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Zajac J, Eriksson J, Alehagen U, Ebbers T, Bolger AF, Carlhäll CJ. Mechanical dyssynchrony alters left ventricular flow energetics in failing hearts with LBBB: a 4D flow CMR pilot study. Int J Cardiovasc Imaging 2017; 34:587-596. [PMID: 29098524 PMCID: PMC5859696 DOI: 10.1007/s10554-017-1261-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 10/19/2017] [Indexed: 11/23/2022]
Abstract
The impact of left bundle branch block (LBBB) related mechanical dyssynchrony on left ventricular (LV) diastolic function remains unclear. 4D flow cardiovascular magnetic resonance (CMR) has provided reliable markers of LV dysfunction: reduced volume and kinetic energy (KE) of the portion of LV inflow which passes directly to outflow (Direct Flow) has been demonstrated in failing hearts compared to normal hearts. We sought to investigate the impact of mechanical dyssynchrony on diastolic function by comparing 4D flow in myopathic LVs with and without LBBB. CMR data were acquired at 3 T in 22 heart failure patients; 11 with LBBB and 11 without LBBB matched according to several demographic and clinical parameters. An established 4D flow analysis method was used to separate the LV end-diastolic (ED) volume into functional flow components based on the blood’s timing and route through the heart cavities. While the Direct Flow volume was not different between the groups, the KE possessed at ED was lower in LBBB patients (P = 0.018). Direct Flow entering the LV during early diastolic filling possessed less KE at ED in LBBB patients compared to non-LBBB patients, whereas no intergroup difference was observed during late filling. Pre-systolic KE of LV Direct Flow was reduced in patients with LBBB compared to matched patients with normal conduction. These intriguing findings propose that 4D flow specific measures can serve as markers of LV mechanical dyssynchrony in heart failure patients, and could possibly be investigated as predictors of response to cardiac resynchronization therapy.
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Affiliation(s)
- Jakub Zajac
- Division of Cardiovascular Medicine, Department of Medical and Health Sciences, Linköping University, 581 85, Linköping, Sweden. .,Center for Medical Image Science and Visualization (CMIV), Linköping University, Linköping, Sweden. .,Department of Clinical Physiology, Department of Medical and Health Sciences, Linköping University, Linköping, Sweden.
| | - Jonatan Eriksson
- Division of Cardiovascular Medicine, Department of Medical and Health Sciences, Linköping University, 581 85, Linköping, Sweden.,Center for Medical Image Science and Visualization (CMIV), Linköping University, Linköping, Sweden
| | - Urban Alehagen
- Division of Cardiovascular Medicine, Department of Medical and Health Sciences, Linköping University, 581 85, Linköping, Sweden.,Department of Cardiology, Department of Medical and Health Sciences, Linköping University, Linköping, Sweden
| | - Tino Ebbers
- Division of Cardiovascular Medicine, Department of Medical and Health Sciences, Linköping University, 581 85, Linköping, Sweden.,Center for Medical Image Science and Visualization (CMIV), Linköping University, Linköping, Sweden
| | - Ann F Bolger
- Division of Cardiovascular Medicine, Department of Medical and Health Sciences, Linköping University, 581 85, Linköping, Sweden.,Department of Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Carl-Johan Carlhäll
- Division of Cardiovascular Medicine, Department of Medical and Health Sciences, Linköping University, 581 85, Linköping, Sweden.,Center for Medical Image Science and Visualization (CMIV), Linköping University, Linköping, Sweden.,Department of Clinical Physiology, Department of Medical and Health Sciences, Linköping University, Linköping, Sweden
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Zhang H, Dai Z, Xiao P, Pan C, Zhang J, Hu Z, Chen S. The Left Ventricular Lead Electrical Delay Predicts Response to Cardiac Resynchronisation Therapy. Heart Lung Circ 2014; 23:936-42. [DOI: 10.1016/j.hlc.2014.04.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Revised: 02/15/2014] [Accepted: 04/03/2014] [Indexed: 10/25/2022]
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Carlomagno G, Iengo R, Sordelli C, Martiniello AR, Ascione R, Severino S, Caso P, Ascione L. Recoordination of opposing walls drives the response to cardiac resynchronization therapy: a longitudinal study using a strain discoordination index. J Cardiovasc Med (Hagerstown) 2014; 16:736-42. [PMID: 25022925 DOI: 10.2459/01.jcm.0000435620.70933.44] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND AND AIMS Intraventricular dyssynchrony has traditionally been studied by means of contraction delays between different myocardial segments. Recently, the discoordination of opposing wall contraction throughout the cardiac cycle has been proposed as a more faithful predictor of response. Aim of the current study was to evaluate which parameters - mechanical dyssynchrony or discoordination - normalize with left ventricular response to cardiac resynchronization therapy (CRT). METHODS Cardiac mechanics were analysed before and after 6 months of CRT in 53 patients with left bundle branch block and advanced heart failure. Discoordination was quantified by means of the transverse strain discoordination index (TSDI) at basal and mid-ventricular segments; this index takes into account the percentage of time in the cardiac cycle in which cardiac deformation (transverse strain) of the two opposing walls occurs in noncoordinated directions. Dyssynchrony indices included septal to lateral peak-to-peak transverse strain delay and the standard deviation of time to peak tissue velocity in 12 mid-basal segments (Yu index). RESULTS Around 63% of patients met the response criteria. Several baseline indices were predictive of reverse remodelling; TSDI at the mid-ventricular level demonstrated the best accuracy. Time from Q to peak velocity and strain tended to increase in all explored myocardial segments; despite a trend towards a decrease in septal-to-lateral strain delay, the latter decreased equally in responders and in nonresponding patients. Yu index decreased in responders more than in nonresponders, with borderline significance. Basal and medium TSDI remained unchanged in nonresponders and consistently normalized in patients who responded to CRT. The changes in TSDI were significantly correlated with improvements in left ventricular end-systolic volume and ejection fraction; the strongest correlation was observed for changes in TSDI measured at the mid-ventricular level. CONCLUSION Left ventricular reverse remodelling after CRT is accompanied by the recoordination of opposite-wall contraction, as testified by changes in mid-ventricular TSDI, which also reveals as a very good predictor of response. On the contrary, changes of segmental peak-to-peak delays (dyssynchrony indices) fail to capture the complex nature of left ventricular response to CRT.
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Affiliation(s)
- Guido Carlomagno
- aDepartment of Cardiology, Monaldi Hospital, AORN Ospedali dei Colli bDepartment of Translational Medical Sciences, Federico II University cUnit of Cardiology, Loreto Mare Hospital dSecond University of Naples, Monaldi Hospital, AORN Ospedali dei Colli, Naples, Italy
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Strik M, Regoli F, Auricchio A, Prinzen F. Electrical and mechanical ventricular activation during left bundle branch block and resynchronization. J Cardiovasc Transl Res 2012; 5:117-26. [PMID: 22311563 PMCID: PMC3294208 DOI: 10.1007/s12265-012-9351-1] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Accepted: 01/21/2012] [Indexed: 11/27/2022]
Abstract
Cardiac resynchronization therapy (CRT) aims to treat selected heart failure patients suffering from conduction abnormalities with left bundle branch block (LBBB) as the culprit disease. LBBB remained largely underinvestigated until it became apparent that the amount of response to CRT was heterogeneous and that the therapy and underlying pathology were thus incompletely understood. In this review, current knowledge concerning activation in LBBB and during biventricular pacing will be explored and applied to current CRT practice, highlighting novel ways to better measure and treat the electrical substrate.
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Affiliation(s)
- Marc Strik
- Department of Physiology, Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht 6200 MD, The Netherlands.
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Leenders GE, Cramer MJ, Bogaard MD, Meine M, Doevendans PA, De Boeck BW. Echocardiographic prediction of outcome after cardiac resynchronization therapy: conventional methods and recent developments. Heart Fail Rev 2011; 16:235-50. [PMID: 21104122 DOI: 10.1007/s10741-010-9200-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [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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