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Van De Leur RR, Wouters PC, Vessies MB, Van Stipdonk AMW, Ghossein MA, Maass AH, Prinzen FW, Vernooy K, Meine M, Van Es R. Explainable deep learning outperforms guideline criteria and QRSarea for prediction of outcome after cardiac resynchronization therapy. Europace 2022. [DOI: 10.1093/europace/euac053.482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Netherlands Organisation for Health Research and Development (ZonMw)
Background
Electrocardiogram-based prediction models for cardiac resynchronization therapy (CRT) response mainly focus on the QRS complex, but other information in the electrocardiogram (ECG) is neglected.
Purpose
We sought to identify and visualize ECG features using an explainable deep learning-based algorithm (FactorECG) to predict CRT outcome and echocardiographic response, and compare this to state-of-the-art parameters, including QRSarea.
Methods
Patients who underwent CRT implantation in three academic hospitals were analyzed for clinical outcome (death, left ventricular assist device implantation, or heart transplantation), and echocardiographic response (≥ 15% left ventricular end-systolic volume reduction at 6 months). Pre-implantation ECGs were converted into their respective FactorECG. By using a deep learning algorithm trained on 1.1 million ECGs, a compressed version of the median beat ECG was obtained, where all ECG features are summarized in only 21 explainable factors of variation (interactive tool: https://decoder.ecgx.ai). The 21 FactorECG values per patient were used in a Cox and logistic regression model, for outcome and response, respectively. Models were trained on data from two hospitals (n = 936 for outcome and n = 591 for response) and externally validated in a third hospital (n = 339 for outcome and n = 230 for response). Furthermore, ESC CRT guideline indications and vectorcardiographic QRSarea were used as a comparison.
Results
The deep learning-based approach was able to predict clinical outcome (AUC = 0.74 [95% confidence interval (CI) 0.69 - 0.80]) and echocardiographic response (AUC = 0.70 [95% CI 0.63 - 0.77]). Moreover, it significantly outperformed a model based on the ESC CRT guidelines for outcome (AUC = 0.57 [95% CI 0.50-0.63]) and response (AUC = 0.57 [95% CI 0.51 - 0.64]). In comparison with QRSarea, the deep learning-based approach performed significantly better for outcome (AUC = 0.61 [95% CI 0.53-0.69], but similar for response (AUC = 0.70 [95% CI 0.64-0.77]. Based on QRSarea and predicted probabilities of the deep learning approach, for both outcome at three years and response, four groups of similar size were identified and compared to the ESC CRT guidelines (Figure 1). Important ECG factors for poor response and clinical outcome were identified as anterior T-wave inversion (F9), increased heart rate (F10), non-LBBB morphology (F26) and increased PR-interval (F8, Figure 2).
Conclusion
Without compromising interpretability, the deep learning-based algorithm objectively identified CRT recipients with good clinical outcome and echocardiographic response. This approach outperformed QRSarea for outcome, and QRS morphology and duration as used in the ESC CRT guidelines for both outcome and echocardiographic response. Hence, most predictive information for CRT response is found within the QRS complex, whereas the complete median beat ECG provides additional predictive information for clinical outcome.
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Curila K, Jurak P, Waldauf P, Halamek J, Stros P, Smisek R, Plesinger F, Znojilova L, Leinveber P, Viscor I, Herman D, Osmancik P, Prinzen FW. Left ventricular septal pacing: how deep is enough? Europace 2022. [DOI: 10.1093/europace/euac053.431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: Public Institution(s). Main funding source(s): Charles University Research Program
Background
When pacing in the left septal area, it is not clear where the pacing lead needs to be implanted to obtain the most physiological ventricular activation during pure myocardial pacing.
Objective
To use UHF-ECG to compare ventricular activation between myocardial pacing of the left septum with and without the possibility to capture the left bundle branch by high output pacing.
Methods
This was a retrospective study of patients with bradycardia and deep septal myocardial pacing close to LBB (paraLBBP) or deep septal pacing more distant from LBB (DSTP), which both produced a pseudo-right bundle branch morphology in V1. During paraLBBP, left bundle branch capture was feasible during increasing pacing output up to 5V at 0.5 ms, but during DSTP, LBB capture was not possible during high output pacing. Only patients with both paraLBBP and DSTP were analyzed. Paced QRS morphology, presence of LBBpotential, QRSduration, R wave peak time (RWPT) in V5, lead depth in the septum and UHF-ECG parameters of dyssynchrony, i.e., e-DYS as the difference between the first and last ventricular activation and local depolarization durations in precordial leads (V1-V8d) were compared between them.
Results
From 119 consecutive bradycardia patients enrolled, we identified 23 with both paraLBBP and DSTP during an implant procedure. On X-ray, a lead tip was placed shallower during DSTP than paraLBBP (12 ± 3 vs. 15 ± 3 mm, p < 0.001). A pseudo right bundle branch block morphology was present in all cases, but LBB potential was more frequently present in paraLBBP (17 of 23) than in DSTP (4 of 36; p < 0.0001). QRSd was not significantly different (146 ± 14 vs. 142 ± 14 ms, p = 0.08), but DSTP had longer V5RWPT (86 ± 11 vs. 83 ± 9 ms; p = 0.03). paraLBBP resulted in larger interventricular dyssynchrony, e-DYS (-20 ± 15 vs. -12 ± 18 ms; p = 0.046), the same V1-6d, but its local depolarization durations in V7 and V8 (V7 and V8d) were shorter compared to DSTP (-5 and -7 ms; p < 0.05).
Conclusion
Interventricular dyssynchrony and LV lateral wall depolarization during myocardial pacing of the left septum are dependent on the relation of the leads´ tip to the LBB. Pacing positions closer to the LBB are responsible for bigger interventricular dyssynchrony and more physiological LV lateral wall depolarization.
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Ghossein MA, Salden FCWM, Van Stipdonk AMW, Janssen B, Luermans JGLM, Westra S, Prinzen FW, Vernooy K. Endocardial pacing results in better electrical resynchronization and hemodynamic improvement than epicardial pacing in CRT. Europace 2022. [DOI: 10.1093/europace/euac053.489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): The original study was financially supported by Medtronic (Minneapolis, Minnesota). The investigation of the current abstract is unrelated to the original financial support.
Background
Cardiac resynchronization therapy (CRT) is conventionally applied by means of a transvenous epicardial left ventricular (LV) lead. Studies suggest that endocardial LV pacing may result in better resynchronization and LV function than epicardial LV pacing.
Purpose
To investigate whether endocardial pacing results in better electrical resynchronization and hemodynamic improvement compared to epicardial pacing.
Methods
Patients with an indication for CRT were prospectively included from two hospitals. In all patients, LV pacing was performed endocardially and epicardially in the postero-lateral region. QRS area was calculated from vectorcardiograms that were synthesized from 12-lead ECGs. Acute hemodynamic improvement was assessed as the change in maximum rate of rise of LV-pressure (%ΔLVdP/dtmax). We assessed the effects of endocardial and epicardial LV pacing on the change in QRS area (∆QRS area) and LVdP/dtmax (%ΔLVdP/dtmax).
Results
A total of 16 patients (age 66 ± 11 years, 56% male, 31% ischemic cardiomyopathy, QRS duration 166±18ms, LBBB in 88%) were included. Endocardial pacing resulted in greater ∆QRS area than epicardial pacing (-51 ± 34 µVs vs. -24 ± 37 µVs, p = 0.021, Panel A). In addition, endocardial pacing led to a larger %ΔLVdP/dtmax as compared to epicardial pacing (21 ± 12% vs. 18 ± 9%, p = 0.025, Panel B).
Conclusion
Compared to conventional epicardial LV pacing in CRT, endocardial LV pacing results in better electrical resynchronization and acute hemodynamic improvement.
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Curila K, Jurak P, Waldauf P, Halamek J, Stros P, Smisek R, Plesinger F, Znojilova L, Leinveber P, Viscor I, Herman D, Osmancik P, Prinzen FW. Bilateral bundle branch capture during deep septal myocardial and nonselective left bundle branch pacing preserves interventricular synchrony. Europace 2022. [DOI: 10.1093/europace/euac053.430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Ministry of Health of the Czech Republic
Background
Both left bundle branch pacing (LBBP) and deep septal myocardial pacing (LVSP) are less physiological than His bundle pacing. However, pacing both anode and cathode of the lead that is positioned in the interventricular septum may provide bilateral bundle branch capture, which may result in better interventricular synchrony.
Objective
To use UHF-ECG to compare ventricular activation between HBp and bilateral bundle branch capture during left bundle branch (LBBPbi) and deep septal myocardial pacing (LVSPbi).
Methods
Studies were performed in consecutive bradycardia patients. Bipolar pacing was performed with the lead in the LBBP (pseudo right bundle branch block morphology in V1 + proved LBB capture) and LVSP (pseudo right bundle branch block morphology in V1 without proved LBB capture) positions, with the pacing output leading to bilateral bundle branch capture. QRS duration was measured from the first to the last deflection of the QRS in any lead. UHF-ECG electrical dyssynchrony parameters – e-DYS (difference between the first and last ventricular activation) and local depolarization durations in precordial leads (V1-V8d) were calculated.
Results
In 94 consecutive patients, measurements were performed during HBp (n = 75) and LVSPbi (n = 37) and LBBPbi (n = 64). The average pacing threshold leading to bilateral bundle branch capture was 2.6 V at 0.5 ms. nsHBp led to the shortest QRSd compared to sLBBPbi and LVSPbi (98 vs. 103 vs. 110 ms; p < 0.01). LVSPbi showed smallest e-DYS -2 ms vs. -8 ms during LBBPbi and 11 ms during nsHBp; p < 0.05, but V5-8d were during LVSPbi longer than during nsHBp and LBBPbi (absolute difference 4-9 ms); p < 0.05. No statistical difference in V5-V8d were observed between LBBPbi and nsHBp.
Conclusion
Bilateral bundle branch capture during LVSP and nsLBBp preserves interventricular synchrony at the same level as HBp and thus leads to more physiological ventricular activation in patients with bradycardia.
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Koopsen T, Van Osta N, Van Loon T, Van Nieuwenhoven FA, Prinzen FW, Van Klarenbosch BR, Kirkels FP, Teske AJ, Vernooy K, Delhaas T, Lumens J. A Lumped Two-Compartment Model for Simulation of Ventricular Pump and Tissue Mechanics in Ischemic Heart Disease. Front Physiol 2022; 13:782592. [PMID: 35634163 PMCID: PMC9130776 DOI: 10.3389/fphys.2022.782592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 03/10/2022] [Indexed: 11/16/2022] Open
Abstract
Introduction: Computational modeling of cardiac mechanics and hemodynamics in ischemic heart disease (IHD) is important for a better understanding of the complex relations between ischemia-induced heterogeneity of myocardial tissue properties, regional tissue mechanics, and hemodynamic pump function. We validated and applied a lumped two-compartment modeling approach for IHD integrated into the CircAdapt model of the human heart and circulation. Methods: Ischemic contractile dysfunction was simulated by subdividing a left ventricular (LV) wall segment into a hypothetical contractile and noncontractile compartment, and dysfunction severity was determined by the noncontractile volume fraction (NCVF). Myocardial stiffness was determined by the zero-passive stress length (Ls0,pas) and nonlinearity (kECM) of the passive stress-sarcomere length relation of the noncontractile compartment. Simulated end-systolic pressure volume relations (ESPVRs) for 20% acute ischemia were qualitatively compared between a two- and one-compartment simulation, and parameters of the two-compartment model were tuned to previously published canine data of regional myocardial deformation during acute and prolonged ischemia and reperfusion. In six patients with myocardial infarction (MI), the NCVF was automatically estimated using the echocardiographic LV strain and volume measurements obtained acutely and 6 months after MI. Estimated segmental NCVF values at the baseline and 6-month follow-up were compared with percentage late gadolinium enhancement (LGE) at 6-month follow-up. Results: Simulation of 20% of NCVF shifted the ESPVR rightward while moderately reducing the slope, while a one-compartment simulation caused a leftward shift with severe reduction in the slope. Through tuning of the NCVF, Ls0,pas, and kECM, it was found that manipulation of the NCVF alone reproduced the deformation during acute ischemia and reperfusion, while additional manipulations of Ls0,pas and kECM were required to reproduce deformation during prolonged ischemia and reperfusion. Out of all segments with LGE>25% at the follow-up, the majority (68%) had higher estimated NCVF at the baseline than at the follow-up. Furthermore, the baseline NCVF correlated better with percentage LGE than NCVF did at the follow-up. Conclusion: We successfully used a two-compartment model for simulation of the ventricular pump and tissue mechanics in IHD. Patient-specific optimizations using regional myocardial deformation estimated the NCVF in a small cohort of MI patients in the acute and chronic phase after MI, while estimated NCVF values closely approximated the extent of the myocardial scar at the follow-up. In future studies, this approach can facilitate deformation imaging–based estimation of myocardial tissue properties in patients with cardiovascular diseases.
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Wouters P, van de Leur R, Vessies M, van Stipdonk A, Ghossein MA, Maass AH, Prinzen FW, Vernooy K, Meine M, Van Es R. PO-658-01 EXPLAINABLE DEEP LEARNING OUTPERFORMS GUIDELINE CRITERIA FOR PREDICTION OF CARDIAC RESYNCHRONIZATION THERAPY OUTCOME. Heart Rhythm 2022. [DOI: 10.1016/j.hrthm.2022.03.298] [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: 11/04/2022]
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Ghossein MA, Driessen RG, van Rosmalen F, Sels JWE, Delnoij T, Geyik Z, Mingels AM, van Stipdonk AM, Prinzen FW, Ghossein-Doha C, van Kuijk SM, van der Horst IC, Vernooy K, van Bussel BC. Serial Assessment of Myocardial Injury Markers in Mechanically Ventilated Patients With SARS-CoV-2 (from the Prospective MaastrICCht Cohort). Am J Cardiol 2022; 170:118-127. [PMID: 35221103 PMCID: PMC8867902 DOI: 10.1016/j.amjcard.2022.01.030] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 01/07/2022] [Accepted: 01/11/2022] [Indexed: 12/16/2022]
Abstract
Myocardial injury in COVID-19 is associated with in-hospital mortality. However, the development of myocardial injury over time and whether myocardial injury in patients with COVID-19 at the intensive care unit is associated with outcome is unclear. This study prospectively investigates myocardial injury with serial measurements over the full course of intensive care unit admission in mechanically ventilated patients with COVID-19. As part of the prospective Maastricht Intensive Care COVID cohort, predefined myocardial injury markers, including high-sensitivity cardiac troponin T (hs-cTnT), N-terminal pro-B-type natriuretic peptide (NT-proBNP), and electrocardiographic characteristics were serially collected in mechanically ventilated patients with COVID-19. Linear mixed-effects regression was used to compare survivors with nonsurvivors, adjusting for gender, age, APACHE-II score, daily creatinine concentration, hypertension, diabetes mellitus, and obesity. In 90 patients, 57 (63%) were survivors and 33 (37%) nonsurvivors, and a total of 628 serial electrocardiograms, 1,565 hs-cTnT, and 1,559 NT-proBNP concentrations were assessed. Log-hs-cTnT was lower in survivors compared with nonsurvivors at day 1 (β -0.93 [-1.37; -0.49], p <0.001) and did not change over time. Log-NT-proBNP did not differ at day 1 between both groups but decreased over time in the survivor group (β -0.08 [-0.11; -0.04] p <0.001) compared with nonsurvivors. Many electrocardiographic abnormalities were present in the whole population, without significant differences between both groups. In conclusion, baseline hs-cTnT and change in NT-proBNP were strongly associated with mortality. Two-thirds of patients with COVID-19 showed electrocardiographic abnormalities. Our serial assessment suggests that myocardial injury is common in mechanically ventilated patients with COVID-19 and is associated with outcome.
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Salden FCWM, van Stipdonk A, Allaart CP, Meine M, Prinzen FW, Vernooy K. PO-688-01 ATRIOVENTRICULAR RESTORATION BY BIVENTRICULAR PACING FOR PATIENTS WITH PROLONGED PR INTERVAL: USE OF ECHOCARDIOGRAPHIC MEASUREMENTS. Heart Rhythm 2022. [DOI: 10.1016/j.hrthm.2022.03.570] [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: 11/04/2022]
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Curila K, Jurak P, Waldauf P, Halamek J, Stros P, Smisek R, Plesinger F, Znojilova L, Leinveber P, Viscor I, Herman D, Osmancik P, Prinzen FW. PO-663-05 LEFT VENTRICULAR SEPTAL PACING: HOW DEEP IS ENOUGH? Heart Rhythm 2022. [DOI: 10.1016/j.hrthm.2022.03.347] [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: 11/04/2022]
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Salden FCWM, Prinzen FW, Lumens J, Vernooy K. Atrioventricular dromotropathy: an important substrate for complete resynchronization therapy-Authors' reply. Europace 2022; 24:868-869. [PMID: 35352810 PMCID: PMC9071079 DOI: 10.1093/europace/euac037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 03/02/2022] [Indexed: 11/29/2022] Open
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Prinzen FW, Auricchio A, Mullens W, Linde C, Huizar JF. OUP accepted manuscript. Eur Heart J 2022; 43:1917-1927. [PMID: 35265992 PMCID: PMC9123241 DOI: 10.1093/eurheartj/ehac088] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 12/02/2021] [Accepted: 02/22/2022] [Indexed: 11/14/2022] Open
Abstract
Electrical disturbances, such as atrial fibrillation (AF), dyssynchrony, tachycardia, and premature ventricular contractions (PVCs), are present in most patients with heart failure (HF). While these disturbances may be the consequence of HF, increasing evidence suggests that they may also cause or aggravate HF. Animal studies show that longer-lasting left bundle branch block, tachycardia, AF, and PVCs lead to functional derangements at the organ, cellular, and molecular level. Conversely, electrical treatment may reverse or mitigate HF. Clinical studies have shown the superiority of atrial and pulmonary vein ablation for rhythm control and AV nodal ablation for rate control in AF patients when compared with medical treatment. Ablation of PVCs can also improve left ventricular function. Cardiac resynchronization therapy (CRT) is an established adjunct therapy currently undergoing several interesting innovations. The current guideline recommendations reflect the safety and efficacy of these ablation therapies and CRT, but currently, these therapies are heavily underutilized. This review focuses on the electrical treatment of HF with reduced ejection fraction (HFrEF). We believe that the team of specialists treating an HF patient should incorporate an electrophysiologist in order to achieve a more widespread use of electrical therapies in the management of HFrEF and should also include individual conditions of the patient, such as body size and gender in therapy fine-tuning.
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Prinzen FW, Lumens J, Duchenn J, Vernooy K. Electro-energetics of Biventricular, Septal and Conduction System Pacing. Arrhythm Electrophysiol Rev 2021; 10:250-257. [PMID: 35106177 PMCID: PMC8785089 DOI: 10.15420/aer.2021.30] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 10/27/2021] [Indexed: 11/10/2022] Open
Abstract
Abnormal electrical activation of the ventricles creates abnormalities in cardiac mechanics. Local contraction patterns, as reflected by strain, are not only out of phase, but also show opposing length changes in early and late activated regions. Consequently, the efficiency of cardiac pump function (the amount of stroke work generated by a unit of oxygen consumed), is approximately 30% lower in dyssynchronous than in synchronous hearts. Maintaining good cardiac efficiency appears important for long-term outcomes. Biventricular, left ventricular septal, His bundle and left bundle branch pacing may minimise the amount of pacing-induced dyssynchrony and efficiency loss when compared to conventional right ventricular pacing. An extensive animal study indicates maintenance of mechanical synchrony and efficiency during left ventricular septal pacing and data from a few clinical studies support the idea that this is also the case for left bundle branch pacing and His bundle pacing. This review discusses electro-mechanics and mechano-energetics under the various paced conditions and provides suggestions for future research.
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Wouters PC, van Everdingen WM, Vernooy K, Geelhoed B, Allaart CP, Rienstra M, Maass AH, Vos MA, Prinzen FW, Meine M, Cramer MJ. Does mechanical dyssynchrony in addition to QRS area ensure sustained response to cardiac resynchronization therapy? Eur Heart J Cardiovasc Imaging 2021; 23:1628-1635. [PMID: 34871385 PMCID: PMC9671288 DOI: 10.1093/ehjci/jeab264] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 11/23/2021] [Indexed: 11/27/2022] Open
Abstract
Aims Judicious patient selection for cardiac resynchronization therapy (CRT) may further enhance treatment response. Progress has been made by using improved markers of electrical dyssynchrony and mechanical discoordination, using QRSAREA, and systolic rebound stretch of the septum (SRSsept) or systolic stretch index (SSI), respectively. To date, the relation between these measurements has not yet been investigated. Methods and results A total of 240 CRT patients were prospectively enrolled from six centres. Patients underwent standard 12-lead electrocardiography, and echocardiography, at baseline, 6-month, and 12-month follow-up. QRSAREA was derived using vectorcardiography, and SRSsept and SSI were measured using strain-analysis. Reverse remodelling was measured as the relative decrease in left ventricular end-systolic volume, indexed to body surface area (ΔLVESVi). Sustained response was defined as ≥15% decrease in LVESVi, at both 6- and 12-month follow-up. QRSAREA and SRSsept were both strong, multivariable adjusted, variables associated with reverse remodelling. SRSsept was associated with response, but only in patients with QRSAREA ≥ 120 μVs (AUC = 0.727 vs. 0.443). Combined presence of SRSsept ≥ 2.5% and QRSAREA ≥ 120 μVs significantly increased reverse remodelling compared with high QRSAREA alone (ΔLVESVi 38 ± 21% vs. 22 ± 21%). As a result, 92% of left bundle branch block (LBBB)-patients with combined electrical and mechanical dysfunction were ‘sustained’ volumetric responders, as opposed to 51% with high QRSAREA alone. Conclusion Parameters of mechanical dyssynchrony are better associated with response in the presence of a clear underlying electrical substrate. Combined presence of high SRSsept and QRSAREA, but not high QRSAREA alone, ensures a sustained response after CRT in LBBB patients.
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Hedeer F, Ostenfeld E, Hedén B, Prinzen FW, Arheden H, Carlsson M, Engblom H. To what extent are perfusion defects seen by myocardial perfusion SPECT in patients with left bundle branch block related to myocardial infarction, ECG characteristics, and myocardial wall motion? J Nucl Cardiol 2021; 28:2910-2922. [PMID: 32451797 PMCID: PMC8709823 DOI: 10.1007/s12350-020-02180-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 04/25/2020] [Indexed: 12/04/2022]
Abstract
INTRODUCTION We investigated if uptake pattern on myocardial perfusion SPECT (MPS) in patients with left bundle branch block (LBBB) is related to myocardial fibrosis, myocardial wall motion, and electrocardiography (ECG) characteristics. METHODS Twenty-three patients (9 women) with LBBB, examined with MPS and cardiac magnetic resonance (CMR), were included. Tracer uptake on MPS was classified by visual interpretation as typical LBBB pattern (Defect+, n = 13) or not (Defect-, n = 10) and quantitatively. CMR images were evaluated for wall thickness and for myocardial wall motion both by visual assessment and by regional myocardial radial strain from feature tracking, and for presence and location of myocardial fibrosis. ECGs were analyzed regarding QRS duration and the presence of strict criteria for LBBB. RESULTS Wall thickness was slightly lower in the septum compared to the lateral wall in Defect+ patients (5.6 ± 1.1 vs 6.0 ± 1.3 mm, P = 0.03) but not in Defect- patients (5.6 ± 1.0 vs 5.6 ± 0.9 mm, P = 0.84). Defect+ patients showed a larger proportion of dyskinetic segments in the septum and hyperkinetic segments in the lateral wall compared to Defect- patients (P = 0.006 and P = 0.004, respectively). Decreased myocardial radial strain was associated with decreased tracer uptake by MPS (R = 0.37, P < 0.001). Areas of fibrosis did not match areas with uptake defect on MPS. No differences in ECG variables were seen. CONCLUSION The heterogeneous regional tracer uptake in some patients with LBBB is related to underlying regional myocardial dyskinesia, wall thickening, and wall thickness rather than stress-induced ischemia, myocardial fibrosis, or specific ECG characteristics.
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Augustin CM, Gsell MA, Karabelas E, Willemen E, Prinzen FW, Lumens J, Vigmond EJ, Plank G. A computationally efficient physiologically comprehensive 3D-0D closed-loop model of the heart and circulation. COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING 2021; 386:114092. [PMID: 34630765 PMCID: PMC7611781 DOI: 10.1016/j.cma.2021.114092] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Computer models of cardiac electro-mechanics (EM) show promise as an effective means for the quantitative analysis of clinical data and, potentially, for predicting therapeutic responses. To realize such advanced applications methodological key challenges must be addressed. Enhanced computational efficiency and robustness is crucial to facilitate, within tractable time frames, model personalization, the simulation of prolonged observation periods under a broad range of conditions, and physiological completeness encompassing therapy-relevant mechanisms is needed to endow models with predictive capabilities beyond the mere replication of observations. Here, we introduce a universal feature-complete cardiac EM modeling framework that builds on a flexible method for coupling a 3D model of bi-ventricular EM to the physiologically comprehensive 0D CircAdapt model representing atrial mechanics and closed-loop circulation. A detailed mathematical description is given and efficiency, robustness, and accuracy of numerical scheme and solver implementation are evaluated. After parameterization and stabilization of the coupled 3D-0D model to a limit cycle under baseline conditions, the model's ability to replicate physiological behaviors is demonstrated, by simulating the transient response to alterations in loading conditions and contractility, as induced by experimental protocols used for assessing systolic and diastolic ventricular properties. Mechanistic completeness and computational efficiency of this novel model render advanced applications geared towards predicting acute outcomes of EM therapies feasible.
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Augustin CM, Gsell MAF, Karabelas E, Willemen E, Prinzen FW, Lumens J, Vigmond EJ, Plank G. A computationally efficient physiologically comprehensive 3D-0D closed-loop model of the heart and circulation. COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING 2021; 386:114092. [PMID: 34630765 DOI: 10.1016/jxma.2021.114092] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Computer models of cardiac electro-mechanics (EM) show promise as an effective means for the quantitative analysis of clinical data and, potentially, for predicting therapeutic responses. To realize such advanced applications methodological key challenges must be addressed. Enhanced computational efficiency and robustness is crucial to facilitate, within tractable time frames, model personalization, the simulation of prolonged observation periods under a broad range of conditions, and physiological completeness encompassing therapy-relevant mechanisms is needed to endow models with predictive capabilities beyond the mere replication of observations. Here, we introduce a universal feature-complete cardiac EM modeling framework that builds on a flexible method for coupling a 3D model of bi-ventricular EM to the physiologically comprehensive 0D CircAdapt model representing atrial mechanics and closed-loop circulation. A detailed mathematical description is given and efficiency, robustness, and accuracy of numerical scheme and solver implementation are evaluated. After parameterization and stabilization of the coupled 3D-0D model to a limit cycle under baseline conditions, the model's ability to replicate physiological behaviors is demonstrated, by simulating the transient response to alterations in loading conditions and contractility, as induced by experimental protocols used for assessing systolic and diastolic ventricular properties. Mechanistic completeness and computational efficiency of this novel model render advanced applications geared towards predicting acute outcomes of EM therapies feasible.
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Salden FCWM, Huntjens PR, Schreurs R, Willemen E, Kuiper M, Wouters P, Maessen JG, Bordachar P, Delhaas T, Luermans J, Meine M, Allaart CP, van Stipdonk AMW, Prinzen FW, Lumens J, Vernooy K. Pacing therapy for atrioventricular dromotropathy: a combined computational-experimental-clinical study. Europace 2021; 24:784-795. [PMID: 34718532 PMCID: PMC9071072 DOI: 10.1093/europace/euab248] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 09/11/2021] [Indexed: 11/12/2022] Open
Abstract
AIMS Investigate haemodynamic effects, and their mechanisms, of restoring atrioventricular (AV)-coupling using pacemaker therapy in normal and failing hearts in a combined computational-experimental-clinical study. METHODS AND RESULTS Computer simulations were performed in the CircAdapt model of the normal and failing human heart and circulation. Experiments were performed in a porcine model of AV dromotropathy. In a proof-of-principle clinical study, left ventricular (LV) pressure and volume were measured in 22 heart failure (HF) patients (LV ejection fraction <35%) with prolonged PR interval (>230 ms) and narrow or non-left bundle branch block QRS complex. Computer simulations and animal studies in normal hearts showed that restoring of AV-coupling with unchanged ventricular activation sequence significantly increased LV filling, mean arterial pressure, and cardiac output by 10-15%. In computer simulations of failing hearts and in HF patients, reducing PR interval by biventricular (BiV) pacing (patients: from 300 ± 61 to 137 ± 30 ms) resulted in significant increases in LV stroke volume and stroke work (patients: 34 ± 40% and 26 ± 31%, respectively). However, worsening of ventricular dyssynchrony by using right ventricular (RV) pacing abrogated the benefit of restoring AV-coupling. In model simulations, animals and patients, the increase of LV filling and associated improvement of LV pump function coincided with both larger mitral inflow (E- and A-wave area) and reduction of diastolic mitral regurgitation. CONCLUSION Restoration of AV-coupling by BiV pacing in normal and failing hearts with prolonged AV conduction leads to considerable haemodynamic improvement. These results indicate that BiV or physiological pacing, but not RV pacing, may improve cardiac function in patients with HF and prolonged PR interval.
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Heckman LIB, Luermans JGLM, Jastrzebski M, Stipdonk AMW, Westra S, Weijs B, Den Uijl D, Linz D, Mafi-Rad M, Prinzen FW, Vernooy K. Prospective evaluation of the learning curve and electrical characteristics of left bundle branch area pacing. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.0393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Left bundle branch area pacing (LBBAP) has recently been introduced as a physiological pacing technique with a synchronous ventricular activation.
Objective
To prospectively evaluate the feasibility and learning curve, as well as the electrical characteristics of LBBAP.
Methods
In 80 consecutive LBBAP pacemaker patients, ECG characteristics during intrinsic rhythm, RV septum pacing (RVSP) and LBBAP were evaluated. From the ECG's QRS duration and LVAT (stimulus to V6 R-wave peak time, RWPT) were measured. Also, the left bundle branch potential (LBBpot) to V6 RWPT interval was measured and compared to the LVAT. After conversion of the ECG into VCG (Kors conversion matrix), QRS area, as measurement for electrical dyssynchrony, was calculated.
Results
Permanent lead implantation was successful in 77/80 patients (96%) undergoing an attempt at LBBAP. LBBAP lead implantation time as well as fluoroscopy time were significantly shorter during last 25% of implantation compared to first 25% of implantations (17±5 min vs. 33±16 min and 12±7 min vs. 21±13 min, respectively, panel A and B). LBB capture was obtained in 54/80 patients (68%). In 36/45 patients (80%) with intact AV conduction and narrow QRS an LBBpot was present. The mean interval between the LBBpot and the onset of QRS was 22±6 ms.
In the patients with narrow QRS (n=45), QRS duration increased significantly during both RVSP (139±24 ms) and LBBAP (123±21 ms), compared to intrinsic rhythm (95±13 ms).
QRS area on the other hand, increased during both RVSP (73±20 μVs) but decreased during LBBAP (41±15 μVs), to values close to intrinsic rhythm (32±16 μVs, panel C). For all patients, QRS area was significantly lower in patients with LBB capture compared to patients without capture (43±18 μVs vs 54±21 μVs, respectively).
In patients with LBB capture (n=54), LVAT was significantly shorter compared to patients without LBB capture (75±14 vs. 88±9 ms, respectively). In the patients with LBB capture, there was a significant correlation between the LBBpot – V6 RWPT and S – V6 RWPT intervals (Pearson correlation 0.739, P<0.001).
Conclusion
LBBAP is a safe and feasible technique, with a clear learning curve that seems obtained after ± 40–60 implantations. LBB capture is obtained in two-thirds of patients. Although QRS duration remains prolonged, LBBAP largely restores ventricular electrical synchrony to values close to intrinsic (narrow QRS) rhythm.
Funding Acknowledgement
Type of funding sources: None.
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Shahmohammadi M, Luo H, Westphal P, Cornelussen RN, Prinzen FW, Delhaas T. Hemodynamics-driven mathematical model of first and second heart sound generation. PLoS Comput Biol 2021; 17:e1009361. [PMID: 34550969 PMCID: PMC8489711 DOI: 10.1371/journal.pcbi.1009361] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Revised: 10/04/2021] [Accepted: 08/18/2021] [Indexed: 11/30/2022] Open
Abstract
We propose a novel, two-degree of freedom mathematical model of mechanical vibrations of the heart that generates heart sounds in CircAdapt, a complete real-time model of the cardiovascular system. Heart sounds during rest, exercise, biventricular (BiVHF), left ventricular (LVHF) and right ventricular heart failure (RVHF) were simulated to examine model functionality in various conditions. Simulated and experimental heart sound components showed both qualitative and quantitative agreements in terms of heart sound morphology, frequency, and timing. Rate of left ventricular pressure (LV dp/dtmax) and first heart sound (S1) amplitude were proportional with exercise level. The relation of the second heart sound (S2) amplitude with exercise level was less significant. BiVHF resulted in amplitude reduction of S1. LVHF resulted in reverse splitting of S2 and an amplitude reduction of only the left-sided heart sound components, whereas RVHF resulted in a prolonged splitting of S2 and only a mild amplitude reduction of the right-sided heart sound components. In conclusion, our hemodynamics-driven mathematical model provides fast and realistic simulations of heart sounds under various conditions and may be helpful to find new indicators for diagnosis and prognosis of cardiac diseases. Among various vital signals used for diagnosis and prognosis of cardiac diseases, heart sounds are not employed precisely because physicians subjectively assess their auscultatory findings. On the other hand, recorded heart sounds are also difficult to quantitatively relate to different cardiac conditions given the complex nature of their generation. We therefore employed cardiovascular modeling and developed a novel hemodynamics-driven mathematical model for heart sound generation to unravel the relationships between heart sounds and other vital signals. Simulated and experimental heart sound components showed qualitative and quantitative agreements in terms of heart sound morphology, frequency, and timing, not only during normal conditions, but also during simulated exercise and heart failure. Our model can be used to understand generation of heart sounds in more details and may be helpful to find new diagnostic indicators and treatment methods of cardiac disorders.
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Pezzuto S, Prinzen FW, Potse M, Maffessanti F, Regoli F, Caputo ML, Conte G, Krause R, Auricchio A. Reconstruction of three-dimensional biventricular activation based on the 12-lead electrocardiogram via patient-specific modelling. Europace 2021; 23:640-647. [PMID: 33241411 PMCID: PMC8025079 DOI: 10.1093/europace/euaa330] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Accepted: 10/01/2020] [Indexed: 12/27/2022] Open
Abstract
Aims Non-invasive imaging of electrical activation requires high-density body surface potential mapping. The nine electrodes of the 12-lead electrocardiogram (ECG) are insufficient for a reliable reconstruction with standard inverse methods. Patient-specific modelling may offer an alternative route to physiologically constraint the reconstruction. The aim of the study was to assess the feasibility of reconstructing the fully 3D electrical activation map of the ventricles from the 12-lead ECG and cardiovascular magnetic resonance (CMR). Methods and results Ventricular activation was estimated by iteratively optimizing the parameters (conduction velocity and sites of earliest activation) of a patient-specific model to fit the simulated to the recorded ECG. Chest and cardiac anatomy of 11 patients (QRS duration 126–180 ms, documented scar in two) were segmented from CMR images. Scar presence was assessed by magnetic resonance (MR) contrast enhancement. Activation sequences were modelled with a physiologically based propagation model and ECGs with lead field theory. Validation was performed by comparing reconstructed activation maps with those acquired by invasive electroanatomical mapping of coronary sinus/veins (CS) and right ventricular (RV) and left ventricular (LV) endocardium. The QRS complex was correctly reproduced by the model (Pearson’s correlation r = 0.923). Reconstructions accurately located the earliest and latest activated LV regions (median barycentre distance 8.2 mm, IQR 8.8 mm). Correlation of simulated with recorded activation time was very good at LV endocardium (r = 0.83) and good at CS (r = 0.68) and RV endocardium (r = 0.58). Conclusion Non-invasive assessment of biventricular 3D activation using the 12-lead ECG and MR imaging is feasible. Potential applications include patient-specific modelling and pre-/per-procedural evaluation of ventricular activation.
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Verzaal NJ, Massé S, Downar E, Nanthakumar K, Delhaas T, Prinzen FW. Exploring the cause of conduction delays in patients with repaired Tetralogy of Fallot. Europace 2021; 23:i105-i112. [PMID: 33751080 DOI: 10.1093/europace/euaa400] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 12/04/2020] [Indexed: 11/13/2022] Open
Abstract
AIMS Cardiac dyssynchrony in patients with repaired Tetralogy of Fallot (rToF) has been attributed to right bundle branch block (RBBB), fibrosis and/or the patches that are inserted during repair surgery. We aimed to investigate the basis of abnormal activation in rToF patients by mapping the electrical activation sequence during sinus rhythm (SR) and right ventricular (RV) pacing. METHODS AND RESULTS A total of 17 patients were studied [13 with rToF, 2 with left bundle branch block (LBBB), and 2 without RBBB or LBBB (non-BBB)] during medically indicated cardiac surgery. During SR and RV pacing, measurements were performed using 112-electrode RV endocardial balloons (rToF only) and biventricular epicardial sock arrays (four of the rToF and all non-rToF patients). During SR, functional lines of block occurred in five rToF patients, while RV pacing caused functional blocks in four rToF patients. The line of block persisted during both SR and RV pacing in only 2 out of 13 rToF patients. Compared to SR, RV pacing increased dispersion of septal activation, but not dispersion of endocardial and epicardial activation of the RV free wall. During pacing, RV and left ventricular activation dispersion in rToF patients were comparable to that of the non-rToF patients. CONCLUSION The results of the present study indicate that the delayed activation in the right ventricle of rToF patients is predominantly due to block(s) in the Purkinje system and that conduction in RV tissue is fairly normal.
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Ghossein MA, van Stipdonk AM, Salden FCWM, Engels EB, Zanon F, Westra S, Maass AH, Rienstra M, Prinzen FW, Vernooy K. B-PO03-192 REDUCTION IN QRS AREA CORRELATES WITH HEMODYNAMIC RESPONSE DURING CARDIAC RESYNCHRONIZATION THERAPY - DEVICE IMPLANTATION. Heart Rhythm 2021. [DOI: 10.1016/j.hrthm.2021.06.665] [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: 11/16/2022]
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Deshmukh PM, Heckman LIB, Rehman N, Romig D, Bechtol T, Deshmukh A, Prinzen FW. B-PO01-101 COMPARISON OF RIGHT VENTRICULAR, DEEP SEPTAL, AND BIVENTRICULAR PACING. Heart Rhythm 2021. [DOI: 10.1016/j.hrthm.2021.06.245] [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: 10/20/2022]
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Salden OAE, Zweerink A, Wouters P, Allaart CP, Geelhoed B, de Lange FJ, Maass AH, Rienstra M, Vernooy K, Vos MA, Meine M, Prinzen FW, Cramer MJ. The value of septal rebound stretch analysis for the prediction of volumetric response to cardiac resynchronization therapy. Eur Heart J Cardiovasc Imaging 2021; 22:37-45. [PMID: 32699908 DOI: 10.1093/ehjci/jeaa190] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 06/02/2020] [Indexed: 01/27/2023] Open
Abstract
AIMS Patient selection for cardiac resynchronization therapy (CRT) may be enhanced by evaluation of systolic myocardial stretching. We evaluate whether systolic septal rebound stretch (SRSsept) derived from speckle tracking echocardiography is a predictor of reverse remodelling after CRT and whether it holds additive predictive value over the simpler visual dyssynchrony assessment by apical rocking (ApRock). METHODS AND RESULTS The association between SRSsept and change in left ventricular end-systolic volume (ΔLVESV) at 6 months of follow-up was assessed in 200 patients. Subsequently, the additive predictive value of SRSsept over the assessment of ApRock was evaluated in patients with and without left bundle branch block (LBBB) according to strict criteria. SRSsept was independently associated with ΔLVESV (β 0.221, P = 0.002) after correction for sex, age, ischaemic cardiomyopathy, QRS morphology and duration, and ApRock. A high SRSsept (≥optimal cut-off value 2.4) also coincided with more volumetric responders (ΔLVESV ≥ -15%) than low SRSsept in the entire cohort (70.0% and 56.4%), in patients with strict LBBB (83.3% vs. 56.7%, P = 0.024), and non-LBBB (70.7% vs. 46.3%, P = 0.004). Moreover, in non-LBBB patients, SRSsept held additional predictive information over the assessment of ApRock alone since patients that showed ApRock and high SRSsept were more often volumetric responder than those with ApRock but low SRSsept (82.8% vs. 47.4%, P = 0.001). CONCLUSION SRSsept is strongly associated with CRT-induced reduction in left ventricular end-systolic volume and holds additive prognostic information over QRS morphology and ApRock. Our data suggest that CRT patient selection may be improved by assessment of SRSsept, especially in the important subgroup without strict LBBB. CLINICAL TRIAL REGISTRATION The MARC study was registered at clinicaltrials.gov: NCT01519908.
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Ploeg MC, Munts C, Prinzen FW, Turner NA, van Bilsen M, van Nieuwenhoven FA. Piezo1 Mechanosensitive Ion Channel Mediates Stretch-Induced Nppb Expression in Adult Rat Cardiac Fibroblasts. Cells 2021; 10:cells10071745. [PMID: 34359915 PMCID: PMC8303625 DOI: 10.3390/cells10071745] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 07/05/2021] [Accepted: 07/07/2021] [Indexed: 01/30/2023] Open
Abstract
In response to stretch, cardiac tissue produces natriuretic peptides, which have been suggested to have beneficial effects in heart failure patients. In the present study, we explored the mechanism of stretch-induced brain natriuretic peptide (Nppb) expression in cardiac fibroblasts. Primary adult rat cardiac fibroblasts subjected to 4 h or 24 h of cyclic stretch (10% 1 Hz) showed a 6.6-fold or 3.2-fold (p < 0.05) increased mRNA expression of Nppb, as well as induction of genes related to myofibroblast differentiation. Moreover, BNP protein secretion was upregulated 5.3-fold in stretched cardiac fibroblasts. Recombinant BNP inhibited TGFβ1-induced Acta2 expression. Nppb expression was >20-fold higher in cardiomyocytes than in cardiac fibroblasts, indicating that cardiac fibroblasts were not the main source of Nppb in the healthy heart. Yoda1, an agonist of the Piezo1 mechanosensitive ion channel, increased Nppb expression 2.1-fold (p < 0.05) and significantly induced other extracellular matrix (ECM) remodeling genes. Silencing of Piezo1 reduced the stretch-induced Nppb and Tgfb1 expression in cardiac fibroblasts. In conclusion, our study identifies Piezo1 as mediator of stretch-induced Nppb expression, as well as other remodeling genes, in cardiac fibroblasts.
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