (P < 0.0001). CONCLUSIONS We observed a good correlation between RT3DE and tissue Doppler LV dyssynchrony assessment in patients with advanced heart failure.
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Affiliation(s)
- Marcelo L C Vieira
- Sector of Echocardiography, Hospital Israelita Albert Einstein, São Paulo, Brazil.
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Insights from a cardiac resynchronization optimization clinic as part of a heart failure disease management program. J Am Coll Cardiol 2009; 53:765-73. [PMID: 19245967 DOI: 10.1016/j.jacc.2008.11.024] [Citation(s) in RCA: 341] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2008] [Revised: 11/10/2008] [Accepted: 11/12/2008] [Indexed: 12/15/2022]
Abstract
OBJECTIVES Our aim was to determine the feasibility and value of a protocol-driven approach to patients with cardiac resynchronization therapy (CRT) who did not exhibit a positive response long after implant. BACKGROUND Up to one-third of patients with advanced heart failure do not exhibit a positive response to CRT. METHODS A total of 75 consecutive ambulatory patients with persistent advanced heart failure symptoms and/or adverse reverse remodeling and CRT implanted >6 months underwent a comprehensive protocol-driven evaluation to determine the potential reasons for a suboptimal response. Recommendations were made to maximize the potential of CRT, and adverse events were documented. RESULTS All patients (mean left ventricular [LV] ejection fraction 23 +/- 9%, LV end-diastolic volume 275 +/- 127 ml) underwent evaluation. Eighty-eight percent of patients had significantly better echocardiographic indexes of LV filling and LV ejection with optimal setting of their CRT compared with a temporary VVI back-up setting. Most patients had identifiable reasons for suboptimal response, including inadequate device settings (47%), suboptimal medical treatment (32%), arrhythmias (32%), inappropriate lead position (21%), or lack of baseline dyssynchrony (9%). Multidisciplinary recommendations led to changes in device settings and/or other therapy modifications in 74% of patients and were associated with fewer adverse events (13% vs. 50%, odds ratio: 0.2 [95% confidence interval: 0.07 to 0.56], p = 0.002) compared with those in which no recommendation could be made. CONCLUSIONS Routine protocol-driven approach to evaluate ambulatory CRT patients who did not exhibit a positive response is feasible, and changes in device settings and/or other therapies after multidisciplinary evaluation may be associated with fewer adverse events.
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Abstract
Secondary mitral regurgitation (MR) is frequent in patients with severely depressed left ventricular function. It increases mortality, and decreases exercise capacity. Its main mechanisms are multifactorial, related to apical and outward displacement of the papillary muscles, secondary to an enlarged and a more spherical left ventricle, causing increased subvalvar traction; mitral annular dilatation; and poor contraction of the left ventricle, with a slowed rate of rise of intraventricular pressure and slow closure of the leaflets. Since mechanical dyssynchrony is a major contributor factor to secondary MR, cardiac resynchronization therapy (CRT) could be considered as an alternative therapeutic option for MR, alone or in combination with surgical correction. Effects of CRT on secondary MR are acute and long-term, due to the reverse remodeling of the left ventricle. CRT reduces systolic MR by 30-40%, both at rest and during exercise, and abolishes diastolic MR, by increase of the closing forces and decrease of the tethering forces, acting on the mitral valve; decrease of the mitral annular dilatation represents a minor mechanism. Patients more likely to benefit should have moderate-to-severe MR (but not too severe), of nonischemic etiology, and high interpapillary muscles dyssynchrony. Effects are similar in patients with sinus rhythm and in patients with atrial fibrillation, and in patients with broad and narrow QRS complexes, provided that they have similar extent of dyssynchrony. Biventricular mode is the pacing modality of choice.
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Affiliation(s)
- Dragos Vinereanu
- Carol Davila University of Medicine and Pharmacy, Bucharest, Romania.
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Mullens W, Verga T, Grimm RA, Starling RC, Wilkoff BL, Tang WW. Persistent Hemodynamic Benefits of Cardiac Resynchronization Therapy With Disease Progression in Advanced Heart Failure. J Am Coll Cardiol 2009; 53:600-607. [DOI: 10.1016/j.jacc.2008.08.079] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2008] [Revised: 08/29/2008] [Accepted: 08/31/2008] [Indexed: 01/10/2023]
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Ascione L, Iengo R, Accadia M, Rumolo S, Celentano E, D'Andrea A, De Michele M, Muto C, Carreras G, Maglione M, Tuccillo B, Roelandt J. A radial global dyssynchrony index as predictor of left ventricular reverse remodeling after cardiac resynchronization therapy. PACING AND CLINICAL ELECTROPHYSIOLOGY: PACE 2008; 31:819-27. [PMID: 18684278 DOI: 10.1111/j.1540-8159.2008.01096.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Cardiac mechanical efficiency requires that opposing left ventricular regions are coupled both in shortening and lengthening during the same phase of cardiac cycle. Aim of this study was to evaluate whether global measures of mechanical dyssynchrony are able to predict reverse remodeling of the left ventricle in patients receiving cardiac resynchronization therapy (CRT). METHODS Sixty-two patients underwent a clinical examination, including New York Heart Association class evaluation and 6-minute walking distance and both echocardiographic study before and 6 months after CRT. Intraventricular dyssynchrony was evaluated by two-dimensional strain echocardiography, measuring the amount of uncoordinated contraction and relaxation between septum and free wall for both longitudinal and radial function and was presented as the longitudinal global dyssynchrony index (LGDI) and the radial global dyssynchrony index (RGDI). Reverse remodeling was defined by a left ventricular end systolic volume reduction >or= 15%. RESULTS After CRT 39 patients showed reverse remodeling. In this group, RGDI (0.74 +/- 0.26 vs 0.32 +/- 0.30; P = 0.0001) and LGDI (0.52 +/- 0.28 vs 0.30 +/- 0.24; P = 0.002) were significantly higher than in nonresponders. A receiver-operating characteristic curve analysis showed that RGDI >0.47 and LGDI >0.34 had a sensitivity and a specificity to predict reverse remodeling of 87% and 74%, 82%, and 74%, respectively. Stepwise forward multiple logistic regression analysis showed that RGDI (O.R.:13.4; 95%C.I.:4.2-120.5; P < 0.0001) was an independent determinant of a positive response to CRT. CONCLUSION A radial global dyssynchrony index predicts left ventricular reverse remodeling after CRT.
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Affiliation(s)
- Luigi Ascione
- Division of Cardiology, S. Maria di Loreto Hospital, Naples, Italy.
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Kaszala K, Huizar JF, Ellenbogen KA. Contemporary pacemakers: what the primary care physician needs to know. Mayo Clin Proc 2008; 83:1170-86. [PMID: 18828980 DOI: 10.4065/83.10.1170] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Pacemaker therapy is most commonly initiated because of symptomatic bradycardia, usually resulting from sinus node disease. Randomized multicenter trials assessing the relative benefits of different pacing modes have made possible an evidence-based approach to the treatment of bradyarrhythmias. During the past several decades, major advances in technology and in our understanding of cardiac pathophysiology have led to the development of new pacing techniques for the treatment of heart failure in the absence of bradycardia. Left ventricular or biventricular pacing may improve symptoms of heart failure and objective measurements of left ventricular systolic dysfunction by resynchronizing cardiac contraction. However, emerging clinical data suggest that long-term right ventricular apical pacing may have harmful effects. As the complexity of cardiac pacing devices continues to grow, physicians need to have a basic understanding of device indications, device function, and common problems encountered by patients with devices in the medical and home environment.
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Affiliation(s)
- Karoly Kaszala
- Medical College of Virginia, PO Box 980053, Richmond, VA 23298-0053, USA.
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135
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Ascione L, Muto C, Iengo R, Celentano E, Accadia M, Rumolo S, D'Andrea A, Carreras G, Canciello M, Tuccillo B. End-Diastolic Wall Thickness as a Predictor of Reverse Remodelling After Cardiac Resynchronization Therapy: A Two-Dimensional Echocardiographic Study. J Am Soc Echocardiogr 2008; 21:1055-61. [DOI: 10.1016/j.echo.2008.06.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2008] [Indexed: 10/21/2022]
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Kirn B, Jansen A, Bracke F, van Gelder B, Arts T, Prinzen FW. Mechanical discoordination rather than dyssynchrony predicts reverse remodeling upon cardiac resynchronization. Am J Physiol Heart Circ Physiol 2008; 295:H640-6. [DOI: 10.1152/ajpheart.00106.2008] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
By current guidelines a considerable part of the patients selected for cardiac resynchronization therapy (CRT) do not respond to the therapy. We hypothesized that mechanical discoordination [opposite strain within the left ventricular (LV) wall] predicts reversal of LV remodeling upon CRT better than mechanical dyssynchrony. MRI tagging images were acquired in CRT candidates ( n = 19) and in healthy control subjects ( n = 9). Circumferential strain (εcc) was determined in 160 regions. From εcc signals we derived 1) an index of mechanical discoordination [internal stretch fraction (ISF), defined as the ratio of stretch to shortening during ejection] and 2) indexes of mechanical dyssynchrony: the 10–90% width of time to onset of shortening, time to peak shortening, and end-systolic strain. LV end-diastolic volume (LVEDV), end-systolic volume (LVESV), and ejection fraction (LVEF) were determined before and after 3 mo of CRT. Responders were defined as those patients in whom LVESV decreased by >15%. In responders ( n = 10), CRT increased LVEF and decreased LVEDV and LVESV (11 ± 6%, 21 ± 16%, and 30 ± 16%, respectively) significantly more ( P < 0.05) than in nonresponders (1 ± 6%, 3 ± 4%, and 5 ± 10%, respectively). Among mechanical indexes, only ISF was different between responders and nonresponders (0.53 ± 0.25 vs. 0.31 ± 0.16; P < 0.05). In patients with ISF >0.4 ( n = 10), LVESV decreased by 31 ± 18% vs. 5 ± 11% in patients with ISF <0.4 ( P < 0.05). We conclude that mechanical discoordination, as estimated from ISF, is a better predictor of reverse remodeling after CRT than differences in time to onset and time to peak shortening. Therefore, discoordination rather than dyssynchrony appears to reflect the reserve contractile capacity that can be recruited by CRT.
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Tomaske M, Breithardt OA, Balmer C, Bauersfeld U. Successful cardiac resynchronization with single-site left ventricular pacing in children. Int J Cardiol 2008; 136:136-43. [PMID: 18620766 DOI: 10.1016/j.ijcard.2008.04.048] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2007] [Revised: 04/06/2008] [Accepted: 04/23/2008] [Indexed: 12/14/2022]
Abstract
BACKGROUND Dyssynchronous left ventricular (LV) contraction due to permanent right ventricular apex (RVA) pacing or delayed electrical activation as typically observed in left bundle brunch block (LBBB) has a negative impact on LV function. Objective was to evaluate the impact of epicardial single-site LV pacing in children on LV function and resynchronization. PATIENTS Single-site epicardial LV free wall pacing was established in 6 children with congenital heart disease and echocardiographic signs of LV dyssynchrony. Reasons for dyssynchrony were either long-term RVA pacing (n=5; pacing duration: 7.7+/-2.4 years) or LBBB with drug-resistant congestive heart failure (n=1). RESULTS After 1 month of single-site LV pacing, LV ejection fraction increased (41+/-6 versus 53+/-8%) and LV enddiastolic volume decreased (70+/-22 versus 63+/-18 ml/m(2)) as compared to pre-implant measurements. Interventricular mechanical delay decreased (67+/-15 versus 16+/-15 ms) and intraventricular synchrony was restored (septal-to-posterior wall motion delay: 312+/-24 versus 95+/-57 ms). Accordingly, circumferential 2D strain demonstrated a decrease of LV mechanical delay (201+/-35 versus 99+/-23 ms). CONCLUSION After 1 month of single-site LV pacing, conventional and 2D strain derived echocardiographic measurements indicated improved ventricular function and synchronization in children with previous RVA pacing or LBBB. Further studies are needed to evaluate whether single-site LV pacing may be sufficient for resynchronization therapy.
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Affiliation(s)
- Maren Tomaske
- Division of Paediatric Cardiology, University Children's Hospital, Zurich, Switzerland.
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138
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Lim SH, Lip GYH, Sanderson JE. Ventricular optimization of biventricular pacing: a systematic review. Europace 2008; 10:901-6. [PMID: 18611967 DOI: 10.1093/europace/eun177] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Biventricular pacing has been shown to improve the overall clinical outcomes in patients with systolic heart failure and ventricular conduction delay on electrocardiogram. As correction of ventricular dyssynchrony is the putative mechanism of benefit, biventricular pacing is also termed as cardiac resynchronization therapy. The development of separate programmability of right and left ventricular output has led to a growing number of reports on the potential benefit of optimization of cardiac resynchronization by sequential biventricular pacing with different techniques and endpoints. This systematic review summarizes the current data for the optimization of sequential (V-V delay) compared with (default) simultaneous biventricular pacing in heart failure.
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Affiliation(s)
- Sern H Lim
- University Department of Medicine, City Hospital, Birmingham B18 7QH, UK.
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139
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Epstein AE, DiMarco JP, Ellenbogen KA, Estes NAM, Freedman RA, Gettes LS, Gillinov AM, Gregoratos G, Hammill SC, Hayes DL, Hlatky MA, Newby LK, Page RL, Schoenfeld MH, Silka MJ, Stevenson LW, Sweeney MO, Smith SC, Jacobs AK, Adams CD, Anderson JL, Buller CE, Creager MA, Ettinger SM, Faxon DP, Halperin JL, Hiratzka LF, Hunt SA, Krumholz HM, Kushner FG, Lytle BW, Nishimura RA, Ornato JP, Page RL, Riegel B, Tarkington LG, Yancy CW. ACC/AHA/HRS 2008 Guidelines for Device-Based Therapy of Cardiac Rhythm Abnormalities: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the ACC/AHA/NASPE 2002 Guideline Update for Implantation of Cardiac Pacemakers and Antiarrhythmia Devices) developed in collaboration with the American Association for Thoracic Surgery and Society of Thoracic Surgeons. J Am Coll Cardiol 2008; 51:e1-62. [PMID: 18498951 DOI: 10.1016/j.jacc.2008.02.032] [Citation(s) in RCA: 1098] [Impact Index Per Article: 68.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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ACC/AHA/HRS 2008 Guidelines for device-based therapy of cardiac rhythm abnormalities. Heart Rhythm 2008; 5:e1-62. [PMID: 18534360 DOI: 10.1016/j.hrthm.2008.04.014] [Citation(s) in RCA: 196] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2008] [Indexed: 01/27/2023]
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141
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Epstein AE, DiMarco JP, Ellenbogen KA, Estes NAM, Freedman RA, Gettes LS, Gillinov AM, Gregoratos G, Hammill SC, Hayes DL, Hlatky MA, Newby LK, Page RL, Schoenfeld MH, Silka MJ, Stevenson LW, Sweeney MO, Smith SC, Jacobs AK, Adams CD, Anderson JL, Buller CE, Creager MA, Ettinger SM, Faxon DP, Halperin JL, Hiratzka LF, Hunt SA, Krumholz HM, Kushner FG, Lytle BW, Nishimura RA, Ornato JP, Page RL, Riegel B, Tarkington LG, Yancy CW. ACC/AHA/HRS 2008 Guidelines for Device-Based Therapy of Cardiac Rhythm Abnormalities: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the ACC/AHA/NASPE 2002 Guideline Update for Implantation of Cardiac Pacemakers and Antiarrhythmia Devices): developed in collaboration with the American Association for Thoracic Surgery and Society of Thoracic Surgeons. Circulation 2008; 117:e350-408. [PMID: 18483207 DOI: 10.1161/circualtionaha.108.189742] [Citation(s) in RCA: 935] [Impact Index Per Article: 58.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Cha YM, Oh J, Miyazaki C, Hayes DL, Rea RF, Shen WK, Asirvatham SJ, Kemp BJ, Hodge DO, Chen PS, Chareonthaitawee P. Cardiac resynchronization therapy upregulates cardiac autonomic control. J Cardiovasc Electrophysiol 2008; 19:1045-52. [PMID: 18479331 DOI: 10.1111/j.1540-8167.2008.01190.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
OBJECTIVE To determine the effect of cardiac resynchronization therapy (CRT) on sympathetic nervous function in heart failure (HF). BACKGROUND Neurohormonal dysregulation and cardiac autonomic dysfunction are associated with HF and contribute to HF progression and its poor prognosis. We hypothesized that mechanical resynchronization improves cardiac sympathetic function in HF. METHODS Sixteen consecutive patients receiving CRT for advanced cardiomyopathy and 10 controls were included in this prospective study. NYHA class, 6-minute walk distance, echocardiographic parameters, plasma norepinephrine (NE) were assessed at baseline, 3-month and 6-month follow-up. Cardiac sympathetic function was determined by (123)iodine metaiodobenzylguanidine ((123)I-MIBG) scintigraphy and 24-hour ambulatory electrocardiography. RESULTS Along with improvement in NYHA class (3.1 +/- 0.3 to 2.1 +/- 0.4, P < 0.001) and LVEF (23 +/- 6% to 33 +/- 12%, P < 0.001), delayed heart/mediastinum (H/M) (123)I-MIBG ratio increased significantly (1.8 +/- 0.7 to 2.1 +/- 0.6, P = 0.04) while the H/M (123)I-MIBG washout rate decreased significantly (54 +/- 25% to 34 +/- 24%, P = 0.01) from baseline to 6-month follow-up. The heart rate variability (HRV) measured in SD of normal-to-normal intervals also increased significantly from baseline (82 +/- 30 ms) to follow-up (111 +/- 32 ms, P = 0.04). The improvement in NYHA after CRT was significantly associated with baseline (123)I-MIBG H/M washout rate (r = 0.65, P = 0.03). The improvement in LVESV index was associated with baseline (123)I-MIBG delayed H/M ratio (r =-0.67, P = 0.02) and H/M washout rate (r = 0.65, P = 0.03). CONCLUSION After CRT, improvements in cardiac symptoms and LV function were accompanied by rebalanced cardiac autonomic control as measured by (123)I-MIBG and HRV.
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Affiliation(s)
- Yong-Mei Cha
- Division of Cardiovascular Diseases, Department of Medicine, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.
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Gelsomino S, Lorusso R, Rostagno C, Caciolli S, Bille G, De Cicco G, Romagnoli S, Porciani C, Stefano P, Gensini GF. Prognostic value of Doppler-derived mitral deceleration time on left ventricular reverse remodelling after undersized mitral annuloplasty. EUROPEAN JOURNAL OF ECHOCARDIOGRAPHY 2008; 9:631-40. [DOI: 10.1093/ejechocard/jen034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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Gelsomino S, Lorusso R, Billè G, Rostagno C, De Cicco G, Romagnoli S, Porciani C, Tetta C, Stefàno P, Gensini GF. Left ventricular diastolic function after restrictive mitral ring annuloplasty in chronic ischemic mitral regurgitation and its predictive value on outcome and recurrence of regurgitation. Int J Cardiol 2008; 132:419-28. [PMID: 18374432 DOI: 10.1016/j.ijcard.2007.12.058] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2007] [Accepted: 12/20/2007] [Indexed: 11/19/2022]
Abstract
BACKGROUND This study was aimed at exploring the predictive value of diastolic function on clinical outcome and recurrence of ischemic mitral regurgitation following combined undersized mitral annuloplasty (UMRA) and coronary artery bypass grafting (CABG). METHODS Two hundred-thirty-four patients with chronic ischemic mitral regurgitation (CIMR) who survived combined UMRA and CABG between September 2001 and September 2007, were divided into four groups on the basis of baseline deceleration time (DT) and systolic-diastolic pulmonary venous flow ratio (S/D): Group 1, normal (n=48), Group 2, impaired relaxation (n=61), Group 3, pseudonormal (n=60) and Group 4, restrictive (n=65). Echocardiograms were performed, preoperatively, at discharge and at follow-up appointments (early, 6 months [interquartile range, IQR] 3-8 months; late, 38 months [IQR17-53 months]). RESULTS Early mortality rate was highest in the restrictive group (9.2%, p<0.001). In addition 6-year actuarial survival was significantly lower in Group 4 (p=0.025). At late follow-up, among patients in Group 4, 58.4% (n=38) had an MR grade >or=2 (p<0.001). Furthermore, DT<140 ms and S/D<0.80 were independent predictors of early (p<0.001 and 0.004, respectively) and late (both p<0.001) death. Finally DT<140 ms was the only diastolic independent predictor of MR recurrence (p<0.001). CONCLUSIONS In patients with CIMR undergoing combined CABG and UMRA restrictive LV diastolic filling pattern is an important preoperative marker of high early and late death and recurrence of MR.
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Affiliation(s)
- Sandro Gelsomino
- Cardiac Surgery Dept of Heart and Vessels, Experimental Surgery Unit, Careggi Hospital, Florence, Italy.
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145
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Bilge AK, Ozben B, Ozyigit T, Acar D, Hunerel D, Adalet K, Nisanci Y. Assessment of Early Changes in the Segmental Functions of the Left and the Right Ventricles After Biventricular Pacing in Heart Failure: A Study With Tissue Doppler Imaging. Angiology 2008; 59:179-84. [DOI: 10.1177/0003319706291173] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Tissue Doppler imaging allows assessment of systolic and diastolic regional ventricular function. The aim of this study was to assess early changes in regional systolic and diastolic functions and differences in transition time to contraction between the ventricles after cardiac resynchronization therapy. Fourteen patients were included, who underwent echocardiography before and 1 month after resynchronization. The difference between transition time to contraction of left and right ventricles decreased to 24.4 ± 10.7 milliseconds from 65.3 ± 18.2 milliseconds after resynchronization therapy ( P = .001). There was a significant relation between the decrease in difference between transition time and increase in ejection fraction (r = 0.80, P = .002). Early or late diastolic myocardial motion increased in 7 segments of left and 2 segments of right ventricles. Systolic myocardial motion increased in 7 segments of left and in all segments of right ventricles. Resynchronization therapy improved systolic and diastolic functions in both ventricles. The difference between transition time to contraction of ventricles might be helpful in estimating optimal resynchronization.
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Affiliation(s)
- Ahmet Kaya Bilge
- Istanbul University, Istanbul Faculty of Medicine, Department of Cardiology, Istanbul, Turkey
| | - Beste Ozben
- Istanbul University, Istanbul Faculty of Medicine, Department of Cardiology, Istanbul, Turkey,
| | - Tolga Ozyigit
- Istanbul University, Istanbul Faculty of Medicine, Department of Cardiology, Istanbul, Turkey
| | - Deniz Acar
- Istanbul University, Istanbul Faculty of Medicine, Department of Cardiology, Istanbul, Turkey
| | - Dilek Hunerel
- Istanbul University, Istanbul Faculty of Medicine, Department of Cardiology, Istanbul, Turkey
| | - Kamil Adalet
- Istanbul University, Istanbul Faculty of Medicine, Department of Cardiology, Istanbul, Turkey
| | - Yilmaz Nisanci
- Istanbul University, Istanbul Faculty of Medicine, Department of Cardiology, Istanbul, Turkey
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146
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Left Ventricular Reverse Remodeling After Undersized Mitral Ring Annuloplasty in Patients With Ischemic Regurgitation. Ann Thorac Surg 2008; 85:1319-30. [DOI: 10.1016/j.athoracsur.2007.12.074] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2007] [Revised: 12/23/2007] [Accepted: 12/31/2007] [Indexed: 11/23/2022]
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147
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Siegrist PT, Comte N, Holzmeister J, Sütsch G, Koepfli P, Namdar M, Duru F, Brunckhorst C, Scharf C, Kaufmann PA. Effects of AV delay programming on ventricular resynchronisation: role of radionuclide ventriculography. Eur J Nucl Med Mol Imaging 2008; 35:1516-22. [PMID: 18350288 DOI: 10.1007/s00259-008-0750-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2007] [Revised: 01/31/2008] [Accepted: 02/15/2008] [Indexed: 11/24/2022]
Abstract
PURPOSE Optimal atrioventricular delay (AVD) setting for cardiac resynchronisation therapy, i.e. biventricular pacing in patients with heart failure, remains a formidable challenge. Thus, the purpose of this study was to evaluate the effects of different AVD on inter- and intra-ventricular resynchronisation using phase histograms of radionuclide ventriculography (RNV). METHODS In 17 consecutive patients (mean age 64 +/- 6 years), RNV was performed 236 +/- 350 days after pacemaker implantation for cardiac resynchronisation therapy. Images were acquired during atrial pacing at 80 bpm and during biventricular pacing with AVD ranging from 80 to 160 ms. Inter-ventricular dyssynchrony was measured by the delay between the mean phase angles of the left and right ventricles. Intra-ventricular dyssynchrony was measured by the standard deviation (SD) of left ventricular phase histograms. RESULTS Left ventricular (LV) ejection fraction (EF) was inversely correlated to LV dyssynchrony (SD of LV phase histogram, R = -0.82, p < 0.0001). However, the increase in LVEF by biventricular pacing (mean +4.4 +/- 4%) showed only modest correlation to the resulting resynchronisation effect (characterised by a -13 +/- 8 degrees decrease in LV phase histogram SD, R = -0.38, p < 0.0001). CONCLUSION RNV is helpful in optimising pacing parameters for resynchronisation therapy. Varying AVD did not have a major impact on intra- or inter-ventricular resynchronisation. Thus, the benefit of AVD-based LVEF optimisation seems to result from atrioventricular resynchronisation.
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Affiliation(s)
- Patrick T Siegrist
- Cardiovascular Center, Universitiy Hospital Zurich NUK C 32, Raemistrasse 100, CH-8091, Zurich, Switzerland
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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: 379] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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149
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Pérez de Isla L, Porro R, Paré JC, de la Morena G, Macaya C, Zamorano J. Relationship Between Intraventricular Cardiac Asynchrony and Degree of Systolic Dysfunction. J Am Soc Echocardiogr 2008; 21:214-8. [PMID: 17904815 DOI: 10.1016/j.echo.2007.08.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2007] [Indexed: 11/20/2022]
Abstract
OBJECTIVES Cardiac asynchrony is an area of study becoming more relevant in the evaluation and management of heart failure. Our aim was to determine the prevalence of cardiac asynchrony by Doppler echocardiography and to evaluate its relationship with the degree of left ventricular (LV) systolic dysfunction. METHODS A total of 316 consecutive patients with LV ejection fraction less than 40% were enrolled. We divided them into 3 groups according to the degree of LV dysfunction: 31% to 40%, 21% to 30%, and less than 20%. Intraventricular asynchrony was evaluated using two methods: (1) measurement of the septal to posterior wall-motion delay (cut-off point 130 milliseconds); and (2) measurement of the difference between time from Q wave to LV ejection end, and the time from Q wave to the end of the systolic wave of the most delayed basal segment by Doppler tissue imaging (ejection- Doppler tissue imaging time; cut-off point 50 milliseconds). RESULTS Mean age was 62.14 +/- 13.5 years (75.7% men). No differences were found among clinical electrical and echocardiographic variables among the groups. Furthermore, no relationship was found between the existence of intraventricular cardiac asynchrony and the degree of LV systolic dysfunction. These were similar in patients with ischemic dilated cardiomyopathy and nonischemic dilated cardiomyopathy. CONCLUSIONS The degree of LV systolic dysfunction and its origin are not related to the presence of cardiac asynchrony. A specific echocardiographic Doppler study must always be performed to assess the existence of cardiac asynchrony in those who are candidates to resynchronization therapy.
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Affiliation(s)
- Leopoldo Pérez de Isla
- Unidad de Imagen Cardiovascular, Instituto Cardiovascular, Hospital Clínico San Carlos, Madrid, Spain
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Gasparini M, Regoli F, Ceriotti C, Galimberti P, Bragato R, De Vita S, Pini D, Andreuzzi B, Mangiavacchi M, Klersy C. Remission of left ventricular systolic dysfunction and of heart failure symptoms after cardiac resynchronization therapy: temporal pattern and clinical predictors. Am Heart J 2008; 155:507-14. [PMID: 18294488 DOI: 10.1016/j.ahj.2007.10.028] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2007] [Accepted: 10/24/2007] [Indexed: 10/22/2022]
Abstract
BACKGROUND The aim of the study was to determine whether cardiac resynchronization therapy (CRT) may induce a heart failure (HF) remission phase (recovery to New York Heart Association functional class I-II and regression of left ventricular [LV] dysfunction: LV ejection fraction [EF] > or = 50%) and to define the incidence and predictors of such a process. METHODS Cardiac resynchronization therapy devices were successfully implanted in 520 consecutive HF patients from 1999 to 2006 (mean age 66 years, 82% male sex, New York Heart Association class > or = II, LVEF 28%, QRS 164 milliseconds, 6-minute hall walk distance 302 m) at our institution. Follow-up data were prospectively collected every 3 to 6 months. Continuous variables were stratified in tertiles. RESULTS Over a median follow-up of 28 months, 26% of patients achieved LV remission (rate: 16 per 100 person-years). At univariate analysis, female sex (P = .032), non-coronary artery disease (CAD) etiology (P < .001), mitral regurgitation < 2/4 (P = .022), higher EF tertile (P < .001), lower diameter and volume tertiles (both P < .001), previous conventional right ventricle pacing (P = .029), and post-CRT-paced QRS (P = .008) predicted remission. At multivariate analysis, non-CAD etiology, LVEF 30% to 35%, and LV end-diastolic volume < 180 mL were strongly associated with HF remission phase (all P < .001). Concomitance of these 3 factors yielded a significantly higher remission rate compared with either no or only 1 factor (respectively, 60 vs 7 and 11 per 100 person-years, P < .001). CONCLUSIONS Cardiac resynchronization therapy induces HF remission phase in 26% of patients, even after 3 years. Non-CAD etiology and moderately compromised LV function at baseline may easily predict this process.
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