Search

BackgroundCardiac systolic dysfunction is a poor prognostic marker in light-chain (AL) cardiomyopathy, a primary interstitial disorder; however, its pathogenesis is poorly understood.PurposeThis study aims to analyze the effects of extracellular volume (ECV) expansion, a surrogate marker of amyloid burden on myocardial blood flow (MBF), myocardial work efficiency (MWE), and left ventricular (LV) systolic dysfunction in AL amyloidosis.MethodsSubjects with biopsy-proven AL amyloidosis were prospectively enrolled (April 2016–June 2021; Clinicaltrials.gov ID NCT02641145) and underwent cardiac magnetic resonance imaging (MRI) to quantify rest MBF by perfusion imaging, LV ejection fraction (LVEF) by cine MRI, and ECV by pre- and post-contrast T1 mapping. The MWE was estimated as external cardiac work from the stroke volume and mean arterial pressure normalized to the LV myocardial mass.ResultsRest MBF in 92 subjects (62 ± 8 years, 52 men) with AL amyloidosis averaged 0.87 ± 0.21 ml/min/g and correlated with MWE (r = 0.42; p

Not much is known about the effects of sodium-glucose cotransporter 2 inhibitors (SGLT2i) on echocardiographic parameters of left ventricular (LV) systolic function in patients with heart failure and reduced ejection fraction (HFrEF). We prospectively included 59 outpatients with HFrEF: 41 patients received SGLT2i with OMT (SGLT2i+ group), whereas eighteen patients received OMT without SGLT2i (SGLT2i− group). Myocardial work index (MWI), 3D ejection fraction (3D LVEF), and global longitudinal strain (GLS) were measured at baseline and after 3 months following treatment. At 3-month follow-up, the SGLT2i+ group showed significantly greater improvement in MWI than the SGLT2i− group. In both groups, there was a significant improvement in 3D LVEF and LV GLS, circulating NT-proBNP levels, and NYHA functional class, with significantly greater improvement in the SGLT2i+ group. In conclusion, the addition of SGLT2i to fully optimized background medical therapy resulted in a greater improvement of LV systolic function among outpatients with HFrEF. [ABSTRACT FROM AUTHOR]

In echocardiography, peak strain dispersion (PSD) is the standard deviation of the time to peak longitudinal strain for each left ventricular (LV) segment during systole. It assesses the coordination and synchrony of LV segment contractility. Global work efficiency (GWE) and global wasted work (GWW) quantify LV myocardial work and, if impaired, the coupling between LV systolic contraction and early relaxation. Isovolumetric relaxation (IVRT) measures the duration of initial LV relaxation, while the ratio of early diastolic recoil to systolic excursion (E′VTI/S′VTI) describes systolic–diastolic coupling. We evaluated these parameters in 69 healthy subjects and found that PSD correlated negatively with GWE (r = −0.49, p < 0.0001) and E′VTI/S′VTI (r = −0.44, p = 0.0002), but positively with GWW (r = 0.4, p = 0.0007) and IVRT (r = 0.53, p < 0.0001). GWE correlated negatively with GWW (r = −0.94, p < 0.0001) and IVRT (r = −0.30, p = 0.0127), but positively with E′VTI/S′VTI (r = 0.3, p = 0.0132). In addition, E′VTI/S′VTI was negatively correlated with GWW (r = −0.35, p = 0.0032) and IVRT (r = −0.36, p = 0.0024). These associations remained significant after adjustment for sex, age and LV mass index of the subjects. In conclusion, there is an interaction between measures of LV asynchrony, myocardial work, diastolic function and its systolic–diastolic coupling in middle-aged healthy subjects. The clinical value of these interactions requires further investigation. [ABSTRACT FROM AUTHOR]

BackgroundLeft bundle branch pacing (LBBP) is an emerging physiological pacing modality. Left ventricular (LV) myocardial work (MW) incorporates afterload and LV global longitudinal strain to estimate global and segmental myocardial contractility. However, the effect of LBBP on LV MW remains unknown. This study aimed to evaluate the impact of LBBP on LV MW in patients receiving pacemaker for bradyarrhythmia.MethodsWe prospectively enrolled 70 bradycardia patients with normal LV systolic function receiving LBBP (n = 46) and non-selective His-bundle pacing (NS-HBP) (n = 24). For comparative analysis, patients receiving right ventricular pacing (RVP) (n = 16) and control subjects (n = 10) were enrolled. Two-dimensional speckle tracking echocardiography was performed. The LV pressure-strain loop was non-invasively constructed to assess global LV MW.ResultsAfter 6-month follow-up, LBBP group (with >40% ventricular pacing during 6 months) had shorter peak strain dispersion (PSD) compared with RVP group, and higher LV global longitudinal strain compared with RVP group and NS-HBP group, but had no difference in left intraventricular mechanical dyssynchrony, including septal-to-posterior wall motion delay and PSD, compared with NS-HBP group. During ventricular pacing, LBBP group had higher global MW index (GWI) (2,189 ± 527 vs. 1,493 ± 799 mmHg%, P = 0.002), higher global constructive work (GCW) (2,921 ± 771 vs. 2,203 ± 866 mmHg%, P = 0.009), lower global wasted work (GWW) (211 ± 161 vs. 484 ± 281 mmHg%, P 40%), LBBP preserved more LV MW compared with NS-HBP and RVP. Further studies are warranted to assess the association between LV MW and long-term clinical outcomes in LBBP with high ventricular pacing burden.

BackgroundMyocardial layer-specific strain can identify myocardial ischemia. Global myocardial work efficiency (GWE) based on non-invasive left ventricular (LV) pressure-strain loops is a novel parameter to determine LV function considering afterload. The study aimed to compare the diagnostic value of GWE and myocardial layer-specific strain during treadmill exercise stress testing to detect significant coronary artery disease (CAD) with normal baseline wall motion.MethodsEighty-nine patients who referred for coronary angiography due to suspected of CAD were included. Forty patients with severe coronary artery stenosis were diagnosed with significant CAD, and 49 were defined as non-significant CAD. Stress echocardiography was performed 24 h before angiography. Layer-specific longitudinal strains were assessed from the endocardium, mid-myocardium, and epicardium by 2D speckle-tracking echocardiography. Binary logistic regression analyses were performed to evaluate the association between significant CAD and echocardiographic parameters. A receiver operating characteristic curve was used to assess the capability of layer-specific strain and GWE to diagnose significant CAD.ResultsPatients with significant CAD had the worse function in all three myocardial layers at peak exercise compared with those with non-significant CAD when assessed with global longitudinal strain (GLS). At the peak exercise and recovery periods, GWE was lower in patients with significant CAD than in patients with non-significant CAD. In multivariable binary logistic regression analysis, peak endocardial GLS (OR: 1.35, p = 0.006) and peak GWE (OR: 0.76, p = 0.001) were associated with significant CAD. Receiver operating characteristic curves showed peak GWE to be superior to mid-myocardial, epicardial, and endocardial GLS in identifying significant CAD. Further, adding peak GWE to endocardial GLS could improve diagnostic capabilities.ConclusionsBoth GWE and endocardial GLS contribute to improving the diagnostic performance of exercise stress echocardiography. Furthermore, adding peak GWE to peak endocardial GLS provides incremental diagnostic value during a non-invasive screening of significant CAD before radioactive or invasive examinations.

Introduction: Left ventricular (LV) dilatation and LV hypertrophy are acknowledged precursors of myocardial dysfunction and ultimately of heart failure, but the implications of abnormal LV geometry on myocardial function are not well-understood. Non-invasive LV myocardial work (MyW) assessment based on echocardiography-derived pressure-strain loops offers the opportunity to study detailed myocardial function in larger cohorts. We aimed to assess the relationship of LV geometry with MyW indices in general population free from heart failure.Methods and Results: We report cross-sectional baseline data from the Characteristics and Course of Heart Failure Stages A-B and Determinants of Progression (STAAB) cohort study investigating a representative sample of the general population of Würzburg, Germany, aged 30–79 years. MyW analysis was performed in 1,926 individuals who were in sinus rhythm and free from valvular disease (49.3% female, 54 ± 12 years). In multivariable regression, higher LV volume was associated with higher global wasted work (GWW) (+0.5 mmHg% per mL/m2, p < 0.001) and lower global work efficiency (GWE) (−0.02% per mL/m2, p < 0.01), while higher LV mass was associated with higher GWW (+0.45 mmHg% per g/m2, p < 0.001) and global constructive work (GCW) (+2.05 mmHg% per g/m2, p < 0.01) and lower GWE (−0.015% per g/m2, p < 0.001). This was dominated by the blood pressure level and also observed in participants with normal LV geometry and concomitant hypertension.Conclusion: Abnormal LV geometric profiles were associated with a higher amount of wasted work, which translated into reduced work efficiency. The pattern of a disproportionate increase in GWW with higher LV mass might be an early sign of hypertensive heart disease.

Non-ST-segment-elevation acute coronary syndrome (NSTE-ACS) patients with normal left ventricular (LV) ejection fraction (LVEF) and wall motion require a non-invasive tool to detect LV risk areas. This study utilized non-invasive LV pressure–strain loops to evaluate territorial myocardial work efficiency (WE) for identifying obstructive coronary artery stenosis, in patients with non-obstructive or obstructive coronary artery stenosis NSTE-ACS, the latter with or without occlusion. Global and territorial longitudinal strain (LS) analyses were performed via speckle-tracking imaging before coronary angiography. LV pressure–strain loops estimated global and territorial myocardial work index (MWI), constructive work (CW), wasted work (WW), and WE. Receiver operating characteristic curve analysis was used to determine the optimal cutoff value of independent parameters to detect obstructive coronary artery stenosis. Compared with non-obstructive, obstructive coronary artery stenosis showed significantly lower global and territorial LS, MWI, CW, and WE, and higher WW. Territorial LS, MWI, CW, and WE were significantly worse in territories of coronary occlusion. Territorial WE was the best parameter for predicting obstructive coronary artery stenosis (AUC 0.80, cutoff < 96%, sensitivity 73%, specificity 70%, P < 0.001). In patients with NSTE-ACS with normal wall motion and LVEF, territorial WE is more accurate than territorial LS or MWI to identify LV risk areas. [ABSTRACT FROM AUTHOR]

Background: Cardiac systolic dysfunction is a poor prognostic marker in light-chain (AL) cardiomyopathy, a primary interstitial disorder; however, its pathogenesis is poorly understood., Purpose: This study aims to analyze the effects of extracellular volume (ECV) expansion, a surrogate marker of amyloid burden on myocardial blood flow (MBF), myocardial work efficiency (MWE), and left ventricular (LV) systolic dysfunction in AL amyloidosis., Methods: Subjects with biopsy-proven AL amyloidosis were prospectively enrolled (April 2016-June 2021; Clinicaltrials.gov ID NCT02641145) and underwent cardiac magnetic resonance imaging (MRI) to quantify rest MBF by perfusion imaging, LV ejection fraction (LVEF) by cine MRI, and ECV by pre- and post-contrast T1 mapping. The MWE was estimated as external cardiac work from the stroke volume and mean arterial pressure normalized to the LV myocardial mass., Results: Rest MBF in 92 subjects (62 ± 8 years, 52 men) with AL amyloidosis averaged 0.87 ± 0.21 ml/min/g and correlated with MWE ( r  = 0.42; p  < 0.001). Rest MBF was similarly low in subjects with sustained hematologic remission after successful AL amyloidosis therapy ( n  = 21), as in those with recently diagnosed AL amyloidosis. Both MBF and MWE decreased by ECV tertile ( p  < 0.01 for linear trends). The association of ECV with MWE comprised a direct effect (84% of the total effect; p  < 0.001) on MWE from adverse interstitial remodeling assessed by ECV and an indirect effect (16% of the total effect; p  < 0.001) mediated by MBF. There was a significant base-to-apex gradient of rest MBF in subjects with higher amyloid burden., Conclusions: In AL amyloidosis, both MBF and MWE decrease as cardiac amyloid burden and ECV expansion increase. Both structural and vascular changes from ECV expansion and myocardial amyloid burden appear to contribute to lower MWE., Competing Interests: SC: investigator—initiated a research grant from Pfizer. FR: consulting fees—Pfizer, AstraZeneca, Attralus; research support—Pfizer, Alnylam Pharmaceuticals, Akcea Therapeutics. MDC: research grant—Spectrum Dynamics and Gilead; consulting fees—Sanofi and GE HealthCare. RF: consulting fees—Ionis Pharmaceuticals, Alnylam Pharmaceuticals, and Caelum Biosciences; research funding—GlaxoSmithKline and Akcea. SD: consulting fees—Pfizer, GE HealthCare, and AstraZeneca; investigator—initiated a grant from Pfizer, Attralus, Phillips, and Siemens. OC: research fellowship from the International Society of Amyloidosis and Pfizer. AY: consulting fees—AbbVie, Adaptive Biotechnologies, Amgen, BMS, Celgene, GSK Janssen, Karyopharm, Oncopeptides, Regeneron, Sanofi, and Takeda. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2024 Katznelson, Jerosch-Herold, Cuddy, Clerc, Benz, Taylor, Rao, Kijewski, Liao, Landau, Yee, Ruberg, Di Carli, Falk, Kwong and Dorbala.)

Background: Left bundle branch pacing (LBBP) is an emerging physiological pacing modality. Left ventricular (LV) myocardial work (MW) incorporates afterload and LV global longitudinal strain to estimate global and segmental myocardial contractility. However, the effect of LBBP on LV MW remains unknown. This study aimed to evaluate the impact of LBBP on LV MW in patients receiving pacemaker for bradyarrhythmia., Methods: We prospectively enrolled 70 bradycardia patients with normal LV systolic function receiving LBBP ( n  = 46) and non-selective His-bundle pacing (NS-HBP) ( n  = 24). For comparative analysis, patients receiving right ventricular pacing (RVP) ( n  = 16) and control subjects ( n  = 10) were enrolled. Two-dimensional speckle tracking echocardiography was performed. The LV pressure-strain loop was non-invasively constructed to assess global LV MW., Results: After 6-month follow-up, LBBP group (with >40% ventricular pacing during 6 months) had shorter peak strain dispersion (PSD) compared with RVP group, and higher LV global longitudinal strain compared with RVP group and NS-HBP group, but had no difference in left intraventricular mechanical dyssynchrony, including septal-to-posterior wall motion delay and PSD, compared with NS-HBP group. During ventricular pacing, LBBP group had higher global MW index (GWI) (2,189 ± 527 vs. 1,493 ± 799 mmHg%, P  = 0.002), higher global constructive work (GCW) (2,921 ± 771 vs. 2,203 ± 866 mmHg%, P  = 0.009), lower global wasted work (GWW) (211 ± 161 vs. 484 ± 281 mmHg%, P  < 0.001) and higher global MW efficiency (GWE) (91.4 ± 5.0 vs. 80.9 ± 8.3%, P  < 0.001) compared with RVP group, and had lower GWW (211 ± 161 vs. 406 ± 234 mmHg%, P  < 0.001) and higher GWE (91.4 ± 5.0 vs. 86.4 ± 8.1%, P  < 0.001) compared with NS-HBP group., Conclusions: In this study we found that in patients with mid-term (6-month) high ventricular pacing burden (>40%), LBBP preserved more LV MW compared with NS-HBP and RVP. Further studies are warranted to assess the association between LV MW and long-term clinical outcomes in LBBP with high ventricular pacing burden., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Chen, Liu, Chen, Lee, Fang, Chong and Chen.)

Background: Myocardial layer-specific strain can identify myocardial ischemia. Global myocardial work efficiency (GWE) based on non-invasive left ventricular (LV) pressure-strain loops is a novel parameter to determine LV function considering afterload. The study aimed to compare the diagnostic value of GWE and myocardial layer-specific strain during treadmill exercise stress testing to detect significant coronary artery disease (CAD) with normal baseline wall motion., Methods: Eighty-nine patients who referred for coronary angiography due to suspected of CAD were included. Forty patients with severe coronary artery stenosis were diagnosed with significant CAD, and 49 were defined as non-significant CAD. Stress echocardiography was performed 24 h before angiography. Layer-specific longitudinal strains were assessed from the endocardium, mid-myocardium, and epicardium by 2D speckle-tracking echocardiography. Binary logistic regression analyses were performed to evaluate the association between significant CAD and echocardiographic parameters. A receiver operating characteristic curve was used to assess the capability of layer-specific strain and GWE to diagnose significant CAD., Results: Patients with significant CAD had the worse function in all three myocardial layers at peak exercise compared with those with non-significant CAD when assessed with global longitudinal strain (GLS). At the peak exercise and recovery periods, GWE was lower in patients with significant CAD than in patients with non-significant CAD. In multivariable binary logistic regression analysis, peak endocardial GLS (OR: 1.35, p = 0.006) and peak GWE (OR: 0.76, p = 0.001) were associated with significant CAD. Receiver operating characteristic curves showed peak GWE to be superior to mid-myocardial, epicardial, and endocardial GLS in identifying significant CAD. Further, adding peak GWE to endocardial GLS could improve diagnostic capabilities., Conclusions: Both GWE and endocardial GLS contribute to improving the diagnostic performance of exercise stress echocardiography. Furthermore, adding peak GWE to peak endocardial GLS provides incremental diagnostic value during a non-invasive screening of significant CAD before radioactive or invasive examinations., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Lin, Gao, He, Liu, Cai, Niu, Zhao, Li, Wang, Wu, Zhu and Wang.)

Introduction: Left ventricular (LV) dilatation and LV hypertrophy are acknowledged precursors of myocardial dysfunction and ultimately of heart failure, but the implications of abnormal LV geometry on myocardial function are not well-understood. Non-invasive LV myocardial work (MyW) assessment based on echocardiography-derived pressure-strain loops offers the opportunity to study detailed myocardial function in larger cohorts. We aimed to assess the relationship of LV geometry with MyW indices in general population free from heart failure. Methods and Results: We report cross-sectional baseline data from the Characteristics and Course of Heart Failure Stages A-B and Determinants of Progression (STAAB) cohort study investigating a representative sample of the general population of Würzburg, Germany, aged 30-79 years. MyW analysis was performed in 1,926 individuals who were in sinus rhythm and free from valvular disease (49.3% female, 54 ± 12 years). In multivariable regression, higher LV volume was associated with higher global wasted work (GWW) (+0.5 mmHg% per mL/m 2 , p < 0.001) and lower global work efficiency (GWE) (-0.02% per mL/m 2 , p < 0.01), while higher LV mass was associated with higher GWW (+0.45 mmHg% per g/m 2 , p < 0.001) and global constructive work (GCW) (+2.05 mmHg% per g/m 2 , p < 0.01) and lower GWE (-0.015% per g/m 2 , p < 0.001). This was dominated by the blood pressure level and also observed in participants with normal LV geometry and concomitant hypertension. Conclusion: Abnormal LV geometric profiles were associated with a higher amount of wasted work, which translated into reduced work efficiency. The pattern of a disproportionate increase in GWW with higher LV mass might be an early sign of hypertensive heart disease., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Sahiti, Morbach, Cejka, Albert, Eichner, Gelbrich, Heuschmann and Störk.)

Background: Myocardial work index (MWI) and work efficiency are new parameters for assessing left ventricular function. We aim to characterize the normal response to exercise in a mixed population and determine whether MWI can identify patients with inducible ischemia., Methods: Patients were retrospectively enrolled from an existing database of exercise stress echocardiography. Inclusion criteria were a clinical indication of possible ischemia and technical suitability to calculate MWI. Exclusion criteria were abnormal baseline left ventricular function or inadequate image quality. Echocardiograms positive for ischemia were defined by independent visual assessment and compared with angiographic findings where available. Myocardial work index was determined using a proprietary algorithm and efficiency calculated as constructive work divided by the sum of constructive and wasted work., Results: A total of 177 patients met inclusion criteria; 117 were excluded, leaving 40 normal and 20 positive tests. During normal exercise, global MWI increased 54% (from 2,296 to 3,523 mm Hg%) and efficiency remained at 96%. However, in patients with inducible ischemia, MWI decreased in affected segments, global MWI did not increase (2,069-2,070 mm Hg%), and global efficiency fell from 93% to 87%. The receiver operating characteristic curve for MWI had an area under the curve of 0.94., Conclusions: During normal exercise, MWI increases and efficiency remains unchanged. However, during exercise-induced ischemia, MWI paradoxically decreases in affected segments, while globally MWI fails to increase and efficiency decreases. We have demonstrated that MWI can be applied to stress echocardiography to identify ischemia, but its utility remains uncertain. Further research that makes comparisons with an objective measure of functional ischemia is needed., (Copyright © 2020 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.)

Background: Global left ventricular (LV) myocardial work efficiency, the ratio of constructive to wasted work in all LV segments, reflects the efficiency by which mechanical energy is expended during the cardiac cycle. Global LV myocardial work efficiency can be derived from LV pressure-strain loop analysis incorporating both noninvasively estimated blood pressure recordings and echocardiographic strain data. The aim of this study was to characterize global LV myocardial work efficiency in healthy individuals and patients with cardiovascular (CV) risk factors or overt cardiac disease., Methods: We retrospectively included healthy individuals without structural heart disease or CV risk factors, who were selected from an ongoing database of normal individuals, and matched for age and sex with (1) individuals without structural heart disease but with CV risk factors, (2) postinfarct patients without heart failure, and (3) heart failure patients with reduced ejection fraction (HFrEF). Global LV myocardial work efficiency was estimated with a proprietary algorithm from speckle-tracking strain analyses, as well as noninvasive blood pressure measurements., Results: In total, 120 individuals (44% male, 53 ± 13 years) were included (n = 30 per group). In healthy individuals without structural heart disease or CV risk factors, global LV myocardial work efficiency was 96.0% (interquartile range, 95.0%-96.3%). Myocardial efficiency of the LV did not differ significantly between individuals without structural heart disease and those with CV risk factors (96.0% vs 96.0%; P = .589). Global LV myocardial work efficiency, however, was significantly decreased in postinfarct patients (96.0% vs 93.0%, P < .001) and in those with HFrEF (96.0% vs 69.0%; P < .001)., Conclusions: While global LV myocardial work efficiency was similar in normal individuals and in those with CV risk factors, it was decreased in postinfarct and HFrEF patients. The global LV myocardial work efficiency values presented here show distinct patterns in different cardiac pathologies., (Copyright © 2019 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.)