Evolution of cardiac tissue and flow mechanics in developing Japanese Medaka

The effects of pressure drop across cardiac valve cushion regions and endocardial wall strain in the early developmental stages of a teleost species heart are poorly understood. In the presented work, we utilize microscale particle image velocimetry (μPIV) flow measurements of developing medaka hearts from 3 to 14 dpf (n = 5 at each dpf) to quantify the pressure field and endocardial wall strain. Peak pressure drop at the atrioventricular canal (ΔPAVC) and outflow tract (ΔPOFT) show a steady increase with fish age progression. Pressure drops when non-dimensionalized with blood viscosity and heart rate at each dpf are comparable with measurements in zebrafish hearts. Retrograde flows captured at these regions display a negative pressure drop. A novel metric, Endocardial Work (EW), is introduced by analyzing the ΔPAVC-strain curves, which is a non-invasive measure of work required for ventricle filling. EW is a metric that can differentiate between the linear heart stage (< 100 Pa-%), cardiac looped chamber stage (< 300 Pa-%), and the fully formed chamber stage (> 300 Pa-%).

Role of speckle tracking echocardiography beyond current guidelines in cardiac resynchronization therapy

Cardiac resynchronization therapy (CRT) is a device-based treatment applied to patients with a specific profile of heart failure. According to current guidelines, indication for CRT is given on the basis of QRS morphology and duration, and traditional transthoracic echocardiography is mainly used to estimate left ventricular (LV) ejection fraction. However, the identification of patients who may benefit from CRT remains challenging, since the application of the above-mentioned guidelines is still associated with a high rate of non-responders. The assessment of various aspects of LV mechanics (including contractile synchrony, coordination and propagation, and myocardial work) performed by conventional and novel ultrasound technologies, first of all speckle tracking echocardiography (STE), may provide additional, useful information for CRT patients' selection, in particular among non-LBBB patients, who generally respond less to CRT. A multiparametric approach, based on the combination of ECG criteria and echocardiographic indices of LV dyssynchrony/discoordination would be desirable to improve the prediction of CRT response.

Myocardial work indices in bileaflet mitral valve prolapse patients

AIMS

Mechanisms underlying left ventricular dysfunction and arrhythmogenesis in bileaflet mitral valve prolapse (BMVP) patients are not well defined. Myocardial work index (MWI) is a non-invasive assessment that correlates with myocardial oxygen consumption. We aimed to compare global and regional MWI in BMVP patients with normal controls.

METHODS AND RESULTS

In this retrospective study, we calculated MWI in BMVP patients and controls using GE EchoPAC (GE Healthcare, Chicago, IL, USA) software. Of 147 BMVP patients (59% women, mean age 54 ± 15 years), 16 had a flail mitral leaflet. There was regional heterogeneity in MWIs, with increased posterolateral trident myocardial work (2099 ± 271 vs. 1895 ± 321 mm Hg%, P = 0.039), constructive work (2831 ± 366 vs. 2257 ± 338 mm Hg%, P < 0.001), wasted work [87 (52-194) vs. 71 (42-103) mm Hg%, P = 0.015], peak systolic strain (-23.0 ± 2.4 vs. -19 ± 3%, P < 0.001), and reduction in myocardial work efficiency [95.00 (93.50-97.75) vs. 96.75 (95.00-97.75) %, P = 0.020] in 100 BMVP patients compared with age- and sex-matched controls. BMVP patients' basal septal wall MWIs were lower than those of controls. The higher work indices in patients with BMVP were reduced in those who developed flail leaflets. No significant differences in work indices were seen between ventricular arrhythmia and non-arrhythmia BMVP patients.

CONCLUSION

Regional differences in MWIs were noted in the BMVP patients compared with controls, with overall reduced myocardial efficiency in the posterolateral trident and basal septal regions. In cross-sectional analysis, MWIs were not different in patients with ventricular tachyarrhythmias. Impact of MWI on long-term prognosis needs to be determined.

Moving from left ventricular ejection fraction to deformation imaging in mitral valve regurgitation

The increasing prevalence of valvular heart diseases, specifically mitral regurgitation (MR), underscores the need for a careful and timely approach to intervention. Severe MR, whether primary or secondary, when left untreated leads to adverse outcomes, emphasizing the critical role of a timely surgical or transcatheter intervention. While left ventricular ejection fraction (LVEF) remains the guideline-recommended measure for assessing left ventricle damage, emerging evidence raises concerns regarding its reliability in MR due to its volume-dependent nature. This review summarizes the existing literature on the role of LVEF and deformation imaging techniques, emphasizing the latter's potential in providing a more accurate evaluation of intrinsic myocardial function. Moreover, it advocates the need for an integrated approach that combines traditional with emerging measures, aiming to optimize the management of patients with MR. It attempts to highlight the need for future research to validate the clinical application of deformation imaging techniques through large-scale studies.

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.

Clinical significance of regional constructive and wasted work in patients receiving cardiac resynchronization therapy

Background

Previous studies have shown that global constructive work (CW) and wasted work (WW) predict response to cardiac resynchronization therapy (CRT). This study evaluated the predictive value of regional CW and WW for reverse remodeling and clinical outcomes after CRT.

Methods

We performed a prospective study involving 134 CRT candidates with left bundle branch block and left ventricular ejection fraction ≤35%. Global and regional CW and WW were calculated using pressure-strain loop analysis. CRT response was defined by reverse remodeling as a reduction of ≥15% in left ventricular end-systolic volume after six months.

Results

At six-month follow-up, 92 (69%) patients responded to CRT. Of the regional CW and WW measures, lateral wall (LW) CW and septal WW were most strongly and significantly correlated with reverse remodeling. At multivariate analysis, LW CW and septal WW were both independent determinants of reverse remodeling. When LW CW and septal WW were included in the model, global CW and WW were not independently associated with reverse remodeling. LW CW and septal WW predicted reverse remodeling with an area under the curve (AUC) of 0.783 (95% CI: 0.700-0.866) and 0.737 (95% CI: 0.644-0.831), respectively. Using both variables increased the AUC to 0.832 (95% CI: 0.755-0.908). Both LW CW ≤878 mmHg% (HR 2.01; 95% CI: 1.07-3.79) and septal WW ≤181 mmHg% (HR 2.60; 95% CI: 1.38-4.90) were significant predictors of combined death and HF hospitalization at two-year follow-up.

Conclusion

LW CW and septal WW before CRT are important determinants of reverse remodeling and clinical outcomes.

Understanding the Application of Mechanical Dyssynchrony in Patients with Heart Failure Considered for CRT

Over the past two decades of CRT use, the failure rate has remained around 30-35%, despite several updates in the guidelines based on the understanding from multiple trials. This review article summarizes the role of mechanical dyssynchrony in the selection of heart failure patients for cardiac resynchronization therapy. Understanding the application of mechanical dyssynchrony has also evolved during these past two decades. There is no role of lone mechanical dyssynchrony in the patient selection for CRT. However, mechanical dyssynchrony can complement the electrocardiogram and clinical criteria and improve patient selection by reducing the failure rate. An oversimplified approach to mechanical dyssynchrony assessment, such as just estimating time-to-peak delays between segments, should not be used. Instead, methods that can identify the underlying pathophysiology of HF and are representative of a substrate to CRT should be applied.

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.

Myocardial strain of the left ventricle by speckle tracking echocardiography: From physics to clinical practice

Speckle tracking echocardiography (STE) is a reliable imaging technique of recognized clinical value in several settings. This method uses the motion of ultrasound backscatter speckles within echocardiographic images to derive myocardial velocities and deformation parameters, providing crucial insights on several cardiac pathological and physiological processes. Its feasibility, reproducibility, and accuracy have been widely demonstrated, being myocardial strain of the various chambers inserted in diagnostic algorithms and guidelines for various pathologies. The most important parameters are Global longitudinal strain (GLS), Left atrium (LA) reservoir strain, and Global Work Index (GWI): based on large studies the average of the lower limit of normality are -16%, 23%, and 1442 mmHg%, respectively. For GWI, it should be pointed out that myocardial work relies primarily on non-invasive measurements of blood pressure and segmental strain, both of which exhibit high variability, and thus, this variability constitutes a significant limitation of this parameter. In this review, we describe the principal aspects of the theory behind the use of myocardial strain, from cardiac mechanics to image acquisition techniques, outlining its limitation, and its principal clinical applications: in particular, GLS have a role in determine subclinical myocardial dysfunction (in cardiomyopathies, cardiotoxicity, target organ damage in ambulatory patients with arterial hypertension) and LA strain in determine the risk of AF, specifically in ambulatory patients with arterial hypertension.

Position Statement on the Use of Myocardial Strain in Cardiology Routines by the Brazilian Society of Cardiology's Department Of Cardiovascular Imaging - 2023

Central Illustration : Position Statement on the Use of Myocardial Strain in Cardiology Routines by the Brazilian Society of Cardiology's Department Of Cardiovascular Imaging - 2023 Proposal for including strain in the integrated diastolic function assessment algorithm, adapted from Nagueh et al.67 Am: mitral A-wave duration; Ap: reverse pulmonary A-wave duration; DD: diastolic dysfunction; LA: left atrium; LASr: LA strain reserve; LVGLS: left ventricular global longitudinal strain; TI: tricuspid insufficiency. Confirm concentric remodeling with LVGLS. In LVEF, mitral E wave deceleration time < 160 ms and pulmonary S-wave < D-wave are also parameters of increased filling pressure. This algorithm does not apply to patients with atrial fibrillation (AF), mitral annulus calcification, > mild mitral valve disease, left bundle branch block, paced rhythm, prosthetic valves, or severe primary pulmonary hypertension.

Cardiac reverse remodelling by imaging parameters with recent changes to guideline medical therapy in heart failure

Recently established heart failure therapies, including sodium glucose co-transporter 2 inhibitors, angiotensin-neprilysin inhibitors, and cardiac resynchronization therapy, have led to both clinical and structural improvements. Reverse remodelling describes the structural and functional responses to therapy and has been shown to correlate with patients' clinical response, acting as a biomarker for treatment success. The introduction of these new therapeutic agents in addition to advances in non-invasive cardiac imaging has led to an expansion in the evaluation and the validation of cardiac reverse remodelling. Methods including volumetric changes as well as strain and myocardial work have all been shown to be non-invasive end-points of reverse remodelling, correlating with clinical outcomes. Our review summarizes the current available evidence on reverse remodelling in heart failure by the non-invasive cardiac imaging techniques, in particular transthoracic echocardiography.

Association Between Segmental Noninvasive Myocardial Work and Microvascular Perfusion in ST-Segment Elevation Myocardial Infarction: Implications for Left Ventricular Functional Recovery and Clinical Outcomes

BACKGROUND

Predicting left ventricular recovery (LVR) after acute ST-segment elevation myocardial infarction (STEMI) is of prognostic importance. This study aims to explore the prognostic implications of segmental noninvasive myocardial work (MW) and microvascular perfusion (MVP) after STEMI.

METHODS

In this retrospective study, 112 patients with STEMI who underwent primary percutaneous coronary intervention and transthoracic echocardiography after percutaneous coronary intervention were enrolled. Microvascular perfusion was analyzed by myocardial contrast echocardiography, and segmental MW was analyzed by noninvasive pressure-strain loops. A total of 671 segments with abnormal function at baseline were analyzed. The degrees of MVP were observed following intermittent high-mechanical index impulses: replenishment within 4 seconds (normal MVP), replenishment >4 seconds and within 10 seconds (delayed MVP), and persistent defect (microvascular obstruction). The correlation between MW and MVP was analyzed. The correlation of the MW and MVP with LVR (normalization of wall thickening, >25%) was assessed. The prognostic value of segmental MW and MVP for cardiac events (cardiac death, admission for congestive heart failure, or recurrent myocardial infarction) was evaluated.

RESULTS

Normal MVP was seen in 70 segments, delayed MVP in 236, and microvascular obstruction in 365. The segmental MW indices were independently correlated with MVP; 244 (36.4%) segments had segmental LVR at 3-month follow-up. Segmental MW efficiency and MVP were independently associated with segmental LVR (P < .05). The χ2 of combination of segmental MW efficiency and MVP was higher than either index alone for identifying segmental LVR (P < .001). At a median follow-up of 42.0 months, cardiac events occurred in 13 patients; all regional MW parameters, high sensitivity troponin I, regional longitudinal strain, and so on were associated with cardiac events.

CONCLUSIONS

Segmental MW indices are associated with MVP within the infarct zone following reperfused STEMI. Both are independently associated with segmental LVR, and regional MW is associated with cardiac events, providing prognostic value in STEMI patients.

Myocardial Work in Apical Hypertrophic Cardiomyopathy

BACKGROUND

Pressure-strain loop analysis is a novel echocardiographic technique to calculate myocardial work indices that has not been applied to patients with apical hypertrophic cardiomyopathy (ApHCM). We hypothesized that myocardial work indices differ between patients with ApHCM and those with non-ApHCM. This study aimed to (1) evaluate myocardial work indices in patients with ApHCM compared with those with non-ApHCM, (2) describe associations with relevant clinical variables, and (3) examine associations with significant late gadolinium enhancement (LGE) on cardiac magnetic resonance imaging.

METHODS

We retrospectively identified 48 patients with ApHCM and 69 with non-ApHCM who had measurements of global longitudinal strain (GLS), global work index (GWI), global constructive work (GCW), global wasted work, and global work efficiency. We evaluated available cardiac magnetic resonance imaging data on 34 patients with ApHCM and 51 with non-ApHCM. Multivariable regression models correcting for traditional cardiac risk factors were used to evaluate the associations of myocardial work indices with relevant clinical variables.

RESULTS

Median GLS (-11% vs -18%, P < .001), GWI (966 mm Hg% vs 1803 mm Hg%, P < .001), and GCW (1,050 mm Hg% vs 1,988 mm Hg%, P < .001) were significantly impaired in patients with ApHCM compared with those with non-ApHCM. Increasing N-terminal pro b-type natriuretic peptide, abnormal ultrasensitive troponin, and increasing maximal left ventricular wall thickness were significantly associated with reduced GWI and GCW in patients with ApHCM (P < .05). Global constructive work had only modest accuracy (area under the curve [AUC] = 0.70) to predict LGE in patients with ApHCM. However, in patients with non-ApHCM, GLS was the strongest predictor of LGE (AUC = 0.91), with a -17% cutoff yielding 81% sensitivity and 80% specificity.

CONCLUSION

Myocardial work indices are significantly impaired in patients with ApHCM compared to those with non-ApHCM and correlate with important clinical variables. Global longitudinal strain, GWI, and GCW are more strongly predictive of fibrosis in patients with non-ApHCM than ApHCM.

Beyond Conventional Cardiac Resynchronisation Therapy: A Review of Electrophysiological Options in the Management of Chronic Heart Failure

The incidence of heart failure (HF) continues to grow and burden our health care system. Electrophysiological aberrations are common amongst patients with heart failure and can contribute to worsening symptoms and prognosis. Targeting these abnormalities with cardiac and extra-cardiac device therapies and catheter ablation procedures augments cardiac function. Newer technologies aimed to improvement procedural outcomes, address known procedural limitations and target newer anatomical sites have been trialled recently. We review the role and evidence base for conventional cardiac resynchronisation therapy (CRT) and its optimisation, catheter ablation therapies for atrial arrhythmias, cardiac contractility and autonomic modulation therapies.

Myocardial work-A new tool for early detection of rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone chemotherapy induced-cardiotoxicity in hematological patients

BACKGROUND

Rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone (RCHOP) chemotherapy in non-Hodgkin's lymphoma (NHL) has risk of cardiotoxicity.

PURPOSE

To determine the role of myocardial work and biomarkers in subclinical diagnosis and prediction of cardiotoxicity.

METHODS

The 130 NHL patients (52 ± 9 years, 62% men) scheduled for RCHOP, with LVEF>50%, were evaluated at baseline, after third cycle and chemotherapy completion for 3D LVEF, 2D myocardial deformation (longitudinal, radial, circumferential strain - LS, RS, CS) and myocardial work (global constructive work, waste work, work index and work efficiency - GCW, GWW, GWI, GWE). NT-pro-BNP and troponin I were determined.

RESULTS

After chemotherapy ended, 37 patients (28%) (group I) developed asymptomatic cardiotoxicity (8 mild form, 25 moderate form, 4 severe form); 93 patients (group II) did not. After third cycle, all patients had decreased LS, CS, RS, GCW, GWI, GWE and increased GWW, persistent after chemotherapy completion, with significant changes in group I. After third cycle, GWE and GCW were the best independent predictors for LVEF reduction; GWE decrease with>5% after third cycle predicted cardiotoxicity after chemotherapy completed (91% sensitivity, 94% specificity).

CONCLUSIONS

In NHL, myocardial work can diagnose subclinical cardiotoxicity and predict LVEF decline. These parameters should be used for sensitive evaluation of myocardial function during chemotherapy.

Apply pressure-strain loop to quantify myocardial work in pulmonary hypertension: A prospective cohort study

Objectives

Pressure-strain loop (PSL) is a novel method to quantify myocardial work in many cardiovascular diseases. To investigate the value of myocardial work parameters derived from PSL for evaluating cardiac function and clinical prognosis in patients with pulmonary hypertension (PH).

Methods

A total of 52 patients with PH and 27 healthy controls were enrolled in this prospective study. PSLs determined by echocardiography were used to calculate global work index (GWI) of left ventricle (LV) and right ventricle (RV). Global constructive work (GCW) comprised the sum of myocardial work performed during shortening in systole and during lengthening in isovolumic relaxation. Global wasted work (GWW) comprised the sum of myocardial work performed during lengthening in systole and during shortening in isovolumic relaxation. Global work efficiency (GWE) was defined as GCW/(GCW + GWW).

Results

LVGWW, RVGWI, RVGCW and RVGWW were significantly higher in patients than controls (all P < 0.001). LVGWE, LVGWI, LVGCW, and RVGWE were lower in patients than controls (all P < 0.01). Myocardial work parameters correlated well with clinical and other conventional echocardiographic assessments (all P < 0.05). In binary logistic regression analysis, the combination of RVGWE and estimation of pulmonary arterial systolic pressure (ePASP) was the best model to predict clinical outcomes (OR = 0.803, P = 0.002 and OR = 1.052, P = 0.015, respectively). Receiver operating characteristic curv demonstrated the combination of RVGWE and ePASP was the best predictor of adverse events with 100% sensitivity and 76.3% specificity (AUC = 0.910, P < 0.001).

Conclusion

Myocardial work parameters derived from PSL are emerging markers of cardiac function. And the combination of RVGWE and ePASP is a useful predictor of clinical outcome in PH patients.

State of the art: multimodality imaging in dilated cardiomyopathy

Dilated cardiomyopathy represents a common phenotype expressed in individuals with a family of overlapping myocardial diseases due to acquired and/or genetic susceptibility. Disease trajectory, response to therapy and outcomes vary widely; therefore, further refinement of the diagnosis can help guide therapy and inform prognosis. Multimodality imaging plays a key role in this process, as well as excluding alternative causes which may mimic a primary myocardial disease. The following article discusses the role of different imaging modalities as well as what the future may look like in the context of recent research innovations.

Deterioration in myocardial work indices precedes changes in global longitudinal strain following anthracycline chemotherapy

BACKGROUND

Left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS) have conventionally been used for surveillance of cardiac function after cancer therapy, but indices of myocardial work (MW) are potentially superior for this purpose because they take into account both myocardial deformation and loading conditions.

OBJECTIVES

We aimed to investigate the usefulness of MW in the follow-up of children and young adults following anthracycline chemotherapy.

METHODS

Conventional markers of LV function (LV fractional shortening [LVFS], LVEF, GLS) and MW indices (global work index [GWI], global constructive work [GCW], global wasted work [GWW], and global work efficiency [GWE]) were obtained from 2342 echocardiographic examinations in 598 patients (354 male, 12.2 [4.7-17.3] years at initiation of chemotherapy).

RESULTS

GWI, GCW, GLS, LVFS, and LVEF all deteriorated significantly during and after anthracycline chemotherapy, while GWW decreased and GWE was preserved. On multivariable analysis, MW indices were correlated with conventional markers of LV function and with clinical information relating to underlying malignancy and chemotherapy. Cox regression analysis revealed that similar levels of deterioration in GWW, GWI, and GCW preceded those in GLS, LFS, and LVEF.

CONCLUSIONS

Non-invasive MW indices correlate well with conventional markers of LV function. Indices of MW appear to provide an earlier and more sensitive marker of progression towards chemotherapy-related cardiac dysfunction. Future studies are warranted to validate whether the incorporation of non-invasive MW into the routine clinical surveillance in patients after chemotherapy would improve outcomes.

Myocardial work: the analytical methodology and clinical utilities

The evaluation of left ventricular (LV) systolic function is an essential part of the clinical practice of cardiology. Although left ventricular ejection fraction (LVEF) is the most validated and widely used parameter, it has fundamental limitations. LV strain is more sensitive to detect subtle myocardial dysfunction when LVEF was preserved, but it is load-dependent. Invasive left ventricular pressure-volume loop (LV-PVL) is the reliable standard to evaluate cardiac function, but its wide clinical application is limited by the risk of invasive LV pressure detection. Until the advent of non-invasive LV pressure-strain loop (LV-PSL), things have changed. LV-PSL is in good agreement with regional myocardial oxygen consumption and metabolism. Compared with traditional echocardiographic parameters or LV strain, myocardial work (MW) derived from LV-PSL is a more advanced tool that combines deformation as well as hemodynamics through integration of global longitudinal strain and non-invasive LV systolic pressure. In recent years, researches on MW are going on in full swing and show many advantages of MW. This review described the method and discussed the applications, advantages, limitations, and prospects of MW in multiple cardiovascular diseases. The goal is to provide the readers new insights for evaluating LV systolic function and promote the incorporation of MW into daily practice.

Evolution of non-invasive myocardial work in tako-tsubo cardiomyopathy

Tako-tsubo cardiomyopathy (TTC) is characterized by left ventricular (LV) systolic dysfunction with transient wall motion abnormalities (WMA). However, whether systolic performance fully recovers is unclear. Non-invasive myocardial work (MW) is a new tool to assess the LV performance, never described in this setting. To assess MW in apical TTC. Fifty patients with the apical variant TTC (77 ± 10 years, 47 women) were enrolled and underwent a transthoracic echocardiography within 24 h of admission and a median of 36 days at follow-up (FU). Constructive work (CW), wasted work (WW), MW index (MWI) and efficiency (MWE) were derived from a strain- pressure loop obtained from non-invasive brachial blood pressure and 2D strain. Hospital complications (HC) were defined as heart failure, LV apical thrombus, and ventricular arrhythmia. A control group of 24 matched-subjects was used. Myocardial work improved significantly between the acute phase and follow-up (global, and all apical and middle segments for all indices, all, p < 0.01; and some basal segments for MWI and CW, all p < 0.05). The degree of impairment of MW followed an apical-basal gradient (worse in apical segments), which inverted at follow-up. Furthermore, in TTC, global CW and MWI were significantly impaired in patients with HC (n = 10, all p < 0.05). At follow-up, global and regional MW remained significantly reduced by comparison to the control group (CW, MWI, MWE, WW, all p < 0.01), despite similar hemodynamics, LVEF and 2D-strain (all, p = NS). Myocardial work is transiently altered in apical TTC and significantly associated to HC. Despite total recovery of WMA, subtle dysfunction of myocardial performance persists at FU.

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.

Relation of Myocardial Work Indexes and Forward Flow Reserve in Patients With Significant Secondary Mitral Regurgitation Undergoing Transcatheter Mitral Valve Repair

Left ventricular (LV) myocardial work (LVMW) indexes have shown incremental value over LV ejection fraction and were found to have prognostic significance in patients with secondary mitral regurgitation. We therefore aimed to investigate the association between LVMW indexes and forward flow reserve in patients with secondary mitral regurgitation, treated with transcatheter edge-to-edge repair (TEER). LVMW indexes were evaluated at baseline and forward stroke volume index (FSVI) was evaluated at baseline and 6-month follow-up after TEER. Patients were divided in 2 groups: improvers (improvement in FSVI ≥20%) and nonimprovers (improvement in FSVI <20%). A total of 70 patients (median age 76 years, 59% men) were included. FSVI was the only echocardiographic parameter that improved after TEER. There was a significant decrease in LV global longitudinal strain in the nonimprovers (p = 0.002) but not in the improvers (p = 0.177). Global work index and global constructive work worsened in nonimprovers (p = 0.005 and p = 0.004, respectively), whereas no difference was seen in these indexes in improvers (p = 0.093 and p = 0.112, respectively). Global work efficiency remained independently associated with forward flow reserve after adjusting for a variety of potential confounders. In conclusion, FSVI nonimprovers demonstrated worsening of LV systolic function after TEER compared with improvers, in whom LV systolic function remained stable. Global work efficiency was associated with FSVI improvement after TEER, independent of LV systolic function.

The Role of Cardiac Imaging in Heart Failure with Reduced Ejection Fraction

Heart failure (HF) is a major health burden associated with significant morbidity and mortality. Approximately half of all HF patients have reduced ejection fraction (left ventricular ejection fraction <40%) at rest (HF with reduced ejection fraction). The aetiology of HF is complex, and encompasses a wide range of cardiac conditions, hereditary defects and systemic diseases. Early identification of aetiology is important to allow personalised treatment and prognostication. Cardiac imaging has a major role in the assessment of patients with HF with reduced ejection fraction, and typically incorporates multiple imaging modalities, each with unique but complimentary roles. In this review, the comprehensive role of cardiac imaging in the diagnosis, assessment of aetiology, treatment planning and prognostication of HF with reduced ejection fraction is discussed.

Myocardial Work Brings New Insights into Left Ventricular Remodelling in Cardio-Oncology Patients

Serial transthoracic echocardiographic (TTE) assessment of 2D left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS) are the gold standard screening methods for cancer therapeutics-related cardiac dysfunction (CTRCD). Non-invasive left ventricular (LV) pressure-strain loop (PSL) provides a novel method of quantifying myocardial work (MW) with potential advantages to evaluate the impact of cardiotoxic treatments on heart function. We prospectively assessed breast cancer female patients undergoing cancer therapy through serial monitoring by 2D and 3D TTE. Patients were evaluated at T0, T1 and T2 (before, 4–6 and 12–14 months after starting therapy, respectively). Through PSL analysis, MW indices were calculated. A total of 122 patients, with a mean age of 54.7 years, who received treatment with anthracyclines (77.0%) and anti-HER2 (75.4%) were included. During a mean follow-up of 14.9 ± 9.3 months, LVEF and GLS were significantly diminished, and 29.5% developed CTRCD. All MW indices were significantly reduced at T1 compared with baseline and tended to return to baseline values at T2. Global work index and global work efficiency showed a more pronounced variation in patients with CTRCD. The presence of more than one cardiovascular risk factor, obesity and baseline left atrium volume were predictors of changes in MW parameters. In conclusion, breast cancer treatment was associated with LV systolic dysfunction as assessed by MW, with its peak at 4–6 months and a partial recovery afterwards. Assessment of myocardial deformation parameters allows a more detailed characterization of cardiac remodelling and could enhance patient screening and selection for cardioprotective therapeutics.

Strain Imaging for the Early Detection of Cardiac Remodeling and Dysfunction in Primary Aldosteronism

Speckle tracking echocardiography is a novel technique to quantify cardiac function and deformation. It has been applied in a series of cardiovascular diseases for the evaluation of early cardiac impairment. We recently used this technique to investigate cardiac structure and function in patients with primary aldosteronism. Cardiac damage usually occurs earlier in patients with primary aldosteronism than those with primary hypertension, probably because aldosterone hypersecretion is more commonly observed in the former than the latter patients. In this article, we will review the imaging studies, especially with speckle tracking echocardiography, for the detection of early cardiac dysfunction in primary aldosteronism as a disease model.

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.

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.

Usefulness of Noninvasive Myocardial Work to Predict Left Ventricular Recovery and Acute Complications after Acute Anterior Myocardial Infarction Treated by Percutaneous Coronary Intervention

BACKGROUND

Predicting left ventricular recovery (LVR) after acute ST-elevation myocardial infarction (STEMI) is challenging and of prognostic importance. Our objective was to evaluate the usefulness of noninvasive myocardial work (MW), a new index of global and regional myocardial performance, to predict LVR and in-hospital complications after STEMI.

METHODS

Ninety-three patients with anterior STEMI (mean age, 59 ± 12 years) treated by percutaneous coronary intervention (PCI) were prospectively enrolled and underwent a transthoracic Doppler echocardiography within 24-48 hours after PCI and a median of 92 days at follow-up. Myocardial work is derived from the strain-pressure relation, integrating in its calculation the noninvasive arterial pressure. Segmental LVR was defined as a normalization of wall motion abnormalities of the affected segments and global recovery as an absolute improvement of left ventricular ejection fraction (LVEF) > 5% in patients with baseline LVEF ≤ 50%. In-hospital complications were defined as a composite of death, reinfarction, heart failure, and LV apical thrombus.

RESULTS

Segmental MW was impaired in infarct segments, more severely in nonrecovering versus recovering segments (P < .01). Furthermore, global constructive MW was significantly correlated with follow-up LVEF (r = 0.58) and global longitudinal strain (r = -0.67; all P < .01). Constructive MW was the best index to predict segmental (P < .01 vs MW index, MW efficiency, and wasted work) and global recovery (P < .05 vs global longitudinal strain) with an independent association (odds ratio = 1.17, 95% CI, 1.13-1.20, and odds ratio = 1.43, 95% CI, 1.18-1.68, respectively; all P < .001). Moreover, global constructive MW was more severely impaired in patients with in-hospital complications (n = 16; P < .01).

CONCLUSIONS

In patients with anterior STEMI treated by PCI, constructive MW is an independent predictor of segmental and global LVR and is significantly impaired in patients with in-hospital complications.

Prognostic Implications of Left Ventricular Myocardial Work Indices in Patients With Secondary Mitral Regurgitation

BACKGROUND

Assessment of left ventricular (LV) function in patients with secondary mitral regurgitation (SMR) remains challenging but is an important parameter for risk stratification. The association of LV myocardial work components (work index [GWI], constructive [GCW] and wasted [GWW] work, and work efficiency) derived from pressure-strain loops obtained with speckle tracking echocardiography, and all-cause mortality in patients with SMR was investigated.

METHODS

LV myocardial GWI, GCW, GWW, and global work efficiency were measured with speckle tracking strain echocardiography in 373 patients (72% men, median age 68 years) with various grades of SMR. All-cause mortality was the primary end point.

RESULTS

Mild SMR was observed in 143 patients, 128 had moderate SMR, and 102 had severe SMR. Patients with severe SMR had the largest LV volumes and the worst LV ejection fraction and LV global longitudinal strain. In patients with severe SMR, LV GWI and GCW were more impaired (500 mm Hg% versus 680 mm Hg% P=0.024 and 678 mm Hg% versus 851 mm Hg% P=0.006, respectively), while GWW was lower (130 mm Hg% versus 260 mm Hg% P<0.001, respectively) and global work efficiency was significantly higher (82% versus 76%, P=0.001) compared with patients with mild SMR. After a median follow-up of 56 months, 161 patients died. LV GWI≤500 mm Hg%, LV GCW≤750 mm Hg%, and LV GWW<300 mm Hg% were independently associated with excess mortality.

CONCLUSIONS

Patients with severe SMR had the worst LV GWI and LV GCW but better LV GWW and global work efficiency reflecting the unloading of the LV in the low-pressure left atrial chamber. These parameters were independently associated with worse long-term survival in patients with SMR.

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.

Clinical Significance of Global Wasted Work in Patients with Heart Failure Receiving Cardiac Resynchronization Therapy

BACKGROUND

The relationship between myocardial work assessment using pressure-strain loops by echocardiography before cardiac resynchronization therapy (CRT) and response to CRT has been recently revealed. Among myocardial work parameters, the impact of left ventricular myocardial global wasted work (GWW) on response to CRT and outcome following CRT has been seldom studied. Hence, the authors evaluated the relationship between preprocedural GWW and outcome in a large prospective cohort of patients with heart failure (HF) and reduced ejection fraction receiving CRT.

METHODS

The study included 249 patients with HF. Myocardial work indices including GWW were calculated using speckle-tracking strain two-dimensional echocardiography using pressure-strain loops. End points of the study were (1) response to CRT, defined as left ventricular reverse remodeling and/or absence of hospitalization for HF, and (2) all-cause death during follow-up.

RESULTS

Median follow-up duration was 48 months (interquartile range, 43-54 months). Median preoperative GWW was 281 mm Hg% (interquartile range, 184-388 mm Hg%). Preoperative GWW was associated with CRT response (area under the curve, 0.74; P < .0001), and a 200 mm Hg% threshold discriminated CRT nonresponders from responders with 85% specificity and 50% sensitivity, even after adjustment for known predictors of CRT response (adjusted odds ratio, 4.03; 95% CI, 1.91-8.68; P < .001). After adjustment for established predictors of outcome in patients with HF with reduced ejection fraction receiving CRT, GWW < 200 mm Hg% remained associated with a relative increased risk for all-cause death compared with GWW ≥ 200 mm Hg% (adjusted hazard ratio, 2.0; 95% CI, 1.1-3.9; P = .0245). Adding GWW to a baseline model including known predictors of outcome in CRT resulted in an improvement of this model (χ² to improve 4.85, P = .028). The relationship between GWW and CRT response and outcome was stronger in terms of size effect and statistical significance than for other myocardial work indices.

CONCLUSIONS

Low preoperative GWW (<200 mm Hg%) is associated with absence of CRT response in CRT candidates and with a relative increased risk for all-cause death. GWW appears to be a promising parameter to improve selection for CRT of patients with HF with reduced ejection fraction.

Current Role of Echocardiography in Cardiac Resynchronization Therapy: from Cardiac Mechanics to Flow Dynamics Analysis

PURPOSE OF REVIEW

The aim of this review is to summarily explain what LV synchrony, coordination, myocardial work, and flow dynamics are, trying to clarify their advantages and limitations in the treatment of heart failure patients undergoing or with implanted cardiac resynchronization therapy (CRT).

RECENT FINDINGS

CRT is an established treatment for patients with heart failure and left ventricular systolic dysfunction. In the current guidelines, CRT implant indications rely only on electrical dyssynchrony, but in the last years, many aspects of cardiac mechanics (including contractile synchrony, coordination, propagation, and myocardial work) and flow dynamics have been studied using echocardiographic techniques to better characterize patients undergoing or with implanted CRT. However, the concepts, limits, and potential applications of all these echocardiographic evaluations are unclear to most clinicians. The use of left ventricular dyssynchrony and discoordination indices may help to identify those significant mechanical alterations whose correction may increase the probability of a favorable CRT response. Assessment of myocardial work and intracardiac flow dynamics may overcome some limitations of the conventional evaluation of cardiac mechanics but more investigations are needed before extensive clinical application.

Assessing left ventricular systolic function: from ejection fraction to strain analysis

The measurement of left ventricular ejection fraction (LVEF) is a ubiquitous component of imaging studies used to evaluate patients with cardiac conditions and acts as an arbiter for many management decisions. This follows early trials investigating heart failure therapies which used a binary LVEF cut-off to select patients with the worst prognosis, who may gain the most benefit. Forty years on, the cardiac disease landscape has changed. Left ventricular ejection fraction is now a poor indicator of prognosis for many heart failure patients; specifically, for the half of patients with heart failure and truly preserved ejection fraction (HF-PEF). It is also recognized that LVEF may remain normal amongst patients with valvular heart disease who have significant myocardial dysfunction. This emphasizes the importance of the interaction between LVEF and left ventricular geometry. Guidelines based on LVEF may therefore miss a proportion of patients who would benefit from early intervention to prevent further myocardial decompensation and future adverse outcomes. The assessment of myocardial strain, or intrinsic deformation, holds promise to improve these issues. The measurement of global longitudinal strain (GLS) has consistently been shown to improve the risk stratification of patients with heart failure and identify patients with valvular heart disease who have myocardial decompensation despite preserved LVEF and an increased risk of adverse outcomes. To complete the integration of GLS into routine clinical practice, further studies are required to confirm that such approaches improve therapy selection and accordingly, the outcome for patients.

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.

Prognostic implications of left ventricular myocardial work index in patients with ST-segment elevation myocardial infarction and reduced left ventricular ejection fraction

AIMS

This study aimed to determine whether lower values of left ventricular (LV) global work index (GWI) at baseline were associated with a reduction in LV functional recovery and poorer long-term prognosis in patients with reduced LV ejection fraction (LVEF ≤40%) following ST-segment elevation myocardial infarction (STEMI).

METHODS AND RESULTS

A total of 197 individuals (62 ± 12 years, 75% male) with STEMI treated with primary percutaneous coronary intervention and reduced LVEF were evaluated. All patients were followed up for the occurrence of all-cause mortality and the presence of LVEF normalization at 6 months (LVEF ≥50%). The median LVEF was 36% (interquartile range 32-38) and the mean value of LV GWI was 1041 ± 404 mmHg% at baseline. At 6-month follow-up, 41% of patients had normalized LVEF. On multivariable logistic regression, higher values of LV GWI were independently associated with LVEF normalization at 6 months of follow-up (odds ratio 1.32 per 250 mmHg%, P = 0.038). Over a median follow-up of 112 months, 40 patients (20%) died. LV GWI <750 mmHg% was independently associated with all-cause mortality (HR 3.85, P < 0.001) and was incremental to LV global longitudinal strain (P = 0.039) and LVEF (P < 0.001).

CONCLUSION

In individuals with an LVEF ≤40% following STEMI, higher values of LV GWI were associated with a greater probability of LVEF normalization at 6-month follow-up. In addition, lower values of LV GWI were independently associated with increased all-cause mortality at long-term follow-up, providing incremental prognostic value over LVEF and minor incremental prognostic value over LV global longitudinal strain.

The Utility of Myocardial Work in Clinical Practice

Myocardial work (MW) is a novel technique used in the advanced assessment of left ventricular function. In the past few years, this invasive measure has evolved to become a more attainable noninvasive technique. MW has benefits over left ventricular ejection fraction and global longitudinal strain by speckle-tracking echocardiography, as it includes the afterload-dependent limitation and dynamic myocardial contraction in relationship to various loading conditions. In this article, the authors provide a summary overview and discuss the additive value noninvasive MW provides to left ventricular systolic function assessment. The authors explore the evolution of invasive to noninvasive MW, examine how to acquire and measure, discuss normal reference values, examine its role in a multitude of cardiac conditions that have been investigated in current research, review a variety of clinical applications, and discuss potential limitations. The goal is to allow the reader to see the benefits of this rapidly emerging application and be able to incorporate it into everyday practice.

The value of non-invasive myocardial work indices derived from left ventricular pressure-strain loops in predicting the response to cardiac resynchronization therapy

Background

Non-invasive left ventricular (LV) pressure-strain loops (PSLs), which are generated by combining LV longitudinal strain with brachial artery blood pressure, provide a novel method of quantifying global and segmental myocardial work (MW) indices with potential advantages over conventional echocardiographic strain data, which suffers from being load-dependent. This method has been recently introduced in echocardiographic software, enhancing the efficiency of MW calculations. This study aimed to evaluate the role of non-invasive MW indices derived from LV PSLs in predicting cardiac resynchronization therapy (CRT) response.

Methods

A total of 106 heart failure (HF) patients scheduled for CRT were included in the MW analysis. Global and segmental (septal and lateral at the mid-ventricular level) MW indices were assessed before CRT and at a 6-month follow-up. Response to CRT was defined as ≥15% reduction in LV end-systolic volume and ≥1 NYHA functional class improvement at 6-month follow-up compared to baseline.

Results

CRT response was observed in 78 (74%) patients. At baseline, the global work index (GWI) and global constructive work (GCW) were significantly higher in CRT responders than in non-responders (both P<0.05). Furthermore, responders exhibited significantly higher mid lateral MW and mid lateral constructive work (CW) (both P<0.001), but significantly lower mid septal MWI and mid septal myocardial work efficiency (MWE) than non-responders (all P<0.01). Baseline mid septal MWE (OR 0.975, 95% CI: 0.959-0.990, P=0.002) and mid lateral MWI (OR 1.003, 95% CI: 1.002-1.004, P<0.001) were identified as independent predictors of CRT response in multivariate regression analysis. Mid septal MWE ≤42% combined with mid lateral MWI ≥740 mmHg% predicted CRT response, with an optimal sensitivity of 79% and specificity of 82% [area under the receiver operating characteristic curve (AUC) =0.830, P<0.001].

Conclusions

Assessment of MW indices before CRT could identify the marked imbalance in LV MW distribution and can be widely used as a reliable complementary tool for guiding patient selection for CRT in clinical practice.

Global Left Ventricular Myocardial Work Efficiency and Long-Term Prognosis in Patients After ST-Segment-Elevation Myocardial Infarction

BACKGROUND

Left ventricular (LV) global longitudinal strain has demonstrated incremental prognostic value over LV ejection fraction in patients with ST-segment-elevation myocardial infarction. However, LV global longitudinal strain does not take into consideration the effect of afterload. Novel speckle-tracking echocardiographic indices of myocardial work integrate blood pressure measurements (afterload) with LV global longitudinal strain. The present study aimed to investigate the prognostic value of global LV myocardial work efficiency (GLVMWE; reflecting LV performance) obtained from pressure-strain loops with echocardiography in patients with ST-segment-elevation myocardial infarction.

METHODS

A total of 507 ST-segment-elevation myocardial infarction patients (mean age, 61±11 years; 76% men) were retrospectively analyzed. LV ejection fraction and GLVMWE were measured by transthoracic echocardiography within 48 hours of admission. GLVMWE was defined as the ratio of constructive work divided by the sum of constructive and wasted work in all LV segments and expressed as a percentage. Spline curve analysis was used to define the association between reduced GLVMWE and all-cause death.

RESULTS

After a median follow-up of 80 months (interquartile range, 67-97 months), 40 (8%) patients died. Patients with reduced GLVMWE (<86%) showed higher cumulative rates of all-cause mortality (17.5% versus 4.7%; log-rank P<0.001) in comparison with patients with preserved GLVMWE (≥86%). Reduced GLVMWE (<86%) showed an independent association with all-cause mortality (hazard ratio, 3.167 [95% CI, 1.679-5.972]; P<0.001).

CONCLUSIONS

Reduced GLVMWE (<86%) measured by transthoracic echocardiography within 48 hours of admission in ST-segment-elevation myocardial infarction patients is associated with worse long-term survival.

A Prospective Comparative Study on Cardiac Alterations After Surgery and Drug Treatment of Primary Aldosteronism

BACKGROUND

Current guideline recommends both surgery and drug treatment for primary aldosteronism. Treatment effects on the cardiac structure and function remain under investigation.

OBJECTIVE

We performed a prospective study in patients with primary aldosteronism to compare effects of surgery and drug treatment on the cardiac structure and function as assessed by the left ventricular (LV) pressure-strain loop, a novel echocardiographic technique that incorporates myocardial deformation and LV pressure.

METHODS

Our study included 39 and 28 patients treated with surgery and a mineralocorticoid antagonist, respectively. We performed conventional and speckle tracking echocardiography at baseline and 3 and 6 months of follow-up.

RESULTS

During follow-up, both surgery and drug treatment normalized serum potassium concentration and significantly reduced blood pressure. Both treatments significantly and similarly decreased LV mass index and left atrial volume index. However, only in the surgery group did global wasted work significantly decrease (200.8 ± 86.7 at baseline vs. 142.1 ± 58.1 mmHg% at 6 months) and global work efficiency (91.5 ± 3.1 vs. 93.6 ± 2.3%) and global longitudinal strain (-18.3 ± 2.7 vs. -19.2 ± 1.9%) significantly (p < 0.01) increase at 6 months of follow-up. The corresponding differences from the changes in the drug treatment group were 39.5 mmHg% (95% CI, 17.1, 62.0 mmHg%), -1.64% (95% CI, -2.56, -0.71%), and -0.85% (95% CI, -1.51, -0.20%), respectively. In addition, the changes in global wasted work at 6 months of follow-up was significantly correlated with that in 24-h urinary aldosterone excretion in the drug treatment group (r = 0.54) and two groups combined (r = 0.55), but not the surgery group.

CONCLUSION

In spite of similar serum potassium normalization and blood pressure control, surgical removal of an adrenal gland, but not mineralocorticoid receptor antagonism, showed early improvement in cardiac function.

The year 2019 in the European Heart Journal-Cardiovascular Imaging: Part I

The European Heart Journal-Cardiovascular Imaging was launched in 2012 and has during these years become one of the leading multimodality cardiovascular imaging journals. The journal is now established as one of the top cardiovascular journals and is the most important cardiovascular imaging journal in Europe. The most important studies published in our Journal in 2019 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.

Left Ventricular Pressure-Strain Loop-Based Quantitative Examination of the Global and Regional Myocardial Work of Patients with Dilated Cardiomyopathy

The aim of our prospective pilot study was to explore the distribution characteristics of myocardial work (MW) of patients with dilated cardiomyopathy (DCM) and their clinical value in evaluation of therapeutic effects. Thirty patients with DCM were enrolled in the case group, and 30 healthy patients were randomly allocated to the control group. Global myocardial work (GMW) and regional myocardial work (RMW) of the control and case groups before and after therapy were evaluated by using left ventricular pressure-strain loops and then compared. We found significant differences in GMW and RMW between the control and case groups (p < 0.05). Compared with before therapy, the global work index and 6-min walking distance increased, but LV ejection fraction and global longitudinal strain did not significantly change after therapy. GMW was significantly correlated with LV ejection fraction and global longitudinal strain (p < 0.01). Bland-Altman plot analysis revealed that GMW values were consistent between and within the groups. The results suggest that LV MW values were diffusely impaired in patients with DCM and that the global work index may be used as an indicator in evaluation of therapeutic effects.

Myocardial Work in Nonobstructive Hypertrophic Cardiomyopathy: Implications for Outcome

BACKGROUND

Noninvasive left ventricular (LV) pressure-strain loop analysis is emerging as a new echocardiographic method to evaluate LV function, integrating longitudinal strain by speckle-tracking analysis and sphygmomanometrically measured blood pressure to estimate myocardial work. The aims of this study were (1) to describe global and segmental myocardial work in patients with hypertrophic cardiomyopathy (HCM), (2) to assess the correlation between myocardial work and other echocardiographic parameters, and (3) to evaluate the association of myocardial work with adverse outcomes.

METHODS

One hundred ten patients with nonobstructive HCM (mean age, 55 ± 15 years; 66% men), with different phenotypes (apical, concentric, and septal hypertrophy), and 35 age- and sex-matched healthy control subjects were included. The following myocardial work indices were included: myocardial work index, constructive work (CW), wasted work, and cardiac efficiency. The combined end point included all-cause mortality, heart transplantation, heart failure hospitalization, aborted sudden cardiac death, and appropriate implantable cardioverter-defibrillator therapy.

RESULTS

Mean global CW (1,722 ± 602 vs 2,274 ± 574 mm Hg%, P < .001), global cardiac efficiency (93% [89%-95%] vs 96% [96%-97%], P < .001), and global MWI (1,534 ± 551 vs 1,929 ± 473 mm Hg%) were significantly reduced, while global wasted work (104 mm Hg% [66-137 mm Hg%] vs 71 mm Hg% [49-92 mm Hg%], P < .001) was increased in patients with HCM compared with control subjects. Segmental impairment in CW colocalized with maximal wall thickness (HCM phenotype), and global CW correlated with LV wall thickness (r = -0.41, P < .001), diastolic function (r = -0.27, P = .001), and QRS duration (r = -0.28, P = .001). Patients with global CW > 1,730 mm Hg% (the median value) experienced better event-free survival than those with global CW < 1,730 mm Hg% (P < .001).

CONCLUSIONS

Myocardial work, assessed noninvasively using echocardiography and blood pressure measurement, is reduced in patients with nonobstructive HCM; it correlates with maximum LV wall thickness and is significantly associated with a worse long-term outcome.

[Myocardial work in assessment of left ventricular systolic function]

This review focuses on a new method for noninvasive, complex evaluation of left ventricular (LV) systolic function using an echocardiography-based technology of computing indexes of myocardial performance by construction of pressure-deformation curves. Since this new method accounts for the effect of afterload on myocardial contractility, the article presents data demonstrating advantages of the evaluation of LV myocardial performance over the speckle-tracking echocardiography and other methods in diagnostics of several diseases. The review provides a description of this method and its advantages and limitations. The authors analyzed results of major studies on evaluation of LV performance. Prospects of implementation and practical use of the method are discussed in the aspects of diagnostics of cardiovascular diseases and risk stratification for different groups of patients.