A study on the correlation between lung injury severity and cardiac function through a closed-loop model

OBJECTIVE

Numerous clinical and pathological studies have confirmed that lung injury can cause cardiovascular disease, but there is no explanation for the mechanism by which the degree of lung injury affects cardiac function. We attempt to reveal this mechanism of influence by simulating a cyclic model.

METHOD

This study established a closed-loop cardiovascular model with a series of electrical parameters. Including the heart, lungs, arteries, veins, etc., each part of the cardiovascular system is modeled using centralized parameters. Adjusting these lung resistances to alter the degree of lung injury is aimed at reflecting the impact of different degrees of lung injury on cardiac function. Finally, analyze and compare the changes in blood pressure, aortic flow, atrioventricular volume, and atrioventricular pressure among different lung injuries to obtain the changes in cardiac function.

RESULTS

In this model, the peak aortic flow decreased, the earlier the trough appeared, and the total aortic flow decreased. Left atrial blood pressure decreased from 6.5 mmHg to around 5.5 mmHg, left ventricular blood pressure decreased from 100 mmHg to around 50 mmHg, and aortic blood pressure also decreased from 100 mmHg to around 50 mmHg. The blood pressure in the pulmonary artery, right atrium, and right ventricle increases. The right ventricular blood pressure decreased from 20 mmHg to around 40 mmHg, while the right atrial blood pressure slightly increased. It can be seen that the increase in impedance has a greater impact on ventricular blood pressure than on atrium. Pulmonary arterial pressure significantly increases, rising from 20 mmHg to around 50 mmHg, forming pulmonary hypertension. The left ventricular end-systolic potential energy, filling energy, stroke work, stroke output, left ventricular filling period, maximum blood pressure during ventricular ejection period, and stroke energy efficiency decrease.

CONCLUSION

We established a closed-loop cardiovascular model that reveals that the more severe lung injury, the higher blood pressure in the pulmonary artery, right atrium, and right ventricle, while the lower blood pressure in the left atrium, left ventricle, and aorta. The increase in pulmonary impedance leads to abnormalities in myocardial contraction, diastolic function, and cardiac reserve capacity, leading to a decrease in cardiac function. This closed-loop model provides a method for pre assessment of cardiovascular disease after lung injury.

Global longitudinal strain by cardiac magnetic resonance is associated with cardiac iron and complications in beta-thalassemia major patients

BACKGROUND

The aim of this cross-sectional study was to investigate the association of left ventricular (LV) strain parameters with demographics, clinical data, cardiovascular magnetic resonance (CMR) findings, and cardiac complications (heart failure and arrhythmias) in patients with β-thalassemia major (β-TM).

METHOD

We considered 266 β-TM patients (134 females, 37.08 ± 11.60 years) consecutively enrolled in the Extension-Myocardial Iron Overload in Thalassemia (E-MIOT) project and 80 healthy controls (50 females, mean age 39.77 ± 11.29 years). The CMR protocol included cine images for the assessment of global longitudinal strain (GLS), global circumferential strain (GCS), and global radial strain (GRS) using feature tracking (FT) and for the quantification of LV function parameters, the T2* technique for the assessment of myocardial iron overload, and late gadolinium enhancement (LGE) technique.

RESULTS

In comparison to the healthy control group, β-TM patients showed impaired GLS, GCS, and GRS values. Among β-TM patients, sex was identified as the sole independent determinant of all LV strain parameters. All LV strain parameters displayed a significant correlation with LV end-diastolic volume index, end-systolic volume index, mass index, and ejection fraction, and with the number of segments exhibiting LGE. Only GLS exhibited a significant correlation with global heart T2* values and the number of segments with T2* < 20 ms. Patients with cardiac complications exhibited significantly impaired GLS compared to those without cardiac complications.

CONCLUSION

In patients with β-TM, GLS, GCS, and GRS were impaired in comparison with control subjects. Among LV strain parameters, only GLS demonstrated a significant association with cardiac iron levels and complications.

Global left ventricular myocardial work: A novel method to assess left ventricular myocardial function and predict major adverse cardiovascular events in maintenance hemodialysis patients

BACKGROUND

The application value of myocardial work (MW) in evaluating myocardial function and predicting major adverse cardiovascular events (MACE) in maintenance hemodialysis (MHD) patients has not been fully explored.

PURPOSE

Comparing noninvasive MW parameters between MHD patients and healthy controls, and further determining its value in predicting MACE in MHD patients.

METHODS

A prospective single-institution study included 92 MHD patients without prior cardiovascular disease and 40 age- and sex-matched healthy controls. Conventional echocardiographic data, global longitudinal strain (GLS), and MW parameters (global work index [GWI], global constructive work [GCW], global work efficiency [GWE], global wasted work [GWW]) were derived and compared between MHD and the control. Logistic regression was used to determine the predictive value of these parameters for MACE. The receiver operating characteristic curve was utilized to compare the predictive differences of MACE between GWE and GLS.

RESULTS

Compared with healthy individuals, MHD patients had significantly reduced GWE, GLS and elevated LVMI, GWW (all p < 0.001), while there was no significant difference in left ventricular ejection fraction. Twenty eight (30%) MHD patients experienced MACE. Two nested models adding GWE and GLS, respectively, showed that age (p < 0.005), GWE (p = 0.034), and GLS (p = 0.014) were independent predictors of MACE. The AUC derived from GWE for predicting MACE was significantly higher than that derived from GLS (0.836 vs. 0.743, p = 0.039).

CONCLUSIONS

Myocardial work is a novel tool for assessing left ventricular myocardial performance in MHD patients. GWE is an independent predictor of MACE.

Usability of myocardial work parameters in demonstrating myocardial involvement in INOCA patients

BACKGROUND

Myocardial work (MW) is a novel echocardiographic modality, which has been shown to have diagnostic and prognostic values in patients with cardiovascular diseases, patients with obstructive coronary artery disease, in particular. However, only a handful of studies have examined the MW analysis in ischemia with nonobstructive coronary artery (INOCA) disease. This study, therefore, aimed to detect the early left ventricular involvement in INOCA patients diagnosed by an invasive coronary angiography performing the MW analysis.

METHODS

This study included a total of 119 patients with nonobstructive coronary artery disease diagnosed by invasive coronary angiography, who were checked for prior ischemia tests performing myocardial perfusion scintigraphy. Out of these 119 patients, 49 patients developed ischemia (i.e., ischemic group) diagnosed using cardiac single-photon emission computed tomography, whereas 70 patients did not (i.e., nonischemic group). The subjects were divided into three groups based on the global MW tertiles. The groups were compared in terms of the conventional, longitudinal strain, and MW findings by conducting echocardiographic examinations.

RESULTS

The study subjects were divided into three groups based on the global constrictive work (GCW) value. The three groups were not statistically different in terms of the mean age of the patients (53.0 ± 12 vs. 52.4 ± 13.3 vs. 52.1 ± 12.3; p = 0.96). Furthermore, the three groups were not statistically different regarding the gender, height, weight, and laboratory parameters of the patients except albumin. There was no statistically difference among the tertiles of GCW groups in the measurements of cardiac chambers, LA diameter, interventricular septum, E wave, and A wave. Also, there was no statistical difference in tissue Doppler recordings. The parameters associated with MW were examined, three groups were not statistically different in terms of the global waste work (GWW) (116 ± 92, 122 ± 73, 135 ± 62, p = 0.52, respectively). In contrast, the three groups were different regarding the Global work index (GWI) (1716 ± 300, 1999 ± 130, 2253 ± 195, p < 0.001, respectively), GCW (1888 ± 206, 2298 ± 75, 2614 ± 155, p < 0.001, respectively), and Global work efficiency parameters (92.8 ± 3.6, 94.4 ± 3.2, 95.1 ± 1.8 p = 0.004, respectively).

CONCLUSION

It was concluded that the MW parameters GCW and GWI may have been used for predicting INOCA in patients.

Left Ventricle Myocardial Work Correlated with Functional Capacity in Severe Rheumatic Mitral Stenosis with Preserved Left Ventricular Ejection Fraction

Background and Aims

Functional capacity is reduced in mitral stenosis (MS) patients. Previous studies showed a correlation between left atrial strain and functional capacity in this population. However, currently, no left ventricle (LV) echocardiographic parameters were associated with functional capacity in patients with MS. Noninvasive LV pressure-strain loop analysis is a new echocardiographic method for evaluating LV function, integrating longitudinal strain from speckle-tracking analysis and noninvasively measured blood pressure to estimate myocardial work (MW) that overcomes the preload-dependent characteristics conventional parameters by integrating afterload. This study aimed to evaluate the association between MW and functional capacity measured using exercise tests in patients with severe MS and preserved LV ejection fraction (LVEF).

Methods

Adult patients with symptomatic severe rheumatic MS (mitral valve area <1.5 cm2), and preserved LVEF (>50%) and sinus rhythm who underwent echocardiography and exercise stress test in our hospital from 2019 to 2021 were included. Exclusion criteria were suboptimal image quality for myocardial deformation analysis, significant mitral regurgitation or aortic valve lesions, coronary artery disease, intracardiac shunt, and atrial fibrillation. Standard echocardiographic parameters were measured, and all MW parameters were included. Exercise treadmill testing was performed using the modified Bruce protocol.

Results

A total of 33 individuals with isolated severe rheumatic MS in sinus rhythm (age 39.8 ± 9.8 years) were included in the study. Patients with severe isolated MS showed significantly impaired LV-global longitudinal strain values compared to normal reference values. Furthermore, patients with severe MS showed significantly lower values of global work index, global constructive work, and efficiency compared to normal values and higher wasted work. Global work efficiency was significantly correlated to the duration of exercise (P = 0.025, Pearson's r = 0.389).

Conclusions

In stable patients with isolated severe mitral stenosis, MW efficiency significantly correlated with functional capacity measured objectively through exercise testing.

Left ventricular global work index and prediction of cardiovascular mortality after transcatheter aortic valve implantation

INTRODUCTION

Echocardiography is used for assessment of patients after transcatheter aortic valve implantation (TAVI). Global work index (GWI) integrates LV deformation throughout the cardiac cycle and LV afterload and may be advantageous for long-term follow-up.

METHODS

We analysed 144 patients with severe aortic stenosis who underwent TAVI and echocardiography within two weeks afterwards. GE EchoPAC v2.6 was applied for determining LV ejection fraction, global longitudinal strain (GLS), stroke work (SW), cardiac power output (CPO), and GWI. The endpoint was cardiovascular mortality.

RESULTS

During median follow-up of 625 [IQR: 511-770] days, 20 (14%) patients died. Clinical baseline characteristics were comparable between non-survivors and survivors. GWI (p = 0.003) and LVEF (p = 0.039) were lower in non-survivors, while GLS, SW, and CPO were not different. In Kaplan-Meier analysis patients with GWI ≤1234 mmHg% exhibited a lower survival probability (P = 0.006). In univariable Cox regression, a significant mortality association was identified for GWI (P = 0.004), weaker for LVEF (P = 0.014), but not for the other parameters. In multivariable Cox regression, GWI independently improved an LV systolic function model including LVEF and GLS. Similarly, GWI but not LVEF independently improved outcome association of different clinical models.

CONCLUSIONS

GWI was lower in non-survivors than survivors, differentiated non-survivors from survivors, was associated with mortality independent of clinical or LV parameters, and improved the fitness of clinical or LV prediction models. In contrast, GLS, SW, and CPO did not show any of these properties. GWI provides added value for follow-up after TAVI possibly by integrating LV deformation throughout the cardiac cycle.

Association between myocardial work indices and cardiovascular events according to hypertension in the general population

AIMS

Pressure-strain loop (PSL) analysis is a novel echocardiographic tool capable of assessing myocardial work non-invasively. In this study, we aim to evaluate the prognostic value of myocardial work indices in the general population.

METHODS AND RESULTS

This was a prospective community-based cohort study (n = 4466). PSL analyses were performed to acquire global work index (GWI), global constructive work (GCW), global wasted work, and global work efficiency (GWE). The endpoint was a composite of heart failure or cardiovascular death (HF/CVD). Survival analysis was applied. A total of 3932 participants were included in this analysis (median age: 58 years, 43% men). Of these, 124 (3%) experienced the outcome during a median follow-up period of 3.5 years [interquartile range (IQR): 2.6-4.4 years]. Hypertension significantly modified the association between all work indices and outcome (P for interaction < 0.05), such that work indices posed a higher risk of outcome in non-hypertensive than in hypertensive participants. After adjusting for Atherosclerosis Risk in Communities (ARIC)-HF risk variables, all work indices predicted outcome in non-hypertensive participants, but only GWI, GCW, and GWE predicted outcome in hypertensive participants [GWI: hazard ratio (HR) = 1.12 (1.07-1.16), per 100 mmHg% decrease; GCW: HR = 1.12 (1.08-1.17), per 100 mmHg% decrease; GWE: HR = 1.08 (1.04-1.12), per 1% decrease]. Only GWE significantly increased C-statistics when added to ARIC-HF risk variables in hypertensive participants (C-stat 0.865 vs. 0.877, P for increment = 0.003).

CONCLUSION

Hypertension modifies the association between myocardial work indices and HF/CVD in the general population. All work indices are associated with outcome in normotensive participants. GWI, GCW, and GWE are independently associated with outcome in hypertension, but only GWE improves risk prediction.

A novel speckle-tracking echocardiography parameter assessing left ventricular afterload

BACKGROUND

Left ventricular stroke work index (LVSWI) and afterload-related cardiac performance (ACP) consider left ventricular (LV) afterload and could be better prognosticators in septic cardiomyopathy. However, their invasive nature prevents their routine clinical applications. This study aimed to investigate (1) whether a proposed speckle-tracking echocardiography parameter, Pressure-Strain Product (PSP), can non-invasively predict catheter-based LVSWI, ACP and serum lactate in an ovine model of septic cardiomyopathy; and (2) whether PSP can distinguish the sub-phenotypes of acute respiratory distress syndrome (ARDS) with or without sepsis-like conditions.

METHODS

Sixteen sheep with ARDS were randomly assigned to either (1) sepsis-like (n = 8) or (2) non-sepsis-like (n = 8) group. Each ARDS and sepsis-like condition was induced by intravenous infusion of oleic acid and lipopolysaccharide, respectively. Pulmonary artery catheter-based LVSWI (the product of stroke work index, mean arterial pressure and .0136), ACP (the percentage of cardiac output measured to cardiac output predicted as normal) and serum lactate were measured simultaneously with transthoracic echocardiography. Two PSP indices were calculated by multiplying the mean arterial blood pressure and either global circumferential strain (PSPcirc) or radial strain (PSPrad).

RESULTS

PSPcirc showed a significant correlation with LVSWI (r2  = .66, p < .001) and ACP (r2  = .82, p < .001) in the sepsis-like group. Although PSP could not distinguish subphenotypes, PSPcirc predicted LVSWI (AUC .86) and ACP (AUC .88), and PSPrad predicted serum lactate (AUC .75) better than LV ejection fraction, global circumferential and radial strain.

CONCLUSIONS

A novel PSP has the potential to non-invasively predict catheter-based LVSWI and ACP, and was associated with serum lactate in septic cardiomyopathy.

Non-invasive myocardial work in aortic stenosis: validation and improvement in left ventricular pressure estimation

AIMS

The non-invasive myocardial work index (MWI) has been validated in patients without aortic stenosis (AS). A thorough assessment of methodological limitations is warranted before this index can be applied to patients with AS.

METHODS AND RESULTS

We simultaneously measured left ventricular pressure (LVP) by using a micromanometer-tipped catheter and obtained echocardiograms in 20 patients with severe AS. We estimated LVP curves and calculated pressure-strain loops using three different models: (i) the model validated in patients without AS; (ii) the same model, but with pressure at the aortic valve opening (AVO) adjusted to diastolic cuff pressure; and (iii) a new model based on the invasive measurements from patients with AS. Valvular events were determined by echocardiography. Peak LVP was estimated as the sum of the mean aortic transvalvular gradient and systolic cuff pressure. In same-beat comparisons between invasive and estimated LVP curves, Model 1 significantly overestimated early systolic pressure by 61 ± 5 mmHg at AVO compared with Models 2 and 3. However, the average correlation coefficients between estimated and invasive LVP traces were excellent for all models, and the overestimation had limited influence on MWI, with excellent correlation (r = 0.98, P < 0.001) and good agreement between the MWI calculated with estimated (all models) and invasive LVP.

CONCLUSION

This study confirms the validity of the non-invasive MWI in patients with AS. The accuracy of estimated LVP curves improved when matching AVO to the diastolic pressure in the original model, mirroring that of the AS-specific model. This may sequentially enhance the accuracy of regional MWI assessment.

Global constructive work is associated with ventricular arrhythmias after cardiac resynchronization therapy

AIMS

Non-invasive left ventricular (LV) pressure-strain loops provide a novel method for quantifying myocardial work by incorporating LV pressure in measurements of myocardial deformation. Early studies suggest that myocardial work parameters such as global constructive work (GCW) could be useful and reliable in arrhythmia prediction, particularly in patients undergoing cardiac resynchronization therapy (CRT). The aim of this study was to evaluate whether the magnitude of GCW was associated with the occurrence of ventricular arrhythmias in patients after CRT.

METHODS AND RESULTS

Patients on guideline-recommended treatment with a CRT defibrillator (CRT-D) were evaluated by 2D speckle-tracking echocardiography including measurements of GCW at least 6 months after implantation. The primary outcome was a composite of appropriate defibrillator therapy and sustained ventricular arrhythmia under the monitor zone. A total of 162 patients [mean age 66 years (±10), 122 males (75%)] were included. Sixteen (10%) patients experienced the primary outcome during a median follow-up of 18 months (interquartile range: 12-25) after the performance of index echocardiography. Patients with a below-median GCW (<1473 mmHg%) had a hazard ratio (HR) for the outcome of 8.14 [95% confidence interval (CI): 1.83-36.08], P = 0.006 compared with patients above the median in a univariate model and remained an independent predictor after multivariate adjustment for the estimated glomerular filtration rate and QRS duration [HR 4.75 (95% CI: 1.01-22.28), P < 0.05].

CONCLUSION

In patients treated with CRT-D, a GCW below median level was associated with a five-fold increase in the risk of ventricular arrhythmias.

Non-Invasive Imaging Assessment in Patients with Aortic Coarctation: A Contemporary Review

Coarctation of the aorta (CoA) is a congenital abnormality characterized by a narrowing of the aortic lumen, which can lead to significant morbidity and mortality if left untreated. Even after repair and despite significant advances in therapeutic management, these patients have overall reduced long-term survival due to the consequences of chronic afterload increase. Cardiovascular imaging is key from the first diagnosis to serial follow-up. In recent years, novel imaging techniques have emerged, increasing accessibility to advanced imaging modalities and enabling early and non-invasive identification of complications after repair. The aim of this paper is to provide a comprehensive review of the role of different imaging techniques in the evaluation and management of patients with native or repaired CoA, highlighting their unique strengths and limitations.

Feature-Tracking-Derived Strain Analysis for Identification of Subendocardium-Involved Late Gadolinium Enhancement in Load-Induced Left Ventricular Hypertrophy: A Multicenter Study of Cardiac Magnetic Resonance Data

BACKGROUND

Subendocardium-involved late gadolinium enhancement (SILGE) is a significant predictor of poor prognosis in patients with load-induced left ventricular hypertrophy (LVH).

OBJECTIVES

This multicenter study aimed to investigate whether the diagnostic performance of cardiac magnetic resonance feature-tracking (CMR-FT)-derived strain analysis for detecting subtle subendocardial injury would be influenced by its load dependence in patients with load-induced LVH.

METHODS

A total of 149 patients with load-induced LVH were recruited from three centers and underwent enhanced CMR imaging. The patients were divided into two groups based on the presence or absence of SILGE on CMR (SILGE+ group: n = 56; SILGE- group: n = 93). Clinical and CMR parameters were evaluated in both groups.

RESULTS

The LV systolic pressure (LVSP) and LV end-diastolic pressure (LVEDP) in the SILGE+ group were higher than those in the SILGE- group (each with p < 0.05), and LVSP and LVEDP were correlated with the LV global longitudinal strain (GLS) (each with p < 0.05) in research center 1. The LV strain parameters were significantly lower in the SILGE+ group than those in the SILGE- group (each with p < 0.05). Logistic regression analysis identified GLS (OR 1.325; 95% CI 1.180 to 1.487, p < 0.001) as a predictive factor of SILGE in the patients with load-induced LVH. The receiver operating characteristic (ROC) curve analysis results indicated that the areas under the curve (AUC) of global radial strain (GRS), global circumferential strain (GCS), and GLS were 0.68, 0.69, and 0.76, respectively. De Long's test results implied that GLS had the best diagnostic performance for SILGE (p = 0.04).

CONCLUSION

Despite the load dependency of CMR-FT-derived strain analysis, the GLS exhibits reasonable accuracy in the identification of SILGE and can potentially serve as a feasible alternative for detecting subendocardial involvement in patients with load-induced LVH who are contraindicated for LGE.

Application of myocardial work in predicting adverse events among patients with resistant hypertension

BACKGROUND

Hypertension is the most common chronic disease and the leading risk factor for disability and premature deaths worldwide. Approximately 10-20% of all patients with hypertension and 15-18% of the general population who are treated for hypertension have resistant hypertension (RH). Patients with RH have a higher risk of end-organ damage, such as carotid intima-media thickening, retinopathy, left ventricular hypertrophy and heart failure, myocardial infarction, stroke, impaired renal function, and death than those with controlled blood pressure. In the present study, we applied echocardiography to patients with RH to evaluate myocardial work (MW) and determine whether it is predictive for the occurrence of adverse events within 3 years.

METHODS

We included 283 outpatients and inpatients aged ≥ 18 years who met the clinical criteria for RH, without arrhythmia and severe aortic valve stenosis, between July 2018 and June 2019. The patients were followed up for 3 years from starting enrollment, and any adverse event that occurred during the period was used as the observation end point. Each enrolled patient underwent a complete transthoracic echocardiogram examination, blood pressure was measured and recorded, and MW was then analyzed.

RESULTS

Eighty-two (28.98%) patients with RH had adverse events, such as myocardial infarction (n = 29, 35.36%), heart failure (n = 4, 0.05%), renal insufficiency (n = 40, 48.78%), renal failure (n = 2, 0.02%), cerebral infarction (n = 5, 0.06%), and cerebral hemorrhage (n = 2, 0.02%), and no death events occurred. In patients with RH and adverse events, global longitudinal strain (GLS) (- 16% vs. - 18%), the global work index (2079 mmHg% vs. 2327 mmHg%), global constructive work (2321 mmHg% vs. 2610 mmHg%), and global work efficiency (93% vs. 94%) were lower than those in patients without adverse events. However, global wasted work (GWW) was higher in patients with RH and adverse events than in those without adverse events (161 mmHg% vs. 127 mmHg%). GLS and GWW were the most significant in predicting adverse events.

CONCLUSIONS

MW, especially GLS and GWW, is a good method to predict 3-year adverse events in patients with RH.

Left ventricular strain and myocardial work in short-term peritoneal dialysis patients

BACKGROUND

Initiation of dialysis encompasses new cardiovascular challenges on patients with end-stage renal disease (ESRD). This study used two-dimensional speckle-tracking echocardiography (2D-STE) to investigate the change of left ventricular (LV) myocardial function undergoing peritoneal dialysis (PD) within 1-3 months.

METHODS

A total of 56 patients with ESRD and 27 healthy controls were enrolled in this prospective study. Mean duration of PD was 44.41 ± 16.44 days. We evaluated LV myocardial function of patients with ESRD in baseline and within 1-3 months after PD by 2D-STE with global longitudinal strains (GLS) and myocardial work (MW). Based on the level of serum phosphate before PD, patients were divided into two groups: the group with normal serum phosphate or hyperphosphatemia.

RESULTS

Compared with healthy controls, patients with ESRD had impaired GLS (p < .001) and increased global work index (GWI) (p = .034), global constructive work (GCW) (p < .001), global wasted work (GWW) (p < .001), and lower global work efficiency (GWE) (p = .002). After PD therapy, GWI (p = .001), GCW (p < .001), and GWW (p = .023) decreased and closed to healthy subjects (p > .05) and no significant improvement was observed in GLS (p = .387). GLS of basal segments worsened in the hyperphosphatemia group (p = .005) and GWW reduced remarkably in the group with normal serum phosphate after PD treatment (p = .008). The change of left ventricular internal diameter in diastole (LVIDd) was the only parameter influenced GWI in post-dialysis patients (β = 0.324, p = .013).

CONCLUSIONS

Short-term PD treatment improved LV MW in ESRD patients. They benefited more when receiving treatment before the increase of serum phosphorus.

Multimodality Imaging Assessment of Tetralogy of Fallot: From Diagnosis to Long-Term Follow-Up

Tetralogy of Fallot (TOF) is the most common complex congenital heart disease with long-term survivors, demanding serial monitoring of the possible complications that can be encountered from the diagnosis to long-term follow-up. Cardiovascular imaging is key in the diagnosis and serial assessment of TOF patients, guiding patients' management and providing prognostic information. Thorough knowledge of the pathophysiology and expected sequalae in TOF, as well as the advantages and limitations of different non-invasive imaging modalities that can be used for diagnosis and follow-up, is the key to ensuring optimal management of patients with TOF. The aim of this manuscript is to provide a comprehensive overview of the role of each modality and common protocols used in clinical practice in the assessment of TOF patients.

Effect of maximum exercise on left ventricular deformation and its correlation with cardiopulmonary exercise capacity in competitive athletes

BACKGROUND

Global longitudinal strain (GLS) and global myocardial work index (GWI) allow early detection of subclinical changes in left ventricular (LV) systolic function. The aim of the study was to investigate the immediate effects of maximum physical exercise by different exercise testing methods on early post exercise LV deformation parameters in competitive athletes and to analyze their correlation with cardiopulmonary exercise capacity.

METHODS

To reach maximum physical exercise, cardiopulmonary exercise testing (CPET) was performed by semi-recumbent ergometer in competitive handball players (n = 13) and by treadmill testing in competitive football players (n = 19). Maximum oxygen uptake (VO2max) indexed to body weight (relative VO2max) was measured in all athletes. Transthoracic echocardiography and blood pressure measurements were performed at rest and 5 min after CPET in all athletes. GLS, GWI and their changes before and after CPET (ΔGLS, ΔGWI) were correlated with (relative) VO2max.

RESULTS

In handball and football players, GLS and GWI did not differ significantly before and after CPET. There were no significant correlations between GLS and relative VO2max, but moderate correlations were found between ΔGWI and relative VO2max in handball (r = 0.631; P = 0.021) and football players (r = 0.592; P = 0.008). Furthermore, handball (46.7 ml/min*kg ± 4.7 ml/min*kg vs. 37.4 ml/min*kg ± 4.2; P = 0.004) and football players (58.3 ml/min*kg ± 3.7 ml/min*kg vs. 49.7 ml/min*kg ± 6.8; P = 0.002) with an increased ΔGWI after CPET showed a significant higher relative VO2max.

CONCLUSION

Maximum physical exercise has an immediate effect on LV deformation, irrespective of the used testing method. The correlation of relative VO2max with ΔGWI in the early post exercise period, identifies ΔGWI as an echocardiographic parameter for characterizing the current individual training status of athletes.

Left ventricular myocardial strain responding to chronic pressure overload in patients with resistant hypertension evaluated by feature-tracking CMR

OBJECTIVES

The study aimed to investigate the alterations of myocardial deformation responding to long-standing pressure overload and the effects of focal myocardial fibrosis using feature-tracking cardiac magnetic resonance (FT-CMR) in patients with resistant hypertension (RH).

METHODS

Consecutive RH patients were prospectively recruited and underwent CMR at a single institution. FT-CMR analyses based on cine images were applied to measure left ventricular (LV) peak systolic global longitudinal (GLS), radial (GRS), and circumferential strain (GCS). Functional and morphological CMR variables, and late gadolinium enhancement (LGE) imaging were also obtained.

RESULTS

A total of 50 RH patients (63 ± 12 years, 32 men) and 18 normotensive controls (57 ± 8 years, 12 men) were studied. RH patients had a higher average systolic blood pressure than controls (166 ± 21 mmHg vs. 116 ± 8 mmHg, p < 0.001) with the intake of 5 ± 1 antihypertensive drugs. RH patients showed increased LV mass index (78 ± 15 g/m2 vs. 61 ± 9 g/m2, p < 0.001), decreased GLS (- 16 ± 3% vs. - 19 ± 2%, p = 0.001) and GRS (41 ± 12% vs. 48 ± 8%, p = 0.037), and GCS was reduced by trend (- 17 ± 4% vs. - 19 ± 4%, p = 0.078). Twenty-one (42%) RH patients demonstrated a LV focal myocardial fibrosis (LGE +). LGE + RH patients had higher LV mass index (85 ± 14 g/m2 vs. 73 ± 15 g/m2, p = 0.007) and attenuated GRS (37 ± 12% vs. 44 ± 12%, p = 0.048) compared to LGE - RH patients, whereas GLS (p = 0.146) and GCS (p = 0.961) were similar.

CONCLUSION

Attenuation of LV GLS and GRS, and GCS decline by tendency, might be adaptative changes responding to chronic pressure overload. There is a high incidence of focal myocardial fibrosis in RH patients, which is associated with reduced LV GRS.

CLINICAL RELEVANCE STATEMENT

Feature-tracking CMR-derived myocardial strain offers insights into the influence of long-standing pressure overload and of a myocardial fibrotic process on cardiac deformation in patients with resistant hypertension.

KEY POINTS

• Variations of left ventricular strain are attributable to the degree of myocardial impairment in resistant hypertensive patients. • Focal myocardial fibrosis of the left ventricle is associated with attenuated global radial strain. • Feature-tracking CMR provides additional information on the attenuation of myocardial deformation responding to long-standing high blood pressure.

Myocardial Work in Middle-Aged Adults with Overweight and Obesity: Associations with Sex and Central Arterial Stiffness

We explored global myocardial work index (GWI), a novel measure of myocardial function that integrates left ventricular (LV) hemodynamic load, in relation to sex and increased body mass index (BMI). We used data from 467 individuals (61% women, average age 47 ± 9 years and BMI 31.2 kg/m2) without known cardiac disease. Central arterial function was analysed by applanation tonometry. GWI was calculated from global longitudinal strain (GLS) and post-echocardiography supine blood pressure (BP). Covariables of GWI were identified in linear regression analyses. Women had higher BMI, aortic augmentation pressure (12 ± 7 vs. 8 ± 6 mmHg), LV GLS (20.0 ± 2.8 vs. 18.8 ± 2.8%), and GWI (2126 ± 385 vs. 2047 ± 389 mmHg%) than men (all p < 0.05). In univariable analyses, higher GWI was associated with female sex, higher age, systolic BP, LV wall stress, LV ejection fraction, left atrial size, LV ejection time, and with lower waist circumference (all p < 0.05). In multivariable analysis, adjusting for these correlates, female sex remained independently associated with higher GWI (β = 0.13, p = 0.007). After additional adjustment for aortic augmentation pressure or central pulse pressure, this association became non-significant. In conclusion, the higher GWI in women compared to men was mainly explained by increased LV workload due to higher aortic augmentation pressure in women.

Segmental and global myocardial work in hypertensive patients with different left ventricular ejection fraction: what's the role of the apex played?

We investigated myocardial work in hypertension (HT) among patients with different left ventricular ejection fraction (LVEF) to analyze the contribution of segmental myocardial work to global myocardial work. 114 patients with HT were divided into 4 groups: HTsnEF ("supra-normal" EF, > 65%); HTnEF ("normal" EF, 60-65%); HTmEF (designed as "middle" EF, 50-60%, within an abnormal LV geometry); HTrEF (reduced EF, < 50%). Longitudinal strain (LS) and myocardial work indices were obtained by echocardiography: myocardial work index (MWI), constructive work (MCW), wasted work (MWW), myocardial work efficiency (MWE), and percentages of apical work were calculated (PApi-MWI, PApi-MCW). Global LS (GLS) and global MWE (GWE) decreased in HTmEF and HTrEF groups. Global MWI(GWI) and MCW(GCW) increased in HTsnEF and HTnEF groups, and subsequently decreased, particularly in HTrEF group (P < 0.05). GWW increased in all HT subgroups. All segmental MWI and MCW were elevated or preserved initially in HTsnEF and HTnEF groups, and subsequently decreased, obviously in basal and middle segments in HTrEF group (P < 0.05). All segmental MWW increased and MWE decreased in HTmEF and HTrEF groups (P < 0.05). PApi-MWI and PApi-MCW increased initially, and subsequently decreased in HTmEF group, and elevated significantly in HTrEF group. Correlation analysis revealed a close connection of GLS and myocardial work parameters with LVEF. Apical myocardial work increased at the early stages of hypertensive systolic dysfunction, as a compensatory mechanism. Segmental myocardial work analysis added value to explore the distribution of myocardial impairment.

Ventricular-arterial coupling (VAC) in a population-based cohort of middle-aged individuals: The STANISLAS cohort

BACKGROUND AND AIMS

Data exploring normal values of different ventricular-arterial coupling (VAC) parameters and their association with anthropometric and cardiovascular (CV) factors are scarce. We aim to report values of two different methods of VAC assessment according to age and sex and explore their association with CV factors within a large population-based cohort of middle-aged individuals.

METHODS

For 1333 (mean age 48 ± 14) individuals participating in the 4th visit of the STANISLAS cohort, VAC was assessed by two methods [1]: arterial elastance (Ea)/end-systolic elastance (Ees) and [2] Pulse wave velocity (PWV)/Global longitudinal strain (GLS).

RESULTS

The mean values of Ea/Ees and PWV/GLS were 1.06 ± 0.20 and 0.42 ± 0.12, respectively. The two methods of VAC assessment were poorly correlated (Pearson's correlation coefficient r = 0.14 (0.08; 0.19)). Increased PWV/GLS was associated with older age and a higher degree of cardiovascular risk factors (i.e., BMI, blood pressure, LDL, diabetes, hypertension) in the whole population as well as in the parent generation. In contrast, higher Ea/Ees were associated with decreasing age, and lower prevalence of risk factors in the whole cohort but neutrally associated with risk factors in the parent generation.

CONCLUSIONS

Higher PWV/GLS is significantly associated with CV factors regardless of age. In contrast, worse Ea/Ees is associated with a better CV risk profile when considering individuals aged 30 to 70 but neutrally associated with CV factors when considering only older patients. These results may suggest that PWV/GLS should preferably be used to explore VAC. In addition, age-individualized threshold of Ea/Ees should be used.

The impact of upright posture on left ventricular deformation in athletes

Besides LV ejection fraction (LVEF), global longitudinal strain (GLS) and global myocardial work index (GWI) are increasingly important for the echocardiographic assessment of left ventricular (LV) function in athletes. Since exercise testing is frequently performed on a treadmill, we investigated the impact of upright posture on GLS and GWI. In 50 male athletes (mean age 25.7 ± 7.3 years) transthoracic echocardiography (TTE) and simultaneous blood pressure measurements were performed in upright and left lateral position. LVEF (59.7 ± 5.3% vs. 61.1 ± 5.5%; P = 0.197) was not affected by athletes' position, whereas GLS (- 11.9 ± 2.3% vs. - 18.1 ± 2.1%; P < 0.001) and GWI (1284 ± 283 mmHg% vs. 1882 ± 247 mmHg%; P < 0.001) were lower in upright posture. Longitudinal strain was most frequently reduced in upright posture in the mid-basal inferior, and/or posterolateral segments. Upright posture has a significant impact on LV deformation with lower GLS, GWI and regional LV strain in upright position. These findings need to be considered when performing echocardiography in athletes.

Evolution of non-invasive myocardial work variables after transcatheter aortic valve implantation in patients with severe aortic stenosis

INTRODUCTION

Guidelines recommend aortic valve replacement in patients with severe aortic stenosis who present with symptoms or left ventricular ejection fraction<50%, both conditions representing a late stage of the disease. Whereas global longitudinal strain is load dependent, but interesting for assessing prognosis, myocardial work has emerged.

AIM

To evaluate acute changes in myocardial work occurring in patients undergoing transcatheter aortic valve implantation (TAVI).

METHODS

Patients who underwent TAVI were evaluated before and after by echocardiography. Complete echocardiographies were considered. Myocardial work indices (global work index, global constructive work, global work efficiency, global wasted work) were calculated integrating mean transaortic pressure gradient and brachial cuff systolic pressure.

RESULTS

One hundred and twenty-five patients underwent successful TAVI, with a significant decrease in mean transaortic gradient (from 52.5±16.1 to 12.2±5.0; P<0.0001). There was no significant change in left ventricular ejection fraction after TAVI. Myocardial work data after TAVI showed a significant reduction in global work index (1389±537 vs. 2014±714; P<0.0001), global constructive work (1693±543 vs. 2379±761; P<0.0001) and global work efficiency (85.0±7.06 vs. 87.1±5.98; P=0.0034). The decrease in global work index and global constructive work after TAVI was homogeneous among different subgroups, based on global longitudinal strain, left ventricular ejection fraction and New York Heart Association status before TAVI. We observed a significant association between global work index and global constructive work before TAVI, and global longitudinal strain degradation after TAVI.

CONCLUSIONS

Myocardial work variables show promising potential in best understanding the left ventricular myocardial consequences of aortic stenosis and its correction. Given their ability to discriminate between New York Heart Association status and global longitudinal strain evolution, we can hypothesize about their clinical value.

Prognostic value of left ventricular global constructive work in patients with cardiac amyloidosis

PURPOSE

The aim of the present study was to evaluate the role of ejection fraction (EF), left ventricular (LV) global longitudinal strain (LVGLS) and global constructive work (GCW) as prognostic variables in patients with cardiac amyloidosis (CA).

METHODS

CA patients were retrospectively identified between 2015 and 2021 at a tertiary care hospital. Comprehensive clinical, biochemical, and imaging evaluation including two-dimensional (2D) echocardiography with myocardial work (MW) analysis was performed. A clinical combined endpoint was defined as all-cause mortality and heart failure readmission.

RESULTS

70 patients were followed for 16 (7-37) months and 37 (52.9%) reached the combined endpoint. Patient with versus without clinical events had a significantly lower LVEF (40.71% vs. 48.01%, p = 0.039), LVGLS (-9.26 vs. -11.32, p = 0.034) and GCW (1034.47mmHg% vs. 1424.86mmHg%, p = 0.011). Multivariable analysis showed that LVEF ( odds ratio (OR): 0.904; 95% confidence interval (CI): 0.839-0.973, p = 0.007), LVGLS ( OR: 0.620; 95% CI: 0.415-0.926, p = 0.020) and GCW ( OR: 0.995; 95% CI: 0.990-0.999, p = 0.016) were significant predictors of outcome, but the model including GCW had the best discriminative ability to predict the combined endpoint (C-index = 0.888). A GCW less than 1443mmHg% was able to predict the clinical endpoint with a sensitivity of 94% and a specificity of 64% (Area under the curve (AUC): 0.771 (95% CI: 0.581-0.961; p = 0.005)).

CONCLUSION

In CA patients, GCW may be of additional prognostic value to LVEF and GLS in predicting heart failure hospitalization and all-cause mortality.

Afterload reduction after non-invasive vagus nerve stimulation in acute heart failure

Introduction

While central blood pressure (BP) has been recognized as a major indicator of left ventricular (LV) afterload, the reduction of central pressure decreases LV afterload and may prevent heart failure (HF) decompensation. Non-invasive transcutaneous vagus nerve stimulation (tVNS) was shown to improve cardiac function in HF patients. In this study, the relationship between active tVNS and reduction of central BP was investigated in patients with acute HF (AHF).

Methods

The 22 patients hospitalized for AHF after initial stabilization (median 80 yrs, males 60%) were randomly assigned to active or sham group. For 1 h daily over 5 days, low-level transcutaneous electrical stimulation (LLTS) (20 Hz, 1 mA) was performed after attaching an ear clip to the tragus (active group) or the earlobe (sham control group). Before and after stimulation, central aortic systolic pressure (CASP), brachial systolic BP (SBP), diastolic BP (DBP) as well as heart rate (HR) were noninvasively measured.

Results

No significant differences in baseline characteristics were observed between the active and sham groups. In the active group, CASP, SBP, DBP, and HR each decreased significantly after stimulation (all p < 0.05), whereas in the sham group, CASP, SBP, DBP, and HR each increased significantly after stimulation (all p < 0.05). All the changes in CASP, SBP, DBP and HR before and after stimulation were also significantly different between active and sham groups (all p < 0.01). There were no device-related side effects.

Conclusion

In this study, the left tragus tVNS resulted in an acute afterload reduction in the elderly AHF patients. Non-invasive LLTS may be useful and safe for reducing afterload in AHF.

Clinical trial registration

ClinicalTrials.gov, identifier UMIN000044121.

Left ventricular systolic function in subjects conceived through assisted reproductive technologies

Background

Over the past decades, assisted reproductive technologies (ART) have gained remarkable influence in the treatment of infertility and account for more than 2 % of births in European countries nowadays. Accumulating evidence suggests ART to cause cardiovascular alterations, including left ventricular (LV) dysfunctions, within its offspring. The aim of this study was to assess LV systolic function in subjects conceived through ART in comparison to spontaneously conceived peers.

Methods

For the assessment of LV morphology and LV function, M-Mode echocardiography, pulsed wave Doppler and two-dimensional speckle tracking echocardiography (2DSTE) were applied. LV ejection fraction (EF) and fractional shortening (FS) were assessed in M-Mode and calculated by Teichholz formula. EF was additionally assessed semiautomatically through 2DSTE.

Results

In total, 64 ART subjects and 83 spontaneously conceived controls with no significant differences in age (12.52 ± 5.64 years vs. 13.20 ± 5.95 years, p = 0.486) and sex were included in the analysis. In the ART cohort, significantly lower values were observed for M-Mode assessed EF (63.63 ± 5.17 % vs. 65.35 ± 5.10 %, p = 0.046) and FS (34.26 ± 3.87 % vs. 35.60 ± 3.84 %, p = 0.038). However, after the adjustment for birth weight percentile and gestational age, M-Mode assessed EF and FS displayed no significant differences between both groups. LV morphology and remaining systolic function parameters, such as mitral annular plane systolic excursion, aortic velocity time integral, global peak longitudinal strain and 2DSTE measured EF, were comparable between both groups.

Conclusion

This study suggests a lower LV systolic function in ART subjects, visualized by significantly lower values for M-Mode assessed EF and FS, compared to spontaneously conceived peers. The clinical relevance of these findings has to be investigated as the above-mentioned parameters were in normal reference range. In addition, LV systolic function parameters evaluated by other echocardiographic imaging modalities were comparable between both groups. Therefore, further studies will be required to evaluate the influence of ART on LV systolic function and cardiovascular morbidity in the future.

How myocardial work could be relevant in patients with an aortic valve stenosis?

AIMS

Myocardial work (MW) calculation is an attractive method to assess left ventricular (LV) myocardial function. In case of aortic stenosis (AS), assessment of work indices is challenging because it requires an accurate evaluation of LV-pressure curves. We sought to evaluate the performances of two distinct methods and to provide a quantitative comparison with invasive data.

METHODS AND RESULTS

Model-based and template-based methods were defined and applied for the evaluation of LV-pressures on 67 AS-patient. Global Constructive (GCW), Wasted (GWW), Positive (GPW), Negative (GNW) MW and Global Work Efficiency (GWE), and Index (GWI) parameters were calculated using the available software computing the indices using brachial blood-pressure and trans-aortic mean pressure gradient (MPG) for estimating the LV-pressures vs. using a model-based and homemade software. A complete comparison was performed with invasive measurements. Patients were characterized by MPG of 49.8 ± 14.8 mmHg, the global longitudinal strain (GLS) was -15.0 ± 4.04%, GCW was 2107 ± 800 mmHg.% (model-based) and 2483 ± 1068 mmHg.% (template-based). The root mean square error (RMSE) and correlation were calculated for each patient and pressure estimation methods. The mean RMSE are 33.9 mmHg and 40.4 mmHg and the mean correlation coefficients are 0.81 and 0.72 for the model-based and template-based methods, respectively. The two methods present correlation coefficient r2 >0.75 for all the indices.

CONCLUSION

The two non-invasive methods of LV pressure estimation and work indices computation correlate with invasive measurements. Although the model-based approach requires less information and is associated with slightly better performances, the implementation of template-based method is easier and is appropriate for clinical practice.

The impact of medical therapy on left ventricular strain: Current state and future perspectives

The speckle tracking strain is becoming a frequently used marker of subclinical left ventricular systolic dysfunction. Despite the wide range of data concerning left ventricular strain variability in the general population and its changes in various pathologic conditions, the information about the impact of medical therapy on left ventricle strain is limited. This article provides an analysis of published studies of left ventricle strain changes in response to different agents and combinations of medical therapies used for hypertension and congestive heart failure.

Left Ventricular Global Longitudinal Strain in Patients with Moderate Aortic Stenosis

Moderate aortic stenosis (AS) is associated with an increased risk for adverse events. Although reduced left ventricular (LV) global longitudinal strain (GLS) is associated with worse outcomes in patients with severe AS, its prognostic value in patients with moderate AS is unknown. The aim of this study was to investigate the prognostic implications of LV GLS in patients with moderate AS.

METHODS

LV GLS was evaluated using speckle-tracking echocardiography in patients with moderate AS (aortic valve area 1.0-1.5 cm²) and reported as absolute (i.e., positive) values. Patients were divided into three groups: LV ejection fraction (LVEF) < 50% (group 1), LVEF ≥ 50% but LV GLS < 16% (group 2), and LVEF ≥ 50% and LV GLS ≥ 16% (group 3). The LV GLS value of 16% was based on spline curve analysis. The primary end point was all-cause mortality.

RESULTS

A total of 760 patients (mean age, 71 ± 12 years; 61% men) were analyzed. During a median follow-up period of 50 months (interquartile range, 26-94 months), 257 patients (34%) died. Patients with LVEF < 50% and LVEF ≥ 50% but LV GLS < 16% showed significantly higher mortality rates at 1-, 3-, and 5-year follow-up (82%, 71%, and 58%; and 92%, 77%, and 58%, respectively) compared with those with LVEF ≥ 50% and LV GLS ≥ 16% (96%, 91%, and 85%, respectively; P < .001). Long-term outcomes were not different between patients with LVEF < 50% and those with LVEF ≥ 50% but LV GLS < 16% (P = .592). LV GLS discriminated higher risk patients even among those with LVEF ≥ 60% (P < .001) or those who were asymptomatic (P < .001). On multivariable analysis, LVEF < 50% (hazard ratio, 2.384; 95% CI, 1.614-3.522; P < .001) and LVEF ≥ 50% but LV GLS < 16% (hazard ratio, 2.467; 95% CI, 1.802-3.378; P < .001) were independently associated with all-cause mortality.

CONCLUSIONS

In patients with moderate AS, reduced LV GLS is associated with an increased risk for all-cause mortality, even if LVEF is still preserved.

Impact of Age and Heart Rate on Strain-Derived Myocardial Work in a Population of Healthy Subjects

Background: The influence of age and gender on strain-imaging-derived myocardial work (MW) was recently investigated in healthy subjects. No information is available on the impact of heart rate (HR) on MW. Methods: 177 healthy subjects (47% men, mean age 42 years) underwent an echo-Doppler exam, including quantification of global longitudinal strain (GLS). Cuff blood pressure was used as a surrogate of left ventricular peak pressure to estimate global work index (GWI), global constructive work (GCW), global wasted work (GWW) and global work efficiency (GWE). Statistical analyses were performed according to age and HR tertiles. Results: GWW was higher in the third HR tertile, i.e., ≥74 bpm (74.7 ± 33.6 mmHg %) than in the first HR tertile (<66 bpm) (61.0 ± 32.5 mmHg %) (p < 0.02). In the pooled population, by adjusting for systolic blood pressure, GLS, E/e’ ratio and left atrial volume index, age was independently associated with GCW (β = 0.748) and GWI (β = 0.685) (both p < 0.0001) and HR with GWW (β = 0.212, p = 0.006) and GWE (β = −0.204, p = 0.007). Conclusions: In healthy subjects age shows a mild influence on GCW. HR exerts an independent negative impact on GWW and GWE: the higher HR the greater wasted work and lower myocardial efficiency.

Left ventricular strain predicts subclinical atherosclerosis in nonadvanced nonalcoholic fatty liver disease patients

OBJECTIVES

The association between nonalcoholic fatty liver disease (NAFLD) and carotid atherosclerosis is still controversial. The present study was designed to assess the relationship between left ventricular systolic mechanics, noninvasively assessed by two-dimensional (2D) speckle-tracking echocardiography (STE) and common carotid artery (CCA) intima-media thickness (IMT), in patients with nonadvanced NAFLD.

METHODS

All consecutive NAFLD patients diagnosed with liver stiffness measurement (LSM) <12.5 kPa on transient elastography between September 2021 and December 2021 were prospectively enrolled. All participants underwent blood tests, transient elastography, 2D transthoracic echocardiography (TTE) implemented with 2D-STE analysis of left ventricular (LV) global longitudinal strain (GLS) and finally carotid ultrasonography. Main independent predictors of subclinical atherosclerosis, defined as CCA-IMT >0. 9 mm, were evaluated.

RESULTS

A total of 92 NAFLD patients (54.0 ± 11.1 years, 50% males) were prospectively analyzed. Mean LSM was 6.2 ± 2.4 kPa. FibroScan results revealed that 76.1% of patients had F0-F1, 5.4% F2 and 18.5% F3 liver fibrosis. Despite normal biventricular systolic function on 2D-TTE, LV-GLS was reduced (less negative than -20%) in 64.1% of patients. However, 62.0% of NAFLD patients were found with CCA-IMT >0. 9 mm. Age [odds ratio (OR),1.19; 95% confidence interval (CI), 1.05-1.36], hypertension (OR, 3.73; 95% CI, 1.53-9.11), LSM (OR, 4.83; 95% CI, 2.43-9.59), LV-GLS (OR, 0.49; 95% CI, 0.36-0.68) and statin therapy (OR, 0.10; 95% CI, 0.02-0.60) were independently associated with subclinical atherosclerosis. Age ≥51 years, LSM ≥5.5 kPa and LV-GLS less negative than -20% were the best cutoff values for predicting subclinical atherosclerosis.

CONCLUSIONS

Subclinical myocardial dysfunction and subclinical atherosclerosis are simultaneously present in patients with nonadvanced NAFLD.

Exploration of the Utility of Speckle-Tracking Echocardiography During Mechanical Ventilation and Mechanical Circulatory Support

This narrative review aims to discuss the potential applicability of speckle-tracking echocardiography (STE) in patients under mechanical ventilation (MV) and mechanical circulatory support (MCS). Both its benefits and limitations were considered through critical analyses of the current available evidence.

Strain-based discoordination imaging during exercise in heart failure with reduced ejection fraction: Feasibility and reproducibility

PURPOSE

Various parameters of mechanical dyssynchrony have been proposed to improve patient selection criteria for cardiac resynchronization therapy, but sensitivity and specificity are lacking. However, echocardiographic parameters are consistently investigated at rest, whereas heart failure (HF) symptoms predominately manifest during submaximal exertion. Although strain-based predictors of response are promising, feasibility and reproducibility during exercise has yet to be demonstrated.

METHODS

Speckle-tracking echocardiography was performed in patients with HF at two separate visits. Echocardiography was performed at rest, during various exercise intensity levels, and during recovery from exercise. Systolic rebound stretch of the septum (SRSsept), systolic shortening, and septal discoordination index (SDI) were calculated.

RESULTS

Echocardiography was feasible in about 70-80% of all examinations performed during exercise. Of these acquired views, 84% of the cine-loops were suitable for analysis of strain-based mechanical dyssynchrony. Test-retest variability and intra- and inter-operator reproducibility at 30% and 60% of the ventilatory threshold (VT) were about 2.5%. SDI improved in the majority of patients at 30% and 60% of the VT, with moderate to good agreement between both intensity levels.

CONCLUSION

Although various challenges remain, exercise echocardiography with strain analysis appears to be feasible in the majority of patients with dyssynchronous heart failure. Inter- and intra-observer agreement of SRSsept and SDI up to 60% of the VT were comparable to resting values. During exercise, the extent of SDI was variable, suggesting a heterogeneous response to exercise. Further research is warranted to establish its clinical significance.

Role of strain echocardiography in patients with hypertension

Hypertension is a well-recognized risk factor for the development of cardiovascular disease, and the early detection of cardiac changes from hypertension can allow reversing these. Hypertensive heart diseases (HHD) refer to the complex and diverse change of the cardiac structure and function secondary to hypertension. Although conventional echocardiography is the most common imaging modality in detecting HHD, it cannot detect subtle changes of cardiac structure in subclinical states. Because strain echocardiography is another echocardiographic modality can detect subclinical myocardial dysfunction by measuring intrinsic myocardial deformation, it became more and more popular in clinical and research fields. In this review article, we described the basic concept of strain echocardiography and summarized several clinical studies showing its clinical utilities in the detection of HHD.

Dynamic Handgrip Exercise: Feasibility and Physiologic Stress Response of a Potential Needle-Free Cardiac Magnetic Resonance Stress Test

Background: Cardiac magnetic resonance (CMR) pharmacological stress-testing is a well-established technique for detecting myocardial ischemia. Although stressors and contrast agents seem relatively safe, contraindications and side effects must be considered. Substantial costs are further limiting its applicability. Dynamic handgrip exercise (DHE) may have the potential to address these shortcomings as a physiological stressor. We therefore evaluated the feasibility and physiologic stress response of DHE in relation to pharmacological dobutamine-stimulation within the context of CMR examinations.

Methods: Two groups were prospectively enrolled: (I) volunteers without relevant disease and (II) patients with known CAD referred for stress-testing. A both-handed, metronome-guided DHE was performed over 2 min continuously with 80 contractions/minute by all participants, whereas dobutamine stress-testing was only performed in group (II). Short axis strain by fast-Strain-ENCoded imaging was acquired at rest, immediately after DHE and during dobutamine infusion.

Results: Eighty middle-aged individuals (age 56 ± 17 years, 48 men) were enrolled. DHE triggered significant positive chronotropic (HR_rest: 68 ± 10 bpm, HR_DHE: 91 ± 13 bpm, p < 0.001) and inotropic stress response (GLS_rest: −19.4 ± 1.9%, GLS_DHE: −20.6 ± 2.1%, p < 0.001). Exercise-induced increase of longitudinal strain was present in healthy volunteers and patients with CAD to the same extent, but in general more pronounced in the midventricular and apical layers (p < 0.01). DHE was aborted by a minor portion (7%) due to peripheral fatigue. The inotropic effect of DHE appears to be non-inferior to intermediate dobutamine-stimulation (GLS_DHE= −19.5 ± 2.3%, GLS_Dob= −19.1 ± 3.1%, p = n.s.), whereas its chronotropic effect was superior (HR_DHE= 89 ± 14 bpm, HR_Dob= 78 ± 15 bpm, p < 0.001).

Conclusions: DHE causes positive ino- and chronotropic effects superior to intermediate dobutamine-stimulation, suggesting a relevant increase of myocardial oxygen demand. DHE appears to be safe and timesaving with broad applicability. The data encourages further studies to determine its potential to detect obstructive CAD.

Global Myocardial Work Combined with Treadmill Exercise Stress to Detect Significant Coronary Artery Disease

BACKGROUND

Myocardial work (MW) derived from the left ventricular pressure-strain loop is a novel and noninvasive method for assessing left ventricular function that accounts for loading conditions. We aimed to explore whether global MW combined with treadmill exercise stress could detect significant coronary artery disease (CAD) in patients with angina pectoris.

METHODS

Eighty-five patients with angina pectoris and no prior CAD history were included. All patients underwent treadmill exercise stress echocardiography and coronary angiography. Global MW was constructed from speckle-tracking echocardiography indexed to the brachial systolic blood pressure. The association between MW parameters and the presence of significant CAD was assessed with logistic regression. The discriminative power of MW parameters to detect CAD was assessed with receiver operative characteristic curve, net reclassification improvement, and integrated discrimination improvement analysis.

RESULTS

Twenty-five patients had a positive exercise echocardiogram, while significant coronary artery stenosis (≥70% in one or more major epicardial vessels or ≥50% in the left main coronary artery) was observed in 41 patients. The global wasted work (GWW) and global work efficiency (GWE) were significantly higher or lower, respectively, in patients with significant CAD compared with those of nonsignificant CAD at the peak exercise and during recovery periods (P < .05 for all). Multivariate logistic regression analysis demonstrated that peak GWE and recovery GWW could predict significant CAD. Peak GWE had the highest area under the receiver operating characteristic curve (AUC) among all global MW parameters (AUC = 0.836). Furthermore, a model comprising peak GWE and recovery GWW performed better for the identification of significant CAD than peak GWE alone (AUC = 0.856).

CONCLUSIONS

Peak GWE could detect significant CAD. The new model, incorporating peak GWE and recovery GWW, not only identified but also provided additional value for estimating the probability of significant CAD. Global MW parameters combined with exercise stress perform as an accurate noninvasive screening before the invasive diagnostic technique.

Myocardial Work by Speckle Tracking Echocardiography Accurately Assesses Left Ventricular Function of Coronary Artery Disease Patients

Objective: Myocardial work (MW) is a novel non-invasive method that uses speckle tracking echocardiography (STE) to assess left ventricular (LV) function. MW incorporates the global longitudinal strain and afterload conditions. Here we aimed to use MW to assess the LV function of patients with coronary artery disease (CAD) with or without heart failure (HF). Methods: We enrolled a total of 150 individuals (50 each) with CAD and a normal LV ejection fraction (LVEF), CAD with HF, and healthy controls. Patients were divided into the hypertension (HTN) and normal blood pressure (no HTN) subgroups. MW was determined from the pressure-strain loop using STE. The relationships between MW indices and conventional echocardiographic parameters were evaluated, and the MW indices were compared among groups. Results: Univariate and multivariate analyses showed that MW indices were strongly correlated with LVEF. The global work index (GWI) was increased in the CAD with normal LVEF subgroup with HTN vs. controls (1,922.3 ± 393.1 vs. 1,639.7 ± 204.6 mmHg%, p < 0.05) and decreased in CAD patients with HF (no HTN: 940.9 ± 380.6 vs. 1,639.7 ± 204.6 mmHg%, p < 0.05; HTN: 857.3 ± 369.3 vs. 1,639.7 ± 204.6 mmHg%, p < 0.05). Global waste work was increased in all CAD subgroups vs. controls. Global constructive work had the same tendency as GWI in patients with CAD. Global MW efficiency was decreased in all patients with CAD. Conclusion: MW using STE accurately quantifies LV function in patients with CAD. It offers additional information about LV function with respect to disease progression, particularly in CAD patients with a normal LVEF.

The importance of calibration method in determining the association between central blood pressure with left ventricular and left atrial strain

Afterload is an important determinant of left ventricular (LV) and atrial (LA) function, including myocardial strain. Central blood pressure (CBP) is the major component of cardiac afterload and independently associated with cardiovascular risk. However, the optimal means of calibrating CBP is unclear-standard CBP assessment uses systolic (SBP) and diastolic blood pressure (DBP) from brachial waveforms, but calibration with mean pressure (MAP) and DBP purports to be more accurate. Therefore, we sought to determine which CBP is best associated with LA and LV strain. CBP was measured using both standard and MAP based calibration methods in 546 participants (age 70.7 ± 4.7 years, 45% male) with risk factors for heart failure. Echocardiography was performed in all patients and strain analysis conducted to assess LA/LV function. The associations of CBP with LA and LV strain were assessed using linear regression. MAP-derived CSBP (150 ± 20 mmHg) was higher than standard CSBP (128 ± 15 mmHg) and brachial SBP (140 ± 17 mmHg, p < 0.001), whereas DBPs were similar (84 ± 10, 83 ± 10, and 82 ± 10 mmHg). MAP-derived CSBP was not independently associated with LV strain (p > 0.05), however was independently associated with LA reservoir strain (p < 0.05). Brachial and central DBP were more strongly associated with LA reservoir/conduit and LV strain than brachial and central SBP. LA pump strain was not independently associated with any SBP or DBP parameter (p > 0.05). MAP-derived CBP was more accurate in identifying patients with abnormal LA and LV strain than brachial SBP and standard CBP calibration. In conclusion, CBP calibrated using MAP and DBP may be more accurate in identifying patients with abnormal LA and LV function than standard brachial calibration methods.

Myocardial work and left ventricular contractile reserve during stress echocardiography: An angiographic validation

OBJECTIVE

This study sought to determine the contractile reserve (CR) response to exercise stress echocardiography (ESE) quantified by the novel parameter, non-invasive myocardial work (MW), in subjects with angiographically proven coronary artery disease (CAD).

METHODS

CR was measured by the relative change in ejection fraction (EF), global longitudinal strain (GLS) and MW indices from rest to peak exercise in 304 patients referred for clinically indicated ESE. Positive ESE patients proceeded to coronary angiography and further risk stratified based on either percutaneous or surgical intervention.

RESULTS

CR_GLS and global work index (CR_GWI ) significantly decreased with exercise induced ischemia and angiographically proven significant CAD (CR_GLS -1.6±3.5%; CR_GWI -8.6±511 mm Hg% decrement, p < 0.001) compared to non-ischemic patients (CR_GLS 1.4±2.2%; CR_GWI 398±404 mm Hg% improvement). Global constructive work (CR_GCW ) was significantly higher (p < 0.0001) in non-ischemic (818±457 mm Hg%) and blunted in ischemic patients (208±550 mm Hg%). CR_GCW (AUC .81; 95%CI:.75-.86) demonstrated the most association for inducible ischemia followed by CR_GLS (AUC .75; 95%CI:.69-.80), CR_GWI (AUC .73, 95%CI:.67-.79) and CR_EF (AUC .71; 95%CI:.65-.77, p < 0.001). Subgroup analysis showed patients requiring surgical revascularization demonstrated a significantly lower CR_GWE (-11.5±7.6%, p < 0.05) as a result of reduced CR_GCW (281±573 mm Hg%, p < 0.05) and increased global wasted work (CR_GWW , 289±151 mm Hg%, p = 0.09).

CONCLUSION

Multivessel disease requiring surgical revascularization have the greatest reduction in CR. MW may potentially improve detection of ischemia and further risk stratification during ESE to maximize the benefits of revascularization.

Incremental prognostic value of global myocardial work over ejection fraction and global longitudinal strain in patients with heart failure and reduced ejection fraction

AIMS

Left ventricular (LV) ejection fraction (EF) and global longitudinal strain (GLS) help identify heart failure (HF) patients who are at risk for adverse outcomes. This study aimed to determine whether global myocardial work (GMW), derived from non-invasive LV pressure-strain loops, can provide incremental prognostic information over EF and GLS in patients with HF and reduced EF (HFrEF).

METHODS AND RESULTS

We retrospectively analysed 508 patients (age 62.9 ± 15.8 years, 29.1% female) with LVEF ≤40%. The study endpoint was a composite of all-cause death and HF hospitalization. The incremental value of GMW over clinical and echocardiographic variables including EF and GLS for the association with the composite endpoint was assessed using Cox regression analyses. Over a 1-year follow-up, 183 patients reached the endpoint. Baseline variables associated with the endpoint were age, haemoglobin, LV end-systolic volume, New York Heart Association Class III or IV, E/e' ratio, pulmonary artery systolic pressure, EF, and GLS. Cox regression analysis revealed that GMW [hazard ratio (HR) 1.15, 95% confidence interval (CI) 1.05-1.25, per 100-mmHg% decrease] added incremental prognostic value over these variables. Both EF and GLS were not independent variables when GMW was included in the model. Patients with GMW <750 mmHg% were associated with a significantly higher risk of all-cause death and HF hospitalization (HR 3.33, 95% CI 2.31-4.80) than patients with GMW ≥750 mmHg%.

CONCLUSION

In patients with HFrEF, GMW provides incremental prognostic information over EF and GLS regarding risk of all-cause death and HF hospitalization.

Dynamics of Left Ventricular Myocardial Work in Patients Hospitalized for Acute Heart Failure

BACKGROUND

The left ventricular ejection fraction (LVEF) is the most commonly used measure describing pumping efficiency, but it is heavily dependent on loading conditions and therefore not well-suited to study pathophysiologic changes. The novel concept of echocardiography-derived myocardial work (MyW) overcomes this disadvantage as it is based on LV pressure-strain loops. We tracked the in-hospital changes of indices of MyW in patients admitted for acute heart failure (AHF) in relation to their recompensation status and explored the prognostic utility of MyW indices METHODS AND RESULTS: We studied 126 patients admitted for AHF (mean 73 ± 12 years, 37% female, 40% with a reduced LVEF [<40%]), providing pairs of echocardiograms obtained both on hospital admission and prior to discharge. The following MyW indices were derived: global constructive and wasted work (GCW, GWW), global work index (GWI), and global work efficiency. In patients with HF with reduced ejection fraction with decreasing N-terminal prohormone B-natriuretic peptide levels during hospitalization, the GCW and GWI improved significantly, whereas the GWW remained unchanged. In patients with HF with preserved ejection fraction, the GCW and GWI were unchanged; however, in patients with no decrease or eventual increase in N-terminal prohormone B-natriuretic peptide, we observed an increase in GWW. In all patients with AHF, higher values of GWW were associated with a higher risk of death or rehospitalization within 6 months after discharge (per 10-point increment hazard ratio 1.035, 95% confidence interval 1.005-1.065).

CONCLUSIONS

Our results suggest differential myocardial responses to decompensation and recompensation, depending on the HF phenotype in patients presenting with AHF. The GWW predicted the 6-month prognosis in these patients, regardless of LVEF. Future studies in larger cohorts need to confirm our results and identify determinants of short-term and longer term changes in MyW.

Updated knowledge and practical implementations of stress echocardiography in ischemic and non-ischemic cardiac diseases: an expert consensus of the Working Group of Echocardiography of the Hellenic Society of Cardiology

Stress echocardiography (SE) is a well-established and valid technique, widely-used for the diagnostic evaluation of patients with ischemic and non-ischemic cardiac diseases. This statement of the Echocardiography Working Group of the Hellenic Society of Cardiology summarizes the consensus of the writing group regarding the applications of SE, based on the expertise of their members and on a critical review of current medical literature. The main objectives of the consensus document include a comprehensive review of SE methodology and training, focusing on the preparation, the protocols used and the analysis of the SE images and an updated, evidence-based knowledge about SE applications on ischemic and non-ischemic heart diseases, such as in cardiomyopathies, heart failure and valvular heart disease.

Reduced left ventricular contractility, increased diastolic operant stiffness and high energetic expenditure in patients with severe aortic regurgitation without indication for surgery

OBJECTIVES

Recent mortality studies showed worse prognosis in patients (ARNS) with severe aortic regurgitation and preserved ejection fraction (EF) not fulfilling the criteria of current guidelines for surgery. The aim of our study was to analyse left ventricular (LV) systolic and diastolic function and mechanical energetics to find haemodynamic explanations for the reduced prognosis of these patients and to seek a new concept for surgery.

METHODS

Global longitudinal strain (GLS) and echo-based single-beat pressure-volume analyses were performed in patients with ARNS (LV end-diastolic diameter <70 mm, EF >50%, GLS > -19% n = 41), with indication for surgery (ARS; n = 19) and in mild hypertensive controls (C; n = 20). Additionally, end-systolic elastance (LV contractility), stroke work and total energy (pressure-volume area) were calculated.

RESULTS

ARNS demonstrated significantly depressed LV contractility versus C: end-systolic elastance (1.58 ± 0.7 vs 2.54 ± 0.8 mmHg/ml; P < 0.001), despite identical EF (EF: 59 ± 6% vs 59 ± 7%). Accordingly, GLS was decreased [-15.7 ± 2.7% (n = 31) vs -21.2 ± 2.4%; P < 0.001], end-diastolic volume (236 ± 90 vs 136 ± 30 ml; P < 0.001) and diastolic operant stiffness were markedly enlarged, as were pressure-volume area and stroke work, indicating waste of energy. The correlation of GLS versus end-systolic elastance was good (r = -0.66; P < 0.001). ARNS and ARS patients demonstrated similar haemodynamic disorders, whereas only GLS was worse in ARS.

CONCLUSIONS

ARNS patients almost matched the ARS patients in their haemodynamic and energetic deterioration, thereby explaining poor prognosis reported in literature. GLS has been shown to be a reliable surrogate for LV contractility, possibly overestimating contractility due to exhausted preload reserve in aortic regurgitation patients. GLS may outperform conventional echo parameters to predict more precisely the timing of surgery.

Concept of myocardial fatigue in reversible severe left ventricular systolic dysfunction from afterload mismatch: a case series

Background 

There is already extensive literature on the natural history of hypertensive heart disease (HHD) and aortic stenosis (AS). Once these patients develop severe left ventricular systolic dysfunction (LVSD) despite guideline-directed therapy for heart failure (HF), it is often thought to be end-stage from irreversible adverse remodelling. Our case series challenges this traditional paradigm. A more holistic model that factors in the interactions between the ventricle and vasculature is required. Based on a novel hypothetical concept of myocardial fatigue, we propose that occasionally LVSD is not an inherent myocardial or valvular disease but a consequence of an arterial afterload mismatch. By addressing this, the ventricle may recover and contract efficiently in unison with the arterial system.

Case summary 

We present two cases of severe LVSD in a young lady with long-standing essential hypertension and a gentleman with stable severe AS. Both patients were already established on HF medications. After optimizing their blood pressure control, repeat echocardiography revealed normalization of left ventricular ejection fraction within 3 months, along with a demonstrable improvement in ventricular-arterial coupling and for AS, a reduction in valvular-arterial impedance.

Discussion 

Just as Frank-Starling's law was discovered by initially drawing analogies to skeletal muscle behaviour, it is biologically plausible that cardiac fatigue can occur in the setting of afterload mismatch. The chance of recovery rests upon early recognition before it transitions to irreversible myocardial damage. Only by testing new emerging theories of HF can we galvanize original research and find new avenues to understanding this complex syndrome.

The non-invasive assessment of myocardial work by pressure-strain analysis: clinical applications

Pressure–volume (PV) analysis is the most comprehensive way to describe cardiac function, giving insights into cardiac mechanics and energetics. However, PV analysis still remains a highly invasive and time-consuming method, preventing it from integration into clinical practice. Most of the echocardiographic parameters currently used in the clinical routine to characterize left ventricular (LV) systolic function, such as LV ejection fraction and LV global longitudinal strain, do not take the pressure developed within the LV into account and therefore fall too short in describing LV function as a hydraulic pump. Recently, LV pressure-strain analysis has been introduced as a new technique to assess myocardial work in a non-invasive fashion. This new method showed new insights in comparison to invasive measurements and was validated in different cardiac pathologies, e.g., for the detection of coronary artery disease, cardiac resynchronization therapy (CRT)-response prediction, and different forms of heart failure. Non-invasively assessed myocardial work may play a major role in guiding therapies and estimating prognosis. However, its incremental prognostic validity in comparison to common echocardiographic parameters remains unclear. This review aims to provide an overview of pressure-strain analysis, including its current application in the clinical arena, as well as potential fields of exploitation.

Evaluation of left ventricular myocardial mechanics in patients with normally functioning bicuspid aortic valves: A systematic review and meta-analysis

BACKGROUND

Studies have found conflicting results concerning the left ventricular (LV) myocardial deformation properties in patients with normally functioning bicuspid aortic valves (BAVs). Whether the remodeling process of LV occurs independently in patients with BAV is a matter of debate.

METHOD

We searched PubMed, Embase, Cochrane library, and Web of Science for cohort studies aiming to assess LV function in adults with isolated BAV compared with tricuspid aortic valve (TAV) controls. Standard mean difference (SMD) was calculated from random-effects meta-analyses.

RESULTS

Eight cohort studies were included. There were significantly lower global longitudinal strain (GLS), global radial strain (GRS), global circumferential strain (GCS) in BAV than in TAV controls (GLS: SMD = 0.64, 95% CI: 0.35 to 0.92, P < .0001; GRS: SMD = -0.71, 95% CI: -1.09 to -0.32, P = .0003; GCS: SMD = 0.70, 95% CI: 0.41 to 0.98, P < .00001) and significantly higher left atrial volume index (LAVI) and E/e' in BAV than in TAV controls (LAVI: SMD = 0.50, 95% Cl: 0.12 to 0.88, P = .01; E/e': SMD = 0.54, 95% CI: 0.30 to 0.77, P < .00001). There was significantly higher Left ventricular mass index（LVMI） in BAV than in TAV controls (SMD = 0.51, 95% CI: 0.24 to 0.79, P = .0003). Left ventricular ejection fraction (LVEF) was not significantly different between BAV patients and TAV controls (SMD = 0.05, 95% CI: -0.16 to 0.26, P = .63).

CONCLUSION

The impairment of LV myocardial mechanics, including LV systolic, diastolic dysfunction and LV hypertrophy, is present in patients with normally functioning BAV. This might support the hypothesis that BAV is not only a valvular disease but also a myocardial disease.

Estimated left ventricular pressure-myocardial strain loop as an index of cardiac work predicts all-cause mortality in patients receiving regular hemodialysis

BACKGROUND

A non-invasive method for left ventricular pressure-strain analysis has recently been introduced to provide information on cardiac work and detect subtler changes in cardiac function. This study aims to verify and construct a novel index that could accurately and independently predict the prognosis of patients with end-stage kidney disease (ESRD) receiving regular hemodialysis.

METHODS

Patients with end-stage kidney disease (ESRD) receiving maintenance hemodialysis (4-h sessions, 3 times weekly for 3 months or more) and who underwent echocardiography between 2009 and 2014 in China Medical University Hospital, Taichung, Taiwan, were enrolled. Conventional (left ventricular ejection fraction, LVEF) and strain echocardiography parameters (global longitudinal strain, GLS; cardiac work index, CWI) in 102 eligible patients were analyzed and compared. CWI was calculated from estimated LV pressure-myocardial strain loop area.

RESULTS

Results show that, while no significant differences were found between LVEF (0.57 ± 0.12 vs. 0.59 ± 0.09, P = 0.27) and GLS (-16.12 ± 6.57% vs. -18.44 ± 5.54%, P = 0.07), deceased patients had significantly lower CWI (1339 ± 683.05 mmHg% vs. 1883.38 ± 640.99 mmHg%, P = 0.0002) than surviving patients. The predictive values defined by area under the curve (AUC) of LVEF, GLS and CWI were 0.499, 0.619 and 0.724, respectively.

CONCLUSION

In conclusion, CWI is an accurately independent predictor of all-cause mortality in ESRD patients receiving regular hemodialysis and may superior to the current predictors such as LVEF and GLS.

Resting global myocardial work can improve interpretation of exercise stress echocardiography

Sensitivity and specificity of ESE to determine hemodynamically significant coronary artery disease (CAD) is limited by subjective qualitative interpretation resulting in false-positive results. The objective of this study was to determine whether resting myocardial work estimated from non-invasive left ventricular pressure-strain loops can help improve the interpretation of exercise stress echocardiography (ESE). Resting global myocardial work was performed on 288 patients referred for clinically indicated ESE with no resting regional wall motion abnormalities and normal ejection fraction (≥ 55%). Coronary angiography was used to validate the presence of significant CAD in those with a positive ESE. Resting global myocardial work index (GWI) was significantly reduced (p < 0.001) in patients with true-positive (1544 ± 354 mmHg%) compared to negative (1819 ± 317 mmHg%) and false-positive (1857 ± 344 mmHg%) ESE. A GWI of ≤ 1391 mmHg (AUC 0.73; sensitivity 94%; specificity 73%) predicted true-positive ESE. Predictors of a true-positive ESE were (1) lower myocardial work efficiency (odds ratio 0.731, 95% CI 0.58-0.92, p = 0.007), (2) lower GWI (odds ratio 0.997, 95% CI 0.996-0.999, p = 0.006) (3) male gender (odds ratio 5.47, 95% CI 1.84-16.31, p = 0.002) and (4) E/e' ratio (odds ratio 1.15, CI 1.01-1.31, p = 0.032). Myocardial work is a potentially valuable quantitative parameter that provides incremental value over qualitative ESE interpretation and improves appropriate patient selection for coronary angiography.

Impact of surgical aortic valve replacement on global and regional longitudinal strain across four flow gradient patterns of severe aortic stenosis

To evaluate the impact of surgical aortic valve replacement (SAVR) on global (GLS) and regional longitudinal strain (RLS) across four flow-gradient patterns of severe aortic stenosis (AS) 3 months after surgery. A total of 103 patients with severe AS (aortic valve area < 1.0 cm²) were examined by speckle tracking echocardiography the day before SAVR and at 3-months follow-up. Patients were stratified into four flow-gradient patterns by stroke volume index (>35 mL/m² vs. ≤35 mL/m²) and mean transaortic gradients (>40 mmhg vs. ≤40 mmhg): normal-flow, high gradient (NF/HG); low-flow, high gradient (LF/HG); normal-flow, low gradient (NF/LG); low-flow, low gradient (LF/LG). Strain analysis comprised GLS and RLS at a basal (BLS), mid-ventricular (MLS) and apical level (ALS). Patients with high gradients improved GLS (NF/HG: 16.1 ± 3.5 % vs. 17.3 ± 3.4 %, p = 0.03 and LF/HG: 15.4 ± 3.6 % vs. 16.9 ± 3.1 %, p = 0.03), BLS (NF/HG: 12.7 ± 3.1 % vs. 14.2 ± 3.1 %, p = 0.003 and LF/HG: 11.4 ± 3.2 % vs. 13.8 ± 2.7 %, p = 0.005) and MLS (NF/HG: 15.4 ± 3.3 % vs. 16.5 ± 3.3 %, p = 0.04 and LF/HG: 14.5 ± 3.1 % vs. 16.2 ± 2.7 %, p = 0.01) whereas patients with low gradients showed no improvements three months after SAVR. ALS did not change significantly in any group. Patients with high gradients demonstrated a reduction in left ventricular (LV) mass index (p < 0.001) and N-terminal pro-Brain Natriuretic Peptide levels (p < 0.001) following SAVR in contrast to patients with low gradients. Patients with high gradient severe AS improve GLS and RLS three months after SAVR with concomitant reduction of LV mass and neurohormonal activation whereas patients with low gradients do not improve longitudinal strain, LV mass or neurohormonal activation.

Left ventricular strain for predicting the response to cardiac resynchronization therapy: two methods for one question

AIMS

Myocardial work (manually controlled software) and integral-derived longitudinal strain (automatic quantification of strain curves) are two promising tools to quantify dyssynchrony and potentially select the patients that are most likely to have a reverse remodelling due to cardiac resynchronization therapy (CRT). We sought to test and compare the value of these two methods in the prediction of CRT-response.

MATERIALS AND RESULTS

Two hundred and forty-three patients undergoing CRT-implantation from three European referral centres were considered. The characteristics from the six-segment of the four-chamber view were computed to obtain regional myocardial work and the automatically generated integrals of strain. The characteristics were studied in mono-parametric and multiparametric evaluations to predict CRT-induced 6-month reverse remodelling. For each characteristic, the performance to estimate the CRT response was determined with the receiver operating characteristic (ROC) curve and the difference between the performances was statistically evaluated. The best area under the curve (AUC) when only one characteristic used was obtained for a myocardial work (AUC = 0.73) and the ROC curve was significantly better than the others. The best AUC for the integrals was 0.63, and the ROC curve was not significantly greater than the others. However, with the best combination of works and integrals, the ROC curves were not significantly different and the AUCs were 0.77 and 0.72.

CONCLUSION

Myocardial work used in a mono-parametric estimation of the CRT-response has better performance compared to other methods. However, in a multiparametric application such as what could be done in a machine-learning approach, the two methods provide similar results.