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Nakashima T, Usami S, Aiba T, Oishi S, Kimura Y, Kawakami S, Yamada-Inoue Y, Ogata S, Ueda N, Nakajima K, Kamakura T, Wada M, Yamagata K, Ishibashi K, Miyamoto K, Noda T, Nagase S, Kanzaki H, Izumi C, Yasuda S, Kamakura S, Takaki H, Sugimachi M, Kusano K. Novel Non-Invasive Index for Prediction of Responders in Cardiac Resynchronization Therapy Using High-Resolution Magnetocardiography. Circ J 2020; 84:2166-2174. [PMID: 33162489 DOI: 10.1253/circj.cj-20-0325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND Approximately one-third of patients with advanced heart failure (HF) do not respond to cardiac resynchronization therapy (CRT). We investigated whether the left ventricular (LV) conduction pattern on magnetocardiography (MCG) can predict CRT responders.Methods and Results:This retrospective study enrolled 56 patients with advanced HF (mean [±SD] LV ejection fraction [LVEF] 23±8%; QRS duration 145±19 ms) and MCG recorded before CRT. MCG-QRS current arrow maps were classified as multidirectional (MDC; n=28) or unidirectional (UDC; n=28) conduction based on a change of either ≥35° or <35°, respectively, in the direction of the maximal current arrow after the QRS peak. Baseline New York Heart Association functional class and LVEF were comparable between the 2 groups, but QRS duration was longer and the presence of complete left bundle branch block and LV dyssynchrony was higher in the UDC than MDC group. Six months after CRT, 30 patients were defined as responders, with significantly more in the UDC than MDC group (89% vs. 14%, respectively; P<0.001). Over a 5-year follow-up, Kaplan-Meyer analysis showed that adverse cardiac events (death or implantation of an LV assist device) were less frequently observed in the UDC than MDC group (6/28 vs. 15/28, respectively; P=0.027). Multivariate analysis revealed that UDC on MCG was the most significant predictor of CRT response (odds ratio 69.8; 95% confidence interval 13.14-669.32; P<0.001). CONCLUSIONS Preoperative non-invasive MCG may predict the CRT response and long-term outcome after CRT.
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Affiliation(s)
- Takahiro Nakashima
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
| | - Shunsuke Usami
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
| | - Takeshi Aiba
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
| | - Shogo Oishi
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
| | - Yoshitaka Kimura
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
| | - Shoji Kawakami
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
| | - Yuko Yamada-Inoue
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
| | - Soshiro Ogata
- Department of Preventive Medicine and Epidemiologic Informatics, National Cerebral and Cardiovascular Center
| | - Nobuhiko Ueda
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
| | - Kenzaburo Nakajima
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
| | - Tsukasa Kamakura
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
| | - Mitsuru Wada
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
| | - Kenichiro Yamagata
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
| | - Kohei Ishibashi
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
| | - Koji Miyamoto
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
| | - Takashi Noda
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
| | - Satoshi Nagase
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
| | - Hideaki Kanzaki
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
| | - Chisato Izumi
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
| | - Satoshi Yasuda
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
| | - Shiro Kamakura
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
| | - Hiroshi Takaki
- Department of Cardiovascular Dynamics, National Cerebral and Cardiovascular Center
| | - Masaru Sugimachi
- Department of Cardiovascular Dynamics, National Cerebral and Cardiovascular Center
| | - Kengo Kusano
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
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Elsaid O, Gulati V, Tecson K, Friedman M, Kluger J. Ventricular electrical delay as a predictor of arrhythmias in patients with cardiac resynchronization implantable cardioverter defibrillator. SCAND CARDIOVASC J 2018; 52:356-361. [PMID: 30570402 DOI: 10.1080/14017431.2018.1562202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
BACKGROUND Left ventricular (LV) remodeling and clinical response to cardiac resynchronization therapy (CRT) is inversely related to electrical dyssynchrony, measured as LV lead electrical delay (QLV). Presence of atrial or ventricular arrhythmia is correlated with worsening heart failure and LV remodeling. OBJECTIVE We sought to assess the association of QLV with arrhythmic events in CRT recipients. METHODS We identified patients implanted with a CRT device at our center. QLV interval was measured and corrected for baseline QRS (cQLV). We performed multivariable Logistic regression to assess the effect of cQLV on the occurrence of atrial/ventricular arrhythmic events. RESULTS Sixty-nine patients were included in analyses. The cQLV was significantly shorter in patients with atria tachycardia/supraventricular tachycardia (AT/SVT) events compared to patients without AT/SVT events (43.4 ± 22% vs. 60.3 ± 26.7%, p = .006). In contrast, no significant difference in cQLV was observed between patients with and without ventricular tachycardia/fibrillation (VT/VF) events (46.2 ± 25.4% vs. 56 ± 25.7%, p = .13). cQLV was significantly shorter in patients with new onset AT/SVT events compared to those without (38.3 ± 22.2% vs. 55.7 ± 25.7%, p = .028). In contrast, no significant difference in cQLV was observed between patients with and without new onset VT/VF events (44.2 ± 25.2% vs. 56.3 ± 25.5%, p = .069). Following adjusted analyses, cQLV was a significant predictor of AT/SVT, but not for VT/VF. CONCLUSION cQLV is a simple measure that can identify a vulnerable cohort of CRT patients at increased risk for atrial tachyarrhythmias, and hence can predict reverse remodeling and clinical response to CRT treatment.
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Affiliation(s)
- Ossama Elsaid
- a Henry Low Heart Center , Hartford Hospital , Hartford , CT , USA.,b Cardiology Division , Baylor University Medical Center , Dallas , TX , USA
| | - Vinay Gulati
- a Henry Low Heart Center , Hartford Hospital , Hartford , CT , USA
| | - Kristen Tecson
- b Cardiology Division , Baylor University Medical Center , Dallas , TX , USA
| | - Meir Friedman
- a Henry Low Heart Center , Hartford Hospital , Hartford , CT , USA
| | - Jeffrey Kluger
- a Henry Low Heart Center , Hartford Hospital , Hartford , CT , USA
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Gold MR, Yu Y, Singh JP, Birgersdotter-Green U, Stein KM, Wold N, Meyer TE, Ellenbogen KA. Effect of Interventricular Electrical Delay on Atrioventricular Optimization for Cardiac Resynchronization Therapy. Circ Arrhythm Electrophysiol 2018; 11:e006055. [PMID: 30354310 PMCID: PMC6110372 DOI: 10.1161/circep.117.006055] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Accepted: 06/01/2018] [Indexed: 02/06/2023]
Abstract
BACKGROUND Routine atrioventricular optimization (AVO) has not been shown to improve outcomes with cardiac resynchronization therapy (CRT). However, more recently subgroup analyses of multicenter CRT trials have identified electrocardiographic or lead positions associated with benefit from AVO. Therefore, the purpose of this analysis was to evaluate whether interventricular electrical delay modifies the impact of AVO on reverse remodeling with CRT. METHODS This substudy of the SMART-AV trial (SMARTDELAY Determined AV Optimization) included 275 subjects who were randomized to either an electrogram-based AVO (SmartDelay) or nominal atrioventricular delay (120 ms). Interventricular delay was defined as the time between the peaks of the right ventricular (RV) and left ventricular (LV) electrograms (RV-LV duration). CRT response was defined prospectively as a >15% reduction in LV end-systolic volume from implant to 6 months. RESULTS The cohort was 68% men, with a mean age of 65±11 years and LV ejection fraction of 28±8%. Longer RV-LV durations were significantly associated with CRT response ( P<0.01) for the entire cohort. Moreover, the benefit of AVO increased as RV-LV duration prolonged. At the longest quartile, there was a 4.26× greater odds of a remodeling response compared with nominal atrioventricular delays ( P=0.010). CONCLUSIONS Baseline interventricular delay predicted CRT response. At long RV-LV durations, AVO can increase the likelihood of reverse remodeling with CRT. AVO and LV lead location optimized to maximize interventricular delay may work synergistically to increase CRT response. CLINICAL TRIAL REGISTRATION URL: https://www.clinicaltrials.gov . Unique identifier: NCT00874445.
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Affiliation(s)
- Michael R. Gold
- Department of Medicine, Medical University of South Carolina, Charleston (M.R.G.)
| | - Yinghong Yu
- Department of Research, Boston Scientific, St. Paul (Y.Y.)
| | - Jagmeet P. Singh
- Department of Medicine, Massachusetts General Hospital, Boston (J.P.S.)
| | | | - Kenneth M. Stein
- Department of Clinical Sciences, Boston Scientific, St. Paul (K.M.S., N.W., T.E.M.)
| | - Nicholas Wold
- Department of Clinical Sciences, Boston Scientific, St. Paul (K.M.S., N.W., T.E.M.)
| | - Timothy E. Meyer
- Department of Clinical Sciences, Boston Scientific, St. Paul (K.M.S., N.W., T.E.M.)
| | - Kenneth A. Ellenbogen
- Department of Medicine, Virginia Commonwealth University Medical Center, Richmond (K.A.E.)
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Houston BA, Sturdivant JL, Yu Y, Gold MR. Acute biventricular hemodynamic effects of cardiac resynchronization therapy in right bundle branch block. Heart Rhythm 2018; 15:1525-1532. [PMID: 29800750 DOI: 10.1016/j.hrthm.2018.05.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Indexed: 10/16/2022]
Abstract
BACKGROUND Controversy remains regarding the use of cardiac resynchronization therapy (CRT) in patients with heart failure with right bundle branch block (RBBB) and reduced left ventricular (LV) ejection fraction. Moreover, little is known about acute hemodynamic changes with CRT in this subgroup as compared with patients with left bundle branch block (LBBB). OBJECTIVE The purpose of this study was to evaluate the acute biventricular hemodynamic response of CRT and other pacing configurations, including the effects of atrioventricular (AV) delay and atrial pacing, to understand the effects of CRT in RBBB. METHODS Forty patients (9 with RBBB and 31 with LBBB) undergoing CRT implantation underwent temporary pacing with varying configurations and AV delay. The acute hemodynamic response was assessed via invasive measurements of dP/dtmax (maximal rate of change in pressure) in the left ventricle (LV) as well as the right ventricle (RV) in patients with RBBB. RESULTS Patients with LBBB had a greater LV dP/dtmax response to CRT than did patients with RBBB. In patients with RBBB, single- or dual-site RV pacing configurations resulted in greater increases in RV dP/dtmax than did biventricular pacing. Optimal AV delays that maximized RV dP/dtmax were shorter than optimal AV delays for LV dP/dtmax. Furthermore, AV delays chosen to maximize improvement in RV dP/dtmax frequently resulted in negative effects on LV dP/dtmax. CONCLUSION These findings demonstrate a complex relationship between pacing configuration, AV delay, and hemodynamic responses. The biventricular hemodynamic response in patients with heart failure with RBBB might be improved by optimizing pacing modalities and AV delays. This may be particularly important in patients with diseases in whom RV failure predominates, such as patients with pulmonary hypertension and LV assist device.
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Affiliation(s)
- Brian A Houston
- Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina
| | - J Lacy Sturdivant
- Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina
| | - Yinghong Yu
- Boston Scientific Corporation, St. Paul, Minnesota
| | - Michael R Gold
- Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina.
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GOLD MICHAELR, LEMAN ROBERTB, WOLD NICHOLAS, STURDIVANT JLACY, YU YINGHONG. The Effect of Left Ventricular Electrical Delay on the Acute Hemodynamic Response with Cardiac Resynchronization Therapy. J Cardiovasc Electrophysiol 2014; 25:624-30. [DOI: 10.1111/jce.12372] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2013] [Revised: 01/05/2014] [Accepted: 01/07/2014] [Indexed: 11/28/2022]
Affiliation(s)
- MICHAEL R. GOLD
- Medical University of South Carolina; Charleston South Carolina USA
| | - ROBERT B. LEMAN
- Medical University of South Carolina; Charleston South Carolina USA
| | - NICHOLAS WOLD
- Boston Scientific Corporation; Saint Paul Minnesota USA
| | | | - YINGHONG YU
- Boston Scientific Corporation; Saint Paul Minnesota USA
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Spotnitz HM, Cabreriza SE, Wang DY, Quinn TA, Cheng B, Bedrosian LN, Aponte-Patel L, Smith CR. Primary endpoints of the biventricular pacing after cardiac surgery trial. Ann Thorac Surg 2013; 96:808-15. [PMID: 23866800 DOI: 10.1016/j.athoracsur.2013.04.101] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Revised: 04/18/2013] [Accepted: 04/23/2013] [Indexed: 10/26/2022]
Abstract
BACKGROUND This study sought to determine whether optimized biventricular pacing increases cardiac index in patients at risk of left ventricular dysfunction after cardiopulmonary bypass. Procedures included coronary artery bypass, aortic or mitral surgery and combinations. This trial was approved by the Columbia University Institutional Review Board and was conducted under an Investigational Device Exemption. METHODS Screening of 6,346 patients yielded 47 endpoints. With informed consent, 61 patients were randomized to pacing or control groups. Atrioventricular and interventricular delays were optimized 1 (phase I), 2 (phase II), and 12 to 24 hours (phase III) after bypass in all patients. Cardiac index was measured by thermal dilution in triplicate. A 2-sample t test assessed differences between groups and subgroups. RESULTS Cardiac index was 12% higher (2.83±0.16 [standard error of the mean] vs 2.52±0.13 liters/minute/square meter) in the paced group, less than predicted and not statistically significant (p=0.14). However, when aortic and aortic-mitral surgery groups were combined, cardiac index increased 29% in the paced group (2.90±0.19, n=14) versus controls (2.24±0.15, n=11) (p=0.0138). Using a linear mixed effects model, t-test revealed that mean arterial pressure increased with pacing versus no pacing at all optimization points (phase I 79.2±1.7 vs 74.5±1.6 mm Hg, p=0.008; phase II 75.9±1.5 vs 73.6±1.8, p=0.006; phase III 81.9±2.8 vs 79.5±2.7, p=0.002). CONCLUSIONS Cardiac index did not increase significantly overall but increased 29% after aortic valve surgery. Mean arterial pressure increased with pacing at 3 time points. Additional studies are needed to distinguish rate from resynchronization effects, emphasize atrioventricular delay optimization, and examine clinical benefits of temporary postoperative pacing.
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Affiliation(s)
- Henry M Spotnitz
- Department of Surgery, Columbia Presbyterian Medical Center, New York, New York 10032, USA.
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Gold MR, Yu Y, Singh JP, Stein KM, Birgersdotter-Green U, Meyer TE, Seth M, Ellenbogen KA. The effect of left ventricular electrical delay on AV optimization for cardiac resynchronization therapy. Heart Rhythm 2013; 10:988-93. [DOI: 10.1016/j.hrthm.2013.03.009] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2013] [Indexed: 11/26/2022]
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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, Tracy CM, Epstein AE, Darbar D, DiMarco JP, Dunbar SB, Estes NAM, Ferguson TB, Hammill SC, Karasik PE, Link MS, Marine JE, Schoenfeld MH, Shanker AJ, Silka MJ, Stevenson LW, Stevenson WG, Varosy PD. 2012 ACCF/AHA/HRS focused update incorporated into the ACCF/AHA/HRS 2008 guidelines for device-based therapy of cardiac rhythm abnormalities: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines and the Heart Rhythm Society. J Am Coll Cardiol 2012; 61:e6-75. [PMID: 23265327 DOI: 10.1016/j.jacc.2012.11.007] [Citation(s) in RCA: 560] [Impact Index Per Article: 46.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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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. 2012 ACCF/AHA/HRS focused update incorporated into the ACCF/AHA/HRS 2008 guidelines for device-based therapy of cardiac rhythm abnormalities: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines and the Heart Rhythm Society. Circulation 2012; 127:e283-352. [PMID: 23255456 DOI: 10.1161/cir.0b013e318276ce9b] [Citation(s) in RCA: 378] [Impact Index Per Article: 31.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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KYRIACOU ANDREAS, PABARI PUNAMA, WHINNETT ZACHARYI, ARRI SATPAL, WILLSON KEITH, BARUAH RESHAM, STEGEMANN BERTHOLD, MAYET JAMIL, KANAGARATNAM PRAPA, HUGHES ALUND, FRANCIS DARRELP. Fully Automatable, Reproducible, Noninvasive Simple Plethysmographic Optimization: Proof of Concept and Potential for Implantability. PACING AND CLINICAL ELECTROPHYSIOLOGY: PACE 2012; 35:948-60. [DOI: 10.1111/j.1540-8159.2012.03435.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Suzuki T, Osaka T, Kuroda Y, Hasebe H, Yokoyama E, Kamiya K, Kodama I. Potential Benefit of Bachmann’s Bundle Pacing on Left Ventricular Performance in Patients With Cardiac Resynchronized Therapy. Circ J 2012; 76:2799-806. [DOI: 10.1253/circj.cj-12-0811] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Tomoyuki Suzuki
- Division of Arrhythmia and Electrophysiology, Shizuoka Saiseikai General Hospital
- Department of Cardiovascular Research, Research Institute of Environmental Medicine, Nagoya University
| | - Toshiyuki Osaka
- Division of Arrhythmia and Electrophysiology, Shizuoka Saiseikai General Hospital
| | - Yusuke Kuroda
- Division of Arrhythmia and Electrophysiology, Shizuoka Saiseikai General Hospital
| | - Hideyuki Hasebe
- Division of Arrhythmia and Electrophysiology, Shizuoka Saiseikai General Hospital
| | - Eriko Yokoyama
- Division of Arrhythmia and Electrophysiology, Shizuoka Saiseikai General Hospital
| | - Kaichiro Kamiya
- Department of Cardiovascular Research, Research Institute of Environmental Medicine, Nagoya University
| | - Itsuo Kodama
- Department of Cardiovascular Research, Research Institute of Environmental Medicine, Nagoya University
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Donahue T, Niazi I, Leon A, Stucky M, Herrmann K. Acute and Chronic Response to CRT in Narrow QRS Patients. J Cardiovasc Transl Res 2011; 5:232-41. [DOI: 10.1007/s12265-011-9338-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2011] [Accepted: 11/24/2011] [Indexed: 10/14/2022]
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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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Echocardiographic prediction of outcome after cardiac resynchronization therapy: conventional methods and recent developments. Heart Fail Rev 2011; 16:235-50. [PMID: 21104122 PMCID: PMC3074077 DOI: 10.1007/s10741-010-9200-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Echocardiography plays an important role in patient assessment before cardiac resynchronization therapy (CRT) and can monitor many of its mechanical effects in heart failure patients. Encouraged by the highly variable individual response observed in the major CRT trials, echocardiography-based measurements of mechanical dyssynchrony have been extensively investigated with the aim of improving response prediction and CRT delivery. Despite recent setbacks, these techniques have continued to develop in order to overcome some of their initial flaws and limitations. This review discusses the concepts and rationale of the available echocardiographic techniques, highlighting newer quantification methods and discussing some of the unsolved issues that need to be addressed.
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Gold MR, Niazi I, Giudici M, Leman RB, Sturdivant JL, Kim MH, Yu Y. A prospective, randomized comparison of the acute hemodynamic effects of biventricular and left ventricular pacing with cardiac resynchronization therapy. Heart Rhythm 2011; 8:685-91. [DOI: 10.1016/j.hrthm.2010.12.039] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Accepted: 12/22/2010] [Indexed: 12/31/2022]
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GOLD MICHAELR, NIAZI IMRAN, GIUDICI MICHAEL, LEMAN ROBERTB, STURDIVANT JOHNL, KIM MICHAELH, WAGGONER ALAND, DING JIANG, ARCOT-KRISHNAMURTHY SHANTHA, DAUM DOUGLAS, YU YINGHONG. Acute Hemodynamic Effects of Atrial Pacing with Cardiac Resynchronization Therapy. J Cardiovasc Electrophysiol 2009; 20:894-900. [DOI: 10.1111/j.1540-8167.2009.01460.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Whinnett ZI, Davies JER, Nott G, Willson K, Manisty CH, Peters NS, Kanagaratnam P, Davies DW, Hughes AD, Mayet J, Francis DP. Efficiency, reproducibility and agreement of five different hemodynamic measures for optimization of cardiac resynchronization therapy. Int J Cardiol 2008; 129:216-26. [PMID: 17881070 DOI: 10.1016/j.ijcard.2007.08.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2006] [Revised: 06/28/2007] [Accepted: 08/03/2007] [Indexed: 11/27/2022]
Abstract
BACKGROUND Several hemodynamic measures have been used for optimization of the AV delay of cardiac resynchronization therapy (CRT), including pulse pressure (PP), systolic blood pressure (SBP) and cardiac output (CO). We aimed to determine whether these measures identify the same optimum and whether they have the same efficiency and reproducibility at identifying this optimum. METHODS AND RESULTS In 22 patients with cardiac resynchronization therapy, we adjusted the AV delay while atrially pacing at 110 bpm and simultaneously recording SBP, diastolic blood pressure (DBP), PP, mean arterial pressure (MAP) and CO. SBP, PP and CO all had essentially the same signal-to-noise ratios (15.4+/-5.4, 15.5+/-6.4, 15.3+/-7.4 respectively p=NS). In contrast, MAP and DBP had significantly worse signal-to-noise ratios than SBP (14.2+/-5.6, p=0.003 and 12.1+/-4.4, p<0.0001 respectively). The optimal AV delay was very similar between SBP, PP, MAP and DBP. For example, the optima identified by SBP correlated strongly with those identified by PP (r=0.94), MAP (r=0.96) and DBP (r=0.90). In contrast, the optima detected by CO was poorly related to these (e.g. r=0.36 with SBP optima). Reproducibility was best for optima detected by SBP followed by MAP and PP. CONCLUSIONS Essentially the same AV optimum is identified, regardless of whether the parameter chosen for maximization is SBP, PP, MAP or DBP. We conclude that optimizing the CRT AV delay using SBP gives the best combination of efficiency and reproducibility, with PP and MAP being reasonable alternatives.
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Affiliation(s)
- Zachary I Whinnett
- International Centre for Circulatory Health, St Mary's Hospital and Imperial College, 59-61 North Wharf Road, W2 1LA, London, United Kingdom
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Rüssel IK, van Dijk J, Kleijn SA, Germans T, de Roest G, Marcus JT, Kamp O, Götte MJW, van Rossum AC. Relation between three-dimensional echocardiography derived left ventricular volume and MRI derived circumferential strain in patients eligible for cardiac resynchronization therapy. Int J Cardiovasc Imaging 2008; 25:1-11. [DOI: 10.1007/s10554-008-9339-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2008] [Accepted: 07/01/2008] [Indexed: 10/21/2022]
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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: 1101] [Impact Index Per Article: 68.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Affiliation(s)
- Michael O. Sweeney
- From the Brigham and Women’s Hospital (M.O.S.), Harvard Medical School, Boston, Mass; and the Department of Physiology (F.W.P.), Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, the Netherlands
| | - Frits W. Prinzen
- From the Brigham and Women’s Hospital (M.O.S.), Harvard Medical School, Boston, Mass; and the Department of Physiology (F.W.P.), Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, the Netherlands
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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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22
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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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Rüssel IK, Zwanenburg JJM, Germans T, Marcus JT, Allaart CP, de Cock CC, Götte MJW, van Rossum AC. Mechanical dyssynchrony or myocardial shortening as MRI predictor of response to biventricular pacing? J Magn Reson Imaging 2008; 26:1452-60. [PMID: 17968903 DOI: 10.1002/jmri.21133] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
PURPOSE To investigate whether mechanical dyssynchrony (regional timing differences) or heterogeneity (regional strain differences) in myocardial function should be used to predict the response to cardiac resynchronization therapy (CRT). MATERIALS AND METHODS Baseline mechanical function was studied with MRI in 29 patients with chronic heart failure. Using myocardial tagging, two mechanical dyssynchrony parameters were defined: the standard deviation (SD) in onset time (T onset) and in time to first peak (T peak,first) of circumferential shortening. Electrical dyssynchrony was described by QRS width. Further, two heterogeneity parameters were defined: the coefficient of variation (CV) in end-systolic strain and the difference between peak septal and lateral strain (DiffSLpeakCS). The relative increase in maximum rate of left ventricle pressure rise (dP/dt max) quantified the acute response to CRT. RESULTS The heterogeneity parameters correlated better with acute response (CV: r = 0.58, DiffSLpeakCS: r = 0.63, P < 0.005) than the mechanical dyssynchrony parameters (SD(T onset): r = 0.36, SD(T peak,first) r = 0.47, P = 0.01, but similar to electrical dyssynchrony (r = 0.62, P < 0.001). When a heterogeneity parameter was combined with electrical dyssynchrony, the correlation increased (r > 0.70, P incr < 0.05). CONCLUSION Regional heterogeneity in myocardial shortening correlates better with response to CRT than mechanical dyssynchrony, but should be combined with electrical dyssynchrony to improve prediction of response beyond the prediction from electrical dyssynchrony only.
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Affiliation(s)
- Iris K Rüssel
- Department of Physics and Medical Technology, VU University Medical Center, Amsterdam, The Netherlands
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25
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Berberian G, Quinn TA, Cabreriza SE, Kenny JES, Garofalo CA, Weinberg AD, Spotnitz HM. Left ventricular pacing site and timing optimization during biventricular pacing using a multielectrode patch in pigs. J Thorac Cardiovasc Surg 2007; 134:574-8. [PMID: 17723801 DOI: 10.1016/j.jtcvs.2007.04.050] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2006] [Revised: 03/11/2007] [Accepted: 04/25/2007] [Indexed: 10/22/2022]
Abstract
OBJECTIVES Biventricular pacing is important therapy for congestive heart failure, reversing left ventricular dysfunction in dilated cardiomyopathy. Although left ventricular lead location and right ventricular-left ventricular delay are believed to be critical in biventricular pacing, there is no established technique for optimizing pacing site and timing. METHODS After median sternotomy in 8 anesthetized pigs, an ultrasonic flow probe was placed on the ascending aorta to measure cardiac output, and pressure catheters were inserted into both ventricles. Temporary bipolar epicardial pacing leads were attached to the right atrium and anterior right ventricle. A patch with 5 bipolar electrodes was placed behind the left ventricle. A temporary bipolar lead was also placed on the left ventricular apex. Complete heart block was established by ethanol ablation. Right ventricular pressure overload was induced by snaring the pulmonary artery until right ventricular systolic pressure doubled. Dual-chamber mode biventricular pacing was instituted at 9 right ventricular-left ventricular delays, +80 ms to -80 ms in 20 ms increments, and 6 left ventricular sites. Data from the 54 combinations of these variables were acquired in a randomized fashion. Mixed model technology was used for statistical analysis. RESULTS Qualitatively, two unique site/timing pairs were optimal. Statistically, pacing the obtuse margin at a right ventricular-left ventricular delay of +60 ms (mean cardiac output = 1.80 L/min) and the inferolateral wall at a right ventricular-left ventricular delay of -20 ms (mean cardiac output = 1.79 L/min) was superior to all other site/timing combinations (mean cardiac output = 1.71 L/min; P = .006). CONCLUSIONS Left ventricular pacing site and right ventricular-left ventricular delay can be optimized with a multielectrode patch and randomized data collection. This technique can be used further in clinical studies.
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Affiliation(s)
- George Berberian
- Department of Surgery, Columbia University, College of Physicians and Surgeons, New York, NY 10032, USA
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26
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Gold MR, Niazi I, Giudici M, Leman RB, Sturdivant JL, Kim MH, Yu Y, Ding J, Waggoner AD. A prospective comparison of AV delay programming methods for hemodynamic optimization during cardiac resynchronization therapy. J Cardiovasc Electrophysiol 2007; 18:490-6. [PMID: 17313533 DOI: 10.1111/j.1540-8167.2007.00770.x] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
INTRODUCTION There are several methods for programming the optimal AV delay (AVD) during cardiac resynchronization therapy (CRT). These include Doppler echocardiographic measurements of mitral inflow or aortic outflow velocities, an arbitrarily fixed AVD, and calculations based on intracardiac electrogram (EGM) intervals. The present study was designed to compare the acute effects of AVD programming methods during CRT. METHODS AND RESULTS We studied 28 patients at CRT implant with invasive measurements of LV dP/dt to determine the effect of AVD during atrial sensed (AS) and atrial paced (AP) modes. The optimal AVD, defined as that resulting in the maximal LV dP/dt, was then compared with that predicted by several noninvasive methods. CRT increased LV dP/dt 11% +/- 11% during AS (heart rate: 73 +/- 14 bpm) and 17% +/- 12% during AP (heart rate: 86 +/- 12 bpm) (P < 0.001 vs AS). There was an excellent correlation between the EGM method and the maximum achievable LV dP/dt (AS: R2 = 0.99, P < 0.0001, AP: R2 = 0.96, P < 0.0001) and this method performed better than other techniques. CONCLUSIONS An electrogram-based optimization method accurately predicts the optimal AVD among patients over a wide range of QRS intervals during CRT in both AS and AP modes. This simple technique may obviate the need for echocardiography for AVD programming.
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Affiliation(s)
- Michael R Gold
- Medical University of South Carolina, Charleston, South Carolina 29425, USA.
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27
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Kiuchi K, Yoshida A, Fukuzawa K, Takano T, Kanda G, Takami K, Hirata K. Identification of the Right Ventricular Pacing Site for Cardiac Resynchronization Therapy (CRT) Guided by Electroanatomical Mapping (CARTO). Circ J 2007; 71:1599-605. [PMID: 17895558 DOI: 10.1253/circj.71.1599] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND The optimal left ventricle (LV) pacing site for cardiac resynchronization therapy (CRT) has been investigated, but less is known about the optimal site in the right ventricle (RV). The present study examined whether electrical resynchronization guided by electroanatomical mapping (CARTO) results in mechanical resynchronization. METHODS AND RESULTS The study group included 13 patients indicated for CRT: 10 with nonischemic cardiomyopathy, 2 with ischemic cardiomyopathy and 1 with cardiac sarcoidosis, (mean LV ejection fraction: 32+/-10%). CARTO of the RV septum was performed to identify the site with the most delayed conduction time during LV pacing. Hemodynamic measurements were performed during conventional biventricular pacing with the RV apex and LV (C-BVP) and during biventricular pacing with the most delayed site of the RV (d-RV) and LV (D-BVP). Lead placement at 15 coronary sinus veins was examined in the 13 patients. During pacing from anterolateral veins (n=2), the d-RV was the RV apex (RVA) in 1 patient and the mid-septum in the other. During pacing from lateral veins (n=9), the d-RV comprised the RVA (n=3), the mid-septum (n=5), and the right ventricular outflow tract (RVOT) (n=1). During pacing from the posterolateral veins (n=3), the d-RV was the RVOT in all cases. In 11 of 15 sites, d-RV differed from conventional RVA. Compared with C-BVP, D-BVP produced a significant improvement in LV dp/dt. Furthermore, RV mid-septum and LV pacing markedly increased LV dp/dt and pulse pressure (PP), but RVOT and LV pacing did not. D-BVP vs C-BVP: %LV dp/dt 30+/-20 and 15+/-15%, p<0.05; RV mid-septum and LV pacing vs C-BVP: %LV dp/dt 35+/-20 and 10+/-15%, p<0.02, and vs PP 33+/-20 and 10+/-29 mmHg, p<0.02. CONCLUSIONS For pacing from the LV lateral vein, potential improvement of cardiac performance compared with that by conventional RVA placement may be realized with concomitant pacing from the d-RV (mid-septum).
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Affiliation(s)
- Kunihiko Kiuchi
- Division of Cardiovascular and Respiratory Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Kobe 650-0017, Japan
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Abstract
Heart failure constitutes a major health problem in USA and Europe. Angiotensin converting enzyme inhibitors and _ blockers were shown to reduce morbidity and mortality in patients with CHF. Yet, their effectiveness is limited. A significant number of patients with heart failure manifest myocardial conduction abnormalities. Conduction abnormalities, especially in the form of left bundle branch block (LBBB) may be associated with abnormal mechanical function. Several studies demonstrated that these patients may gain benefit from biventricular (BiV) pacing in terms of improvement in exercise tolerance, heart failure morbidity and even decreased mortality. BiV pacing was also associated with improvement in ejection fraction, reduction in the extent of mitral regurgitation and a decrease in cardiac size (reverse remodeling). However, a significant number of patients do not gain benefit from biventricular pacing despite having conduction abnormalities. The underlying reason is that the electrical activity may not closely reflect mechanical activity. Several imaging modalities and techniques have been proposed to improve the selection of patients who may benefit from biventricular pacemakers. Of those, echo-Doppler, and especially, Tissue Doppler Imaging has been demonstrated as important tools for evaluating patients for cardiac resynchronization therapy (CRT) and following their response. The advantages of echo include accessibility, portability, its cost and a high temporal resolution. Yet, it is limited by its acoustic windows and scanning angles. MRI is a useful tool for evaluating patients for CRT by providing 3-D image of myocardial function. However, it is limited for follow-up after implantation due to its cost and a potential damage to the patients or pacemakers. Dyssnchrony imaging is a rapidly evolving field. New imaging techniques such as speckle tracking are promising and close update is needed to keep track of the developments and the changes in this exciting field.
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Affiliation(s)
- Boaz D Rosen
- Division of Cardiology, Johns Hopkins University, Baltimore, MD, USA.
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29
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Sweeney MO, Ellenbogen KA, Miller EH, Sherfesee L, Sheldon T, Whellan D. The Managed Ventricular Pacing? Versus VVI 40 Pacing (MVP) Trial: Clinical Background, Rationale, Design, and Implementation. J Cardiovasc Electrophysiol 2006; 17:1295-8. [PMID: 17081208 DOI: 10.1111/j.1540-8167.2006.00656.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Implantable cardioverter defibrillators (ICDs) reduce mortality among appropriately selected patients who have had or are at risk for life-threatening ventricular arrhythmia. Right ventricular apical (RVA) pacing has been implicated in worsening heart failure and death. The optimal pacemaker mode for bradycardia support while minimizing unnecessary and potentially harmful RVA pacing has not been determined. METHODS The Managed Ventricular pacing vs. VVI 40 Pacing Trial (MVP) is a prospective, multicenter, randomized, single-blind, parallel, controlled clinical trial designed to establish whether atrial-based dual-chamber managed ventricular pacing mode (MVP) is equivalent or superior to back-up only ventricular pacing (VVI 40) among patients with standard indications for ICD therapy and no indication for bradycardia pacing. The MVP Trial is designed with 80% power to detect a 10% reduction in the primary endpoint of new or worsening heart failure or all-cause mortality in the MVP-treated group. Approximately 1,000 patients at 80 centers in the United States, Canada, Western Europe, and Israel will be randomized to MVP or VVI 40 pacing after successful implantation of a dual-chamber ICD. Heart failure therapies will be optimized in accordance with evidence-based guidelines. Prespecified secondary endpoints will include ventricular arrhythmias, atrial fibrillation, new indication for bradycardia pacing, health-related quality of life, and cost effectiveness. Enrollment began in October 2004 and concluded in April 2006. The study will be terminated upon recommendation of the Data Monitoring Committee or when the last patient enrolled and surviving has reached a minimum 2 years of follow-up. CONCLUSION The MVP Trial will meet the clinical need for carefully designed prospective studies to define the benefits of atrial-based dual-chamber minimal ventricular pacing versus single-chamber ventricular pacing in conventional ICD patients.
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Quinn TA, Berberian G, Cabreriza SE, Maskin LJ, Weinberg AD, Holmes JW, Spotnitz HM. Effects of sequential biventricular pacing during acute right ventricular pressure overload. Am J Physiol Heart Circ Physiol 2006; 291:H2380-7. [PMID: 16751291 DOI: 10.1152/ajpheart.00446.2006] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Temporary sequential biventricular pacing (BiVP) is a promising treatment for postoperative cardiac dysfunction, but the mechanism for improvement in right ventricular (RV) dysfunction is not understood. In the present study, cardiac output (CO) was optimized by sequential BiVP in six anesthetized, open-chest pigs during control and acute RV pressure overload (RVPO). Ventricular contractility was assessed by the maximum rate of increase of ventricular pressure (dP/d tmax). Mechanical interventricular synchrony was measured by the area of the normalized RV-left ventricular (LV) pressure diagram ( APP). Positive APP indicates RV pressure preceding LV pressure, whereas zero indicates complete synchrony. In the control state, CO was maximized with nearly simultaneous stimulation of the RV and LV, which increased RV ( P = 0.006) and LV dP/d tmax ( P = 0.002). During RVPO, CO was maximized with RV-first pacing, which increased RV dP/d tmax ( P = 0.007), but did not affect LV dP/d tmax, and decreased the left-to-right, end-diastolic pressure gradient ( P = 0.023). Percent increase of RV dP/d tmax was greater than LV dP/d tmax ( P = 0.014). There were no increases in end-diastolic pressure to account for increases in dP/d tmax. In control and RVPO, RV dP/dtmax was linearly related to APP ( r = 0.779, P < 0.001). The relation of CO to APP was curvilinear, with a peak in CO with positive APP in the control state ( P = 0.004) and with APP approaching zero during RVPO ( P = 0.001). These observations imply that, in our model, BiVP optimization improves CO by augmenting RV contractility. This is mediated by changes in mechanical interventricular synchrony. Afterload increases during RVPO exaggerate this effect, making CO critically dependent on simultaneous pressure generation in the RV and LV, with support of RV contractility by transmission of LV pressure across the interventricular septum.
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Affiliation(s)
- T Alexander Quinn
- Columbia Univ. College of Physicians & Surgeons, 622 W. 168th St., PH 14-103, New York, NY 10032, USA
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Jia P, Ramanathan C, Ghanem RN, Ryu K, Varma N, Rudy Y. Electrocardiographic imaging of cardiac resynchronization therapy in heart failure: observation of variable electrophysiologic responses. Heart Rhythm 2006; 3:296-310. [PMID: 16500302 PMCID: PMC2030622 DOI: 10.1016/j.hrthm.2005.11.025] [Citation(s) in RCA: 126] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2005] [Accepted: 11/22/2005] [Indexed: 11/30/2022]
Abstract
BACKGROUND Cardiac resynchronization therapy (CRT) for congestive heart failure patients with delayed left ventricular (LV) conduction is clinically beneficial in approximately 70% of patients. Unresolved issues include patient selection, lead placement, and efficacy of LV pacing alone. Being an electrical approach, detailed electrical information during CRT is critical to resolving these issues. However, electrical data from patients have been limited because of the requirement for invasive mapping. OBJECTIVES The purpose of this study was to provide observations and insights on the variable electrophysiologic responses of the heart to CRT using electrocardiographic imaging (ECGI). METHODS ECGI is a novel modality for noninvasive epicardial mapping. ECGI was conducted in eight patients undergoing CRT during native rhythm and various pacing modes. RESULTS In native rhythm (six patients), ventricular activation was heterogeneous, with latest activation in the lateral LV base in three patients and in the anterolateral, midlateral, or inferior LV in the remainder of patients. Anterior LV was susceptible to block and slow conduction. Right ventricular pacing improved electrical synchrony in two of six patients. LV pacing in three of four patients involved fusion with intrinsic excitation resulting in electrical resynchronization similar to biventricular pacing. Although generally electrical synchrony improved significantly with biventricular pacing, it was not always accompanied by clinical benefit. CONCLUSION Results suggest that (1) when accompanied by fusion, LV pacing alone can be as effective as biventricular pacing for electrical resynchronization; (2) right ventricular pacing is not effective for resynchronization; and (3) efficacy of CRT depends strongly on the patient-specific electrophysiologic substrate.
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Affiliation(s)
- Ping Jia
- Cardiac Bioelectricity Research and Training Center, Case Western Reserve University, Cleveland, Ohio
| | - Charulatha Ramanathan
- Cardiac Bioelectricity Research and Training Center, Case Western Reserve University, Cleveland, Ohio
| | - Raja N. Ghanem
- Cardiac Bioelectricity Research and Training Center, Case Western Reserve University, Cleveland, Ohio
| | - Kyungmoo Ryu
- Cardiac Bioelectricity Research and Training Center, Case Western Reserve University, Cleveland, Ohio
| | - Niraj Varma
- Cardiac Bioelectricity Research and Training Center, Case Western Reserve University, Cleveland, Ohio
- University Hospitals of Cleveland, Cleveland, Ohio
| | - Yoram Rudy
- Cardiac Bioelectricity and Arrhythmia Center, Washington University in St. Louis, St. Louis, Missouri
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Whinnett ZI, Davies JER, Willson K, Manisty CH, Chow AW, Foale RA, Davies DW, Hughes AD, Mayet J, Francis DP. Haemodynamic effects of changes in atrioventricular and interventricular delay in cardiac resynchronisation therapy show a consistent pattern: analysis of shape, magnitude and relative importance of atrioventricular and interventricular delay. Heart 2006; 92:1628-34. [PMID: 16709698 PMCID: PMC1861257 DOI: 10.1136/hrt.2005.080721] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
OBJECTIVE To assess the haemodynamic effect of simultaneously adjusting atrioventricular (AV) and interventricular (VV) delays. METHOD 35 different combinations of AV and VV delay were tested by using digital photoplethysmography (Finometer) with repeated alternations to measure relative change in systolic blood pressure (SBP(rel)) in 15 patients with cardiac resynchronisation devices for heart failure. RESULTS Changing AV delay had a larger effect than changing VV delay (range of SBP(rel) 21 v 4.2 mm Hg, p < 0.001). Each had a curvilinear effect. The curve of response to AV delay fitted extremely closely to a parabola (average R2 = 0.99, average residual variance 0.8 mm Hg2). The response to VV delay was significantly less curved (quadratic coefficient 67 v 1194 mm Hg/s2, p = 0.003) and therefore, although the residual variance was equally small (0.8 mm Hg2), the R2 value was 0.7. Reproducibility at two months was good, with the SD of the difference between two measurements of SBP(rel) being 2.5 mm Hg for AV delay (2% of mean systolic blood pressure) and 1.5 mm Hg for VV delay (1% of mean systolic blood pressure). CONCLUSIONS Changing AV and VV delays results in a curvilinear acute blood pressure response. This shape fits very closely to a parabola, which may be valuable information in developing a streamlined clinical protocol. VV delay adjustment provides an additional, albeit smaller, haemodynamic benefit to AV optimisation.
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Affiliation(s)
- Z I Whinnett
- International Centre for Circulatory Health, St Mary's Hospital and Imperial College London, London, UK.
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Raffa S, Fantoni C, Restauri L, Auricchio A. Right heart failure due to loss of right ventricular capture in a patient with atrioventricular junction ablation and biventricular pacing. PACING AND CLINICAL ELECTROPHYSIOLOGY: PACE 2006; 28:1127-30. [PMID: 16221274 DOI: 10.1111/j.1540-8159.2005.00229.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
We describe the case of a patient with atrioventricular (AV) junction ablation and chronic biventricular pacing in which intermittent dysfunction of the right ventricular (RV) lead resulted in left ventricular (LV) stimulation alone and onset of severe right heart failure. Restoration of biventricular pacing by increasing device output and then performing lead revision resolved the issue. This case provides evidence that LV pacing alone in patients with AV junction ablation may lead to severe right heart failure, most likely as a result of iatrogenic mechanical dyssynchrony within the RV. Thus, probably this pacing mode should be avoided in pacemaker-dependent patients with heart failure.
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Affiliation(s)
- Santi Raffa
- Division of Cardiology, University Hospital of Magdeburg, Germany
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Gurevitz O, Nof E, Carasso S, Luria D, Bar-Lev D, Tanami N, Eldar M, Glikson M. Programmable multiple pacing configurations help to overcome high left ventricular pacing thresholds and avoid phrenic nerve stimulation. PACING AND CLINICAL ELECTROPHYSIOLOGY: PACE 2006; 28:1255-9. [PMID: 16403156 DOI: 10.1111/j.1540-8159.2005.00265.x] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND High left ventricular pacing (LVP) thresholds and phrenic nerve stimulation (PNS) are common problems with cardiac resynchronization (CRT). Newer systems capable of multiple LVP configurations may help overcome these problems without the need for reoperation. METHODS CRT systems capable of multiple LVP configurations (Guidant models H155 and H145) were implanted in 43 patients (study group). An additional 49 patients (control group) received CRT systems (Guidant, Medtronic, Biotronik, St. Jude Medical, various models) lacking this feature. RESULTS Overall, acute high (> or =2.5 V/0.5 ms) LVP thresholds were encountered in 13 (30%) of the study group, and 25 (50%) of control group patients (P = 0.03). PNS was encountered in 5 (12%) of the study group and 12 (24%) of control group patients (P = 0.13). All cases of high LVP thresholds and PNS in the study group were managed by switching to a different LVP configuration, while high thresholds remained in control group patients, and PNS was managed by replacing the lead. The CS lead was successfully placed in a lateral branch in 95% of study group, compared to only 77% of control group patients (P = 0.004). CONCLUSIONS Multiple LVP configurations were clinically useful in a significant number of patients undergoing CRT system implantation by helping to overcome high LVP thresholds and PNS, and by providing more flexibility in placing the LV lead.
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Affiliation(s)
- Osnat Gurevitz
- Heart Institute, Sheba Medical Center, Tel-Hashomer, Israel, Sackler School of Medicine, Tel-Aviv University, Tel Aviv, Israel.
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Sweeney MO, Prinzen FW. A New Paradigm for Physiologic Ventricular Pacing. J Am Coll Cardiol 2006; 47:282-8. [PMID: 16412848 DOI: 10.1016/j.jacc.2005.09.029] [Citation(s) in RCA: 151] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2005] [Revised: 08/20/2005] [Accepted: 09/08/2005] [Indexed: 11/18/2022]
Abstract
Clinical trials in patients with pacemakers for sinus node dysfunction or atrioventricular block (AVB) and implantable cardioverter-defibrillators provide increasing evidence showing that desynchronization of ventricular electrical activation and contraction, induced by conventional right ventricular apex (RVA) pacing, is a serious threat for long-term cardiac morbidity and mortality. The risk of heart failure is increased even in hearts with initially normal pump function and in case of part-time ventricular pacing. These epidemiologic data fit with knowledge from decades of pathophysiological research, indicating that right ventricular (RV) pacing creates abnormal contraction, reduced pump function, hypertrophy, and ultrastructural abnormalities. This paper presents a new paradigm that aims to tailor ventricular pacing to the individual patient to achieve a way of pacing that is as physiologic as possible. In patients without AVB and no intraventricular conduction abnormalities, ventricular pacing should be avoided as much as possible, using atrial-based pacing. In patients with AVB, alternate single-site RV or left ventricular pacing or biventricular pacing may be superior to RVA pacing. Efforts to optimize the pacing mode or site should be greater in patients with a longer expected duration of pacing, poorer cardiac function, and larger mechanical asynchrony. Awareness of the problem of desynchronization should also lead to more regular monitoring of cardiac pump function and mechanical asynchrony in any patient with ventricular pacing.
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Affiliation(s)
- Michael O Sweeney
- Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA.
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Di Pede F, Gasparini G, De Piccoli B, Yu Y, Cuesta F, Raviele A. Hemodynamic Effects of Atrial Septal Pacing in Cardiac Resynchronization Therapy Patients. J Cardiovasc Electrophysiol 2005; 16:1273-8. [PMID: 16403055 DOI: 10.1111/j.1540-8167.2005.00246.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
INTRODUCTION Spontaneous or pacing-induced interatrial conduction delay may affect the outcome of heart failure patients treated with cardiac resynchronization therapy (CRT). The objective of this study was to evaluate the impact of the atrial pacing site (right atrial appendage, RAA; and low interatrial septum, LIS) during biventricular (BV) pacing on the left ventricular (LV) systolic function in candidates for CRT. METHODS AND RESULTS Fifteen heart failure patients with left bundle branch block and LV ejection fraction < or =35% were enrolled. Electrodes were placed at the RAA, LIS, right ventricular apex, and LV free wall. A DDD protocol was tested, which consisted of 50 beats in AAI mode from the RAA followed by 50 beats in BV DDD mode with atrial pacing at the RAA (DDD_RAA) or at the LIS (DDD_LIS) at four AV delays. The average (+/-SD)%LV+dP/dtmax increase during DDD_RAA and DDD_LIS pacing with respect to baseline was 24 +/- 16% and 21 +/- 15%, respectively (P < 0.01), and average percentage change in aortic pulse pressure during DDD_RAA and DDD_LIS with respect to baseline (%PP) was 13 +/- 8% and 13 +/- 7% (ns). CONCLUSIONS Our results show a significant hemodynamic improvement with both DDD_RAA and DDD_LIS biventricular pacing compared to AAI pacing. However DDD_LIS pacing was not superior to DDD_RAA pacing in acute hemodynamic responses.
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Affiliation(s)
- Francesco Di Pede
- Department of Cardiology, Ospedale Umberto I, Mestre-Venezia, Italy.
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DI PEDE FRANCESCO, GASPARINI GIANNI, DE PICCOLI BRUNO, YU YINGHONG, CUESTA FRANCISCA, RAVIELE ANTONIO. Hemodynamic Effects of Atrial Septal Pacing in Cardiac Resynchronization Therapy Patients. J Cardiovasc Electrophysiol 2005. [DOI: 10.1111/j.1540-8167.2005.50085.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Tse HF, Lee KL, Wan SH, Yu Y, Hoersch W, Pastore J, Zhu Q, Kenknight B, Spinelli J, Lau CP. Area of Left Ventricular Regional Conduction Delay and Preserved Myocardium Predict Responses to Cardiac Resynchronization Therapy. J Cardiovasc Electrophysiol 2005; 16:690-5. [PMID: 16050824 DOI: 10.1046/j.1540-8167.2005.40568.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
UNLABELLED Cardiac resynchronization therapy. BACKGROUND A significant proportion of patients with dilated cardiomyopathy and left bundle branch block (LBBB) do not respond to cardiac resynchronization therapy (CRT). The purpose of this study was to investigate whether the electromechanical properties of the myocardium would predict acute hemodynamic improvement during left ventricular (LV) pacing. METHODS AND RESULTS We studied 10 patients with idiopathic dilated cardiomyopathy and LBBB (ejection fraction (EF): 27%+/-7%; QRS duration: 166+/-16 msec) using three-dimensional electromechanical endocardial mapping technique to assess endocardial activation time (Endo-AT), unipolar voltage, and local linear shortening during sinus rhythm. LV stimulation was performed in VDD mode at five different sites and three atrioventricular delays within the coronary sinus. LV+dP/dtmax changes from baseline were measured during LV stimulation at each site (%DeltadP/dtmax). There was no significant relationship between maximum %DeltadP/dtmax during LV stimulation at the best coronary sinus site and LV EF, baseline LV+dP/dtmax, total LV Endo-AT, baseline QRS duration nor changes in QRS duration during LV pacing. However, the maximum %DeltadP/dtmax was significantly positively correlated with percentage area of late Endo-AT (r=0.97, P<0.001) and preserved LV myocardium (r=0.81, P=0.005), respectively. Patients with >20% of LV area with late Endo-AT and >30% of preserved LV myocardium had five times better acute hemodynamic response with LV stimulation. Multivariate analysis showed that only percentage area of late Endo-AT was independently correlated with %DeltadP/dtmax (P<0.05). CONCLUSION The presence of a larger amount of LV area with late Endo-AT and preserved LV myocardium measured by electromechanical mapping could identify patients who have better acute improvement in systolic performance during LV stimulation.
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Affiliation(s)
- Hung-Fat Tse
- Cardiology Division, Department of Medicine, the University of Hong Kong, Queen Mary Hospital, Hong Kong, China.
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Butter C, Stellbrink C, Belalcazar A, Villalta D, Schlegl M, Sinha A, Cuesta F, Reister C. Cardiac resynchronization therapy optimization by finger plethysmography. Heart Rhythm 2005; 1:568-75. [PMID: 15851221 DOI: 10.1016/j.hrthm.2004.07.002] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2004] [Accepted: 07/02/2004] [Indexed: 10/26/2022]
Abstract
OBJECTIVES We tested a simple noninvasive method for cardiac resynchronization therapy (CRT) optimization using standard finger photoplethysmography (FPPG). BACKGROUND CRT can increase left ventricular cardiac output in patients with heart failure and ventricular conduction delay. Optimal therapy delivery depends on an appropriate AV delay. Multiple invasive and noninvasive methods have been attempted to identify patients and the best AV delay for CRT, but all suffer from a combination of high patient risk, cost, complexity, and low reproducibility. METHODS FPPG and invasive aortic pressure data were simultaneously collected from 57 heart failure patients during intrinsic rhythm alternating with very brief periods of pacing at 4 to 5 AV delays. After correcting data for artifacts, the median percentage responses for each AV delay were classified as positive, negative, or neutral compared to baseline (Wilcoxon rank test). RESULTS FPPG correctly identified positive aortic pulse pressure responses with 71% sensitivity (95% CI: 60-80%) and 90% specificity (95% CI: 84-94%) and negative aortic pulse pressure responses with 57% sensitivity (95% CI: 44-69%) and 96% specificity (95% CI: 91-98%). The magnitude of FPPG changes were strongly correlated with positive aortic pulse pressure changes (R(2) = 0.73, P < .0001) but less well correlated with negative aortic pulse pressure changes (R(2) = 0.43, P < .0001). FPPG selected 78% of the patients having positive aortic pulse pressure changes to CRT and identified the AV delay giving maximum aortic pulse pressure change in all selected patients. CONCLUSIONS FPPG can provide a simple noninvasive method for identifying significant changes in aortic pulse pressure with high specificity, including identifying patients in whom aortic pulse pressure increases with CRT and the AV delay giving the maximum aortic pulse pressure.
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Hay I, Melenovsky V, Fetics BJ, Judge DP, Kramer A, Spinelli J, Reister C, Kass DA, Berger RD. Short-Term Effects of Right-Left Heart Sequential Cardiac Resynchronization in Patients With Heart Failure, Chronic Atrial Fibrillation, and Atrioventricular Nodal Block. Circulation 2004; 110:3404-10. [PMID: 15557370 DOI: 10.1161/01.cir.0000148177.82319.c7] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Single-site ventricular pacing in patients with heart failure, atrial fibrillation, and severe atrioventricular (AV) nodal block risks the generation of discoordinate contraction. Whether altering the site of stimulation can offset this detrimental effect and what role sequential right ventricular-left ventricular (RV-LV) stimulation might play in such patients remain unknown. METHODS AND RESULTS Nine subjects with heart failure (ejection fraction, 14% to 30%), atrial fibrillation, and AV block were studied by pressure-volume analysis. Ventricular stimulation was applied to the RV (apex and outflow tract), LV free wall, and biventricular (BiV) at 80 and 120 bpm. BiV improved systolic function more than either site alone (dP/dt(max), 810+/-83, 924+/-98, 983+/-102 mm Hg/s for RV, LV, BiV, respectively; P<0.05), although LV pacing was significantly better than RV pacing. However, only BiV improved diastolic function (isovolumic relaxation) over RV or LV alone. Similar results were obtained for both heart rates. RV pacing site did not alter the BiV effect, and concomitant stimulation of both RV sites did not improve function over each alone. Finally, varying RV-LV delay revealed optimal responses with simultaneous pacing. CONCLUSIONS Simultaneous BiV pacing acutely enhances both systolic and diastolic function over single-site RV or LV pacing in congestive heart failure patients with atrial fibrillation and advanced AV block. Sequential RV-LV stimulation offers minimal benefit on average and should perhaps be considered only in targeted subsets such as nonresponding patients.
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Affiliation(s)
- Ilan Hay
- Division of Cardiology, Department of Medicine, Johns Hopkins Medical Institutions, Baltimore, Md, USA
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Auricchio A. Pacing the left ventricle: does underlying rhythm matter?**Editorials published in the Journal of the American College of Cardiologyreflect the views of the authors and do not necessarily represent the views of JACCor the American College of Cardiology. J Am Coll Cardiol 2004; 43:239-40. [PMID: 14736443 DOI: 10.1016/j.jacc.2003.10.028] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Angelo Auricchio
- Division of Cardiology, University Hospital, Magdeburg, Germany.
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