Non-Doppler two-dimensional strain imaging by echocardiography--from technical considerations to clinical applications

Two-dimensional speckle tracking imaging analyses of the correlations between left atrial appendage function and stroke risk in nonvalvular atrial fibrillation patients

Stroke incidence is the most severe complication associated with atrial fibrillation (AF), and the most common site of thrombus formation in AF patients is the left atrial appendage (LAA). This study was developed to use two-dimensional speckle tracking imaging (2D-STI) to explore associations between LAA strain/strain rate and stroke incidence and to evaluate the value of utilizing LAA strain and strain rate values to support the stratification of nonvalvular AF (NVAF) patients based on stroke risk. A total of 486 AF patients who had undergone transesophageal echocardiography to exclude potential intracardiac thrombosis between March 2021 and November 2022 were consecutively enrolled. Patients meeting the inclusion criteria were separated into two groups according to their history of stroke/transient ischemic attack (TIA). LAA strain and strain rate values in these patients were measured via 2D-STI. Multivariable logistic regression analysis was employed to determine independent risk factors for the construction of a combined predictive model. Of the 333 analyzed patients (134 females, aged 65 (56,72) years), 39 (11.71%, 39/333) had a history of stroke at the time of evaluation. Multivariate logistic regression analysis demonstrated that nonparoxysmal AF, CHA2DS2VASc score, LAA thrombus/spontaneous echo contrast (SEC), LAA strain, and strain rate were all predictors of stroke incidence among NVAF patients. The combined predictive model demonstrated excellent discriminative ability, with an AUC of 0.91 (95%CI 0.87-0.95, P < 0.001), and a sensitivity and specificity of 79.49% and 89.46%, respectively. The Hosmer-Lemeshow test confirmed good calibration, yielding a value of 0.98. Comparative decision curve analysis showed that the model provided superior net benefits compared to the CHA2DS2VASc score. Furthermore, the model exhibited improved predictive performance and reclassification for stroke when compared to the CHA2DS2VASc score (AUC 0.91 vs. 0.88, Z = 2.32, P = 0.02), accompanied by a significant increase in the net reclassification index (+ 5.44%, P < 0.001) and integrated discrimination improvement (8.21%, P < 0.001). These data demonstrate that LAA strain and strain rate, as measured via 2D-STI, can offer value when assessing LAA function in AF patients, potentially providing further predictive value to extant clinical risk scoring strategies.

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.

Myocardial dysfunction assessed by speckle-tracking in good-grade subarachnoid hemorrhage patients (WFNS 1-2): a prospective observational study

BACKGROUND

Cardiac complications due to non-traumatic subarachnoid hemorrhage (SAH) are usually described using classical echocardiographic evaluation. Strain imaging appears to have better sensitivity than standard echocardiographic markers for the diagnosis of left ventricular dysfunction. The aim of this study was to determine the prevalence of cardiac dysfunction defined as a Global Longitudinal Strain (GLS) ≥  - 20% in patients with good-grade SAH (WFNS 1 or 2).

METHODS

Seventy-six patients with good-grade SAH were prospectively enrolled and analyzed at admission for neurocritical care. Transthoracic echocardiography was performed on days 1, 3, and 7 after hemorrhage. Routine measurements, including left ventricular ejection fraction (LVEF), were performed, and off-line analysis was performed by a blinded examiner, to determine 2-, 3-, and 4-cavity longitudinal strain and left ventricular GLS. GLS was considered altered if it was ≥  - 20%, we also interested the value of ≥  - 17%. LVEF was considered altered if it was < 50%.

RESULTS

On day 1, 60.6% of patients had GLS ≥  - 20% and 21.2% of patient had GLS ≥  - 17%. In comparison, alteration of LVEF was present in only 1.7% of patients. The concordance rate between LVEF < 50% and GLS ≥  - 20% and LVEF ≥ 50% and GLS <  - 20% was 46%.

CONCLUSION

Strain imaging showed a higher prevalence (60.6%) of left ventricular dysfunction during the acute phase of good-grade SAH (WFNS 1 or 2) than previously described.

Comparative effects of nebivolol and carvedilol on left ventricular diastolic function in older patients with heart failure and preserved ejection fraction

Background

Although many studies have compared carvedilol and nebivolol in heart failure (HF) patients with reduced left ventricular ejection fraction (LVEF), such comparative studies for the elderly have not been reported yet. Nebivolol is known to be effective for improving diastolic function of elderly patients with HF. Thus, this study aimed to determine whether nebivolol could improve LV diastolic function to a greater extent than carvedilol in older patients aged over 70 years.

Methods

This trial was a prospective, randomized, open-label, single-center, active-controlled study that enrolled 62 patients with class II or III HF over 70 years of age with an LVEF ≥40%. Patients were randomized into a carvedilol group or a nebivolol group. Transthoracic echocardiography was performed at baseline and 12 months by the same investigator who was blinded to clinical data. The primary endpoint was E/e' measured by echocardiographic evaluation 12 months after treatment.

Results

The median duration of follow-up was 24 months. Baseline clinical characteristics and echocardiographic parameters, such as LV diastolic function indices, did not differ significantly between carvedilol and nebivolol groups. Twelve-month follow-up echocardiography data showed no significant difference in E/e' or other LV diastolic function indices between the two groups. There were no significant changes in echocardiographic parameters over 12 months in either group.

Conclusions

There was no difference between carvedilol and nebivolol for improving diastolic function of elderly HF patients with LVEF ≥40%. This study showed no superiority of nebivolol over carvedilol in elderly patients with HF.

Two-dimensional speckle tracking-derived global longitudinal strain in healthy Doberman Pinschers: method evaluation, variability, and reference values

INTRODUCTION

Evaluation of two-dimensional speckle tracking (2D-ST)-derived global longitudinal strain (GLS) in healthy Doberman Pinschers (DP) is essential before it can be used in diseased DP to assess systolic function. To determine feasibility and observer related measurement variability of 2D-ST-derived GLS by use of AutoSTRAIN (AUTO) and 2D Cardiac Performance Analysis (TomTec Imaging Systems GmbH, Unterschleissheim, Germany).

ANIMALS, MATERIALS, AND METHODS

This prospective study included 120 healthy, client-owned DP presented for screening evaluation. Global longitudinal strain of the apical four- (GLS_A4C), two-, and three-chamber view as well as the average GLS of all three views combined (GLS_AV) were determined, compared, and reference values established. Measurement variability was assessed by using intra- and inter-observer coefficient of variation.

RESULTS

A small difference existed for GLS_AV (mean + 0.23%; P=0.022) between the two software programs although the determined strain values were similar and positively correlated (r = 0.84; P<0.001). No difference could be found between GLS_AV and GLS_A4C for AUTO (mean + 0.16%; P=0.228), whereas a difference existed for Cardiac Performance Analysis (mean -0.89% (end-systolic strain) and -0.56% (peak strain), P<0.0001). Software specific reference values were established for GLS_AV and GLS_A4C. Intra- and inter-observer coefficient of variation revealed very low to low measurement variability, with better results for AUTO.

DISCUSSION AND CONCLUSIONS

Two-dimensional speckle tracking (2D-ST) derived GLS is a feasible technique to assess systolic function with low measurement variability. Whenever possible, GLS_AV should be determined, although GLS_A4C might be a potential alternative.

Circumferential Strain as a Marker of Vessel Reactivity in Patients with Intradialytic Hypotension

Background and Objectives: Intradialytic hypotension (IDH) complicates 4 to 39.9% of hemodialysis (HD) sessions. Vessels' reactivity disturbances may be responsible for this complication. Two-dimensional speckle tracking is used to assess arterial circumferential strain (CS) as a marker of the effectiveness of the cardiovascular response to the reduction of circulating plasma. Materials and Methods: The common carotid artery (CCA) and common iliac artery (CIA) CSs were recorded using ultrasonography in 68 chronically dialyzed patients before and after one HD session. Results: In patients with IDH episodes (n = 26), the CCA-CS was significantly lower both before (6.28 ± 2.34 vs. 4.63 ± 1.74 p = 0.003) and after HD (5.00 (3.53-6.78) vs. 3.79 ± 1.47 p = 0.010) than it was in patients without this complication. No relationship was observed between CIA-CS and IDH. IDH patients had a significantly higher UF rate; however, they did not differ compared to complication-free patients either in anthropometric or laboratory parameters. Conclusions: Patients with IDH were characterized by lower pre- and post-HD circumferential strain of the common carotid artery. The lower CCA-CS showed that impaired vascular reactivity is one of the most important risk factors for this complication's occurrence.

Prediction of Deterioration of Left Ventricular Function Using 3-Dimensional Speckle-Tracking Echocardiography in Patients With Left Bundle-Branch Block

Background Previous studies have demonstrated that 2-dimensional (2D) global longitudinal strain (GLS) is associated with cardiovascular outcomes in patients with left bundle-branch block. However, the predictive value of 3-dimensional (3D) speckle-tracking echocardiography has not yet been investigated in these patients. Methods and Results The authors retrospectively identified 290 patients with left bundle-branch block who underwent echocardiography more than twice. Using speckle-tracking echocardiography, 2D-GLS, 3D-GLS, 3D-global circumferential strain, 3D global radial strain, and 3D global area strain were acquired. The association between 2D and 3D strains and the follow-up left ventricular (LV) ejection fraction (LVEF) was analyzed. The study population was divided into 2 sets: a group with preserved LVEF (baseline LVEF ≥40%) and a group with reduced LVEF (baseline LVEF <40%). After a median follow-up of 29.1 months (interquartile range, 13.1-53.0 months), 14.9% of patients progressed to LV dysfunction in the group with preserved LVEF, and 51.0% of patients showed improved LV function in the group with reduced LVEF. Multivariable analysis of 2D and 3D strains revealed that higher 2D-GLS (odds ratio [OR], 0.65 [95% CI, 0.54-0.78], P<0.001) was highly associated with maintaining LVEF in patients with preserved LVEF. However, a lower 3D-global circumferential strain (OR, 0.61 [95% CI, 0.47-0.78], P<0.001) showed a strong association with persistently reduced LVEF in patients with reduced LVEF. Conclusions Although 2D-GLS showed a powerful predictive value for the deterioration of LV function in the preserved LVEF group, 3D strain, especially 3D-global circumferential strain, can be helpful to predict consistent LV dysfunction in patients with left bundle-branch block who have reduced LVEF.

The Novel Cardiac Myosin Activator Danicamtiv Improves Cardiac Systolic Function at the Expense of Diastolic Dysfunction In Vitro and In Vivo: Implications for Clinical Applications

Recent cardiotropic drug developments have focused on cardiac myofilaments. Danicamtiv, the second direct myosin activator, has achieved encouraging results in preclinical and clinical studies, thus implicating its potential applicability in the treatment of heart failure with reduced ejection fraction (HFrEF). Here, we analyzed the inotropic effects of danicamtiv in detail. To this end, changes in sarcomere length and intracellular Ca²⁺ levels were monitored in parallel, in enzymatically isolated canine cardiomyocytes, and detailed echocardiographic examinations were performed in anesthetized rats in the absence or presence of danicamtiv. The systolic and diastolic sarcomere lengths decreased; contraction and relaxation kinetics slowed down with increasing danicamtiv concentrations without changes in intracellular Ca²⁺ transients in vitro. Danicamtiv evoked remarkable increases in left ventricular ejection fraction and fractional shortening, also reflected by changes in systolic strain. Nevertheless, the systolic ejection time was significantly prolonged, the ratio of diastolic to systolic duration was reduced, and signs of diastolic dysfunction were also observed upon danicamtiv treatment in vivo. Taken together, danicamtiv improves cardiac systolic function, but it can also limit diastolic performance, especially at high drug concentrations.

Novel approach to artefact detection and the definition of normal ranges of segmental strain and strain-rate values

AIMS

Strain artefacts are known to hamper the correct interpretation of segmental strain and strain-rate (S/SR). Defining the normal ranges of myocardial segmental deformation is important in clinical studies and routine echocardiographic practice. In order to define artefact-free normal ranges for segmental longitudinal S/SR parameters, we investigated the extent to which different types of artefacts and their segmental localisation in the three different myocardial layers created a bias in the results of echocardiographic strain measurements.

METHODS

The study included echocardiograms from men and women aged 40-69 years from two population-based studies, namely the Know Your Heart study (Russia) and the Tromsø Study (Norway). Of the 2207 individuals from these studies, 840 had normal results, defined as the absence of hypertension or indicators of any cardiovascular disease. Two-dimensional (2D) global and segmental S/SR of the three myocardial layers were analysed using speckle tracking echocardiography. Artefacts were assessed with two different methods: visual identification of image-artefacts and a novel conceptual approach of 'curve-artefacts' or unphysiological strain-curve formation.

RESULTS

Segmental strain values were found to have significantly reduced in the presence of strain-curve artefacts (14.9%±5.8% towards -20.7%±4.9%), and increased with the foreshortening of the 2D image. However, the individual global strain values were not substantially altered by discarding segmental artefacts. Reduction due to artefacts was observed in all segments, layers, systolic and diastolic strain, and SR. Thus, we presented normal ranges for basal-septal, basal, medial and apical segment groups after excluding artefacts.

CONCLUSION

Strain-curve artefacts introduce systematic errors, resulting in reduced segmental S/SR values. In terms of artefact-robust global longitudinal strain, the detection of curve-artefacts is crucial for the correct interpretation of segmental S/SR patterns. Intersegmental S/SR gradients and artefacts need to be considered for the correct definition of normalcy and pathology.

Identification of subclinical myocardial dysfunction by Speckle Tracking Imaging in patients with myocardial infarction with non-occlusive coronary arteries (MINOCA)

PURPOSE

The objective of this study was to investigate subclinical left ventricular dysfunction in patients diagnosed with myocardial infarction with non-occlusive coronary arteries (MINOCA).

METHODS

Thirty-five patients with MINOCA (average age 54.26 ± 12.24 years) and thirty-five patients with ischemia with non-obstructed coronary artery disease (INOCA) (average age 55.20 ± 8.36 years) were enrolled in the study. All clinical conditions that could affect left ventricular functions were considered exclusion criteria. Echocardiographic studies were conducted in the patient and control groups in the left lateral decubitus position using a medical ultrasound device (EPIQ 7, Philips Medical System, USA). The left ventricle was examined longitudinally with apical images of chamber 4-3-2 using the available software (QLAB 6.0).

RESULTS

There were no differences in age, blood pressure level, baseline echocardiogram measurements, and tissue Doppler parameters between the two groups. In two-dimensional speckle tracking echocardiography (2D-STE) measurements, left ventricular longitudinal strain and strain rate in systole, early and late diastole from apical 4-3-2 chamber and global measurements of each parameter were significantly decreased in the MINOCA group compared to the INOCA group (p < 0.05). A significant negative correlation was observed between the global longitudinal strain rate and the troponin I in the MINOCA patients group (r=-0.43 p = 0.009).

CONCLUSIONS

Our study showed that while standard echocardiographic parameters for patients diagnosed with MINOCA were normal, their left ventricular systolic and diastolic functions were reduced by the 2D-STE method.

Multimodality imaging in acute myocarditis

The diagnosis of acute myocarditis often involves several noninvasive techniques that can provide information regarding volumes, ejection fraction, and tissue characterization. In particular, echocardiography is extremely helpful for the evaluation of biventricular volumes, strain and ejection fraction. Cardiac magnetic resonance, beyond biventricular volumes, strain, and ejection fraction allows to characterize myocardial tissue providing information regarding edema, hyperemia, and fibrosis. Contemporary cardiac computed tomography angiography (CCTA) can not only be extremely important for the assessment of coronary arteries, pulmonary arteries and aorta but also tissue characterization using CCTA can be an additional tool that can explain chest pain with a diagnosis of myocarditis.

Systolic Strain by Speckle-Tracking Echocardiography Is a Feasible and Sensitive Measure of Right Ventricular Dysfunction in Acute Respiratory Failure Patients on Mechanical Ventilation

Right ventricular (RV) dysfunction is common in acute respiratory failure and associated with worse outcomes, but it can be difficult to detect in the ICU setting. Speckle-tracking echocardiography (STE) can identify early changes in RV systolic function and be quantified as systolic strain. We measured the feasibility of RV global longitudinal systolic strain (RV GLS) in respiratory failure patients and its association with clinical outcomes.

Echocardiographic study of cardiac structure and function in people with bipolar disorder after midlife

BACKGROUND

Heart failure is the leading cause of mortality in older people with bipolar disorder (BD). Studies examining cardiac structure and function in middle-aged patients with BD by using echocardiography and cardiac strain imaging are scant.

METHODS

We recruited 48 patients with bipolar I disorder (BD-I) older than 45 years to undergo conventional and tissue speckle tracking echocardiography. Data of 31 mentally healthy adults older than 45 years were randomly retrieved from the echocardiographic dataset and compared with the data of BD patients.

RESULTS

Patients with BD-I had significantly higher mean values of interventricular septal thickness (Cohen's d = 0.83, p = 0.001) and left ventricular internal diameter (Cohen's d = 0.90, p = 0.001) at end-diastole relative to controls. Additionally, BD-I patients exhibited significantly lower mean values of mitral valve E/A ratio (Cohen's d = 0.67, p = 0.007) and a more reduced global longitudinal strain (Cohen's d = 0.72, p = 0.029) than controls. Multiple linear regression revealed that body mass index was negatively correlated with the mitral valve E/A ratio (adjustment R² = 0.363, p = 0.043) in patients with BD-I.

LIMITATIONS

A relatively small sample size may limit generalization.

CONCLUSIONS

After midlife, BD patients exhibit cardiac diastolic (low mitral valve E/A ratio) and systolic (reduced global longitudinal strain) dysfunction. High body mass index may play a role in the unfavorable cardiac function in aging patients with BD.

Early diastolic strain rate in relation to long term prognosis following isolated coronary artery bypass grafting

BACKGROUND

The ratio of early mitral inflow velocity to early diastolic strain rate (E/e'sr) is a novel echocardiographic measure to estimate early left ventricular (LV) filling pressure. We hypothesize that E/e'sr is a predictor of outcome following coronary artery bypass grafting (CABG) and that it is superior to the conventionally used E/e'.

METHODS & RESULTS

Consecutive patients undergoing isolated CABG at Gentofte Hospital (n = 652) were included. The mean age of the study population was 67 ± 9 years, 84% were male, mean LVEF was 50 ± 11%. Prior to surgery, all patients underwent an extensive echocardiographic examination. The outcome was all-cause mortality. During follow-up (median 3.8 years [IQR: 2.7; 4.9 years]), a total of 73 (11.2%) died. Both E/e' and E/e'sr were significant predictors in univariable models. In a multivariable model, E/e'sr remained an independent predictor of outcome (HR:1.05 [1.01-1.10], p = 0.049, per 10 cm increase) whereas E/e' did not (HR:1.05 [0.99-1.11], p = 0.053, per 1-unit increase). The relationship between E/e'sr, and the outcome was significantly modified by GLS (p for interaction = 0.043). In the multivariable model, E/e'sr was still significantly associated with the outcome in patients with high GLS (≥13.6%) (HR:1.18 [1.02-1.36], p = 0.029) but not in patients with low GLS (HR 1.04 CI95%: [0.99-1.10], p = 0.14). E/e' was not a significant predictor of all-cause mortality after multivariable adjustment in neither of the groups. E/e'sr improved net reclassification with 33% when added to EuroSCOREII.

CONCLUSION

Following CABG, preoperative E/e'sr is an independent predictor of all-cause mortality, especially in patients with preserved systolic function and superior to E/e'.

Speckle tracking ultrasonography as a new tool to assess diaphragmatic function: a feasibility study

A reliable method of measuring diaphragmatic function at the bedside is still lacking. Widely used two-dimensional (2D) ultrasonographic measurements, such as diaphragm excursion, diaphragm thickness, and fractional thickening (FT) have failed to show clear correlations with diaphragmatic function. A reason for this is that 2D ultrasonographic measurements, like FT, are merely able to measure the deformation of muscular diaphragmatic tissue in the transverse direction, while longitudinal measurements in the direction of contracting muscle fibres are not possible. Speckle tracking ultrasonography, which is widely used in cardiac imaging, overcomes this disadvantage and allows observations of movement in the direction of the contracting muscle fibres, approximating muscle deformation and the deformation velocity. Several studies have evaluated speckle tracking as a promising method to assess diaphragm contractility in healthy subjects. This technical note demonstrates the feasibility of speckle tracking ultrasonography of the diaphragm in a group of 20 patients after an aortocoronary bypass graft procedure. The results presented herein suggest that speckle tracking ultrasonography is able to depict alterations in diaphragmatic function after surgery better than 2D ultrasonographic measurements.

Peripheral arterial response during haemodialysis - is two-dimensional speckle-tracking a useful arterial reactivity assessment tool?

Aim: 2D speckle tracking is a method used in myocardial strain assessment. However, several studies have confirmed the suitability of its application in the assessment of arterial strain (a marker of arterial stiffness). The aims of our study were to evaluate whether 2D speckle tracking can assess the changes in carotid and femoral strain caused by fluid loss during haemodialysis, and to determine the direction and amount of these changes. Material and methods: We examined the distal common carotid and proximal femoral arteries in 74 haemodialysed patients (28 women and 46 men) before and after their haemodialysis sessions. EchoPac software was used to analyse the recorded ultrasound examinations. Circumferential strain values were acquired for further analysis. Results: We found a decrease in carotid circumferential strain values after haemodialysis sessions (5.916 ± 2.632% before haemodialysis and 4.909 ± 2.409% after haemodialysis, p = 0.000022). The amount of fluid lost during haemodialysis sessions correlated (correlation coefficient of 0.434, p = 0.000222) with the decrease of carotid circumferential strain. The correlation coefficients were slightly higher (0.445, p = 0.000146) when a ratio of fluid loss volume to the BMI was used. No statistically significant changes were found in femoral circumferential strain. Conclusions: Our findings suggest that arterial response to body fluid loss may be assessed by 2D speckle tracking. This method enabled us to measure carotid circumferential strain changes caused by fluid volume contraction during haemodialysis sessions. We found an important decrease in the carotid circumferential strain values after the procedure. The amount of this decrease correlated significantly with the decrease in the volume of fluid lost during the haemodialysis session.

An image registration framework to estimate 3D myocardial strains from cine cardiac MRI in mice

Accurate and efficient quantification of cardiac motion offers promising biomarkers for non-invasive diagnosis and prognosis of structural heart diseases. Cine cardiac magnetic resonance imaging remains one of the most advanced imaging tools to provide image acquisitions needed to assess and quantify in-vivo heart kinematics. The majority of cardiac motion studies are focused on human data, and there remains a need to develop and implement an image-registration pipeline to quantify full three-dimensional (3D) cardiac motion in mice where ideal image acquisition is challenged by the subject size and heart rate and the possibility of traditional tagged imaging is hampered. In this study, we used diffeomorphic image registration to estimate strains in the left ventricular wall in two wild-type mice and one diabetic mouse. Our pipeline resulted in a continuous and fully 3D strain map over one cardiac cycle. The estimation of 3D regional and transmural variations of strains is a critical step towards identifying mechanistic biomarkers for improved diagnosis and phenotyping of structural left heart diseases including heart failure with reduced or preserved ejection fraction.

Assessing Left Ventricular Early Diastolic Velocities With Tissue Doppler and Speckle Tracking by Transesophageal and Transthoracic Echocardiography

BACKGROUND

Assessing diastolic dysfunction is essential and should be part of every routine echocardiography examination. However, clinicians routinely observe lower mitral annular velocities by transesophageal echocardiography (TEE) under anesthesia than described by awake transthoracic echocardiography (TTE). It would be important to know whether this difference persists under constant loading conditions. We hypothesized that mean early diastolic mitral annular velocity, measured by tissue Doppler imaging (TDI, JOURNAL/asag/04.03/00000539-202105000-00029/inline-graphic1/v/2021-04-15T211206Z/r/image-tiff) would be different in the midesophageal 4-chamber (ME 4Ch) than in the apical 4-chamber (AP 4Ch) view under unchanged or constant loading conditions. Secondarily we examined (1) JOURNAL/asag/04.03/00000539-202105000-00029/inline-graphic2/v/2021-04-15T211206Z/r/image-tiff in an alternative transesophageal view with presumed superior Doppler beam alignment, the deep transgastric view (DTG), compared to those in the AP 4Ch, and (2) early diastolic speckle tracking-based strain rate (JOURNAL/asag/04.03/00000539-202105000-00029/inline-graphic3/v/2021-04-15T211206Z/r/image-tiff), in the ME 4Ch and in the AP 4Ch.

METHODS

Twenty-five consecutive adult patients undergoing on-pump cardiac surgery from February 2017 to July 2017 were included. Both TTE and TEE measurements were obtained under anesthesia in a randomized order in the AP 4Ch, ME 4Ch, and DTG views. Within-patient average values were compared by paired t tests with a Bonferroni adjustment. Box plots, correlation, and agreement by Bland-Altman were examined for all 3 comparisons. A second echocardiographer independently acquired and analyzed images; images were reanalyzed after 4 weeks. Image quality and reproducibility were also reported.

RESULTS

Averaged JOURNAL/asag/04.03/00000539-202105000-00029/inline-graphic4/v/2021-04-15T211206Z/r/image-tiff measurements were lower in the ME 4Ch than in the AP 4Ch (6.6 ± 1.7 cm/s vs 7.0 ± 1.5 cm, P = .028; within-patient difference mean ± standard deviation: 0.6 ± 1.2 cm/s). An alternative TEE view for JOURNAL/asag/04.03/00000539-202105000-00029/inline-graphic5/v/2021-04-15T211206Z/r/image-tiff, the DTG, also exhibited lower mean values (6.0 ± 1.6 cm/s, P = .006; within-patient difference mean ± standard deviation: 1.1 ± 1.8 cm/s). JOURNAL/asag/04.03/00000539-202105000-00029/inline-graphic6/v/2021-04-15T211206Z/r/image-tiff strain rate showed a low degree of bias, but greater variability (ME 4Ch: 0.87 ± 0.32%/s vs AP 4Ch: 0.73 ± 0.18%/s, P = .078; within-patient difference mean ± standard deviation: -0.1 ± 0.2%/s).

CONCLUSIONS

This study confirms that TEE modestly underestimates JOURNAL/asag/04.03/00000539-202105000-00029/inline-graphic7/v/2021-04-15T211206Z/r/image-tiff but not to a clinically relevant extent. While JOURNAL/asag/04.03/00000539-202105000-00029/inline-graphic8/v/2021-04-15T211206Z/r/image-tiff in the DTG is not a promising alternative, the future role for speckle tracking-based early diastolic strain rate is unknown.

Magnetic Resonance Myocardial Feature Tracking in Transfusion-Dependent Myelodysplastic Syndrome

BACKGROUND

Myocardial deformation with echocardiography allows early detection of systolic dysfunction and is related to myocardial iron overload (MIO) determined by T2* in hereditary anemias under transfusion support. Our aim was to analyze the diagnostic and prognostic usefulness of magnetic resonance feature tracking (MR-FT) myocardial strain in low-risk myelodysplastic syndromes (LR-MDS) patients.

METHODS

Prospective study in transfusion-dependent LR-MDS patients and healthy controls who underwent a cardiac MR-FT. We analyzed the relationships between strain MR-FT and iron overload parameters and its prognostic impact in cardiovascular events and/or death.

RESULTS

Thirty-one patients and thirteen controls were included. MIO (T2* < 20 ms) was detected in 9.7% of patients. Left ventricular global longitudinal strain (LV-GLS) by MR-FT was pathological (> −19.3%) in 32.3% of patients. Less negative strain values correlated with lower T2* (R = −0.37, p = 0.033) and native myocardial T1 (R = −0.39, p = 0.031) times. LV-GLS by MR-FT was significantly associated with higher incidence of the combined cardiovascular events and/or all-cause death (p = 0.047), with a cut-off value of −17.7% for predicting them (63% sensitivity and 81% specificity, area under the curve = 0.69). After adjusting analysis including demographic, biomarkers and imaging variables, a higher LV-GLS value by MR-FT remained as predictor of combined event in transfusion-dependent LR-MDS patients (hazard ratio, 0.4; confidence interval, 0.15–0.98; p = 0.045).

CONCLUSIONS

Longitudinal myocardial strain by MR-FT in LR-MDS patients is associated to MIO and correlates with adverse events in the follow-up, what could serve as a prognostic tool.

Speckle tracking echocardiography in severe patient-prosthesis mismatch

BACKGROUND

Although aortic valve replacement (AVR) when successfully performed boasts low mortality rates in selected patients, prosthesis-patient mismatch (PPM) can be found in the majority of these individuals. Limited research is available supporting the benefit of two-dimensional speckle tracking echocardiography (2D-STE) in patients with severe PPM. This study sought to assess myocardial strain using 2D-STE to determine the relationship between subclinical left ventricular (LV) dysfunction and aortic PPM in patients undergoing AVR with preserved LV ejection fraction.

MATERIAL AND METHODS

We retrospectively examined all consecutive patients with isolated AVR who presented to our center from 2005 to 2018. The data of 1086 patients were analyzed. Severe PPM was defined as an indexed effective orifice area of 0.65 cm²/m² or less. As a result of the detailed assessment, 54 patients meeting the eligibility criteria were included in the study. Baseline data were collected and compared between the two groups of patients with severe PPM (n = 27) and those with normofunctional aortic prosthesis valve as a control group (n = 27). All patients underwent baseline echocardiography. Global longitudinal strain (GLS) and global circumferential strain (GCS) were evaluated by 2D-STE.

RESULTS

When compared with controls, patients with severe PPM had significantly decreased GLS (18.6 ± 2.9 vs. 21.4 ± 2.1; p < 0.01) and GCS (17.2 ± 3.6 vs. 21.7 ± 2.1; p < 0.01) values.

CONCLUSION

In addition to standard clinical and echocardiographic parameters, GLS and GCS suggest subclinical dysfunction and have incremental value in patients with severe PPM.

New mutation in Fabry disease: c.448delG, first phenotypic description

Fabry disease (FD) (Anderson-Fabry disease, OMIM 301500) is a genetic disorder caused by a pathogenic variant in the GLA gene on chromosome Xq22 that produces a deficiency in the lysosomal enzyme alpha-galactosidase A.

It is transmitted as an X-linked trait, although de novo mutations have been described. The objective of this report is to describe the clinical characteristics of a patient with FD who is a carrier of a mutation not previously studied, in order to provide information on the genotype-phenotype correlation in this pathology.

38-year-old patient who consulted Neurology for positional vertigo. He also reported acroparesthesia, anhidrosis, heat intolerance and episodes of abdominal pain, with postprandial discomfort from 10 years of age. Physical examination showed horizonto-rotatory nystagmus in both looks, the rest of the neurological evaluation did not present abnormalities. The presence of umbilical and thighs angiokeratomas was identified. Determination of Alpha-Galactosidase in blood was requested: 0.34 μmol/l/h (2.10–10.51 μmol/l/h). Genetic analysis detected a deletion of a guanine at position 448, in exon 3 of the GLA gene (c.448delG). This mutation was considered to be pathogenic, confirming the diagnosis of FD, although it is not described in the data bases. Genetic counseling and a family pedifree study were performed without finding relatives with this variant of the GLA gene or a family history of FD, which suggests a de novo mutation.

Prognostic value of left ventricular mitral annular longitudinal displacement obtained by tissue Doppler imaging in patients with heart failure with reduced ejection fraction

Background

Tissue Doppler imaging (TDI) can be used to measure the mitral annular longitudinal displacement (LD) during systole. However, the prognostic utility of global and regional LD in patients with heart failure with reduced ejection fraction (HFrEF) is unknown.

Methods

Echocardiographic examinations from 907 patients with HFrEF were analysed obtaining conventional echocardiographic measurements. Regional LD was obtained from colour TDI projections in six mitral annular regions and global LD was calculated as an average.

Results

Mean age was 67 years, 26.9% were women and mean left ventricular ejection fraction was 27%. During a median follow-up period of 40 months, 150 (16.5 %) patients died. The risk of dying increased with decreasing tertile of global LD and was approximately five times higher for patients in the lowest tertile compared with the highest (1. tertile vs 3. tertile, HR 4.9, 95% CI: 3.0 to 7.9, p<0.001).

Global LD was a significant independent predictor of mortality after adjusting for age, gender, body mass index, pacemaker, heart rate, atrial fibrillation, diabetes and conventional echocardiographic measures and global longitudinal strain: HR 1.16 (95% CI: 1.00 to 1.34, p=0.044) per 1 mm decrease.

For regional measures, inferior LD was also a significant independent predictor in the multivariable model: HR 1.16 (95% CI: 1.04 to 1.29, p=0.006) and adding inferior LD to the conventional measures yielded a significant increase in Harrell’s C-statistic (95% CI: 0.75 to 0.78, p=0.009).

Conclusion

In patients with HFrEF, global and inferior LD are independent predictors of all-cause mortality. Furthermore, inferior LD proved to be a significant prognosticator when compared with all the conventional echocardiographic parameters.

Right Ventricular Longitudinal Strain Predicts Survival in Patients With Functional Tricuspid Regurgitation

BACKGROUND

Functional tricuspid regurgitation (TR) is a frequent finding in echocardiography. Despite general consent that right ventricular (RV) dysfunction impacts outcome of patients with TR, it is still unknown which echocardiographic parameters most accurately reflect prognosis. In this study we aimed to evaluate the prevalence of RV dysfunction and its prognostic value in patients with TR.

METHODS

Data from 1089 consecutive patients were analysed. Tricuspid annular plane systolic excursion (TAPSE), fractional area change, and right ventricular free wall longitudinal strain (RV strain) were used to define RV dysfunction. Patients were followed for 2-year all-cause mortality. For prediction of survival, reclassification and C statistics of RV functional parameters using TR grade as reference model were performed.

RESULTS

Among the patients studied, 13.9% showed no TR, 61.2% had mild TR, 19.6% had moderate TR, and 5.3% had severe TR. The TR grade was associated with increased mortality (log rank, P < 0.001). Impaired RV strain and TAPSE were independent predictors for mortality (RV: hazard ratio [HR], 1.130; 95% confidence interval [CI], 1.099-1.160; P < 0.001; TAPSE: HR, 1.131; 95% CI, 1.085-1.175; P < 0.001). Both RV strain and TAPSE improved the reference model for survival prediction (RV: integrated discrimination improvement [IDI], 0.184; 95% CI, 0.146-0.221; P < 0.001; TAPSE: IDI, 0.057; 95% CI, 0.037-0.077; P < 0.001).

CONCLUSIONS

Echocardiographic evaluation of RV function appears to useful for patients with TR. Assessment of RV strain provides additional value for prediction of 2-year mortality.

Left atrial strain: a multi-modality, multi-vendor comparison study

AIMS

Left atrial (LA) strain is a prognostic biomarker with utility across a spectrum of acute and chronic cardiovascular pathologies. There are limited data on intervendor differences and no data on intermodality differences for LA strain. We sought to compare the intervendor and intermodality differences between transthoracic echocardiography (TTE) and cardiac magnetic resonance (CMR) derived LA strain. We hypothesized that various components of atrial strain would show good intervendor and intermodality correlation but that there would be systematic differences between vendors and modalities.

METHODS AND RESULTS

We evaluated 54 subjects (43 patients with a clinical indication for CMR and 11 healthy volunteers) in a study comparing TTE- and CMR-derived LA reservoir strain (ƐR), conduit strain (ƐCD), and contractile strain (ƐCT). The LA strain components were evaluated using four dedicated types of post-processing software. We evaluated the correlation and systematic bias between modalities and within each modality. Intervendor and intermodality correlation was: ƐR [intraclass correlation coefficient (ICC 0.64-0.90)], ƐCD (ICC 0.62-0.89), and ƐCT (ICC 0.58-0.77). There was evidence of systematic bias between vendors and modalities with mean differences ranging from (3.1-12.2%) for ƐR, ƐCD (1.6-8.6%), and ƐCT (0.3-3.6%). Reproducibility analysis revealed intraobserver coefficient of variance (COV) of 6.5-14.6% and interobserver COV of 9.9-18.7%.

CONCLUSION

Vendor derived ƐR, ƐCD, and ƐCT demonstrates modest to excellent intervendor and intermodality correlation depending on strain component examined. There are systematic differences in measurements depending on modality and vendor. These differences may be addressed by future studies, which, examine calibration of LA geometry/higher frame rate imaging, semi-quantitative approaches, and improvements in reproducibility.

Prognostic Value of Left Ventricular Global Strain Analysis by Two-Dimensional Speckle-Tracking Echocardiography in Non-Hemodynamically Significant Intermediate Coronary Lesions

Intermediate coronary lesions represent a major challenge for the invasive and noninvasive cardiologist. Left ventricular strain calculation by speckle tracking echocardiography has the capacity to analyze the motion of the cardiac tissue. This study aimed to evaluate its usefulness and prognostic significance in nonhemodynamically significant intermediate coronary lesions. We studied 247 patients who underwent a clinically indicated coronary angiogram. Each of the patients had a single nonrevascularized nonhemodynamically significant intermediate severity coronary lesion (ISCL) with a fractional flow reserve greater than 0.80. The left ventricular global longitudinal strain (GLS) was calculated using speckle-tracking echocardiography with TomTec 2D Cardiac Performance Analysis (Unterschleissheim, Germany). An abnormal GLS was defined as less than -20%. The primary endpoints were revascularization of the target lesion, admissions for major adverse cardiac events (MACE), and cardiac-related mortality, all within 2 years. On multivariate logistic regression data analysis, we found that patients with an ISCL and abnormal GLS had an increased risk for admissions due to MACE (odds ratio [OR] 1.06, P < 0.05, confidence interval [CI] 95%, 1.005-1.120], and an increased risk of cardiac-related death (OR 1.12, P < 0.05, CI 95% 1.012-1.275). There was no difference in the need for target lesion revascularization among individuals with normal and abnormal GLS (1.00, P 0.88, CI 95% .950-1.061). Left ventricular strain analysis by speckle-tracking echocardiography showed an independent prognostic value in patients with nonrevascularized nonhemodynamically significant coronary lesions.

Nazmy N, Bastawy I, Raafat S. A Subtle Decline in Cardiac Mechanics is correlated with Albuminuria in Asymptomatic Normotensive Patients with Type 2 Diabetes Mellitus: A Two Dimensional Strain Echocardiography Study

Background:

Type 2 diabetes mellitus (T2DM) insidiously affects the myocardium with subsequent cardiomyopathy and induces microvascular damage in the kidneys reflected by albuminuria. We aimed to investigate the relationship between albuminuria and subclinical left ventricular (LV) systolic dysfunction in asymptomatic normotensive patients with T2DM assessed by two-dimensional speckle-tracking echocardiography.

Materials and Methods and Results:

Sixty normotensive patients with T2DM were included and subdivided into two subgroups, each including thirty patients according to the presence of albuminuria, together with thirty control subjects. All underwent echocardiographic examination, including LV regional and global longitudinal strain (GLS) measurements. Laboratory tests were withdrawn, including serum glycated hemoglobin (HbA1C) and albumin–creatinine ratio (ACR). When compared to the control group, patients with T2DM had a significantly lower average peak systolic LV GLS (−16.18% ± 2.78% vs. −18.13% ± 2.86%, P < 0.001), however, there was no significant difference in average peak systolic LV GLS between both diabetic subgroups (−15.57% ± 2.77% in the albuminuric subgroup vs. −16.79% ± 2.70% in the nonalbuminuric subgroup, P = 0.077). Moreover, there was a significant correlation between ACR and reduction of GLS in patients with T2DM and albuminuria (r = 0.55, P = 0.002). However, this correlation was absent in patients with T2DM without albuminuria (r = 0.107, P = 0.573).

Conclusions:

Patients with T2DM have subclinical LV systolic dysfunction with a reduction of average LV GLS that correlates with ACR in patients with T2DM and albuminuria.

Assessment of atrial function by myocardial deformation techniques in hypertrophic cardiomyopathy

BACKGROUND

Diastolic dysfunction in hypertrophic cardiomyopathy (HCM) is common, but its assessment is difficult using conventional echocardiography.

AIMS

To assess left atrial (LA) function in HCM by longitudinal strain and determine its role in understanding of symptoms.

METHODS

We studied 144 patients divided into 3 age- and sex-matched groups: 48 consecutive patients with HCM, 48 control subjects, and 48 athlete subjects. We assessed LA function by conventional echocardiographic parameters and by longitudinal atrial strain (early-diastolic left atrial strain during reservoir phase [LASr]; end-diastolic left atrial strain during conduit phase; end-systolic peak of the left atrial strain during contraction phase).

RESULTS

NYHA classification was as follows in HCM group: I in 46%, II in 31%, III in 19%, and IV in 4%. Conventional echocardiographic parameters of diastolic function were depressed in the HCM group as compared to the control and athlete groups, but not related to symptoms. All longitudinal atrial strain parameters were significantly reduced in HCM group as compared to two groups (P < .0001). LASr was significantly correlated to peak VO2 (r = 0.44, P = .01) and was the best parameter for detecting symptomatic patients presenting with HCM, with a cutoff value of 15%: Sensitivity was 71%, specificity was 79%, PPV was 77%, and NPV was 73%.

CONCLUSION

Assessment of LA function in HCM is feasible using longitudinal strain, and this technique is more reliable than conventional echocardiographic parameters for the understanding of determinants of symptoms.

Left ventricular myocardial deformation as measure of hemodynamic burden in congenital valvular aortic stenosis

BACKGROUND

Changes in 2D echocardiography (2DE) speckle tracking imaging (STI) derived left ventricular (LV) strain (S) and strain rate (SR) precedes diminution of LV ejection fraction (LVEF) in adult valvular aortic stenosis (AS). We prospectively examined whether 2DE-STI derived multidirectional LV S and SR correlate with AS severity in children using LV mass index (MI) as the principal outcome variable.

METHODS

52 children (10.4 ± 7.3 years) with isolated congenital AS were included; 13 mild (2.5 m/s < V_max < 3.0 m/s), 25 moderate (3.0 m/s < V_max < 4.0 m/s), and 14 severe (V_max > 4.0 m/s). 2DE including Doppler and STI longitudinal strain (LS), strain rate (LSR), circumferential strain (CS), and strain rate (CSR) were measured. Univariate and multivariable linear regressions identified correlations between LVMI and strain indices.

RESULTS

Three clinical and 2DE variables, and four strain indices were independently associated with LVMI. LVMI correlated positively with systolic blood pressure and aortic regurgitation, and negatively with LVEF. LVMI correlated positively with LSR (four-chamber) and CSR (basal), and negatively with segmental CS in the inferior (basal) and anteroseptal (distal) segments. LVMI showed significant inverse association with LS (P = .05), LSR (P < .001), CS (P < .005), and CSR (P < .0001), independent of AS severity.

CONCLUSIONS

Independent of clinical and 2DE findings including contemporaneous Doppler estimates of AS gradient, both longitudinal and circumferential strain indices correlate with LVMI as a measure of cumulative hemodynamic burden. This association implies subclinical LV dysfunction.

Longitudinal diastolic strain slope as an early sign for systolic dysfunction among patients with active cancer

BACKGROUND

Diastolic dysfunction is a common finding in patients receiving cancer therapy. This study evaluated the correlation of diastolic strain slope (Dss) with routine echocardiography diastolic parameters and its role in early detection of systolic dysfunction and cardiovascular (CV) mortality within this population.

METHODS

Data were collected from the Israel Cardio-Oncology Registry (ICOR), a prospective registry enrolling adult patient receiving cancer therapy. All patients performed at least three echocardiography exams (T1, T2, T3), including left ventricle Global Longitudinal Strain (LV GLS) and Dss. Systolic dysfunction was determined by either LV GLS relative reduction of ≥ 15% or LV ejection fraction reduction > 10% to < 53%. Dss was assessed as the early lengthening rate, measured by the diastolic slope (delta%/sec).

RESULTS

Among 144 patients, 114 (79.2%) were female with a mean age of 57.31 ± 14.3 years. Dss was significantly correlated with e' average. Mid segment Dss change between T1 and T2 showed significant association to systolic dysfunction development (Odds Ratio (OR) = 1.04 [1.01,1.06]. p = 0.036). In multivariate prediction, Dss increase was a significant predictor for the development of systolic dysfunction (OR = 1.06 [1.03,1.1], P < 0.001).An 8% increase in Dss between T1 and T2 was associated with a trend in increased CV mortality (HR = 3.4 [0.77,15.4], p = 0.085).

CONCLUSIONS

This study is the first to use the novel measurement of Dss in patients treated with cancer therapies and to show significant correlation between routine diastolic dysfunction parameters and Dss. Changes in the mid segment were found to have significant independent early predictive value for systolic dysfunction development in univariate and multivariate analyses.

Quantitative assessment of contractile reserve of systemic right ventricle in post-Senning children: Incorporating speckle-tracking strain and dobutamine stress echocardiography

INTRODUCTION

The systemic load on the right ventricle (RV) after Senning atrial switch leads to ventricular dysfunction. Quantitative assessment of RV contractile reserve is mandatory to anticipate the need for anti-fibrotic treatment. We aimed to quantitatively assess RV contractile reserve in Senning children by estimating speckle-based global longitudinal strain (GLS) during dobutamine stress echocardiography (DSE).

METHODS

This prospective study compared thirty-one post-Senning children (group I) and thirty controls (group II). In post-Senning children, echocardiographic RV systolic function using one-plane ejection fraction (RVEF), RV fractional area change (RVFAC), tricuspid annulus plane systolic excursion (TAPSE), its Z-score, and RVGLS were recorded at rest and peak DSE. Contractile reserve was defined as improvement >5% in RVEF, >2% in GLS, and/or to near normal TAPSE.

RESULTS

RVEF, RVFAC, TAPSE, and TAPSE Z-score were significantly lower in patients than controls [RVEF:40.13 ± 2.93% vs 53.17 ± 3.17% (P < .001*), RVFAC: 21.17 ± 2.37% vs 37.23 ± 2.13% (P < .001*), TAPSE:13.81 ± 1.26 vs 17.45 ± 2.93 mm (P < .001*), TAPSE Z-score: -3.47 ± 0.46 vs -2.09 ± 0.48 (P < .001*)]. Also, RVGLS was significantly impaired in Senning children than controls[ (-11.89 ± 2.31% vs -22.35 ± 6.73% (P < .001*)]. At peak DSE, contractile reserve was not evident as measured by RVEF which increased none significantly to 42.47 ± 2.80% (P = .063). However, RVGLS improved significantly to -15.78 ± 0.93% (P < .001*) and discovered the masked contractile reserve in Senning children. The 19(61.29%) children who showed masked contractile reserve (improvement in RVGLS > 2%) underwent continuation of anti-fibrotic medications.

CONCLUSIONS

Despite systemic RV function in post-Senning children was impaired at rest and during DSE, RVGLS was useful in quantitative assessment of masked contractile thus promoted continuing anti-fibrotic treatment.

Impact of 2 different aerobic periodization training protocols on left ventricular function in patients with stable coronary artery disease: an exploratory study

We compared the impacts of linear (LP) and nonlinear (NLP) aerobic training periodizations on left ventricular (LV) function and geometry in coronary artery disease (CAD) patients. Thirty-nine CAD patients were randomized to either a 3-month isoenergetic supervised LP or NLP. All underwent standard echocardiography with assessment of 3D LV ejection fraction (LVEF), diastolic function, strain (global longitudinal, radial, and circumferential), and strain rate at baseline and study end. Training was performed 3 times/week and included high-intensity interval and moderate-intensity continuous training sessions. Training load was progressively increased in the LP group, while it was deeply increased and intercepted with a recovery week each fourth week in the NLP group. For the 34 analyzed patients, we found similar improvements for 3D LVEF (effect size (ES): LP, 0.29; NLP, 0.77), radial strain (ES: LP, 0.58; NLP, 0.48), and radial strain rate (ES: LP, 0.87; NLP, 0.17) in both groups (time for all: p ≤ 0.01). All other parameters of cardiac function remained similar. In conclusion, NLP and LP led to similar improvements in 3D LVEF and radial strain, suggesting a favourable positive cardiac remodelling through myofibers reorganization. These findings must be investigated in patients with more severe cardiac dysfunction. The study was registered on ClinicalTrials.gov (NCT03443193). Novelty: Linear and nonlinear periodization programs improved radial strain, accompanied by improvement of ejection fraction. Both aerobic periodization programs did not negatively impact cardiac function in coronary artery disease patients.

Myocardial strain imaging: review of general principles, validation, and sources of discrepancies

Myocardial tissue tracking imaging techniques have been developed for a more accurate evaluation of myocardial deformation (i.e. strain), with the potential to overcome the limitations of ejection fraction (EF) and to contribute, incremental to EF, to the diagnosis and prognosis in cardiac diseases. While most of the deformation imaging techniques are based on the similar principles of detecting and tracking specific patterns within an image, there are intra- and inter-imaging modality inconsistencies limiting the wide clinical applicability of strain. In this review, we aimed to describe the particularities of the echocardiographic and cardiac magnetic resonance deformation techniques, in order to understand the discrepancies in strain measurement, focusing on the potential sources of variation: related to the software used to analyse the data, to the different physics of image acquisition and the different principles of 2D vs. 3D approaches. As strain measurements are not interchangeable, it is highly desirable to work with validated strain assessment tools, in order to derive information from evidence-based data. There is, however, a lack of solid validation of the current tissue tracking techniques, as only a few of the commercial deformation imaging softwares have been properly investigated. We have, therefore, addressed in this review the neglected issue of suboptimal validation of tissue tracking techniques, in order to advocate for this matter.

Strain Curve Classification Using Supervised Machine Learning Algorithm with Physiologic Constraints

Speckle tracking echocardiography (STE) enables quantification of myocardial deformation by a generation of spatiotemporal strain curves or time-strain curves (TSCs). Currently, only assessment of peak global longitudinal strain is employed in clinical practice because of the uncertainty in the accuracy of STE. We describe a supervised machine learning, physiologically constrained, fully automatic algorithm, trained with labeled data, for classification of TSCs into physiologic or artifactual classes. The data set of 415 healthy patients, with three cine loops per patient, corresponding to the three standard 2-D longitudinal views, was processed using a previously published, in-house STE software termed K-SAD. We report an accuracy of 86.4% for classifying TSCs as physiologic, artifactual and undetermined curves. The positive predictive value for a physiologic strain curve is 89%. This is as a necessary step for a similar separation of pathologic conditions, to allow full utilization of the temporal information concealed in layer-specific segmental TSCs.

Speckle tracking echocardiography for the evaluation of left ventricular function in children with systemic lupus erythematosus

BACKGROUND

Many studies in adult patients with systemic lupus erythematosus (SLE) have demonstrated that myocardial dysfunction was significantly associated with enhanced disease activity. However, similar studies in paediatric patients with SLE are limited. The aim of this study was to evaluate the role of speckle tracking echocardiography (STE) to detect left ventricular dysfunction in children with active and inactive SLE.

METHODS

This prospective case-control study was carried out on 50 children with SLE. Thirty healthy age- and sex-matched children comprised the control group. The patients were further subdivided into two subgroups: active SLE and inactive SLE. Laboratory investigations undertaken included complete blood count, renal function, C3, C4, ANA, anti-dsDNA and serum N-terminal pro-B type natriuretic peptide. Echocardiographic examinations were performed on all children and included conventional echocardiography, tissue Doppler imaging (TDI) and two- and three-dimensional STE.

RESULTS

There was no statistically significant difference in N-terminal pro B natriuretic peptide between the studied groups. The myocardial performance index by TDI was statistically significantly higher in SLE patients compared to controls. STE parameters were statistically significantly lower in SLE patients compared to controls. There was no correlation between STE parameters and disease activity.

CONCLUSIONS

STE could be a promising technique in the early detection of subclinical left ventricular dysfunction in children with SLE.

Correlation between global longitudinal strain and SYNTAX score in coronary artery disease evaluation

BACKGROUND

Speckle tracking echocardiography may allow the evaluation of myocardial systolic and diastolic dynamics across different physiologic and pathologic conditions beyond traditional echocardiographic techniques. The use of STE longitudinal strain in identification and risk stratification of CAD has good reproducibility and accuracy. The study aims to detect the relationship between SYNTAX score and global longitudinal peak systolic strain (GLPSS) in patients undergoing coronary angiography, with no history of myocardial infarction.

RESULTS

The study included 70 symptomatic patients suspected to have chronic coronary syndrome aging 20-80 years (excluding those with significant structural heart disease). All patients underwent clinical evaluation, surface ECG, laboratory assessment, transthoracic echocardiographic (TTE), color TDI tracings, two-dimensional speckle tracking, and conventional coronary angiography with SYNTAX score calculation. Patients were divided into 3 groups based on the results of the coronary angiogram: normal CAD on angiogram (n = 10, control group), low SS (n = 25, SS < 22), and high SS (n = 35, SS ≥ 22). The mean age was 55 ± 9.6 years; 54% were males; two third of patients were hypertensive; 52% were diabetic; high percentage of high syntax score were noticed among males, diabetic patients, and smokers; and also low mean of GLS was noticed among diabetic patients and smokers. There was a statistically significant positive correlation between syntax score and each of LVEDD and LVESD and, on the other hand, statistically significant negative correlation between syntax score and each of E/A, GLS, AP2LS, AP3LS, and AP4LS was noticed. Peak GLS cutoff value of 17.8 and 16.5 showed 84% and 93% sensitivity and 70% and 91% specificity to detect high and low syntax score, respectively.

CONCLUSION

2D longitudinal strain analysis has incremental diagnostic value over visual assessment during echocardiography in predicting significant coronary artery disease; GLS may offer a potential sensitive tool to detect significant CAD.

The Utility of Cardiac Reserve for the Early Detection of Cancer Treatment-Related Cardiac Dysfunction: A Comprehensive Overview

With progressive advancements in cancer detection and treatment, cancer-specific survival has improved dramatically over the past decades. Consequently, long-term health outcomes are increasingly defined by comorbidities such as cardiovascular disease. Importantly, a number of well-established and emerging cancer treatments have been associated with varying degrees of cardiovascular injury that may not emerge until years following the completion of cancer treatment. Of particular concern is the development of cancer treatment related cardiac dysfunction (CTRCD) which is associated with an increased risk of heart failure and high risk of morbidity and mortality. Early detection of CTRCD appears critical for preventing long-term cardiovascular morbidity in cancer survivors. However, current clinical standards for the identification of CTRCD rely on assessments of cardiac function in the resting state. This provides incomplete information about the heart's reserve capacity and may reduce the sensitivity for detecting sub-clinical myocardial injury. Advances in non-invasive imaging techniques have enabled cardiac function to be quantified during exercise thereby providing a novel means of identifying early cardiac dysfunction that has proved useful in several cardiovascular pathologies. The purpose of this narrative review is (1) to discuss the different non-invasive imaging techniques that can be used for quantifying different aspects of cardiac reserve; (2) discuss the findings from studies of cancer patients that have measured cardiac reserve as a marker of CTRCD; and (3) highlight the future directions important knowledge gaps that need to be addressed for cardiac reserve to be effectively integrated into routine monitoring for cancer patients exposed to cardiotoxic therapies.

Two-dimensional speckle tracking echocardiography in goats: repeatability, variability, and validation of the technique using an exercise test and an experimentally induced acute ischemic cardiomyopathy

Background

Two-dimensional speckle tracking (2DST) technique has been validated in numerous animal species, but neither studies of repeatability nor measurements after exercise or in animals with cardiac disease have been reported in goats. Goats are an attractive candidate for animal models in human cardiology because they are easy to handle and have a body and heart size comparable to that of humans. Therefore, the aim of this study was to validate this technique in goats for further clinical and experimental applications in this species.

Results

This study was divided into several steps. First, a standardized echocardiographic protocol was performed and 5 cineloops of a right parasternal short-axis view at papillary muscles level were recorded three times at one-day intervals in ten healthy adult unsedated Saanen goats to test repeatability and variability of 2DST measurements. Then, the same measurements were performed immediately before and after a standardized exercise on treadmill in seven of the goats, and at 24 h after induction of an experimental ischemic cardiomyopathy in five of the goats, to test the reliability of the technique to assess physiological and pathological changes. Average and regional measurements of radial and circumferential strain and strain rate, radial displacement, rotation and rotation rate were obtained. Comparisons were performed using two-way ANOVA (p < 0.05). Caprine 2DST average measurements have demonstrated a good repeatability with a low to moderate variability for all measurements except for the diastolic peaks of the circumferential strain rate, radial strain rate and rotation rate. Segmental 2DST measurements were less repeatable than average measurements. Time effect of two-way ANOVA was significant for anteroseptal segment diastolic peaks measurements, rotation and rotation rate measurements. Overall variability of segmental measurements was moderate or high. Segmental and average peak values obtained after exercise and after myocardial ischemia were significantly different than curves obtained at baseline.

Conclusions

The results of this study are consistent with those previously described in other animal species and humans. 2DST echocardiography is a valid technique to evaluate physiological and pathological changes in myocardial function in goats, despite the technical limitations observed in this species.

Effect of direct-acting antivirals on corrected QT interval and cardiac functions in patients with chronic hepatitis C virus infection

Background

Hepatitis C virus (HCV) infection is a major public health problem in Egypt. The use of direct-acting antivirals (DAAs) in such patients has been shown to be highly effective. The cardiac safety of such antivirals remains uncertain. This study aimed to assess the effect of the novel DAAs on corrected QT (QTc) interval and on cardiac function using trans-thoracic echocardiography.

Results

This was a prospective cohort study performed on 100 patients suffering from chronic HCV infection. Patients were into two equal groups according to the presence of liver cirrhosis. The group without liver cirrhosis received a daily combination of sofosbuvir 400 mg and daclatasvir 60 mg for 12 weeks while that with liver cirrhosis (Child-Pugh score A or B) received a daily combination of sofosbuvir 400 mg, daclatasvir 60 mg, and ribavirin 600 mg for 12 weeks. Surface ECG and trans-thoracic echocardiography were performed prior to the start of treatment and after 12 weeks of treatment.

At the end of treatment, no changes were observed in QTc interval in those with (p = 0.48) or without (p = 0.048) liver cirrhosis. In patients without liver cirrhosis, right ventricular global longitudinal strain (RV GLS) decreased from 22 (−30 to −17) to −21 (−27–18), p = 0.024. In patients with liver cirrhosis, lateral mitral E’ velocity was reduced from 14.38 ± 3.59 to 13.62 ± 3.21 cm/s, p = 0.02 and indexed left atrial volume (LAVI) was increased from 25.96 ± 3.96 to 26.86 ± 4.12 ml/m², p = 0.032. There were no changes in both groups regarding left ventricular (LV) dimensions, ejection fraction, trans-mitral E/A ratio, E/E’ ratio, deceleration time, right ventricular (RV) systolic pressure, mean pulmonary artery pressure, RV fractional area change, tricuspid annular plane systolic excursion, and LV GLS.

Conclusion

The current national protocol of HCV infection treatment with direct-acting antiviral agents used in Egyptian patients has a good cardiac safety profile. Such treatments have no effect on QTc interval, left and right ventricular functions except for a decrease in RV GLS in those with no liver cirrhosis and a reduction in lateral mitral E’ velocity in those with liver cirrhosis both remained within the normal reference range.

Observational study of left ventricular global longitudinal strain in ST-segment elevation myocardial infarction patients with extended pharmaco-invasive strategy: A six months follow-up study

AIMS AND OBJECTIVES

To evaluate left ventricular (LV) function by assessment of LV global longitudinal strain (GLS) in ST-segment elevation myocardial infarction (STEMI) patients who underwent delayed fibrinolysis and coronary intervention (extended pharmaco-invasive strategy), since LV function is one of the determinants of both immediate and long-term outcomes.

METHODS

Prospective study of consecutive STEMI patients who underwent extended pharmaco-invasive strategy. The LV function was estimated using LV GLS at baseline and at 6 months.

RESULTS

The study included eighty-seven STEMI patients who received delayed pharmaco-invasive therapy and coronary intervention. The primary aim of the study was to evaluate a change in LV function by assessment of GLS at 6 months as compared to baseline. Prior to PCI, LV ejection fraction was 48.08 ± 6.23% and GLS was -11.11 ± 2.99%. Procedural success was achieved in all patients. LV ejection fraction after 6 months of follow-up increased to 53.12 ± 5.61% and the GLS improved to -13.03 ± 3.06% In comparison to baseline, there was a significant improvement in both LV ejection fraction and GLS at 6 months of follow-up (P < .001).The cardiac mortality was 1.1% at 6 months.

CONCLUSION

There is a significant improvement of LV function as assessed by GLS and ejection fraction at short-term follow-up. In a stable cohort of STEMI patients, extended pharmaco-invasive strategy is also a reasonable option if PCI cannot be performed within the first 24 hours, due to logistic and infrastructural constraints.

Left and Right Ventricular Impairment Shortly After Correction of Tetralogy of Fallot

Surgical repair of Tetralogy of Fallot (ToF) is usually performed in the first months of life with low early postoperative mortality. During long-term follow-up, however, both right (RV) and left ventricular (LV) performances may deteriorate. Tissue Doppler imaging (TDI) and speckle tracking echocardiography (ST) can unmask a diminished RV and LV performance. The objective of the current study was to assess the cardiac performance before and shortly after corrective surgery in ToF patients using conventional, TDI and ST echocardiographic techniques. Thirty-six ToF patients after surgery were included. Transthoracic echocardiography including TDI and ST techniques was performed preoperatively and at hospital discharge after surgery (10 days to 4 weeks after surgery). Median age at surgery was 7.5 months [5.5-10.9]. Regarding the LV systolic function there was a significant decrease in interventricular septum (IVS) S' at discharge as compared to preoperatively (pre IVS S' = 5.4 ± 1.4; post IVS S' = 3.9 ± 1.2; p < 0.001) and in global longitudinal peak strain (GLS) (pre = - 18.3 ± 3.4; post = - 14.2 ± 4.1; p = 0.003); but not in the fractional shortening (FS). Both conventional and TDI parameters showed a decrease in diastolic function at discharge. Tricuspid Annular Plane Systolic Excursion and RV S' were significantly lower before discharge. When assessing the RV diastolic performance, only the TDI demonstrated a RV impairment. There was a negative correlation between age at surgery and postoperative LV GLS (R = - 0.41, p = 0.031). There seems to be an impairment in left and right ventricle performance at discharge after ToF corrective surgery compared to preoperatively. This is better determined with TDI and ST strain imaging than with conventional echocardiography.

Short- and mid-term effects of sleeve gastrectomy on left ventricular function with two-dimensional speckle tracking echocardiography in obese patients

AIM

This study aimed to investigate left ventricular functions of obese patients with no known heart disease who underwent laparoscopic sleeve gastrectomy by speckle tracking echocardiography in their early and medium-term postoperative follow-up.

PATIENTS AND METHOD

Thirty-seven obese patients (10 M, 27 F) without coronary artery disease or heart failure who had undergone LSG were included in the study. Apical four-, three-, and two-chamber images were analyzed longitudinally by conventional methods and speckle tracking echocardiography (STE) for left ventricle functions preoperatively, at the postoperative Month 1 and at the postoperative Month 6 (QLAB 6.0), using current software.

RESULTS

No difference was found between standard echocardiography and Doppler parameters in terms of the 1-month versus 6-month follow-up values compared to baseline. Left ventricular STE longitudinal measurements demonstrated significantly higher longitudinal strain and strain velocity parameters in the follow-up values at Month 6 compared to the values at Month 1 and at baseline. Global longitudinal strain (GLS) was -17.48 ± 1.09% in 6-month follow-up, -16.16 ± 1.26% in 1-month follow-up, and -16.06 ± 1.25% at baseline (P < .001). A significant correlation was found between delta GLS, which represents patients' GLS change in 6 months, and delta weight, which represents patients' body weight change in 6 months.

CONCLUSION

Obese patients who had undergone LSG were observed to have improved left ventricular function in the mid-term.

Evolution of strain and strain rate values throughout gestation in healthy fetuses

Myocardial deformation by speckle tracking echocardiography is a novel method for evaluating cardiac function. To test the hypothesis that right ventricular and left ventricular function have age-specific patterns of development, we tracked the evolution of ventricular strain mechanics by speckle tracking echocardiography in the fetus. We conducted a retrospective cross sectional echocardiography study in 154 healthy fetuses, and characterized cardiac function by measuring right and left ventricles global longitudinal strain and strain rate. Comparison of the data of both ventricles according to gestational age was carried out. The magnitudes of right and left ventricle global longitudinal strain show wide range values and decreased throughout gestation. Strain values are higher in left ventricle compared to the right one throughout pregnancy. Strain rate values were similar over gestation in each ventricle, but the magnitudes declined overtime in the right and left ventricle. The maturational patterns of left and right strain are gestational specific. With accepted physiological maturation patterns in healthy subjects, these myocardial deformation parameters can provide a valid basis that allows comparison between health and disease.

Preliminary results analysis for left ventricular systolic function in normal fetuses by automated cardiac motion quantitation

BACKGROUND

Fetal heart evaluation has been proven to have the utility in the differential diagnosis of cardiomyopathies or prediction of perinatal mortality in congenital heart disease. The purpose of this study is to introduce a novel method that can measure the global and regional longitudinal strain of left ventricle in fetuses, described as automated cardiac motion quantitation (aCMQ). Furthermore, to evaluate the feasibility and value of aCMQ.

METHODS

A cross-sectional study was conducted in 138 fetuses with normal heart structure, then were divided into four groups by gestational age, standard four-chamber view clips were collected, the global and segmental longitudinal peak systolic strain of the left ventricle were measured by aCMQ, interobserver and intraobserver variability was analyzed.

RESULTS

The success rate of aCMQ analysis was 90.6% (125/138). aCMQ can obtain more comprehensive data to evaluate fetal cardiac function by on-line analysis, including the left ventricular end-systolic volume (LVESV, 0.64 ± 0.16 ml), the left ventricular end-diastolic volume (LVEDV, 0.85 ± 0.35 ml), strain and so on. There was no significant correlation between the gestational age and the global and segmental longitudinal peak strain of the left ventricle (all p > .05). The base and middle segmental strain values of left ventricular free wall were similar to those of the interventricular septum. No significant differences were found in base segments and middle segments for left ventricular free wall (LVLW) and the interventricular septum (IVS) (p > .05). The strain of the apex segment was higher than that of the base and middle segment (p < .05), and there were significant differences between the apex and the base and the middle (p < .05). Interobserver and intraobserver variability showed a small bias among the observers.

CONCLUSIONS

The global and regional strain values of fetus have no correlation with gestational ages, and the strain values of apical segment are higher than those of basal and middle segments. The base and middle segmental strain values of left ventricular free wall were similar to those of the interventricular septum. aCMQ is a novel method of two dimensional speckle tracking echocardiography to assess the global and regional systolic function of fetuses. It's a feasible and reproducible approach to evaluate normal cardiac function of fetus quantitatively and may have potential in fetuses with congenital heart diseases.

Speckle tracking derived reference values of myocardial deformation and impact of cardiovascular risk factors - Results from the population-based STAAB cohort study

AIMS

We aimed to provide reference values for speckle-tracking derived systolic and diastolic myocardial deformation markers, and to determine their relation with age, sex, and cardiovascular risk factors.

METHODS AND RESULTS

The Characteristics and Course of Heart Failure STAges A/B and Determinants of Progression (STAAB) cohort study recruited a representative sample of the population of Würzburg, Germany, aged 30-79 years. In a sample of 1818 participants (52% female, mean age 54±12 years) global longitudinal peak systolic strain (GL-PSS, n = 1218), systolic (GL-SSR, n = 1506), and early (GL-EDSR, n = 1506) and late diastolic strain rates (GL-LDSR, n = 1500) were derived from 2D speckle tracking analysis. From a subgroup of 323 individuals without any cardiovascular risk factor, sex- and age-specific reference values were computed. GL-PSS, GL-SSR, and GL-EDSR were associated with sex, GL-EDSR decreased and GL-LDSR increased with age. In the total sample, dyslipidemia was associated with altered GL-PSS, GL-SSR, and GL-EDSR in women but not in men, whereas obesity was associated with less favorable GL-PSS and GL-EDSR in either sex. Hypertension impacted more adversely on systolic and diastolic myocardial deformation in women compared to men (all p<0.01).

CONCLUSION

The female myocardium appeared more vulnerable to high blood pressure and dyslipidemia when compared to men, while obesity was associated with adverse myocardial deformation in either sex. The reference values for echocardiographic myocardial deformation provided for a non-diseased population and their here reported associations with cardiovascular risk factors will inform future observational and intervention studies regarding i) effect sizes and power calculation, ii) cross-study comparisons, and iii) categorization of myocardial deformation in specific patient groups.

Strain and dyssynchrony in fetuses with congenital heart disease compared to normal controls using speckle tracking echocardiography (STE)

Objective To compare myocardial strain and mechanical dyssynchrony in fetuses with congenital heart disease (CHD) to normal controls using speckle tracking echocardiography (STE). Methods In this comparative cross-sectional study 23 fetuses with CHD and 105 normal controls between 19 and 41 weeks of gestation were assessed with STE. The STE sample box was placed over the myocardium of both ventricles. The parameters of interest included the segmental strain of the left (LV-S) and right lateral ventricle wall (RV-S) and the global ventricular strain of both chambers (2C-S). In order to separately assess the LV, we placed the STE sample box over the myocardium of the LV. We calculated the strain of the LV lateral wall (LW-S), the septum (SEPT-S) and the global ventricular strain of the single LV (1C-S). Furthermore, we analyzed the differences in timing of negative peak myocardial strain between the LV and RV (two-chamber dyssynchrony, 2C-DYS) and also within the LV between the lateral wall and the septum (one-chamber dyssynchrony, 1C-DYS). Results The evaluation of strain and mechanical dyssynchrony was feasible in all cases. Compared to normal controls, fetuses with CHD showed lower segmental and global strain values and the extent of 2C-DYS and 1C-DYS was higher than in the healthy control group. Conclusion The deterioration of myocardial function in CHD can be measured with STE. The assessment of strain and dyssynchrony with STE may be useful for distinguishing fetuses with CHD from healthy fetuses.

A comparative study between transthoracic and transesophageal echo modalities in evaluation of left ventricular deformation

BACKGROUND

2D strain imaging has been proved as an accurate technique for the assessment of left ventricular (LV) function using transthoracic echocardiography (TTE). Transesophageal echocardiography (TEE) has become a standard and essential technique in clinical practice especially when TTE is inconclusive. Adding 2D strain imaging to TEE might be valuable in the evaluation of cardiac performance. The aim of the present study was to compare 2D strain imaging using TTE and TEE in the assessment of left ventricular deformation in patients with cardiovascular diseases.

RESULTS

This study was conducted on sixty patients, who were referred for TEE for various clinical indications. All patients were examined with both TTE and TEE 2D strain imaging. Global and regional strain parameters including longitudinal (LS), circumferential (CS), and radial (RS) were examined. Analysis of 2D strain using TTE was time sparing than TEE (16 ± 1 vs 19 ± 2 min, P < 0.001). From 1020 segments explored using TTE, 97% (LS) and 93% (CS and RS) of the segments were fully analyzed versus 90% and 88% using TEE respectively (P < 0.01). TEE longitudinal strain has an excellent agreement with TTE-derived measurements and a modest agreement in circumferential strain but a notable disparity in radial strain values. Both regional and global LS and RS measured by TTE showed higher values (P < 0.01, < 0.03) compared with its corresponding values measured by TEE. Whereas segmental and global values of CS were higher using TTE modes, the difference with the analogous TEE values did not reach statistical significance. LS and CS measured by TTE and TEE showed excellent but similar correlation with LV EF and wall motion score index.

CONCLUSION

2D strain using TTE is user friendly compared to TEE. However, because of the good agreement, TEE 2D strain might represent an appropriate alternative in the evaluation of global LV deformation.

Speckle tracking quantification of lung sliding for the diagnosis of pneumothorax: a multicentric observational study

PURPOSE

Lung ultrasound is used for the diagnosis of pneumothorax, based on lung sliding abolition which is a qualitative and operator-dependent assessment. Speckle tracking allows the quantification of structure deformation over time by analysing acoustic markers. We aimed to test the ability of speckle tracking technology to quantify lung sliding in a selected cohort of patients and to observe how the technology may help the process of pneumothorax diagnosis.

METHODS

We performed retrospectively a pleural speckle tracking analysis on ultrasound loops from patients with pneumothorax. We compared the values measured by two observers from pneumothorax side with contralateral normal lung side. The receiver operating characteristic (ROC) curve was constructed to evaluate the performance of maximal pleural strain to detect the lung sliding abolition. Diagnosis performance and time to diagnosis between B-Mode and speckle tracking technology were compared from a third blinded observer.

RESULTS

We analysed 104 ultrasound loops from 52 patients. The area under the ROC curve of the maximal pleural strain value to identify lung sliding abolition was 1.00 [95%CI 1.00; 1.00]. Specificity was 100% [95%CI 93%; 100%] and sensitivity was 100% [95%CI 93%; 100%] with the best cut-off of 4%. Over 104 ultrasound loops, the blinded observer made two errors with B-Mode and none with speckle tracking. The median diagnosis time was 3 [2-5] seconds for B-Mode versus 2 [1-2] seconds for speckle tracking (p = 0.001).

CONCLUSION

Speckle tracking technology allows lung sliding quantification and detection of lung sliding abolition in case of pneumothorax on selected ultrasound loops.