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Kristina H. Haugaa - One of the best experts on this subject based on the ideXlab platform.
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prediction of ventricular arrhythmias with left ventricular Mechanical Dispersion a systematic review and meta analysis
Jacc-cardiovascular Imaging, 2020Co-Authors: Hiroshi Kawakami, Kristina H. Haugaa, Thor Edvardsen, Nitesh Nerlekar, Thomas H. MarwickAbstract:Abstract Objectives The aim of this study was to assess the association between left ventricular Mechanical Dispersion (LVMD) and the incidence of ventricular arrhythmias (VAs). Background Recent, mainly single-center, studies have demonstrated that LVMD assessed using speckle tracking might be a powerful marker in risk stratification for VA. A systematic review and meta-analysis provides a means of understanding the prognostic value of this parameter, relative to other parameters, the most appropriate cutoff for designating risk. Methods A systemic review of studies reporting the predictive value of LVMD for VA was undertaken from a search of MEDLINE and Embase. VA events were defined as sudden cardiac death, cardiac arrest, documented ventricular tachyarrhythmia, and appropriate implantable cardioverter-defibrillator (ICD) therapy. Hazard ratios were extracted from univariate and multivariate models reporting on the association of LVMD and VA and described as pooled estimates with 95% confidence intervals. In a meta-analysis, the predictive value of LVMD was compared with that of left ventricular ejection fraction and global longitudinal strain. Results Among 3,198 patients in 12 published studies, 387 (12%) had VA events over follow-up ranging from 17 to 70 months. Patients with VAs had greater LVMD than those without (weighted mean difference −20.3 ms; 95% confidence interval: −27.3 to −13.2; p Conclusions LVMD assessed using speckle tracking provides important predictive value for VA in patients with a number of cardiac diseases and appears to have superior predictive value over left ventricular ejection fraction and global longitudinal strain for risk stratification.
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P5976Prediction of ventricular arrhythmias with Mechanical Dispersion assessed by strain echocardiography: a systematic review and meta-analysis
European Heart Journal, 2019Co-Authors: H Kawakami, Kristina H. Haugaa, Thor Edvardsen, Nitesh Nerlekar, Thomas H. MarwickAbstract:Abstract Background Recent studies have demonstrated that left ventricular Mechanical Dispersion (LVMD) assessed by speckle tracking might be a powerful marker in risk stratification for ventricular arrhythmias (VA). We sought to perform a systematic review and meta-analysis to i) assess the prognostic value of this parameter (previous studies were predominantly single-center), ii) define the value relative to other parameters, iii) identify the most appropriate cutoff for designating risk. Purpose To assess the association between LVMD and the incidence of VA. Methods A systemic review of studies reporting the predictive value of LVMD for VA was undertaken from a search of Medline and Embase. LVMD was defined as the standard deviation of time from Q/R on ECG to peak negative strain from each LV segment. VA events were defined as sudden cardiac death, cardiac arrest, documented ventricular tachyarrhythmia, and appropriate implantable cardioverter defibrillator therapy. Hazard ratios (HRs) were extracted from univariable and multivariable models reporting on the association of LVMD and VA and described as pooled estimates with 95% confidence intervals (CIs). In a meta-analysis, the predictive value of LVMD was compared to that of left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS). Results Among 3198 patients (weighted mean, 63 years, 30% female; 82% ischemic heart disease) in 12 published articles, 387 (12%) had VA events over a follow-up (17–70 months). Patients with VA events had a significantly greater Mechanical Dispersion compared with those without VA events (weighted mean difference, −20.3 ms; 95% CI, −27.3 to −13.2; p<0.01); 60 ms was found to be the optimal cutoff LVMD value for predicting VA events. Each 10 ms increment of LVMD was significantly and independently associated with VA events (HR, 1.19; 95% CI, 1.09 to 1.29; p<0.01). The predictive value of LVMD was superior to that of LVEF or GLS (Figure). Figure 1 Conclusion LVMD assessed by speckle tracking provides important predictive value for VA in patients with a number of cardiac diseases and appears to have superior predictive value to LVEF and GLS for risk stratification.
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Prediction of Ventricular Arrhythmias With Left Ventricular Mechanical Dispersion: A Systematic Review and Meta-Analysis.
JACC. Cardiovascular imaging, 2019Co-Authors: Hiroshi Kawakami, Kristina H. Haugaa, Thor Edvardsen, Nitesh Nerlekar, Thomas H. MarwickAbstract:The aim of this study was to assess the association between left ventricular Mechanical Dispersion (LVMD) and the incidence of ventricular arrhythmias (VAs). Recent, mainly single-center, studies have demonstrated that LVMD assessed using speckle tracking might be a powerful marker in risk stratification for VA. A systematic review and meta-analysis provides a means of understanding the prognostic value of this parameter, relative to other parameters, the most appropriate cutoff for designating risk. A systemic review of studies reporting the predictive value of LVMD for VA was undertaken from a search of MEDLINE and Embase. VA events were defined as sudden cardiac death, cardiac arrest, documented ventricular tachyarrhythmia, and appropriate implantable cardioverter-defibrillator (ICD) therapy. Hazard ratios were extracted from univariate and multivariate models reporting on the association of LVMD and VA and described as pooled estimates with 95% confidence intervals. In a meta-analysis, the predictive value of LVMD was compared with that of left ventricular ejection fraction and global longitudinal strain. Among 3,198 patients in 12 published studies, 387 (12%) had VA events over follow-up ranging from 17 to 70 months. Patients with VAs had greater LVMD than those without (weighted mean difference -20.3 ms; 95% confidence interval: -27.3 to -13.2; p < 0.01). Each 10 ms increment of LVMD was significantly and independently associated with VA events (hazard ratio: 1.19; 95% confidence interval: 1.09 to 1.29; p < 0.01). The predictive value of LVMD was superior to that of left ventricular ejection fraction or global longitudinal strain. LVMD assessed using speckle tracking provides important predictive value for VA in patients with a number of cardiac diseases and appears to have superior predictive value over left ventricular ejection fraction and global longitudinal strain for risk stratification. Copyright © 2020 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
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Mechanical Dispersion as a marker of left ventricular dysfunction and prognosis in stable coronary artery disease.
International Journal of Cardiovascular Imaging, 2019Co-Authors: Brede Kvisvik, Kristina H. Haugaa, Erika Nerdrum Aagaard, Magnus Nakrem Lyngbakken, Marit Kristine Smedsrud, Lars Mørkrid, Helge Røsjø, Bjørn Bendz, Thor EdvardsenAbstract:Assessment of global longitudinal strain (GLS) is superior to ejection fraction (EF) in the evaluation of left ventricular (LV) function in patients with stable coronary artery disease (CAD). However, the role of Mechanical Dispersion (MD) in this context remains unresolved. We aimed to evaluate the potential role of MD as a marker of LV dysfunction and long-term prognosis in stable CAD. EF, GLS and MD were assessed in 160 patients with stable CAD, 1 year after successful coronary revascularization. Serum levels of high-sensitivity cardiac troponin I (hs-cTnI) and amino-terminal pro B-type natriuretic peptide (NT-proBNP) were quantified as surrogate markers of LV dysfunction. The primary endpoint was defined as all-cause mortality, the secondary endpoint was defined as the composite of all-cause mortality and hospitalization for acute myocardial infarction or heart failure during follow-up. Whereas no associations between EF and the biochemical markers of LV function were found, both GLS and MD correlated positively with increasing levels of hs-cTnI (R = 0.315, P
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Physiological Determinants of Left Ventricular Mechanical Dispersion: A 2-Dimensional Speckle Tracking Echocardiographic Study in Healthy Volunteers.
Jacc-cardiovascular Imaging, 2017Co-Authors: Hugo Rodríguez-zanella, Kristina H. Haugaa, Francesca Boccalini, Eleonora Secco, Thor Edvardsen, Luigi P. Badano, Denisa MuraruAbstract:Two-dimensional speckle-tracking echocardiography enables the examiner to measure the timing of segmental myocardial shortening and its synchronicity by Mechanical Dispersion (MD). Prolonged MD reflects increased temporal heterogeneity of myocardial contraction and has been reported to be useful to
Victoria Delgado - One of the best experts on this subject based on the ideXlab platform.
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Left ventricular Mechanical Dispersion in ischaemic cardiomyopathy: association with myocardial scar burden and prognostic implications
European Heart Journal - Cardiovascular Imaging, 2020Co-Authors: Rachid Abou, Edgard A Prihadi, Laurien Goedemans, Rob Van Der Geest, Mohammed El Mahdiui, Martin J Schalij, Nina Ajmone Marsan, Victoria DelgadoAbstract:Abstract Aims Left ventricular (LV) Mechanical Dispersion (MD) may result from heterogeneous electrical conduction and is associated with adverse events. The present study investigated (i) the association between LV MD and the extent of LV scar as assessed with contrast-enhanced cardiac magnetic resonance (CMR) and (ii) the prognostic implications of LV MD in patients after ST-segment elevation myocardial infarction. Methods and results LV MD was calculated by echocardiography and myocardial scar was analysed on CMR data retrospectively. Infarct core and border zone were defined as ≥50% and 35–50% of maximal signal intensity, respectively. Patients were followed for the occurrence of the combined endpoint (all-cause mortality and appropriate implantable cardioverter-defibrillator therapy). In total, 96 patients (87% male, 57 ± 10 years) were included. Median LV MD was 53.5 ms [interquartile range (IQR) 43.4–62.8]. On CMR, total scar burden was 11.4% (IQR 3.8–17.1%), infarct core tissue 6.2% (IQR 2.0–12.7%), and border zone was 3.5% (IQR 1.5–5.7%). Correlations were observed between LV MD and infarct core (r = 0.517, P < 0.001), total scar burden (r = 0.497, P < 0.001), and border zone (r = 0.298, P = 0.003). In total, 14 patients (15%) reached the combined endpoint. Patients with LV MD >53.5 ms showed higher event rates as compared to their counterparts. Finally, LV MD showed the highest area under the curve for the prediction of the combined endpoint. Conclusion LV MD is correlated with LV scar burden. In addition, patients with prolonged LV MD showed higher event rates. Finally, LV MD provided the highest predictive value for the combined endpoint when compared with other parameters.
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Correlates and Long-Term Implications of Left Ventricular Mechanical Dispersion by Two-Dimensional Speckle-Tracking Echocardiography in Patients with ST-Segment Elevation Myocardial Infarction.
Journal of The American Society of Echocardiography, 2020Co-Authors: Rachid Abou, Edgard A Prihadi, Nina Ajmone Marsan, Pieter Van Der Bijl, Laurien Goedemans, Martin J Schalij, Federico Fortuni, Bart Mertens, Victoria DelgadoAbstract:Background Left ventricular (LV) Mechanical Dispersion (LVMD), measured with speckle-tracking echocardiography (STE) after ST-segment elevation myocardial infarction (STEMI), has been proposed as a measurement of regional heterogeneity of myocardial contraction and may reflect changes in the myocardial structure (e.g., fibrosis or edema). Further insight into this parameter may aid in the risk stratification of STEMI patients. Methods A total of 1,000 STEMI patients (77% male, 60 ± 12 years) treated with primary percutaneous coronary intervention were retrospectively analyzed. The LVMD was assessed with two-dimensional STE within 48 hours following the index infarction. Patients were followed for the occurrence of all-cause mortality. Results After a median follow-up of 117 months, 229 (23%) patients died. Nonsurvivors showed worse LV ejection fraction (43% ± 10% vs 48% ± 9%; P Conclusions In contemporary STEMI patients, prolonged LVMD was associated with various clinical and echocardiographic parameters. Prolonged LVMD was associated with worse long-term outcome.
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determinants and prognostic implications of left ventricular Mechanical Dispersion in aortic stenosis
European Journal of Echocardiography, 2019Co-Authors: Edgard A Prihadi, Mara E Vollema, Arnold C T Ng, Nina Ajmone Marsan, Victoria DelgadoAbstract:AIMS: The present study aimed at investigating the association between left ventricular (LV) Mechanical Dispersion measured with speckle tracking echocardiography and severity of aortic stenosis (AS) and its impact on prognosis. METHODS AND RESULTS: This retrospective study included 630 patients [age 72 (62-78) years, 61.4% men] with various grades of AS (mild AS, 19.8%; moderate AS, 37.0%; severe AS, 43.2%). LV Mechanical Dispersion (defined as standard deviation of time from Q/R on electrocardiogram to peak longitudinal strain in 17 LV segments) was assessed by speckle tracking echocardiography. Clinical, electrocardiographic, and echocardiographic determinants of increased LV Mechanical Dispersion were evaluated. During a follow-up of 107 (43-133) months, the independent association between LV Mechanical Dispersion and all-cause mortality (n = 302, 48%) was evaluated including aortic valve replacement as time-dependent co-variate. LV Mechanical Dispersion increased significantly with increasing severity of AS (mild AS, 54.5 ± 17.2 ms; moderate AS, 56.7 ± 19.3 ms; severe AS, 70.9 ± 24.3 ms; P < 0.001). Independent determinants of increased Mechanical Dispersion included older age (β = 0.28; P = 0.003), lower LV ejection fraction (β = -0.24; P = 0.020), smaller aortic valve area (β = -8.55; P = 0.001), larger LV mass index (β = 0.20; P < 0.001), and longer QRS duration (β = 1.12 per each 10 ms increase; P = 0.012). LV Mechanical Dispersion showed incremental prognostic value for all-cause mortality (hazard ratio 1.10 per each 10 ms increase, 95% confidence interval 1.04-1.15; P < 0.001). CONCLUSION: LV Mechanical Dispersion assessed by speckle tracking echocardiography increases significantly with severity of AS and is significantly associated with all-cause mortality.
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Determinants and prognostic implications of left ventricular Mechanical Dispersion in aortic stenosis.
European Journal of Echocardiography, 2019Co-Authors: Edgard A Prihadi, Arnold C T Ng, Nina Ajmone Marsan, E. Mara Vollema, Victoria DelgadoAbstract:AIMS: The present study aimed at investigating the association between left ventricular (LV) Mechanical Dispersion measured with speckle tracking echocardiography and severity of aortic stenosis (AS) and its impact on prognosis. METHODS AND RESULTS: This retrospective study included 630 patients [age 72 (62-78) years, 61.4% men] with various grades of AS (mild AS, 19.8%; moderate AS, 37.0%; severe AS, 43.2%). LV Mechanical Dispersion (defined as standard deviation of time from Q/R on electrocardiogram to peak longitudinal strain in 17 LV segments) was assessed by speckle tracking echocardiography. Clinical, electrocardiographic, and echocardiographic determinants of increased LV Mechanical Dispersion were evaluated. During a follow-up of 107 (43-133) months, the independent association between LV Mechanical Dispersion and all-cause mortality (n = 302, 48%) was evaluated including aortic valve replacement as time-dependent co-variate. LV Mechanical Dispersion increased significantly with increasing severity of AS (mild AS, 54.5 ± 17.2 ms; moderate AS, 56.7 ± 19.3 ms; severe AS, 70.9 ± 24.3 ms; P
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Reduced left ventricular Mechanical Dispersion at 6 months follow-up after cardiac resynchronization therapy is associated with superior long-term outcome.
Heart Rhythm, 2018Co-Authors: Pieter Van Der Bijl, Nina Ajmone Marsan, Melissa Leung, Mand J.h. Khidir, Bart Mertens, Dilek Yilmaz, Victoria DelgadoAbstract:Background In heart failure (HF) patients, left ventricular Mechanical Dispersion (LVMD) reflects heterogeneous Mechanical activation of the left ventricle. In HF patients, LVMD can be reduced after CRT. Whether lesser LVMD is associated with improved outcome is unknown. Objective The purpose of this study was to relate LVMD to long-term prognosis in a large cohort of HF patients after 6 months of cardiac resynchronization therapy (CRT). Methods Clinical, echocardiographic, and ventricular arrhythmia (VA) data were analyzed from an ongoing registry of HF recipients of CRT. Baseline (before CRT) and 6-month echocardiograms were evaluated. LVMD was calculated as the standard deviation of the time from onset of the QRS complex to the peak longitudinal strain in a 17-segment model. Patients were divided into 2 groups according to the median LVMD (84 ms) at 6 months post-CRT. Results Of 1185 patients (mean age 65 ± 10 years; 76% male), 343 (29%) died during a mean follow-up of 55 ± 36 months. Baseline LVMD was not associated with all-cause mortality and VA at follow-up. In contrast, patients with less LVMD (≤84 ms) at 6 months post-CRT had lower event rates (VA and mortality) compared to those with LVMD >84 ms. On multivariable analysis, greater LVMD at 6 months after CRT was independently associated with an increased risk of mortality (hazard ratio 1.002; P = .037) and VA (hazard ratio 1.003; P = .026). Conclusion Larger LVMD at 6 months after CRT is independently associated with all-cause mortality and VA. LVMD may be valuable in identifying patients who remain at high mortality risk after CRT implantation.
Otto A. Smiseth - One of the best experts on this subject based on the ideXlab platform.
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Abstract 11932: Mechanical Dispersion Predicts Ventricular Arrhythmias After Myocardial Infarction
Circulation, 2011Co-Authors: Kristina H. Haugaa, Bjørnar Grenne, Jens-uwe Voigt, Anca Florian, Benthe Sjøli, Harald Brunvand, Walter Desmet, Jesper Hastrup Svendsen, Otto A. SmisethAbstract:Introduction Prediction of ventricular arrhythmias after myocardial infarction (MI) is still insufficient. LV ejection fraction (EF) 35%. Mechanical Dispersion by strain echocardiography reflects inhomogeneous timing in myocardial contraction and has been shown to predict ventricular arrhythmias. We hypothesized that Mechanical Dispersion may improve arrhythmic risk stratification in post MI patients. Methods In this prospective multi center study we included 177 post MI patients (114 ST elevation and 63 non-ST elevation). Echocardiography was performed minimum 40 days post MI. Time from ECG R to peak negative strain was assessed in 16 longitudinal LV segments. Mechanical Dispersion was assessed as the standard deviation from these 16 time intervals, reflecting contraction heterogeneity. Results Ventricular arrhythmias defined as sustained VT, VF or sudden death duri...
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right ventricular Mechanical Dispersion is related to malignant arrhythmias a study of patients with arrhythmogenic right ventricular cardiomyopathy and subclinical right ventricular dysfunction
European Heart Journal, 2011Co-Authors: Kristina H. Haugaa, Otto A. Smiseth, Sebastian I Sarvari, Olegunnar Anfinsen, Trond P Leren, Erik Kongsgaard, Jan P AmlieAbstract:Aims We evaluated if right ventricular (RV) Mechanical Dispersion by strain was related to ventricular arrhythmias (VT/VF) in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) and if Mechanical Dispersion was increased in so far asymptomatic mutation carriers. Methods and results We included 69 patients, 42 had symptomatic ARVC and 27 were mutation positive asymptomatic family members. Forty healthy individuals served as controls. Myocardial strain was assessed in 6 RV and 16 left ventricular (LV) segments. Contraction duration (CD) in 6 RV and 16 LV segments were measured as the time from onset R on electrocardiogram to maximum myocardial shortening in each segment. The standard deviation of CD was defined as Mechanical Dispersion. Mechanical Dispersion was more pronounced in ARVC patients with arrhythmias compared with asymptomatic mutation carriers and healthy individuals in RV [52(41,63) vs. 35(23,47) vs. 13(9,19)ms, P < 0.001]. Mechanical Dispersion was more pronounced in asymptomatic mutation carriers compared with healthy individuals ( P < 0.001). Right ventricular Mechanical Dispersion predicted VT/VF in a multivariate logistic regression analysis [odds ratio (OR), 1.66 (95% confidence interval (CI) 1.06–2.58), P < 0.03]. Right ventricular and LV function by strain were reduced in symptomatic ARVC patients and correlated significantly ( R = 0.81, P < 0.001). Right ventricular and LV strain were reduced in asymptomatic mutation carriers compared with healthy individuals ( P < 0.001). Conclusion Right ventricular Mechanical Dispersion was pronounced in patients with ARVC with VT/VF. Right ventricular Mechanical Dispersion was present in asymptomatic mutation carriers and may be helpful in risk stratification. Right ventricular and LV function correlated in ARVC patients implying that ARVC is a biventricular disease.
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Mechanical Dispersion assessed by myocardial strain in patients after myocardial infarction for risk prediction of ventricular arrhythmia
Jacc-cardiovascular Imaging, 2010Co-Authors: Kristina H. Haugaa, Jens-uwe Voigt, Erik Kongsgaard, Rik Willems, Marit Kristine Smedsrud, Torkel Steen, Jan P Loennechen, Terje Skjaerpe, Gunnar Smith, Otto A. SmisethAbstract:Objectives The aim of this study was to investigate whether myocardial strain echocardiography can predict ventricular arrhythmias in patients after myocardial infarction (MI). Background Left ventricular (LV) ejection fraction (EF) is insufficient for selecting patients for implantable cardioverter-defibrillator (ICD) therapy after MI. Electrical Dispersion in infarcted myocardium facilitates malignant arrhythmia. Myocardial strain by echocardiography can quantify detailed regional and global myocardial function and timing. We hypothesized that electrical abnormalities in patients after MI will lead to LV Mechanical Dispersion, which can be measured as regional heterogeneity of contraction by myocardial strain. Methods We prospectively included 85 post-MI patients, 44 meeting primary and 41 meeting secondary ICD prevention criteria. After 2.3 years (range 0.6 to 5.5 years) of follow-up, 47 patients had no and 38 patients had 1 or more recorded arrhythmias requiring appropriate ICD therapy. Longitudinal strain was measured by speckle tracking echocardiography. The SD of time to maximum myocardial shortening in a 16-segment LV model was calculated as a parameter of Mechanical Dispersion. Global strain was calculated as average strain in a 16-segment LV model. Results The EF did not differ between ICD patients with and without arrhythmias occurring during follow-up (34 ± 11% vs. 35 ± 9%, p = 0.70). Mechanical Dispersion was greater in ICD patients with recorded ventricular arrhythmias compared with those without (85 ± 29 ms vs. 56 ± 13 ms, p 35%, global strain showed better LV function in those without recorded arrhythmias (−14.0% ± 4.0% vs. −12.0 ± 3.0%, p = 0.05), whereas the EF did not differ (44 ± 8% vs. 41 ± 5%, p = 0.23). Conclusions Mechanical Dispersion was more pronounced in post-MI patients with recurrent arrhythmias. Global strain was a marker of arrhythmias in post-MI patients with relatively preserved ventricular function. These novel parameters assessed by myocardial strain may add important information about susceptibility for ventricular arrhythmias after MI.
François Dupret - One of the best experts on this subject based on the ideXlab platform.
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Modelling of Permeability and Mechanical Dispersion in a Porous Medium and Comparison with Experimental Measurements
Advanced Methods in Material Forming, 2020Co-Authors: Fabrice Loix, Vincent Thibaut, François DupretAbstract:A continuous model for the non-isothermal flow in a non-isotropic porous medium is presented and a Mechanical Dispersion model is proposed. An experimental device is set up in order to measure the permeability and Mechanical Dispersion components in a typical transversely isotropic cubic block consisting of polymeric needles. Finally, a micro-macro model for the flow of a Newtonian fluid in a porous medium is developed. The micro-model consists of a geometrical network of connectors and junctions. Integration and assembly of the equations provides a macroscopic model which obeys the Darcy or Forchheimer model depending on the dimensionless flow rate. Some peculiarities of the Brinkman model are addressed.
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Non-isothermal simulation of the resin transfer moulding press
Composites Part A: Applied Science and Manufacturing, 1998Co-Authors: A. Couniot, François DupretAbstract:The resin transfer moulding (RTM) of thin components is investigated by means of numerical simulation. The effect of Mechanical Dispersion in the gapwise direction is taken into account in the energy and species balances, while no mixing is considered along the midsurface. In a first model, incomplete mixing is considered in the gap, while perfect mixing is assumed in a second model. Several examples are analysed, which highlight the effect of Mechanical Dispersion on the general heat transfer. (C) 1997 Elsevier Science Limited
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Non-isothermal simulation of the resin transfer moulding process
Composites Part A: Applied Science and Manufacturing, 1998Co-Authors: O. Mal, A. Couniot, François DupretAbstract:The resin transfer moulding (RTM) of thin components is investigated by means of numerical simulation. The effect of Mechanical Dispersion in the gapwise direction is taken into account in the energy and species balances, while no mixing is considered along the midsurface. In a first model, incomplete mixing is considered in the gap, while perfect mixing is assumed in a second model. Several examples are analysed, which highlight the effect of Mechanical Dispersion on the general heat transfer. © 1997 Elsevier Science Limited.
Thor Edvardsen - One of the best experts on this subject based on the ideXlab platform.
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Impact of transcatheter aortic valve implantation on Mechanical Dispersion
Open heart, 2020Co-Authors: Lars Gunnar Klaeboe, Pål H Brekke, Lars Aaberge, Kristina Haugaa, Thor EdvardsenAbstract:Objectives: The physiological determinants of left ventricular (LV) Mechanical Dispersion (MD) are not fully explored. We aimed to investigate the impact of afterload reduction and changes in ventricular conduction on LV MD after transcatheter aortic valve implantation (TAVI). Methods: Patients with severe aortic stenosis (AS) were examined in a prospective, repeated measures observational cohort study before and after an uncomplicated transfemoral TAVI in a single tertiary centre. LV MD was assessed by speckle tracking echocardiography. Valvulo-arterial impedance (ZVA) was used as a measure of global afterload. Results: We included 140 consecutive patients (83±8 years old, 49% women, logistic EuroSCORE 16±10) with severe AS (valve area 0.7±0.2 cm2, mean transvalvular gradient 54±18 mm Hg) and a relatively preserved LV ejection fraction (52%±11%). After TAVI, we observed favourable changes in transvalvular gradients and ZVA in all patients. Compared with baseline, postprocedural MD was significantly lower in 108 patients with unchanged ventricular conduction (55±17 ms vs 51±17 ms, p=0.02) and higher in 28 patients with TAVI-induced left bundle branch block (51±13 ms vs 62±19 ms, p≤0.001). During 22±9 months observation, 22 patients died. Postprocedural MD was associated with mortality in a univariate Cox regression model (HR=1.24 (1.01-1.52), p
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prediction of ventricular arrhythmias with left ventricular Mechanical Dispersion a systematic review and meta analysis
Jacc-cardiovascular Imaging, 2020Co-Authors: Hiroshi Kawakami, Kristina H. Haugaa, Thor Edvardsen, Nitesh Nerlekar, Thomas H. MarwickAbstract:Abstract Objectives The aim of this study was to assess the association between left ventricular Mechanical Dispersion (LVMD) and the incidence of ventricular arrhythmias (VAs). Background Recent, mainly single-center, studies have demonstrated that LVMD assessed using speckle tracking might be a powerful marker in risk stratification for VA. A systematic review and meta-analysis provides a means of understanding the prognostic value of this parameter, relative to other parameters, the most appropriate cutoff for designating risk. Methods A systemic review of studies reporting the predictive value of LVMD for VA was undertaken from a search of MEDLINE and Embase. VA events were defined as sudden cardiac death, cardiac arrest, documented ventricular tachyarrhythmia, and appropriate implantable cardioverter-defibrillator (ICD) therapy. Hazard ratios were extracted from univariate and multivariate models reporting on the association of LVMD and VA and described as pooled estimates with 95% confidence intervals. In a meta-analysis, the predictive value of LVMD was compared with that of left ventricular ejection fraction and global longitudinal strain. Results Among 3,198 patients in 12 published studies, 387 (12%) had VA events over follow-up ranging from 17 to 70 months. Patients with VAs had greater LVMD than those without (weighted mean difference −20.3 ms; 95% confidence interval: −27.3 to −13.2; p Conclusions LVMD assessed using speckle tracking provides important predictive value for VA in patients with a number of cardiac diseases and appears to have superior predictive value over left ventricular ejection fraction and global longitudinal strain for risk stratification.
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P5976Prediction of ventricular arrhythmias with Mechanical Dispersion assessed by strain echocardiography: a systematic review and meta-analysis
European Heart Journal, 2019Co-Authors: H Kawakami, Kristina H. Haugaa, Thor Edvardsen, Nitesh Nerlekar, Thomas H. MarwickAbstract:Abstract Background Recent studies have demonstrated that left ventricular Mechanical Dispersion (LVMD) assessed by speckle tracking might be a powerful marker in risk stratification for ventricular arrhythmias (VA). We sought to perform a systematic review and meta-analysis to i) assess the prognostic value of this parameter (previous studies were predominantly single-center), ii) define the value relative to other parameters, iii) identify the most appropriate cutoff for designating risk. Purpose To assess the association between LVMD and the incidence of VA. Methods A systemic review of studies reporting the predictive value of LVMD for VA was undertaken from a search of Medline and Embase. LVMD was defined as the standard deviation of time from Q/R on ECG to peak negative strain from each LV segment. VA events were defined as sudden cardiac death, cardiac arrest, documented ventricular tachyarrhythmia, and appropriate implantable cardioverter defibrillator therapy. Hazard ratios (HRs) were extracted from univariable and multivariable models reporting on the association of LVMD and VA and described as pooled estimates with 95% confidence intervals (CIs). In a meta-analysis, the predictive value of LVMD was compared to that of left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS). Results Among 3198 patients (weighted mean, 63 years, 30% female; 82% ischemic heart disease) in 12 published articles, 387 (12%) had VA events over a follow-up (17–70 months). Patients with VA events had a significantly greater Mechanical Dispersion compared with those without VA events (weighted mean difference, −20.3 ms; 95% CI, −27.3 to −13.2; p<0.01); 60 ms was found to be the optimal cutoff LVMD value for predicting VA events. Each 10 ms increment of LVMD was significantly and independently associated with VA events (HR, 1.19; 95% CI, 1.09 to 1.29; p<0.01). The predictive value of LVMD was superior to that of LVEF or GLS (Figure). Figure 1 Conclusion LVMD assessed by speckle tracking provides important predictive value for VA in patients with a number of cardiac diseases and appears to have superior predictive value to LVEF and GLS for risk stratification.
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Prediction of Ventricular Arrhythmias With Left Ventricular Mechanical Dispersion: A Systematic Review and Meta-Analysis.
JACC. Cardiovascular imaging, 2019Co-Authors: Hiroshi Kawakami, Kristina H. Haugaa, Thor Edvardsen, Nitesh Nerlekar, Thomas H. MarwickAbstract:The aim of this study was to assess the association between left ventricular Mechanical Dispersion (LVMD) and the incidence of ventricular arrhythmias (VAs). Recent, mainly single-center, studies have demonstrated that LVMD assessed using speckle tracking might be a powerful marker in risk stratification for VA. A systematic review and meta-analysis provides a means of understanding the prognostic value of this parameter, relative to other parameters, the most appropriate cutoff for designating risk. A systemic review of studies reporting the predictive value of LVMD for VA was undertaken from a search of MEDLINE and Embase. VA events were defined as sudden cardiac death, cardiac arrest, documented ventricular tachyarrhythmia, and appropriate implantable cardioverter-defibrillator (ICD) therapy. Hazard ratios were extracted from univariate and multivariate models reporting on the association of LVMD and VA and described as pooled estimates with 95% confidence intervals. In a meta-analysis, the predictive value of LVMD was compared with that of left ventricular ejection fraction and global longitudinal strain. Among 3,198 patients in 12 published studies, 387 (12%) had VA events over follow-up ranging from 17 to 70 months. Patients with VAs had greater LVMD than those without (weighted mean difference -20.3 ms; 95% confidence interval: -27.3 to -13.2; p < 0.01). Each 10 ms increment of LVMD was significantly and independently associated with VA events (hazard ratio: 1.19; 95% confidence interval: 1.09 to 1.29; p < 0.01). The predictive value of LVMD was superior to that of left ventricular ejection fraction or global longitudinal strain. LVMD assessed using speckle tracking provides important predictive value for VA in patients with a number of cardiac diseases and appears to have superior predictive value over left ventricular ejection fraction and global longitudinal strain for risk stratification. Copyright © 2020 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
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Mechanical Dispersion as a marker of left ventricular dysfunction and prognosis in stable coronary artery disease.
International Journal of Cardiovascular Imaging, 2019Co-Authors: Brede Kvisvik, Kristina H. Haugaa, Erika Nerdrum Aagaard, Magnus Nakrem Lyngbakken, Marit Kristine Smedsrud, Lars Mørkrid, Helge Røsjø, Bjørn Bendz, Thor EdvardsenAbstract:Assessment of global longitudinal strain (GLS) is superior to ejection fraction (EF) in the evaluation of left ventricular (LV) function in patients with stable coronary artery disease (CAD). However, the role of Mechanical Dispersion (MD) in this context remains unresolved. We aimed to evaluate the potential role of MD as a marker of LV dysfunction and long-term prognosis in stable CAD. EF, GLS and MD were assessed in 160 patients with stable CAD, 1 year after successful coronary revascularization. Serum levels of high-sensitivity cardiac troponin I (hs-cTnI) and amino-terminal pro B-type natriuretic peptide (NT-proBNP) were quantified as surrogate markers of LV dysfunction. The primary endpoint was defined as all-cause mortality, the secondary endpoint was defined as the composite of all-cause mortality and hospitalization for acute myocardial infarction or heart failure during follow-up. Whereas no associations between EF and the biochemical markers of LV function were found, both GLS and MD correlated positively with increasing levels of hs-cTnI (R = 0.315, P