How to measure left ventricular myocardial work by pressure-strain loops

A novel method for the evaluation of right ventricular dysfunction in acute pulmonary embolism: Myocardial work indices

PURPOSE

The presence of right ventricular dysfunction indicates a higher risk status in patients with pulmonary embolism (PE). The RV strain evaluated by speckle-tracking echocardiography seems to be more reliable method in the evaluation of RV dysfunction as compared to standard echocardiographic measures. In this study, we aimed to determine the value of myocardial-work indices in evaluating serial changes of RV function in acute PE.

METHODS

Our study comprised 83 consecutive acute PE patients who admitted to our tertiary cardiovascular hospital. Echocardiography was performed within the first 24-hours of hospitalization, and RV and LV myocardial-work parameters were obtained along with standard echocardiographic parameters. The change in the RV/LVr detected on tomography was selected as the primary outcome measure, and its' predictors were analyzed with classical linear regression and a generalized additive model (GAM).

RESULTS

Among the LV-RV strain and myocardial work parameters, the RV global longitudinal strain (GLS) has borderline statistical significance in predicting the RV/LVr change whereas the RV global work efficiency (RV-GWE) strongly predicted RV/LVr change (p: 0.049 and <0.001, respectively).

CONCLUSION

In this study, classical linear regression and GAM analyses showed that RV-GWE seems to offer a better prediction of RV/LVr change in patients with acute PE.

Myocardial Work Measurement With Functional Capacity Evaluation in Primary Systemic Hypertension Patients: Comparison Between Left Ventricle With and Without Hypertrophy

OBJECTIVE

Noninvasive measurement of myocardial work (MW) incorporates left ventricular (LV) pressure, and, therefore, allows correction of global longitudinal strain for changing afterload conditions. We sought to investigate MW as a tool to detect early signs of LV dysfunction in primary systemic hypertension patients, particularly with different predictive indices.

METHODS AND RESULTS

None left ventricular hypertrophy (NLVH) and left ventricular hypertrophy (LVH) patients established were all primary systemic hypertension with preserved ejection fraction. Forty in NLVH and forty in LVH according to left ventricular end-diastolic mass index (LVEDmassI) were prospectively enrolled. The following indices of MW were assessed: global work index, global constructive work, global wasted work (GWW), and global work efficiency (GWE). Both global work index ( P =0.348) and global constructive work ( P =0.225) were increased in NLVH and decreased in LVH, and GWW ( P <0.001) was increased significantly in NLVH and increased more in LVH, while GWE ( P <0.001) was decreased significantly in NLVH and decreased more in LVH. The clinical utility of GWW (95% CI: 0.802-0.951) and GWE (95% CI: 0.811-0.950) were verified by receiver-operating characteristic curve analysis showing larger net benefits as evaluated with LVH and control comparisons. In multivariate linear regression analysis, 4-dimenaional LVEDmassI was independently associated with GWE ( P =0.018) in systemic hypertension patients. Assessment of intraobserver and interobserver variability in the MW echocardiographic data documented good interclass correlation coefficients (all >0.85).

CONCLUSION

GWW and GWE derived from MW are more accurate, sensitive, and reproducible predictors to detect early LV dysfunction in primary systemic hypertension patients, especially in distinguishing the potential functional abnormality of NLVH and LVH, even though the ejection fraction is preserved.

Feasibility and prognostic significance of ventricular-arterial coupling after myocardial infarction: the RIGID-MI cohort

AIMS

The clinical significance and feasibility of the recently described non-invasive parameters exploring ventricular-arterial coupling (VAC) remain uncertain. This study aimed to assess VAC parameters for prognostic stratification in stable patients with left ventricular ejection fraction (LVEF) ≥40% following myocardial infarction (MI).

METHODS AND RESULTS

Between 2018 and 2021, patients with LVEF ≥40% were evaluated 1 month following MI using transthoracic echocardiography (TTE) and arterial tonometry at rest and after a handgrip test. VAC was studied via the ratio between arterial elastance (Ea) and end-systolic LV elastance (Ees) and between pulse wave velocity (PWV) and global longitudinal strain (GLS). Patients were followed for major adverse cardiovascular events (MACE): all-cause death, acute heart failure, stroke, AMI, and urgent cardiovascular hospitalization. Among the 374 patients included, Ea/Ees and PWV/GLS were obtained at rest for 354 (95%) and 253 patients (68%), respectively. Isometric exercise was workable in 335 patients (85%). During a median follow-up of 32 months (interquartile range: 16-42), 41 (11%) MACE occurred. Patients presenting MACE were significantly older and had a higher prevalence of peripheral arterial disease, lower GLS, higher Ea, PWV, and PWV/GLS ratio. The Ea/Ees ratio and standard TTE parameters during isometric exercise were not associated with MACE. After adjustment, the PWV/GLS ratio was the only VAC parameter independently associated with outcome. Receiver operating characteristic curve analysis identified a PWV/GLS ratio >0.70 (Youden's index = 0.37) as the best threshold to identify patients developing MACE: hazard ratio (95% confidence interval) = 2.2 (1.14-4.27), P = 0.02.

CONCLUSION

The PWV/GLS ratio, assessed 1 month after MI, identifies a group of patients at higher risk of MACE providing additional value on top of conventional non-invasive parameters.

Evaluation the Effect of Anthracyclines on Cardiac Function in Children Lymphoma Survivors by Left Ventricular Myocardial Work

Anthracycline chemotherapy is associated with the left ventricular (LV) dysfunction, but the conventional echocardiographic parameter is insensitive in detecting subclinical cardiac dysfunction, and the role of echocardiography in children cancer survivors (CCSs) has not been well established. Here, the myocardial work (MW) was employed to evaluate the early effect of the anthracyclines on LV function in children lymphoma survivors, as well as to explore the clinical application value of this modality. 51 children lymphoma survivors treated with anthracyclines were included. During the treatments, the echocardiography was performed at baseline (T0 phase), the 3rd (T1 phase) and 6th (T2 phase) chemotherapeutic cycle, respectively. After that, the conventional echocardiographic parameters, LV global longitudinal strain (GLS), and global myocardial work (GMW) parameters were obtained. Finally, these echocardiographic parameters were compared to distinguish the differences among three groups, and correlation analysis was used to identify relationship between GMW parameters and LV GLS. Compared with the baseline, we found that there are no significant differences for LVEF and other conventional echocardiographic parameters after chemotherapy, but the value of LV lateral E/E' increased at T1 and T2 group. The GLS, global work index, global constructed work, and global work efficiency were decreased, while the global wasted work was increased after chemotherapy (all P < 0.05). The correlation analysis showed that the GLS has significant correlation with GMW parameters (all P < 0.001). The MW, as a new noninvasive echocardiography modality, could be used to quantitatively evaluate the LV MW in children lymphoma survivors treated with anthracyclines, which providing a sensitive method to early detect the children's LV dysfunction after the chemotherapy.

Usability of myocardial work parameters to demonstrate subclinical myocardial involvement in normotensive individuals with exaggerated hypertensive response in treadmill exercise testing

Early determination of changes in myocardial functions is essential for the protection of cardiovascular diseases. This study aimed to evaluate myocardial work parameters in healthy individuals who developed an exaggerated hypertensive response during the treadmill exercise test procedure. The study included a total of 64 patients for whom an exercise electrocardiography test was planned for functional capacity evaluation. The study population was divided according to the presence of exaggerated hypertensive response to exercise (EBPRE) (SBP/DBP ≥210/105 mmHg in males ≥190/105 mmHg in females) and normal blood pressure response to exercise (NBPRE). Patients' echocardiographic evaluations were made at rest, and myocardial work parameters were calculated. There was no statistical difference between the groups (NBPRE vs. EBPRE, respectively) in terms of left ventricular 2,3 and 4 chamber strains and global longitudinal strain (GLS) values (-20.6 ± -2.3, -19.7 ± -1.9, p:.13; -21.3 ± -2.7, -21 ± -2.4, p:.68; -21.2 ± -2.2, -21.2 ± -2.3, p:.93; and -20.8 ± -1.5, -20.4 ± -1.5, p:.23, respectively). Global constrictive work (GCW), global waste work (GWW), and global work efficiency (GWE) were not statistically different between the two groups (2374 ± 210, 2465 ± 204, p:.10; 142 ± 64, 127 ± 42, p:.31; 94.3 ± 2.5, 95.1 ± 1.5, p:.18, respectively). In contrast, global work index (GWI) parameters were different between the two groups (2036 ± 149, 2147 ± 150, p < .001). The GWI was independently associated with EBPRE (odds ratio with 95% 3.32 (1.02-11.24), p = .03). The partial effect plots were used for GWI to predict EBPRE, according to the results, an increase in GWI predicts probability of exaggerated hypertensive response. In conclusion, Myocardial work analyses might be used to identify early signs of myocardial involvement in normotensive patients with EBPRE.

Timing and Patient Position During Cuff Blood Pressure Measurement Affect Myocardial Work Parameters Measured by Echocardiography

BACKGROUND

Although cuff blood pressure measurement is a critical parameter to calculate myocardial work noninvasively, there is no recommendation about when and how to measure it. Accordingly, we sought to evaluate the effects of the timing during the echo study and the patient's position on the scanning bed during the cuff blood pressure measurement on myocardial work parameter calculations.

METHODS

One hundred one consecutive patients (44 women, 66 ± 14 years) undergoing clinically indicated echocardiography were prospectively enrolled. During the echocardiographic study, we measured the cuff blood pressure 4 times, using a fully automatic digital blood pressure monitor applied to the right and left arm in the same position throughout the study: BP1, before the start of the echo study, with the patient lying in the supine position; BP2, after positioning the patients on their left side to start the echo study; BP3, at the time of the acquisition of the 3 apical views (4- and 2-chamber and long-axis) used to measured left ventricular global longitudinal strain; and BP4, at the end of the echo study with the patient again in the supine position.

RESULTS

Systolic blood pressureat BP1 was 147 ± 21 mm Hg. Between BP1 and BP2, it dropped by 17 ± 9 mm Hg (P < .05). Systolic blood pressure at BP3 was significantly lower than BP2 (130 ± 20 mm Hg vs 122 ± 18 mm Hg, P < .05), and at BP4 was significantly lower than at BP1 (-9 ± 13 mm Hg, P < .05). The average global longitudinal strain was -16% ± 3%. Accordingly, the global work index was 1,929 ± 441 mm Hg% at BP1, dropped to 1,717 ± 421 at BP2, decreased to 1,602 ± 351 mm Hg% at BP3, and increased to 1,815 ± 386 mm Hg% at BP4 (P < .001).

CONCLUSIONS

The timing during the echocardiography study and the patient's position on the scanning bed are critical determinants of the measured cuff systolic blood pressure and the resulting values of myocardial work parameters.

Evolution and prognostic value of left ventricular deformation and myocardial work parameters in transthyretin amyloid cardiomyopathy

AIMS

Wild-type transthyretin amyloid cardiomyopathy (ATTR-CM) is an increasingly recognized condition. It remains challenging to estimate the extent of disease and the prognosis for most patients. Myocardial work is a sensitive echocardiographic approach that improves the characterization of myocardial damage. We investigate the parameters of myocardial deformation and work in ATTR-CM patients and their changes over time.

METHODS AND RESULTS

We analysed clinical, electrocardiographic, biological, and echocardiographic characteristics in 113 patients [median age 82 (77-85), 90.4% male] diagnosed with wild-type ATTR-CM based on international consensus at a single centre. We compared the data at baseline and 18-month follow-up. Thirty-four patients died and 12 were hospitalized for heart failure at a median follow-up of 935 days (interquartile range 691-1159 days). Left ventricular end-diastolic diameter, left atrial strain during reservoir phase (LASRES), left ventricular longitudinal strain, global work index (GWI), global constructive work significantly decreased from baseline to 18 months, while left ventricular wall thickness increased. Left ventricular ejection fraction, right ventricular free wall strain (FWS), global wasted work (GWW), and global work efficiency did not alter significantly. Strain parameters were identified as prognostic on baseline evaluation using a multivariate analysis: GWI, GWW, FWS, and LASRES. They were significantly associated with the risk of death and hospitalization for heart failure.

CONCLUSION

Multi-chamber strain assessment may improve the surveillance of patients with ATTR-CM, and myocardial work parameters may improve clinical risk stratification in this population.

Myocardial work and left heart deformation parameters across primary mitral regurgitation severity

AIMS

Myocardial work (MW) estimation by pressure-strain loops using speckle tracking echocardiography (STE) has shown to evaluate left ventricular (LV) contraction overcoming the load-dependency limit of LV global longitudinal strain (GLS). This has proved useful in hemodynamic variation settings e.g. heart failure and valvular heart disease. However, the variation of MW and strain parameters across different stages of primary mitral regurgitation (MR) and its impact on symptoms, which was the aim of our study, has never been investigated.

METHODS AND RESULTS

Consecutive patients with mild, moderate and severe MR were prospectively enrolled. Exclusion criteria were: chronic atrial fibrillation, valvular heart prosthesis, previous cardiac surgery. Clinical evaluation, blood sample tests, ECG and echocardiography with STE and MW measurement were performed. Patients were then divided into groups according to MR severity. Differences among the groups and predictors of symptoms (as NYHA class≥2) were explored as study endpoints. Overall, 180 patients were enrolled (60 mild,60 moderate,60 severe MR). LV GLS and global peak atrial longitudinal strain (PALS) reduced according to MR severity. Global constructive work (GCW) and global wasted work (GWW) significantly improved, while global work efficiency (GWE) reduced, in patients with moderate and severe MR. Among echocardiographic parameters, global PALS emerged as the best predictor of NYHA class (p < 0.001;area under curve,AUC = 0.7).

CONCLUSIONS

MW parameters accurately describe the pathophysiology of MR, with initial attempt of LV increased contractility to compensate volume overload parallel to the disease progress, although with low efficacy, while global PALS is the most associated with the burden of MR symptoms.

Global left ventricular myocardial work index and medium-term adverse cardiovascular events after ST-elevation myocardial infarction

BACKGROUND

Left ventricular global longitudinal strain (GLS) has incremental prognostic value over ejection fraction (EF) in patients with ST-segment-elevation myocardial infarction (STEMI), but it is also load dependent. It has been recently demonstrated that Myocardial work (MW), integrating blood pressure with GLS, predicts long-term all-cause mortality. We aimed to further explore the prognostic value of MW for cardiovascular endpoints in patients with STEMI.

METHODS AND RESULTS

Retrospective study of 200 consecutive patients admitted with a STEMI, mean age of 62 (SD 12) years, 79.5% males, that survived to discharge. Transthoracic echocardiography was performed before discharge (5 ± 3 days after admission). Mean follow-up was 790 days. The primary outcome was a composite of cardiovascular death, non-fatal myocardial infarction, and unplanned cardiovascular admission (ACE). During follow-up, 26 patients had a ACE. In univariable Cox regression analysis, male gender, body mass index, GRACE risk score and Global Work Index (GWI) were selected to the multivariable analysis, in which, only GWI (per 100 mmHg% decrease: hazard ratio estimate 1.19, 95% confidence interval 1.07-1.34, p-value = 0.002) remained independently associated with ACE, with effective reclassification of non-events. The best GWI cut-off to predict ACE was ≤1165 mmHg% (Log-rank, p = 0.034).

CONCLUSIONS

LV GWI is independently associated with medium-term ACE. Nevertheless, prospective studies in a larger sample of patients are warranted to confirm this finding.

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 cross-sectional study of factors influencing left ventricular myocardial work in peritoneal dialysis patients

Objectives

To evaluate myocardial work in peritoneal dialysis patients by pressure-strain loop. To analyze the factors influencing myocardial work in peritoneal dialysis patients with preserved ejection fraction.

Methods

We collected clinical data on possible effects on myocardial work in 105 maintenance peritoneal dialysis patients with preserved ejection fraction and applied ultrasonic pressure-strain loops to obtain the left ventricular global constructive work (GCW), Global work index (GWI), global work waste (GWW), and global work efficiency (GWE) of the patients. Then, the clinical data and myocardial work indices were statistically described and correlated.

Results

Left ventricular hypertrophy was observed in 78 % of peritoneal dialysis patients with left ventricular ejection fraction preservation. There is a correlation between the left ventricular mass index and myocardial work indices (P < 0.05). On multiple linear regression analysis, systolic blood pressure (SBP), IL-6, and hemoglobin correlated with GCW(P < 0.05); SBP and IL-6 correlated with GWI(P < 0.05); homocysteine, SBP, TNF-α, and hemoglobin correlated with GWW(P < 0.05); homocysteine, TNF-α and hemoglobin correlated with GWE (P < 0.05).

Conclusions

Using noninvasive pressure-strain loops to assess left ventricular myocardial work can provide information on cardiac function more consistent with pathophysiological changes than conventional ejection fraction. Hypertension, anemia, hyperhomocysteinemia, and inflammation influence left ventricular myocardial work in peritoneal dialysis patients, and they selectively affect one or more myocardial work indices.

Echocardiographic Myocardial Work: A Novel Method to Assess Left Ventricular Function in Patients with Coronary Artery Disease and Diabetes Mellitus

Myocardial ischemia caused by coronary artery disease (CAD) and the presence of metabolic abnormalities and microvascular impairments detected in patients with diabetes mellitus (DM) are a common cause of left ventricular (LV) dysfunction. Transthoracic echocardiography is the most-used, non-invasive imaging method for the assessment of myocardial contractility. The accurate evaluation of LV function is crucial for identifying patients who are at high risk or may have worse outcomes. Myocardial work (MW) is emerging as an alternative tool for the evaluation of LV systolic function, providing additional information on cardiac performance when compared to conventional parameters such as left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS) because it incorporates deformation and load into its analysis. The potential of MW in various conditions is promising and it has gained increased attention. However, larger studies are necessary to further investigate its role and application before giving an answer to the question of whether it can have widespread implementation into clinical practice. The aim of this review is to summarize the actual knowledge of MW for the analysis of LV dysfunction caused by myocardial ischemia and hyperglycemia.

Coronary Microvascular Dysfunction in Patients With Heart Failure: Characterization of Patterns in HFrEF Versus HFpEF

BACKGROUND

Coronary microvascular dysfunction (CMD) is involved in heart failure (HF) onset and progression, independently of HF phenotype and obstructive coronary artery disease. Invasive assessment of CMD might provide insights into phenotyping and prognosis of patients with HF. We aimed to assess absolute coronary flow, absolute microvascular resistance, myocardial perfusion, coronary flow reserve, and microvascular resistance reserve in patients with HF with preserved ejection fraction and HF with reduced ejection fraction (HFrEF).

METHODS

Single-center, prospective study of 56 consecutive patients with de novo HF with nonobstructive coronary artery disease divided into HF with preserved ejection fraction (n=21) and HFrEF (n=35). CMD was invasively assessed by continuous intracoronary thermodilution and defined as coronary flow reserve <2.5. Left ventricular and left anterior descending artery-related myocardial mass was quantified by echocardiography and coronary computed tomography angiography. Myocardial perfusion (mL/min per g) was calculated as the ratio between absolute coronary flow and left anterior descending artery-related mass.

RESULTS

Patients with HFrEF showed a higher left ventricular and left anterior descending artery-related myocardial mass compared with HF with preserved ejection fraction (P<0.010). Overall, 52% of the study population had CMD, with a similar prevalence between the 2 groups. In HFrEF, CMD was characterized by lower absolute microvascular resistance and higher absolute coronary flow at rest (functional CMD; P=0.002). CMD was an independent predictor of a lower rate of left ventricular reverse remodeling at follow-up. In patients with HF with preserved ejection fraction, CMD was mainly due to higher absolute microvascular resistance and lower absolute coronary flow during hyperemia (structural CMD; P≤0.030).

CONCLUSIONS

Continuous intracoronary thermodilution allows the definition and characterization of patterns with distinct CMD in patients with HF and could identify patients with HFrEF with a higher rate of left ventricular reverse remodeling at follow-up.

Right ventricular myocardial work for the prediction of early right heart failure and long-term mortality after left ventricular assist device implant

AIMS

Right heart failure (RHF) after left ventricular assist device (LVAD) implant is burdened by high morbidity and mortality rates and should be prevented by appropriate patient selection. Adequate right ventricular function is of paramount importance but its assessment is complex and cannot disregard afterload. Myocardial work (MW) is a non-invasive Speckle Tracking Echocardiography-derived method to estimate pressure-volume loops. The aim of this study was to evaluate the performance of right ventricular myocardial work to predict RHF and long-term mortality after LVAD implant.

METHODS AND RESULTS

Consecutive patients from May 2017 to February 2022 undergoing LVAD implant were retrospectively reviewed. Patients without a useful echocardiographic exam prior to LVAD implant were excluded. MW analysis was performed. The primary endpoints were early RHF (<30 days from LVAD implant) and death at latest available follow-up. We included 23 patients (mean age 64 ± 8 years, 91% men). Median follow-up was 339 days (IQR: 30-1143). Early RHF occurred in six patients (26%). A lower right ventricular global work efficiency [RVGWE, OR 0.86, 95% confidence intervals (CI) 0.76-0.97, P = 0.014] was associated with the occurrence of early RHF. Among MW indices, the performance for early RHF prediction was greatest for RVGWE [area under the curve (AUC) 0.92] and a cut-off of 77% had a 100% sensitivity and 82% specificity. At long-term follow-up, death occurred in 4 of 14 patients (28.6%) in the RVGWE > 77% group and in 6 of 9 patients (66.7%) in the RVGWE < 77% group (HR 0.25, 95% CI 0.07-0.90, P = 0.033).

CONCLUSION

RVGWE was a predictor of early RHF after LVAD implant and brought prognostic value in terms of long-term mortality.

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.

Myocardial Work Assessment in Patients after Coronary Artery Bypass Grafting during Cardiac Rehabilitation

BACKGROUND

Myocardial work is an innovative echocardiographic tool to assess left ventricular performance. Emerging data have shown the added value of this method for evaluating cardiac function compared to traditional echocardiographic parameters and global longitudinal strain. However, few studies are present in the literature about the role of myocardial work during cardiac rehabilitation. Our aim was to assess the impact of a rehabilitation program on myocardial work indices in patients with preserved left ventricular ejection fraction and after coronary artery bypass grafting. In addition, we assessed the correlation between baseline myocardial work indices and their change after cardiac rehabilitation, establishing an optimal cut-off value to predict the improvement.

METHODS

An observational, single-center, and prospective study was conducted. We enrolled patients referred to cardiac rehabilitation after coronary artery bypass grafting and with preserved left ventricular ejection fraction. Before and after the cardiac rehabilitation program, a comprehensive patient assessment was performed, including traditional transthoracic echocardiography, myocardial work analysis, and a six-minute walk test.

RESULTS

Eighty-four patients were enrolled; the mean age was 67.96 (±7.42) years and 78.6% were male. The left ventricular ejection fraction was preserved in all patients, and the global longitudinal strain was -16.18 ± 2.55%, the global work index was 1588.56 ± 345 mmHg%, the global constructive work was 1771.27 ± 366.36 mmHg%, the global wasted work was 105.8 ± 72.02 mmHg%, and the global work efficiency was 92.63 ± 3.9% at baseline. After the cardiac rehabilitation program, the global work index, the global constructive work, and the six-minute walk test improved significantly (1588.56 ± 345 vs. 1960.2 ± 377.03 mmHg%, p-value < 0.001; 1771.27 ± 366.36 vs. 2172.01 ± 418.73 mmHg%, p-value < 0.001; 70.71 ± 40.2 vs. 437.5 ± 108.70 m, p-value < 0.001, respectively).

CONCLUSIONS

Myocardial work indices, specifically global work index and global constructive work, improve after cardiac rehabilitation program in patients undergoing coronary artery bypass grafting with preserved left ventricular ejection fraction.

Reduced myocardial work in asymptomatic heavy alcohol use and its correlation with epicardial adipose tissue volume and serum biomarkers

BACKGROUND

It is unclear whether long-term heavy alcohol use leads to early cardiac function decline.

HYPOTHESIS

Long-term heavy alcohol use developed reduced cardiac function in subclinical status by analyzing myocardial work (MW). Epicardial adipose tissue (EAT) volume and serum biomarkers contribute to identify potential factors sensitive in predicting early cardiac function decline.

METHODS

We enrolled 31 asymptomatic participants with heavy alcohol use and 33 age and sex-matching nondrinking individuals. Participants underwent echocardiography, MW analysis, EAT volume measurement, serum biochemical examinations, and body composition assessment. We used multivariate linear regression to identify correlation between MW and total cholesterol (TC), EAT volume, and placental growth factor (PlGF). To determine global work efficiency (GWE) below the normal reference value of 96%, we developed receiver operating curves with area under curve (AUC) to compare different combinations of TC, EAT volume, and PlGF.

RESULTS

All 64 participants were male. GWE was reduced in the alcohol use group compared with the control group (96, interquartile range [IQR] = [95-97.75] vs. 97, IQR = [97-98], p = .004). TC was positively associated with GWE (β = .434, 95% confidence interval [CI] = 0.228 to 1.328, p = .008), whereas EAT volume (β = -.398, 95% CI = -0.000446 to -0.000093, p = .005) and PlGF (β = -.493, 95% CI = -1.010 to -0.230, p = .004) were inversely associated with GWE. The most significant AUC for reduced GWE was TC + EAT volume (0.851, 95% CI = 0.671 to 1, p = .006).

CONCLUSION

Asymptomatic heavy alcohol use has shown early reduced cardiac function which can be associated with altered fat metabolism, suggesting individuals with alcohol use and abnormal fat metabolism need to be alert to heart damage.

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.

Antagonism of contractile forces in left ventricular hypertrophy: a diagnostic challenge for better pathophysiological and clinical understanding

Cardiac function is characterised by haemodynamic parameters in the clinical scenario. Due to recent development in imaging techniques, the clinicians focus on the quantitative assessment of left ventricular size, shape and motion patterns mostly analysed by echocardiography and cardiac magnetic resonance. Because of the physiologically known antagonistic structure and function of the heart muscle, the effective performance of the heart remains hidden behind haemodynamic parameters. In fact, a smaller component of oblique transmural netting of cardiac muscle fibres simultaneously engenders contracting and dilating force vectors, while the predominant mass of the tangentially aligned fibres only acts in one direction. In case of hypertrophy, an increased influence of the dilating transmural fibre component might counteract systolic wall thickening, thereby counteract cardiac output. A further important aspect is the response to inotropic stimulation that is different for the tangentially aligned fibre component in comparison to the transmural component. Both aspects highlight the importance to integrate the analysis of intramural fibre architecture into the clinical cardiac diagnostics.

State-of-the-Art: Noninvasive Assessment of Left Ventricular Function Through Myocardial Work

The assessment of myocardial work (MW) using noninvasive pressure-strain loop analysis is a novel echocardiographic method that provides a more precise assessment of cardiac performance by considering the left ventricular loading condition. By integrating various MW components such as index, efficiency, and constructive and wasted work, an extensive analysis of left ventricular mechanics and energetics can be achieved. This approach offers a more comprehensive assessment of global cardiac function and performance, surpassing conventional surrogate indices. In this review, we aim to summarize the existing knowledge on MW and its distinctive characteristics in various cardiac pathologies.

Phenotyping heart failure by echocardiography: imaging of ventricular function and haemodynamics at rest and exercise

Traditionally, congestive heart failure (HF) was phenotyped by echocardiography or other imaging techniques according to left ventricular (LV) ejection fraction (LVEF). The more recent echocardiographic modality speckle tracking strain is complementary to LVEF, as it is more sensitive to diagnose mild systolic dysfunction. Furthermore, when LV systolic dysfunction is associated with a small, hypertrophic ventricle, EF is often normal or supernormal, whereas LV global longitudinal strain can reveal reduced contractility. In addition, segmental strain patterns may be used to identify specific cardiomyopathies, which in some cases can be treated with patient-specific medicine. In HF with preserved EF (HFpEF), a diagnostic hallmark is elevated LV filling pressure, which can be diagnosed with good accuracy by applying a set of echocardiographic parameters. Patients with HFpEF often have normal filling pressure at rest, and a non-invasive or invasive diastolic stress test may be used to identify abnormal elevation of filling pressure during exercise. The novel parameter LV work index, which incorporates afterload, is a promising tool for quantification of LV contractile function and efficiency. Another novel modality is shear wave imaging for diagnosing stiff ventricles, but clinical utility remains to be determined. In conclusion, echocardiographic imaging of cardiac function should include LV strain as a supplementary method to LVEF. Echocardiographic parameters can identify elevated LV filling pressure with good accuracy and may be applied in the diagnostic workup of patients suspected of HFpEF.

Assessment of left ventricular function in patients with type 2 diabetes mellitus by non-invasive myocardial work

Background

Diabetes mellitus (DM) is a chronic disease that poses a serious risk of cardiovascular diseases. Therefore, early detection of impaired cardiac function with non-invasive myocardial imaging is critical for improving the prognosis of patients with DM.

Purpose

This study aimed to assess the left ventricular (LV) function in patients with type 2 diabetes mellitus (T2DM) by non-invasive myocardial work technique.

Materials and methods

In all, 67 patients with T2DM and 28 healthy controls were included and divided into a DM group and a control group. Two-dimensional dynamic images of apical three-chamber view, apical two-chamber view, and apical four-chamber view were collected from all subjects, consisting of at least three cardiac cycles. LV myocardial strain parameters, including global longitudinal strain (GLS) and peak strain dispersion (PSD), as well as myocardial work parameters, including global constructive work (GCW), global wasted work (GWW), global work index (GWI), and global work efficiency (GWE), were obtained and analyzed.

Results

A total of 15 subjects were randomly selected to assess intra-observer and inter-observer consistency of myocardial work parameters and strain parameters, which showed excellent results (intra-class correlation coefficients: 0.856 - 0.983, P<0.001). Compared with the control group, the DM group showed significantly higher PSD (37.59 ± 17.18 ms vs. 27.72 ± 13.52 ms, P<0.05) and GWW (63.98 ± 43.63 mmHg% vs. 39.28 ± 25.67 mmHg%, P<0.05), and lower GWE (96.38 ± 2.02% vs. 97.72 ± 0.98%, P<0.001). Furthermore, the PSD was positively correlated with GWW (r = 0.565, P<0.001) and negatively correlated with GWE (r = -0.569, P<0.001).

Conclusion

Uncoordinated LV myocardial strain, higher GWW, and lower GWE in patients with T2DM may serve as indicators for the early assessment of cardiac impairment in T2DM.

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.

Strain Imaging and Ventricular Arrhythmia

Ventricular arrhythmia is one of the main causes of sudden cardiac death. Hence, identifying patients at risk of ventricular arrhythmias and sudden cardiac death is important but can be challenging. The indication for an implantable cardioverter defibrillator as a primary preventive strategy relies on the left ventricular ejection fraction as a measure of systolic function. However, ejection fraction is flawed by technical constraints and is an indirect measure of systolic function. There has, therefore, been an incentive to identify other markers to optimize the risk prediction of malignant arrhythmias to select proper candidates who could benefit from an implantable cardioverter defibrillator. Speckle-tracking echocardiography allows for a detailed assessment of cardiac mechanics, and strain imaging has repeatedly been shown to be a sensitive technique to identify systolic dysfunction unrecognized by ejection fraction. Several strain measures, including global longitudinal strain, regional strain, and mechanical dispersion, have consequently been proposed as potential markers of ventricular arrhythmias. In this review, we will provide an overview of the potential use of different strain measures in the context of ventricular arrhythmias.

Machine learning-enhanced echocardiography for screening coronary artery disease

BACKGROUND

Since myocardial work (MW) and left atrial strain are valuable for screening coronary artery disease (CAD), this study aimed to develop a novel CAD screening approach based on machine learning-enhanced echocardiography.

METHODS

This prospective study used data from patients undergoing coronary angiography, in which the novel echocardiography features were extracted by a machine learning algorithm. A total of 818 patients were enrolled and randomly divided into training (80%) and testing (20%) groups. An additional 115 patients were also enrolled in the validation group.

RESULTS

The superior diagnosis model of CAD was optimized using 59 echocardiographic features in a gradient-boosting classifier. This model showed that the value of the receiver operating characteristic area under the curve (AUC) was 0.852 in the test group and 0.834 in the validation group, with high sensitivity (0.952) and low specificity (0.691), suggesting that this model is very sensitive for detecting CAD, but its low specificity may increase the high false-positive rate. We also determined that the false-positive cases were more susceptible to suffering cardiac events than the true-negative cases.

CONCLUSIONS

Machine learning-enhanced echocardiography can improve CAD detection based on the MW and left atrial strain features. Our developed model is valuable for estimating the pre-test probability of CAD and screening CAD patients in clinical practice.

TRIAL REGISTRATION

Registered as NCT03905200 at ClinicalTrials.gov. Registered on 5 April 2019.

Serial Non-Invasive Myocardial Work Measurements for Patient Risk Stratification and Early Detection of Cancer Therapeutics-Related Cardiac Dysfunction in Breast Cancer Patients: A Single-Centre Observational Study

Serial transthoracic echocardiographic (TTE) assessment of LVEF and GLS are the gold standard in screening Cancer Therapeutics-Related Cardiac Dysfunction (CTRCD). Non-invasive left-ventricle (LV) pressure-strain loop (PSL) emerged as a novel method to quantify Myocardial Work (MW). This study aims to describe the temporal changes and longitudinal trajectories of MW indices during cardiotoxic treatment. We included 50 breast cancer patients with normal LV function referred for anthracycline therapy w/wo Trastuzumab. Medical therapy, clinical and echocardiographic data were recorded before and 3, 6, and 12 months after initiation of the chemotherapy. MW indices were calculated through PSL analysis. According to ESC guidelines, mild and moderated CTRCD was detected in 10 and 9 patients, respectively (20% CTRCD_mild, 18% CTRCD_mod), while 31 patients remained free of CTRCD (62% CTRCD_neg). Prior to chemotherapy MWI, MWE and CW were significantly lower in CTRCD_mod than in CTRCD_neg and CTRCD_mild. Overt cardiac dysfunction in CTRCD_mod at 6 months was accompanied by significant worse values in MWI, MWE and WW compared to CTRCD_neg and CTRCD_mild. MW features such as low baseline CW, especially when associated with a rise in WW at follow-up, may identify patients at risk for CTRCD. Additional studies are needed to explore the role of MW in CRTCD.

Impact of echocardiographic analyses of valvular event timing on myocardial work indices

AIMS

Valvular event timing is an integral part of echocardiographic pressure-strain loop (PSL) analyses. The impact that different event timing modalities may have on myocardial work indices is unknown.

METHODS AND RESULTS

A methodological study was performed on 200 subjects, including 50 healthy subjects, 50 with aortic valve sclerosis, 50 with atrial fibrillation, and 50 with reduced left ventricular ejection fraction. Valvular event timing was estimated by visual assessment, spectral Doppler, and colour tissue Doppler imaging (TDI) M-mode. These valvular event timings were added to the same PSL analyses sequentially to acquire myocardial work indices, including global work index (GWI). For the 200 participants, the median age was 72 years, 50% were men, and mean blood pressure was 143/80 mmHg. Valvular event timings differed between all three modalities and so did all myocardial work indices. Compared with visual assessment, spectral Doppler resulted in a significantly higher GWI (mean difference: 114 ± 93 mmHg%, P < 0.001), and so did TDI (mean difference: 83 ± 90 mmHg%, P < 0.001). A higher GWI by spectral Doppler than by TDI was also observed (mean difference: 30 ± 53 mmHg%, P < 0.001). In the healthy subgroup, a systematic bias was observed for spectral Doppler compared with visual assessment (mean difference: 160 ± 77 mmHg%, P < 0.001), and a similar trend was noted for TDI vs. visual assessment (mean difference: 124 ± 74 mmHg%, P < 0.001).

CONCLUSION

Myocardial work indices differ depending on the event timing modality used, with visual assessment yielding lower GWI values compared with Doppler-based methods. Serial PSL analyses should apply the same event timing method.

Left bundle branch pacing on mechanical synchrony and myocardial work in bradycardia patients

Left bundle branch pacing (LBBP) has emerged as a novel physiological pacing method to produce narrower QRS duration, but whether it could restore mechanical synchrony and improve myocardial work still lacks sufficient evidence. Therefore, the goal of this study was to evaluate mechanical synchrony and myocardial work in LBBP. We collected 20 patients with LBBP due to symptomatic bradycardia and another 29 age-matched patients with right ventricular pacing (RVP). For LBBP patients, cardiac electro-mechanical synchrony and myocardial work were measured at baseline and 7 days after implantation and compared with the RVP patients. In the LBBP group, paced QRS duration and mechanical synchrony were not significantly different from baseline(all P > 0.05), but significantly smaller than that in the RVP group (all P<0.05). Meanwhile, global longitudinal strain (GLS) in LBBP was greater than that in the RVP group (17.7 ± 3.5% vs. 14.8 ± 3.1%, P < 0.05). Global myocardial work index and global constructive work were also better than that in the RVP group(all P<0.05). Global work efficiency was 91.9 ± 3.1%, which was greater when compared with RVP (P < 0.05). LBBP provides better cardiac electro-mechanical synchrony and more effective myocardial work than that in RVP, thus improving global heart function.

Intraoperative Noninvasive Left Ventricular Myocardial Work Indices in Patients Undergoing On-Pump Coronary Artery Bypass Surgery

OBJECTIVES

Noninvasive echocardiographic analysis of left ventricular (LV) myocardial work (MW) enables insights into cardiac mechanics, contractility, and efficacy beyond ejection fraction (EF) and global longitudinal strain (GLS). However, there are limited perioperative data on patients undergoing coronary artery bypass graft (CABG) surgery. The authors aimed to describe the feasibility and the intraoperative course of this novel assessment tool of ventricular function in these patients, and compare it to conventional 2-dimensional (2D) and 3-dimensional (3D) echocardiographic parameters and strain analysis.

DESIGN

A prospective observational study.

SETTING

At a single university hospital.

PARTICIPANTS

Twenty-five patients with preoperative preserved LV and right ventricular function, sinus rhythm, without significant heart valve disease or pulmonary hypertension, and an uncomplicated intraoperative course scheduled for isolated on-pump CABG surgery.

INTERVENTIONS

Transesophageal echocardiography (TEE) was performed intraoperatively after the induction of anesthesia (T1), after termination of cardiopulmonary bypass (T2), and after sternal closure (T3). All measurements were performed under stable hemodynamic conditions, in sinus rhythm or atrial pacing, and vasopressor support with norepinephrine ≤ 0.1 µg/kg/min.

MEASUREMENTS AND MAIN RESULTS

The EchoPAC v204 software (GE Vingmed Ultrasound AS, Norway) was used for analysis of 2D and 3D LVEF, LV GLS, LV global work index (GWI), LV global constructive work (GCW), LV global wasted work (GWW), and LV global work efficiency (GWE). The MW analysis was feasible in all patients. Although there was no significant difference in the values of 2D and 3D EF during the intraoperative interval, GLS deteriorated significantly after CABG compared to assessment after induction of anesthesia (T1 v T2, -13.3 ± 3.0% v -11.6 ± 3.1%; p = 0.012). The GWI declined significantly after surgery (T1 v T2, 1,224 ± 312 mmHg% v 940 ± 267 mmHg%; p < 0.001), as well as GCW (T1 v T2, 1,460 ± 312 mmHg% v 1,244 ± 336 mmHg%; p = 0.005). The GWW increased after CABG (T1 v T2, 143 mmHg% (IQR 99-183) v 251 mmHg% (IQR 179-361); p < 0.001), and GWE decreased (T1 v T2, 89% (IQR 85-92) v 80% (IQR 75-87); p < 0.001). There were no significant changes in the values of 2D and 3D EF, GLS, GWI, GCW, GWW, and GWE before and after sternal closure (T2 v T3).

CONCLUSION

The intraoperative analysis of noninvasive echocardiographically-assessed LV MW indices is feasible. In the short-term period after uncomplicated on-pump CABG, GLS, as well as global and constructive MW, decreased, whereas wasted work increased, resulting in a less efficient left ventricle. None of these aspects was detected by conventional echocardiographic parameters. Therefore, strain and MW analysis might be more sensitive parameters in detecting myocardial dysfunction by TEE in the perioperative setting, adding information on perioperative cardiac energetics.

The year 2021 in the European Heart Journal—Cardiovascular Imaging: Part I

The European Heart Journal—Cardiovascular Imaging was introduced in 2012 and has during these 10 years become one of the leading multimodality cardiovascular imaging journals. The journal is currently ranked as Number 19 among all cardiovascular journals. It has an impressive impact factor of 9.130 and our journal is well established as one of the top cardiovascular journals. The most important studies published in our Journal in 2021 will be highlighted in two reports. Part I of the review will focus on studies about myocardial function and risk prediction, myocardial ischaemia, and emerging techniques in cardiovascular imaging, while Part II will focus on valvular heart disease, heart failure, cardiomyopathies, and congenital heart disease.

Correlation of left ventricular myocardial work indices with invasive measurement of stroke work in patients with advanced heart failure

Objectives

This study aimed to explore the correlation between left ventricular (LV) myocardial work (MW) indices and invasively-derived LV stroke work index (SWI) in a cohort of patients with advanced heart failure (AHF) considered for heart transplantation.

Background

Left ventricular MW has emerged as a promising tool for diagnostic and prognostic purposes in heart failure (HF) but its relationship with hemodynamic data derived from right heart catheterization (RHC) has not been assessed in patients with advanced heart failure yet.

Materials and methods

Consecutive patients with AHF considered for heart transplantation from 2016 to 2021 performing RHC and echocardiography as part of the workup were included. Conventional LV functional parameters and LV MW indices, including LV global work index (GWI), LV global constructive work (GCW), LV global wasted work (GWW), LV global work efficiency (GWE), and other were calculated and compared with invasively-measured LV SWI.

Results

The population included 44 patients. Median time between RHC and echocardiography was 0 days (IQR: 0–24). Median age was 60 years (IQR: 54–63). For the most part, etiology of HF was non-ischemic (61.4%) and all patients were either on class NYHA II (61.4%) or III (27.3%). Median left ventricular ejection fraction was 25% (IQR: 22.3–32.3), median NT-proBNP 1,377 pg/ml (IQR: 646–2570). LV global longitudinal strain (GLS) significantly correlated with LV SWI (r = –0.337; p = 0.031), whereas, LV ejection fraction (EF) did not (r = 0.308; p = 0.050). With regard to LV MW indices, some of them demonstrated correlation with LV SWI, particularly LV GWI (r = 0.425; p = 0.006), LV GCW (r = 0.506; p = 0.001), LV global positive work (LV GPW; r = 0.464; p = 0.003) and LV global systolic constructive work (GSCW; r = 0.471; p = 0.002).

Conclusion

Among LV MW indices, LV GCW correlated better with invasively-derived SWI, potentially representing a powerful tool for a more comprehensive evaluation of myocardial function.

The basic heart anatomy and physiology from the cardiologist's perspective: Toward a better understanding of left ventricular mechanics, systolic, and diastolic function

A comprehensive understanding of the cardiac structure-function relationship is essential for proper clinical cardiac imaging. This review summarizes the basic heart anatomy and physiology from the perspective of a heart imager focused on myocardial mechanics. The main issues analyzed are the left ventricular (LV) architecture, the LV myocardial deformation through the cardiac cycle, the LV diastolic function basic parameters and the basic parameters of the LV deformation used in clinical practice for the LV function assessment.

Effects of postsystolic shortening and diastolic dyssynchrony on myocardial work in untreated early hypertension patients

OBJECTIVES

Myocardial work is estimated from noninvasive pressure-strain loop for advanced assessment of left ventricular function. Postsystolic shortening and diastolic dyssynchrony of left ventricle were noted early in hypertension. Their novel effects on myocardial work will be illustrated in this study.

METHODS

We recruited 43 newly diagnosed hypertensive patients (mean age 51.3 ± 12.5 years, 55.8% men) and 32 age-matched and sex-matched healthy individuals (mean age 52.7 ± 10.5 years, 37.5% men) as control. Pressure-strain loop derived myocardial work incorporated global longitudinal strain from speckle tracking echocardiography with brachial artery cuff pressure. Postsystolic strain index (PSI) was defined by the percentage of postsystolic shortening over peak strain. Diastolic dyssynchrony was assessed by standard deviation of time to peak early diastolic strain rate (TDSr-SD) of 18 segments, and maximal difference of time to peak early diastolic strain rate (TDSr-MD) between any two segments.

RESULTS

After multivariate regression analysis, global myocardial work index (GWI) was independently correlated with TDSr-SD (B = -0.498, P = 0.001) and TDSr-MD (B = -0.513, P = 0.001). Global myocardial constructive work (GCW) was independently correlated with TDSr-SD (B = -0.334, P = 0.025) and TDSr-MD (B = -0.397, P = 0.007). Global myocardial wasted work (GWW) was independently correlated with PSI (B = 0.358, P = 0.019). Global myocardial work efficiency (GWE) was lower in hypertensive patients than healthy control (P = 0.001). The untreated hypertensive patients were different from the healthy individuals with higher TDSr-SD, TDSr-MD, GWI, GCW, GWW, and PSI (all P < 0.05).

CONCLUSION

In conclusion, the effect of diastolic dyssynchrony mainly influenced constructive work, whereas postsystolic shortening affected wasted work in early untreated hypertension.

Myocardial Work in Patients Hospitalized With COVID-19: Relation to Biomarkers, COVID-19 Severity, and All-Cause Mortality

Background COVID-19 infection has been hypothesized to affect left ventricular function; however, the underlying mechanisms and the association to clinical outcome are not understood. The global work index (GWI) is a novel echocardiographic measure of systolic function that may offer insights on cardiac dysfunction in COVID-19. We hypothesized that GWI was associated with disease severity and all-cause death in patients with COVID-19. Methods and Results In a multicenter study of patients admitted with COVID-19 (n=305), 249 underwent pressure-strain loop analyses to quantify GWI at a median time of 4 days after admission. We examined the association of GWI to cardiac biomarkers (troponin and NT-proBNP [N-terminal pro-B-type natriuretic peptide]), disease severity (oxygen requirement and CRP [C-reactive protein]), and all-cause death. Patients with elevated troponin (n=71) exhibited significantly reduced GWI (1508 versus 1707 mm Hg%; P=0.018). A curvilinear association to NT-proBNP was observed, with increasing NT-proBNP once GWI decreased below 1446 mm Hg%. Moreover, GWI was significantly associated with a higher oxygen requirement (relative increase of 6% per 100-mm Hg% decrease). No association was observed with CRP. Of the 249 patients, 37 died during follow-up (median, 58 days). In multivariable Cox regression, GWI was associated with all-cause death (hazard ratio, 1.08 [95% CI, 1.01-1.15], per 100-mm Hg% decrease), but did not increase C-statistics when added to clinical parameters. Conclusions In patients admitted with COVID-19, our findings indicate that NT-proBNP and troponin may be associated with lower GWI, whereas CRP is not. GWI was independently associated with all-cause death, but did not provide prognostic information beyond readily available clinical parameters. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT04377035.

Specific alterations of regional myocardial work in strength-trained athletes using anabolic steroids compared to athletes with genetic hypertrophic cardiomyopathy

PURPOSE

Strength-trained athletes using anabolic androgenic steroids (AAS) have left ventricular (LV) hypertrophy and myocardial fibrosis that can lead to sudden cardiac death. A similar feature was described in athletes with hypertrophic cardiomyopathy (HCM), which complicates the diagnosis for clinicians. In this context, we aimed to compare the LV function of the 2 populations by measuring global and regional strain and myocardial work using speckle-tracking imaging.

METHODS

Twenty-four strength-trained asymptomatic athletes using AAS (AAS-Athletes), 22 athletes diagnosed with HCM (HCM-Athletes), and 20 healthy control athletes (Ctrl-Athletes) underwent a resting echocardiography to assess LV function. We evaluated LV global and regional strains and myocardial work, with an evaluation of the constructive work (CW), wasted work, and work efficiency (WE).

RESULTS

Compared to Ctrl-Athletes, both AAS-Athletes and HCM-Athletes had a thicker interventricular septum, with majored values in HCM-Athletes. LV strain was reduced in AAS-Athletes and even more in HCM-Athletes. Consequently, global WE was significantly diminished in both AAS and HCM-Athletes (93% ± 2% in Ctrl-Athletes, 90% ± 4% in AAS-Athletes, and 90% ± 5% in HCM-Athletes (mean ± SD); p < 0.05). Constructive work and WE regional analysis showed specific alterations, with the basal septal segments preferentially affected in AAS-Athletes, and both septal and apical segments affected in HCM-Athletes.

CONCLUSION

The regional evaluation of myocardial work reported specific alterations of the major LV hypertrophy induced by the regular use of AAS compared to the LV hypertrophy due to HCM. This finding could help clinicians to differentiate between these 2 forms of pathological hypertrophy.

Phenotyping the hypertensive heart

Arterial hypertension remains the most frequent cardiovascular (CV) risk factor, and is responsible for a huge global burden of disease. Echocardiography is the first-line imaging method for the evaluation of cardiac damage in hypertensive patients and novel techniques, such as 2D and D speckle tracking and myocardial work, provide insight in subclinical left ventricular (LV) impairment that would not be possible to detect with conventional echocardiography. The structural, functional, and mechanical cardiac remodelling that are detected with imaging are intermediate stages in the genesis of CV events, and initiation or intensification of antihypertensive therapy in response to these findings may prevent or delay progressive remodelling and CV events. However, LV remodelling—especially LV hypertrophy—is not specific to hypertensive heart disease (HHD) and there are circumstances when other causes of hypertrophy such as athlete heart, aortic stenosis, or different cardiomyopathies need exclusion. Tissue characterization obtained by LV strain, cardiac magnetic resonance, or computed tomography might significantly help in the distinction of different LV phenotypes, as well as being sensitive to subclinical disease. Selective use of multimodality imaging may therefore improve the detection of HHD and guide treatment to avoid disease progression. The current review summarizes the advanced imaging tests that provide morphological and functional data about the hypertensive cardiac injury.

Clinical significance of myocardial work parameters after acute myocardial infarction

Aims

To investigate the additional prognostic value of myocardial work (MW) parameters following acute myocardial infarction (AMI).

Methods and results

Between 2018 and 2020, 244 patients admitted in the cardiac intensive care unit in Lille University Hospital for AMI were included. One-month following AMI, comprehensive transthoracic echocardiography (TTE) was performed to assess parameters of myocardial function. Patients were then followed for major events (ME): cardiovascular death, heart failure, and unplanned coronary revascularization. At 1-month, half of the population was symptomatic (NYHA ≥ II), and medical therapy was almost optimized (angiotensin-converting enzyme inhibitor/angiotensin 2 receptor blocker in 95.5%, beta-blockers in 96.3%, DAPT in 94.7%, and statins in 97.1%). After a median follow-up of 681 (interquartile range: 538–840) days, ME occurred in 26 patients (10.7%). Patients presenting ME were older (65.5 ± 14.2 vs. 58.1 ± 12.1years, P = 0.005) with a higher prevalence of hypertension (65.4 vs. 36.2%, P = 0.004), more impaired left ventricular (LV) function as assessed by LV ejection fraction (P = 0.07), global longitudinal strain (P = 0.03), or MW parameters [P = 0.01 for global work efficiency (GWE)], and greater LV and left atrium dilatations (P = 0.06 for left ventricular end-diastolic volume index and P = 0.03 for left atrial volume index). After adjustment, GWE was the only TTE parameter independently associated with long-term occurrence of ME (P = 0.02). A GWE value <91% was selected to identify patients at higher ME risk (hazard ratio: 95% confidence interval) = 2.94 (1.36–6.35), P = 0.0041).

Conclusion

Lower GWE at 1 month after AMI is independently associated with higher ME rates. A GWE <91% can improve the post-AMI patient risk stratification.

Assessment of Myocardial Work of the Left Ventricle before and after PCI in Patients with Non-ST-Segment Elevation Acute Coronary Syndrome by Pressure-Strain Loop Technology

Objectives

Noninvasive left ventricular pressure-strain loop (PSL) is a new method for quantitative evaluation of myocardial work, which is developed on the basis of speckle tracking echocardiography. It is necessary to fit the noninvasive left ventricular pressure and the strain by speckle tracking echocardiography to construct a pressure-strain loop. Compared with traditional left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS), it has potential application value and is a useful supplement for clinical evaluation of left ventricular systolic function. We perform this study to evaluate the changes of myocardial function in patients with non-ST-segment elevation acute coronary syndrome (NSTE-ACS) before and after percutaneous coronary intervention (PCI) with noninvasive left ventricular pressure-strain loop (PSL).

Methods

33 NSTE-ACS patients admitted to the Department of Cardiovascular Medicine of the Affiliated Lianyungang Hospital of Xuzhou Medical University who successfully underwent early PCI were included as the PCI group. At the same time, 30 healthy patients matched in age and sex were selected as the control group. All patients received routine echocardiography. The parameters such as GWI, GCW, GWW, and GWE were obtained by EchoPAC 203 software. The differences in the general clinical data and echocardiographic parameters between the two groups, including controls and patients 1 day before surgery and 1 month after surgery, were compared.

Results

Compared with the control group, GWI, GCW, and GWI in the PCI group were decreased 1 day before surgery and 1 month after surgery, while GWW was increased, with statistical significance (P < 0.05). In the PCI group, compared with 1 day before surgery, GWI and GCW were all increased 1 month after surgery (P < 0.05), and GWW and GWE were not significantly different between the two groups (P > 0.05).

Conclusion

The noninvasive left ventricular PSL technology can early and accurately evaluate the myocardial function impairment in NSTE-ACS patients and the recovery of myocardial function after PCI, providing a new noninvasive method for clinical postoperative myocardial function evaluation.

Echocardiographic study of myocardial work in patients with type 2 diabetes mellitus

Background

A noninvasive left ventricular (LV) pressure-strain loop (PSL) provides a new method to quantify myocardial work (MW) by combining global longitudinal strain (GLS) and LV pressure, which exerts potential advantages over traditional GLS. We studied the LV PSL and MW in patients with type 2 diabetes mellitus (T2DM).

Methods

This cross-sectional study included 201 subjects (54 healthy controls and 147 T2DM patients) who underwent complete two-dimensional echocardiography (2DE), including 2D speckle-tracking echocardiography (STE), as well as brachial artery pulse pressure measurement. The PSL was used to determine the global myocardial work index (GWI), global constructive work (GCW), global wasted work (GWW), and global work efficiency (GWE) of all study participants. The association between T2DM and LV function was evaluated according to these MW indices.

Results

The GLS was significantly lower in the T2DM group than in the control group (P < 0.001), indicating that the LV myocardium had been damaged, although the LV ejection fraction (LVEF) was still normal. The GWI and GWE were decreased (P = 0.022) and the GWW was increased (P < 0.001) in diabetic patients compared with controls, but the GCW was comparable in the two groups (P = 0.160). In all diabetic patients, age, body mass index, systolic blood pressure, smoking history, and LVEF were correlated with GWI, GWW and GWE.

Conclusions

The use of LV PSL is a novel noninvasive technique that could help to depict the relationship between LV myocardial damage and MW in patients with T2DM.

Left Ventricular Strains and Myocardial Work in Adolescents With Anorexia Nervosa

Background

Anorexia nervosa (AN) is accompanied by bradycardia, low blood pressure (BP) and cardiac morphological remodeling. Systolic and diastolic functions are relatively preserved when assessed by standard ultrasound methods. However, novel advances based on speckle tracking echocardiography (STE), that could detect subtle and early alterations of left ventricular (LV) function, remained poorly used in AN patients.

Objective

The aim of this study was to assess the cardiac function of AN patients by evaluating LV myocardial strains, myocardial work (MW) and LV mechanical dispersion. We hypothesized that LV strains and global myocardial work would be decreased and LV twisting mechanisms enhanced to preserve the systolic function.

Methods

Fifty-nine adolescents including 26 women AN patients (14.6 ± 1.9 yrs. old) with a mean duration of AN of 19 ± 9 months and 33 controls (14.1 ± 2.0 yrs. old) underwent STE to assess LV morphology and myocardial regional strains.

Results

The global longitudinal strain (GLS) was higher in AN patients compared to controls (−18.8 ± 2.0 vs. −16.9 ± 2.8%, p = 0.006). The area under the pressure-strain loop, representing the global MW was not altered but was shifted to the left and downwards in AN patients, due to their lower BP and higher GLS. Intraventricular mechanical dispersion was similar in both groups. Circumferential strains, twisting/untwisting mechanics were preserved.

Conclusion

Our results strongly support that the cardiac morphological remodeling observed in our AN patients was associated with normal ventricular regional myocardial functions. Only GLS was higher in AN patients, but its clinical significance remains to be demonstrated.

Comparison of Myocardial Layer-Specific Strain and Global Myocardial Work Efficiency During Treadmill Exercise Stress in Detecting Significant Coronary Artery Disease

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.

Strain and myocardial work index during echo exercise to evaluate myocardial function in athletes

The aim of the study was to evaluate the application of global longitudinal strain (GLS) and myocardial work (MW) at rest and during exercise in healthy sedentary or trained participants, to test their ability to improve echocardiographic information and to complement prescribing exercise, cardiac screening, or rehabilitation programs.

Reference Values of Noninvasive Myocardial Work Indices Measured by Echocardiography in Healthy Children

BACKGROUD

Noninvasive myocardial work, estimated by left ventricular (LV) pressure-strain loop (PSL), has been introduced for assessing LV myocardial performance. Based on both blood pressure and speckle-tracking derived strain data, noninvasive myocardial work is considered to be less load-dependent than global longitudinal strain (GLS). In some conditions, such as hypertension or aortic coarctation, the increased afterload will affect strain measurements, and myocardial work can serve as a more robust metric.

OBJECTIVE

We prospectively recruited healthy children to explore the relationship between myocardial work indices and body size parameters, and to determine the reference values of noninvasive myocardial work indices in healthy children.

METHODS

183 healthy children (aged 1-18 years, males: 52.5%) were enrolled in the study. Global work index (GWI), global constructive work (GCW), global wasted work (GWW), global work efficiency (GWE), were assessed by LVPSL and compared according to age and sex.

RESULTS

The mean for GWI was 1,448.7 ± 265.0 mm Hg%, 1,859.8 ± 290.7 mm Hg% for GCW, and the median (interquartile range) for GWW was 54.0 (33.0-82.0) mm Hg% and 97.0 (95.0-99.0) % for GWE. male had greater GWI and GCW) than female (1,572.5 ± 250.2 mm Hg% vs. 1,312.2 ± 208.7 mm Hg% and 1,944.3 ± 299.2 mm Hg% vs. 1,766.6 ± 251.5 mm Hg%, respectively, all P < 0.001). GWI and GCW were significantly correlated with baseline parameters, including age, height, weight, BSA, body mass index, heart rate, and blood pressure. After indexed to BSA, GWI (BSA), GCW (BSA) remained significantly negatively correlated with age (P < 0.001).

CONCLUSIONS

we proposed the normal reference values and regression equations for GWI and GCW based on age and BSA in healthy children. This might provide a basis of reference for the evaluation of cardiac function in children with cardiopulmonary disease.

Application value of myocardial work technology by non-invasive echocardiography in evaluating left ventricular function in patients with chronic heart failure

BACKGROUND

Accurate evaluation of left ventricular (LV) systolic function is the premise for diagnosing and treating chronic heart failure. This study aimed to explore the incremental value of echocardiographic myocardial work in evaluating the LV systolic dysfunction in patients with chronic heart failure.

METHODS

A total of 206 participants were enrolled, including 155 patients with chronic heart failure and 51 healthy controls (HC). The chronic heart failure patients were divided into three groups according to LV ejection fraction (LVEF): Heart failure with preserved ejection fraction (HFpEF group, 54 cases, LVEF ≥50%), heart failure with mid-range ejection fraction (HFmrEF group, 50 cases, 40%≤ LVEF <50%), and heart failure with reduced ejection fraction (HFrEF group, 51 cases, LVEF <40%). Except for the conventional echocardiographic parameters, the left ventricular myocardial work parameters, including the global myocardial work index (GWI), global constructive work (GCW), global wasted work (GWW), and global work efficiency (GWE), were calculated in the study participants. One-way analysis of variance test followed by Fisher's least significant difference (LSD) t-test were used to obtain parameters with significant differences, which were then fed into a machine learning model established for subsequent multi-classification of the four groups. The selected myocardial work parameters with high importance rankings resulting from the machine learning model were further compared with the traditional LVEF in the multi-classification of the four groups.

RESULTS

All conventional echocardiographic parameters were significantly different between the HFmrEF and HFrEF groups, but only E/e', left atrium showed notable differences between the HFpEF and HC groups (P<0.05). All myocardial work parameters were markedly different between the four groups (P<0.05). LVEF and GWI were more important than the other parameters according to the multi-classification machine learning model. The multi-classification diagnostic performances of LVEF, GWI, and LVEF + GWI were 82%, 88%, and 98%, respectively, which confirmed that GWI + LVEF could complementarily improve the diagnosis accuracy in classifying the four groups, with a performance increase of approximately 10% than each individually.

CONCLUSIONS

GWI can play a complementary role to LVEF in the early diagnosis of HFpEF patients from the HC group and improve the clinical evaluation accuracy in chronic heart failure patients. Echocardiographic myocardial work should be utilized along with conventional LVEF to evaluate the systolic function of chronic heart failure patients in clinical practice.

Performance of non-invasive myocardial work to predict the first hospitalization for de novo heart failure with preserved ejection fraction

AIMS

Non-invasive myocardial work (MW) is a validated index of left ventricular (LV) systolic performance, incorporating afterload and myocardial metabolism. The role of MW in predicting the first hospitalization for de novo heart failure with preserved ejection fraction (HFpEF) is still unknown. We aim to investigate the diagnostic performance of MW to predict the first de novo HFpEF hospitalization in ambulatory individuals with preserved LV ejection fraction.

METHODS AND RESULTS

Twenty-nine patients with transthoracic echocardiography performed at least 6 months before the first HFpEF hospitalization were compared with 29 matched controls. MW was derived as the area of pressure-strain loop using speckle-tracking and brachial artery blood pressure. Global work index, global constructive work, global wasted work (GWW), and global work efficiency (GWE) were collected. First HFpEF hospitalization and its combination with cardiovascular death [major adverse cardiovascular events (MACE)] and all-cause of death [major adverse events (MAE)] were assessed. At baseline, future HFpEF patients showed lower global work index, global constructive work, GWE, and higher GWW than controls (all P < 0.05). At admission vs. baseline, GWE significantly decreased, and GWW increased in the HFpEF group (P < 0.05), whereas no significant difference was observed in the controls over time. GWW, with a cut-off of 170 mmHg%, showed the largest area under the curve (AUC) to predict first HFpEF hospitalization [AUC = 0.80, 95% confidence interval (CI) 0.69-0.91, P < 0.001], MACE (AUC = 0.80, 95% CI 0.66-0.90, P < 0.001), and MAE (AUC = 0.79, 95% CI 0.62-0.88, P = 0.001). GWW > 170 mmHg% was associated with a 4-fold increase of MACE (HR = 4.5, 95% CI 1.59-13.12, P = 0.005) and a 3-fold higher risk of MAE (HR = 2.9, 95% CI 1.24-6.6, P = 0.014).

CONCLUSIONS

In ambulatory patients with preserved LV ejection fraction and risk factors, GWW showed high accuracy to predict the first HFpEF hospitalization and its combination with mortality. The GWW routine assessment may be clinically helpful in patients with dyspnoea.