Intervendor Variability of Two-Dimensional Strain Using Vendor-Specific and Vendor-Independent Software

Prognostic value of fully-automated left atrial strain in patients with asymptomatic chronic severe aortic regurgitation

BACKGROUND

To examine whether left atrial (LA) strain was associated with adverse outcomes in asymptomatic chronic aortic regurgitation (AR).

METHODS

Asymptomatic patients with ≥moderate-severe AR were retrospectively identified from 2008 through 2022 from a university hospital. Apical 4-chamber left ventricular longitudinal strain (A4C-LVLS), LA reservoir (LASr), conduit (LAScd), and contractile strain (LASct) were measured using fully-automated software. Primary endpoint was all-cause death (ACD); secondary endpoints were heart failure (HF) development or aortic valve surgery (AVS).

RESULTS

Of 352 patients (59 ± 17 years; 19 % female), the mean LV ejection fraction (LVEF) was 60 ± 8 %. The median follow-up during medical surveillance was 4.7 (interquartile range: 1.8-9.0) years; during which 68 patients died. Multivariable analysis adjusted for covariates showed that larger maximal LA volume index (iLAVmax), lower LASr and LASct were independently associated with ACD (all P ≤ 0.047); A4C-LVLS and LAScd were not (P ≥ 0.15). Besides, iLAVmax, LASr, and LASct provided incremental prognostic value over A4C-LVLS in terms of ACD (all P ≤ 0.048). HF symptoms occurred in 126 patients at a median of 2 years. Multivariable determinants for HF development included larger minimal LAV index, lower LASr and LASct (all P ≤ 0.03). Adjusted spline curves showed LASr <38-40 % and LASct <20-24 % were associated with increased risks of ACD and HF development, respectively. Using abovementioned LASr and LASct cutoffs, adjusted Kaplan-Meier curves risk-stratified patients for ACD successfully (P ≤ 0.02). Lower LASr was also independently associated with AVS (Hazard ratio per 1 % increase: 0.98)(P = 0.02).

CONCLUSIONS

In patients with asymptomatic AR, fully-automated LASr and LASct were robust markers for outcome determination; these markers may identify those who need timely surgical referral.

Myocardial strain assessment in the human fetus by cardiac MRI using Doppler ultrasound gating and feature tracking

OBJECTIVES

Assessment of myocardial strain by feature tracking magnetic resonance imaging (FT-MRI) in human fetuses with and without congenital heart disease (CHD) using cardiac Doppler ultrasound (DUS) gating.

METHODS

A total of 43 human fetuses (gestational age 28-41 weeks) underwent dynamic cardiac MRI at 3 T. Cine balanced steady-state free-precession imaging was performed using fetal cardiac DUS gating. FT-MRI was analyzed using dedicated post-processing software. Endo- and epicardial contours were manually delineated from fetal cardiac 4-chamber views, followed by automated propagation to calculate global longitudinal strain (GLS) of the left (LV) and right ventricle (RV), LV radial strain, and LV strain rate.

RESULTS

Strain assessment was successful in 38/43 fetuses (88%); 23 of them had postnatally confirmed diagnosis of CHD (e.g., coarctation, transposition of great arteries) and 15 were heart healthy. Five fetuses were excluded due to reduced image quality. In fetuses with CHD compared to healthy controls, median LV GLS (- 13.2% vs. - 18.9%; p < 0.007), RV GLS (- 7.9% vs. - 16.2%; p < 0.006), and LV strain rate (1.4 s-1 vs. 1.6 s-1; p < 0.003) were significantly higher (i.e., less negative). LV radial strain was without a statistically significant difference (20.7% vs. 22.6%; p = 0.1). Bivariate discriminant analysis for LV GLS and RV GLS revealed a sensitivity of 67% and specificity of 93% to differentiate between fetuses with CHD and healthy fetuses.

CONCLUSION

Myocardial strain was successfully assessed in the human fetus, performing dynamic fetal cardiac MRI with DUS gating. Our study indicates that strain parameters may allow for differentiation between fetuses with and without CHD.

CLINICAL RELEVANCE STATEMENT

Myocardial strain analysis by cardiac MRI with Doppler ultrasound gating and feature tracking may provide a new diagnostic approach for evaluation of fetal cardiac function in congenital heart disease.

KEY POINTS

• MRI myocardial strain analysis has not been performed in human fetuses so far. • Myocardial strain was assessed in human fetuses using cardiac MRI with Doppler ultrasound gating. • MRI myocardial strain may provide a new diagnostic approach to evaluate fetal cardiac function.

A new staging system using right atrial strain in patients with immunoglobulin light-chain cardiac amyloidosis

AIMS

There are minimal data on the prognostic impact of right atrial strain during the reservoir phase (RASr) in patients with immunoglobulin light-chain (AL) cardiac amyloidosis.

METHODS AND RESULTS

Among 78 patients who were diagnosed with AL cardiac amyloidosis at Kumamoto University Hospital from 2007 to 2022, 72 patients with sufficient two-dimensional speckle tracking imaging data without chemotherapy before the diagnosis were retrospectively analysed. During a median follow-up of 403 days, 31 deaths occurred. Age and the rate of male sex were not significantly different between the all-cause death group and the survival group (age, 70.4 ± 8.8 years vs. 67.0 ± 10.0 years, P = 0.14, male sex, 65% vs. 66%, P = 0.91). The estimated glomerular filtration rate (eGFR) was significantly lower, and B-type natriuretic peptide (BNP) and high sensitivity cardiac troponin T (hs-cTnT) were significantly higher, in the all-cause death group versus the survival group (eGFR, 48.2 ± 21.0 mL/min/1.73 m2 vs. 59.4 ± 24.4 mL/min/1.73 m2, P < 0.05, BNP, 725 [360-1312] pg/mL vs. 123 [81-310] pg/mL, P < 0.01, hs-cTnT, 0.12 [0.07-0.18] ng/mL vs. 0.05 [0.03-0.08] ng/mL, P < 0.01). Left ventricular (LV) global longitudinal strain (GLS) (LV-GLS), left atrial strain during the reservoir phase (LASr), right ventricular GLS (RV-GLS), and RASr were significantly lower in the all-cause death group versus the survival group (LV-GLS, 8.5 ± 4.3% vs. 11.8 ± 3.8%, P < 0.01, LASr, 8.8 ± 7.1% vs. 14.3 ± 8.1%, P < 0.01, RV-GLS, 11.6 ± 5.1% vs. 16.4 ± 3.9%, P < 0.01, RASr, 10.2 ± 7.3% vs. 20.7 ± 9.5%, P < 0.01). RASr was significantly associated with all-cause death after adjusting for RV-GLS, LV-GLS and LASr (hazard ratio [HR]: 0.91, 95% confidence interval [95% CI]: 0.83-0.99, P < 0.05). RASr and log-transformed BNP were significantly associated with all-cause death after adjusting for log-transformed troponin T and eGFR (RASr, HR: 0.93, 95% CI: 0.87-1.00, P < 0.05; log-transformed BNP, HR: 2.10, 95% CI: 1.17-3.79, P < 0.05). The optimal cut-off values were RASr: 16.4% (sensitivity: 66%, specificity: 84%, area under curve [AUC]: 0.81) and BNP: 311.2 pg/mL (sensitivity: 83%, specificity: 78%, AUC: 0.82) to predict all-cause mortality using ROC analysis. Kaplan-Meier analysis revealed that patients with low RASr (<16.4%) or high BNP (>311.2 pg/mL) had a significantly high probability of all-cause death (both, P < 0.01). We devised a new staging score by adding 1 point if RASr decreased or BNP levels increased more than each cut-off value. The HR for all-cause death using score 0 as a reference was 5.95 (95% CI: 1.19-29.79; P < 0.05) for score 1 and 23.29 (95% CI: 5.37-100.98; P < 0.01) for score 2.

CONCLUSIONS

The new staging system using RASr and BNP predicted prognosis in patients with AL cardiac amyloidosis.

A prospective randomized controlled trial to determine the safety and efficacy of extracorporeal shock waves therapy for primary prevention of subclinical cardiotoxicity in breast cancer patients without a cardiovascular risk treated with doxorubicin

Background

Doxorubicin is a highly effective anti-cancer drug that causes left ventricular (LV) dysfunction and induces late-onset cardiomyopathy. However, an effective and clinically applicable preventive treatment is yet to be discovered.

Objective

Cardiac-Extracorporeal shockwave therapy (C-ESWT) has been suggested to treat inflammatory and ischemic diseases and protect cardiomyocytes from doxorubicin-induced cardiomyopathy. This study aims to assess the safety and efficacy of C-ESWT in the prevention of subclinical cardiotoxicity.

Methods

We enrolled 64 breast cancer patients. C-ESWT group 33 patients were treated with our C-ESWT (200 shots/spot at 0.09 mJ/mm2 for 20 spots, 3 times every six weeks). The efficacy endpoints were the difference in left ventricular global longitudinal strain (LVGLS) change by 2D speckle tracking echocardiography and chemotherapy-related cardiac dysfunction (CTRCD). Echocardiography was performed on the baseline line and every 4 cycles of chemotherapy, followed by a follow-up 3,6 months after chemotherapy to compare the incidence of cardiomyopathy of subclinical LV dysfunction due to chemotherapy between the two groups.

Results

Participants averaged 50 ± 9 years in age, 100% female. In the results of follow-up 6 months after the end of chemotherapy, there was a significant difference in delta LVGLS between the C-ESWT group and the control group (LVGLS; -1.1 ± 10.9% vs. -11.5 ± 11.6% p-value; <0.001). A total of 23% (15 patients) of patients developed CTRCD (Control group; 13 vs. C-ESWT group; (2). C-ESWT was performed safely without any serious adverse events.

Conclusion

In this prospective study, C-ESWT established efficacy in preventing subclinical cardiotoxicity, especially in breast cancer patients using doxorubicin chemotherapy, and the safety of C-ESWT.

Clinical Trial Registration

ClinicalTrials.gov, identifier (NCT05584163).

Incremental Value of Global Longitudinal Strain for Confirming Heart Failure-Related Symptoms in Severe Aortic Stenosis

The indications or timing of aortic valve replacement for symptomatic aortic stenosis (AS) are based on a patient's life expectancy and symptoms. However, clinical decision-making may be difficult because symptoms are subjective and cannot be quantitatively assessed and confirmed. This study aimed to evaluate the association between heart failure (HF)-related symptoms and cardiac hemodynamic left ventricular deformations in patients with severe AS using transthoracic echocardiographic assessments of left ventricular global longitudinal strain (LV-GLS). The medical records of patients hospitalized for AS between February 2017 and September 2019 were retrospectively screened. Independent cardiologists analyzed the transthoracic echocardiographic images of a digital echocardiography database. The cohort comprised 177 hospitalized patients with severe AS and no history of HF. The subgroup with HF-related symptoms included 87 patients, whereas that without HF-related symptoms included 90 patients. In 145 patients without atrial fibrillation, the left atrial volume index (LAVI) and LV-GLS were significantly associated with HF-related symptoms (odds ratio 1.033, 95% confidence interval 1.008 to 1.059, p = 0.011 and odds ratio 1.224, 95% confidence interval 1.118 to 1.340, p <0.0001, respectively). Moreover, the combination of brain natriuretic peptide level, LAVI, and LV-GLS showed better diagnostic accuracy than the combination of brain natriuretic peptide level and LAVI (p = 0.005). However, there were no such tendencies in 32 patients with atrial fibrillation. The HF-related symptoms in patients with severe AS were strongly linked to LV-GLS. LV-GLS showed incremental value for confirming HF-related symptoms.

Influence of ultrasound transmit frequency on measurement of global longitudinal strain on 2D speckle tracking echocardiography

The reproducibility of longitudinal strain measured by 2D speckle tracking echocardiography (2DSTE) may be affected by ultrasound settings. This study investigated the effect of transmit ultrasound frequency on global longitudinal strain (GLS) by 2DSTE. Apical, 2- and 4-chamber, and long-axis views were obtained in consecutive 162 patients using Philips ultrasound devices. Three different frequency presets were used sequentially: high resolution (HRES, 1.9 to 2.1 MHz), general (HGEN, 1.6 to 1.8 MHz), and penetration mode (HPEN, 1.3 to 1.6 MHz). GLS values were determined for each preset using the Philips Q-station software, resulting in GLS-HRES, GLS-HGEN, and GLS-HPEN. Among the 151 patients with successfully measured GLS, a significant difference in GLS was observed among the three presets (p < 0.0001). GLS-HRES (- 17.9 ± 4.4%) showed a slightly smaller magnitude compared to GLS-HGEN (- 18.8 ± 4.5%, p < 0.0001) and GLS-HPEN (- 18.8 ± 4.5%, p < 0.0001), with absolute differences of 1.1 ± 1.0% and 1.1 ± 1.2%, respectively. This variation in GLS with frequency was evident in patients with both optimal (n = 104) and suboptimal (n = 47) image quality and remained consistent regardless of ultrasound devices, ischemic etiology, or ejection fraction. In conclusion, ultrasound frequency had only a modest effect on GLS measurements. GLS may be reliably assessed in most cases regardless of the ultrasound frequency used.

Tales from the future-nuclear cardio-oncology, from prediction to diagnosis and monitoring

Cancer and cardiovascular diseases (CVD) often share common risk factors, and patients with CVD who develop cancer are at high risk of experiencing major adverse cardiovascular events. Additionally, cancer treatment can induce short- and long-term adverse cardiovascular events. Given the improvement in oncological patients' prognosis, the burden in this vulnerable population is slowly shifting towards increased cardiovascular mortality. Consequently, the field of cardio-oncology is steadily expanding, prompting the need for new markers to stratify and monitor the cardiovascular risk in oncological patients before, during, and after the completion of treatment. Advanced non-invasive cardiac imaging has raised great interest in the early detection of CVD and cardiotoxicity in oncological patients. Nuclear medicine has long been a pivotal exam to robustly assess and monitor the cardiac function of patients undergoing potentially cardiotoxic chemotherapies. In addition, recent radiotracers have shown great interest in the early detection of cancer-treatment-related cardiotoxicity. In this review, we summarize the current and emerging nuclear cardiology tools that can help identify cardiotoxicity and assess the cardiovascular risk in patients undergoing cancer treatments and discuss the specific role of nuclear cardiology alongside other non-invasive imaging techniques.

Using 2D speckle-tracking echocardiography to localize the accessory pathway and evaluate cardiac function and dyssynchrony in pediatric patients with Wolf-Parkinson-White syndrome

Wolf-Parkinson-White (WPW) accessory pathway (AP) may be associated with reentry supraventricular tachycardia (SVT) in addition to ventricular dyssynchrony and cardiac dysfunction. Electrophysiological studies (EPS) are the gold standard for the localization of the AP; however, 2D speckle-tracking echocardiography (2D-STE) may help in the localization of the AP noninvasively. Our study aims to evaluate the capability of 2D-STE for AP localization and the identification of AP-related contractile abnormalities and dyssynchrony in pediatric patients with WPW syndrome. This prospective multicenter cohort study involved 18 pediatric patients with ventricular preexcitation from January 2021 to January 2023. Tissue Doppler imaging (TDI), conventional echocardiography, and 2D-STE were done. Myocardial velocities, myocardial performance index (MPI), the global and segmental longitudinal strain of the left ventricle (LV), and time-to-peak longitudinal strain (TPLS) were measured before and after ablation. The longitudinal strain of the LV segments supplied by the AP, or the nearby segments close to the AP, was significantly impaired and improved after ablation (P = 0.0001). The abnormal strain pattern in the affected segments could predict the location of the AP. The TPLS of the affected segments significantly increased after ablation (P = 0.0001), denoting improved dyssynchrony. The ejection time and the LV MPI measured at the basal septum improved significantly after ablation.

CONCLUSIONS

2D STE may be used for noninvasive localization of the AP and to evaluate cardiac function and dyssynchrony in patients with WPW. Further research on more patients is necessary to validate this method for AP localization.

WHAT IS KNOWN

• Accessory pathways (AP) associated with the Wolf-Parkinson-White (WPW) syndrome have been linked to supraventricular tachycardia (SVT). Even without SVT, WPW can cause left ventricular dyssynchrony, contractile dysfunction, and cardiomyopathy. • Electrophysiology study is the gold standard for the localization of the AP in WPW syndrome.

WHAT IS NEW

• The combination of 2D-speckle-tracking echocardiography (2D-STE) and the modified Arruda algorithm can precisely localize the AP associated with WPW syndrome. • 2D-STE can potentially assess cardiac function and dyssynchrony related to WPW syndrome. Additionally, 2D-STE can be utilized to evaluate the effectiveness of ablation in restoring cardiac function and dyssynchrony.

Right ventricular free wall longitudinal strain assessment using offline speckle tracking in COVID-19 patients requiring intensive medical care

PURPOSE

The purpose of this study was to evaluate and confirm the prognostic utility of comprehensive transthoracic echocardiography (TTE) using offline myocardial strain analyses in a Japanese coronavirus disease (COVID-19) cohort hospitalized in intensive care units.

METHODS

We performed a retrospective analysis of 90 consecutive adult patients with COVID-19 who underwent clinically indicated standard two-dimensional TTE in intensive care wards. Patients on extracorporeal membrane oxygenation (ECMO) at the time of TTE were excluded. Biventricular strain assessments using vendor-independent offline speckle tracking analysis were performed. Patients with inadequate TTE image quality were also excluded.

RESULTS

Among the 90 COVID-19 patients, 15 (17%) patients required venovenous or venoarterial ECMO. There were 25 (28%) in-hospital deaths. A composite event, defined as the combination of in-hospital mortality and subsequent initiation of ECMO, occurred in 32 patients. Multivariate logistic regression for composite events indicated that right ventricular free wall longitudinal strain (RV-FWLS) and mechanical ventilation at the time of TTE were independent risk factors for composite events (p = 0.01, odds ratio [OR] 1.09, 95% confidence interval [CI] 1.01-1.18; p = 0.04, OR 3.24, 95% CI 1.03-10.20). Cumulative survival probability plots generated using the Kaplan-Meier method for composite events with log-rank tests revealed a significant difference between subgroups divided by the cutoff value of RV-FWLS (p < 0.001).

CONCLUSION

Offline measurement of RV-FWLS may be a potent predictor of worse outcomes in COVID-19 requiring intensive care. Larger multicenter prospective studies are needed.

Echocardiographic score for the screening of cardiac amyloidosis with positive 99m technetium pyrophosphate scintigraphy result

INTRODUCTION

Speckle-tracking-derived strains in cardiac chambers may provide better solutions for transthyretin amyloid cardiomyopathy (ATTR-CM) screening. This study aimed to evaluate the efficacy of biventricular strain measurements using speckle tracking for screening ^99m Tc-pyrophosphate (^99m Tc-PYP) scintigraphy-positive cardiomyopathy, which is nearly equivalent to ATTR-CM.

METHODS

We performed a retrospective analysis of transthoracic echocardiographic studies using vendor-independent speckle tracking analysis in older patients (≥65 years) who underwent ^99m Tc-PYP scintigraphy to evaluate the etiology of suspected ATTR-CM in our institute between January 2019 and December 2022.

RESULTS

The entire cohort (n = 89) was divided into two subgroups positive ^99m Tc-PYP scan results (n = 34) and negative ^99m Tc-PYP scan results (n = 55). In the multivariate analysis, posterior wall thickness (p = .003, odds ratio [OR]:1.48, 95% confidence interval [CI]:1.14 -1.92), left ventricular longitudinal strain apical/basal ratio (LVLSapi/bas) (p = .015, OR: 2.78, 95% CI: 1.23-6.32, and right ventricular longitudinal strain (RVLS) (p = .003, OR: 1.15, 95% CI: 1.05 -1.26) were selected to be the most representative echocardiographic findings in ^99m Tc-PYP positive cardiomyopathy. The receiver operating characteristic analysis indicated that posterior wall thickness (p < .0001, area under the curve [AUC]: .821, cut-off value: 14.0 mm), LVLSapi/bas (p < .001, AUC: .802, cut-off value: 2,16), and RVLS (p < .001, AUC: .791, cut-off value: -18.7%) could significantly detect ^99m Tc-PYP positive results with an excellent credibility. Echocardiographic score points calculated using the summary of these three parameters in each patient revealed that a 2-point score had a fair sensitivity (85%) and an excellent specificity (93%), while a 1-point score had an excellent sensitivity (91%) and a modest specificity (53%).

CONCLUSION

Our proposed echocardiographic screening tool for ^99m Tc-PYP scintigraphy-positive cardiomyopathy may help clinicians manage patients with suspected ATTR-CM.

Prognostic value of right ventricular global longitudinal strain in patients with immunoglobulin light-chain cardiac amyloidosis

Aims

Left ventricular (LV) global longitudinal strain (GLS) (LV-GLS) is a strong and independent predictor of outcomes in patients with immunoglobulin light-chain (AL) cardiac amyloidosis. This study was performed to investigate whether right ventricular (RV) GLS (RV-GLS) provides prognostic information in patients with AL amyloidosis.

Methods and results

Among 74 patients who were diagnosed with AL cardiac amyloidosis at Kumamoto University Hospital from December 2005 to December 2022, 65 patients who had enough information for two-dimensional speckle tracking imaging and did not receive chemotherapy before the diagnosis of cardiac amyloidosis were retrospectively analysed. During a median follow-up of 359 days, 29 deaths occurred. In two-dimensional echocardiographic findings, LV-GLS, left atrium reservoir strain (LASr), and RV-GLS were significantly lower in the all-cause death group than in the survival group (LV-GLS: 8.9 ± 4.2 vs. 11.7 ± 3.9, P < 0.01; LASr: 9.06 ± 7.28 vs. 14.09 ± 8.32, P < 0.05; RV-GLS: 12.0 ± 5.1 vs. 16.8 ± 4.0, P < 0.01). Multivariable Cox proportional hazard analysis showed RV-GLS was significantly and independently associated with all-cause death in patients with AL cardiac amyloidosis (hazard ratio 0.85; 95% confidence interval, 0.77-0.94; P < 0.01). Receiver operating characteristic analysis showed that the area under the curve of RV-GLS for all-cause death was 0.774 and that the best cut-off value of RV-GLS was 14.5% (sensitivity, 75%; specificity, 72%). In the Kaplan-Meier analysis, patients with AL cardiac amyloidosis who had low RV-GLS (<14.5%) had a significantly higher probability of all-cause death (P < 0.01).

Conclusion

RV-GLS has prognostic value in patients with AL cardiac amyloidosis and provides greater prognostic power than LV-GLS and LASr.

Connection between Cardiac Fibrosis Biomarkers and Echocardiography Parameters in Advanced Chronic Kidney Disease Patients

BACKGROUND

Myocardial fibrosis represents a mainstay pathway in the pathophysiology of uremic cardiomyopathy. This process leads to structural and functional changes in the heart, which can be detected by echocardiography. The purpose of our study was to determine the association between four echocardiographic parameters (ejection fraction (EF), global longitudinal strain (GLS), mean E/e' ratio, and left atrial volume indexed) and biomarkers associated with cardiac fibrosis, such as procollagen type I carboxy-terminal propeptide (PICP), procollagen type III N-terminal peptide (P3NP), and galectin-3 (Gal-3) in patients with end-stage renal disease (ESRD).

METHODS

140 patients with ESRD were enrolled and investigated by echocardiography and the serum levels of the aforementioned biomarkers were determined at baseline.

RESULTS

The mean EF was 53.63 ± 8%, the mean GLS was -10.2 ± 5.3%, the mean E/e' ratio was 9.8 ± 4.3, and the mean left atrial volume indexed (LAVI) was 45.8 ± 14.2 mL/m². The average levels for PICP, P3NP, and Gal-3 were 457.2 ± 240 µg/L, 242 ± 199.9 µg/L, and 10.7 ± 3.7 ng/mL, respectively. In regression analysis, PICP was strongly associated with all four echocardiographic parameters (EF: p = 0.0002, R² = 0.69; GLS: p = 0.00001, R² = 0.81; mean E/e': p = 0.00002; R² = 0.89; LAVI: p = 0.003; R² = 0.73). P3NP and Gal-3 were only associated with the EF (p = 0.01, R² = 0.31 and p = 0.02; R² = 0.35, respectively).

CONCLUSION

Our study evidenced that PICP, a collagen-derived biomarker, is associated with important echocardiography parameters, suggesting that it can serve as an indicator of the presence of subclinical systolic and diastolic dysfunction in patients with advanced CKD.

Sacubitril/Valsartan Improves Left Atrial and Ventricular Strain and Strain Rate in Patients with Heart Failure with Reduced Ejection Fraction

BACKGROUND

Data on the impact of sacubitril/valsartan (SV) therapy on phasic left atrial (LA) and left ventricular (LV) strain in heart failure with reduced ejection fraction (HFrEF) are limited. The aim of this study was to evaluate changes in two-dimensional speckle tracking (2D-STE) parameters with SV therapy in HFrEF patients.

METHODS

Prospective evaluation of HFrEF patients receiving optimized medical therapy. Two-dimensional speckle tracking (2D-STE) parameters were assessed at baseline and after 6 months of SV therapy. LA strain and strain rate (SR) in reservoir, conduit, and contraction phases were compared with LV longitudinal, radial, and circumferential strain and SR and stratified according to heart rhythm and HFrEF etiology.

RESULTS

A total of 35 patients completed the 6-month follow-up, with a mean age of 59 ± 11 years, 40% in atrial fibrillation, 43% with ischemic etiology, and LVEF of 29 ± 6%. There were significant improvements in LA reservoir, conduit, and contractile strain and SR following SV therapy, particularly among patients in sinus rhythm. There were significant improvements in longitudinal, radial, and circumferential LV function indices.

CONCLUSION

SV therapy in HFrEF was associated with improved longitudinal, radial, and circumferential function, particularly among patients in sinus rhythm. These findings can provide insights into the mechanisms underlying the improvement of cardiac function and help assess subclinical responses to the treatment.

Developing an Echocardiography-Based, Automatic Deep Learning Framework for the Differentiation of Increased Left Ventricular Wall Thickness Etiologies

AIMS

Increased left ventricular (LV) wall thickness is frequently encountered in transthoracic echocardiography (TTE). While accurate and early diagnosis is clinically important, given the differences in available therapeutic options and prognosis, an extensive workup is often required to establish the diagnosis. We propose the first echo-based, automated deep learning model with a fusion architecture to facilitate the evaluation and diagnosis of increased left ventricular (LV) wall thickness.

METHODS AND RESULTS

Patients with an established diagnosis of increased LV wall thickness (hypertrophic cardiomyopathy (HCM), cardiac amyloidosis (CA), and hypertensive heart disease (HTN)/others) between 1/2015 and 11/2019 at Mayo Clinic Arizona were identified. The cohort was divided into 80%/10%/10% for training, validation, and testing sets, respectively. Six baseline TTE views were used to optimize a pre-trained InceptionResnetV2 model. Each model output was used to train a meta-learner under a fusion architecture. Model performance was assessed by multiclass area under the receiver operating characteristic curve (AUROC). A total of 586 patients were used for the final analysis (194 HCM, 201 CA, and 191 HTN/others). The mean age was 55.0 years, and 57.8% were male. Among the individual view-dependent models, the apical 4-chamber model had the best performance (AUROC: HCM: 0.94, CA: 0.73, and HTN/other: 0.87). The final fusion model outperformed all the view-dependent models (AUROC: HCM: 0.93, CA: 0.90, and HTN/other: 0.92).

CONCLUSION

The echo-based InceptionResnetV2 fusion model can accurately classify the main etiologies of increased LV wall thickness and can facilitate the process of diagnosis and workup.

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.

Abnormal echocardiographic findings after COVID-19 infection: a multicenter registry

The Coronavirus Disease 2019 (COVID-19) pandemic has transformed health systems worldwide. There is conflicting data regarding the degree of cardiovascular involvement following infection. A registry was designed to evaluate the prevalence of echocardiographic abnormalities in adults recovered from COVID-19. We prospectively evaluated 595 participants (mean age 45.5 ± 14.9 years; 50.8% female) from 10 institutions in Argentina and Brazil. Median time between infection and evaluation was two months, and 82.5% of participants were not hospitalized for their infection. Echocardiographic studies were conducted with General Electric equipment; 2DE imaging and global longitudinal strain (GLS) of both ventricles were performed. A total of 61.7% of the participants denied relevant cardiovascular history and 41.8% had prolonged symptoms after resolution of COVID-19 infection. Mean left ventricular ejection fraction (LVEF) was 61.0 ± 5.5% overall. In patients without prior comorbidities, 8.2% had some echocardiographic abnormality: 5.7% had reduced GLS, 3.0% had a LVEF below normal range, and 1.1% had wall motion abnormalities. The right ventricle (RV) was dilated in 1.6% of participants, 3.1% had a reduced GLS, and 0.27% had reduced RV function. Mild pericardial effusion was observed in 0.82% of participants. Male patients were more likely to have new echocardiographic abnormalities (OR 2.82, p = 0.002). Time elapsed since infection resolution (p = 0.245), presence of symptoms (p = 0.927), or history of hospitalization during infection (p = 0.671) did not have any correlation with echocardiographic abnormalities. Cardiovascular abnormalities after COVID-19 infection are rare and usually mild, especially following mild infection, being a low GLS of left and right ventricle, the most common ones in our registry. Post COVID cardiac abnormalities may be more frequent among males.

Vendor independent myocardial strain values in children

BACKGROUND

Two-dimensional (2D) strain imaging has become an important tool in assessing subclinical myocardial dysfunction in children. However, there are no published normal values for vendor-independent strain software. The aim of this study was to estimate 2D strain values in a cohort of healthy children using Tomtec cardiac performance analysis (CPA), a vendor-independent software.

METHODS

Transthoracic echocardiograms of healthy pediatric outpatients (0-18 years) were retrospectively analyzed from the Vanderbilt Pediatric Heart Institute using CPA. The cardiac assessment included global longitudinal strain (GLS), global longitudinal strain rate (GLSR), global circumferential strain (GCS), and global circumferential strain rate (GCSR). Mean strain values with standard deviation (SD) are reported. The Wilcoxon rank sum test, linear regression, and one-way analysis of variance were used to assess differences among the various groups.

RESULTS

Among 142 children analyzed, 79 (56%) were male, and the median age was 5.5 (range, 0-18) years. The mean (SD) strain values were GLS -19.3 ± 3.4, GLSR -1.1 ± .22; GCS -24.7 ± 4.3, GCSR -1.5 ± .28. Age accounted for <8% of the variation in GLS, GCS, and GCSR. However, for GLSR, there was a statistically significant difference between younger and older age groups with higher GLSR in the younger age group. Age accounted for ∼25% of the variation in GLSR (R2  = .25, p < 0.001). There were no significant differences in strain based on sex.

CONCLUSION

We report normal myocardial strain values in healthy children by age for strain using CPA. These values add to the growing body of literature on myocardial strain in children and provide necessary data for the interpretation of strain imaging.

Reference centiles for left ventricular longitudinal global and regional systolic strain by automated functional imaging in healthy Egyptian children

BACKGROUND

Two-dimensional speckle tracking echocardiography-derived left ventricular longitudinal systolic strain is an important myocardial deformation parameter for assessing the systolic function of the left ventricle. Strain values differ according to the vendor machine and software. This study aimed to provide normal reference values for global and regional left ventricular longitudinal systolic strain in Egyptian children using automated functional imaging software integrated into the General Electric healthcare machine and to study the correlation between the global longitudinal left ventricular systolic strain and age, body size, vital data, and some echocardiographic parameters.

METHODS

Healthy children (250) aged from 1 to 16 years were included. Conventional echocardiography was done to measure the left ventricular dimensions and function. Automated functional imaging was performed to measure the global and regional peak longitudinal systolic strain.

RESULTS

The global longitudinal strain was -21.224 ± 1.862%. The regional strain was -20.68 ± 2.11%, -21.06 ± 1.84%, and -21.86 ± 2.71% at the basal, mid, and apical segments, respectively. The mean values of the systolic longitudinal strain become significantly more negative from base to apex. Age differences were found as regard to global and regional longitudinal strain parameters but no gender differences. The global peak longitudinal systolic strain correlated positively with age. No correlations were found with either the anthropometric parameters or the vital data.

CONCLUSIONS

Age-specific normal values for two-dimensional speckle tracking-derived left ventricular longitudinal regional and global systolic strain are established using automated functional imaging.

Agreement of two vendor-independent strain analysis software platforms in assessing left ventricular global longitudinal strain

PURPOSE

The new version of EchoPAC platform was recently developed by General Electronics (GE) to provide 'vendor-independent' full-myocardial-layer left ventricular (LV) global longitudinal strain (LV-GLS). The agreement of the LV-GLS by two vendor-independent software platforms was investigated under diverse clinical situations.

METHODS

Two-dimensional speckle-tracking LV-GLS was separately measured by two software platforms. LV-GLS values were compared as default setting of each software platform (GE full-myocardial-layer [GE-Full], and TomTec endocardial-layer [TomTec-Endo]). Agreements according to various conditions and type of echocardiography vendors were evaluated using Bland-Altman analysis and intraclass correlation coefficients (ICC). Inter-observer reproducibility of each software platform was assessed, and agreements were further evaluated in various subgroups.

RESULTS

One hundred five subjects were initial candidates for the current study (normal LV function without any cardiac pathology [n = 25], hypertrophic cardiomyopathy [n = 40], dilated cardiomyopathy [n = 25], or restrictive cardiomyopathy [n = 15]). After excluding seven subjects with inadequate tracking quality, 98 subjects were finally analyzed. The average LV-GLS was lower in GE-Full than in TomTec-Endo. Agreement between GE-Full and TomTec-Endo was excellent in general; while the greatest bias was observed in the hypertrophic cardiomyopathy group, with TomTec-Endo exhibiting greater LV-GLS values than GE-Full (bias -1.71, limits of agreement -6.02 to 2.59). Both platforms showed excellent inter-observer reproducibility (GE-Full, ICC 0.99; TomTec-Endo, ICC 0.91), and were in good agreements regardless of the echocardiography vendors or subgroups according to age, heart rate, myocardial wall thickness, or LV ejection fraction.

CONCLUSIONS

LV-GLS by GE-Full showed excellent agreement with that by TomTec-Endo under various cardiac conditions.

Post-systolic shortening index by echocardiography evaluation of dyssynchrony in the non-dilated and hypertrophied left ventricle

Background

Post-systolic shortening index (PSI) is defined as myocardial shortening that occurs after aortic valve closure, and is an emerging measure of regional LV contractile dysfunction. PSI measurement variability amongst software vendor and its relationship with mechanical dyssynchrony and mechanical dispersion index (MDI) remains unknown. We evaluated PSI by speckle-tracking echocardiography from several vendors in patients with increased left ventricular wall thickness, and associations with MDI.

Methods

This is a prospective cross-sectional study of 70 patients (36 hypertrophic cardiomyopathy [HCM], 18 cardiac amyloidosis and 16 healthy controls) undergoing clinically indicated echocardiography. PSI was measured using QLAB/aCMQ (Philips), QLAB/LV auto-trace (Philips), EchoPAC (GE), Velocity Vector Imaging (Siemens), and EchoInsight (EPSILON) software packages, and calculated as 100%×(post systolic strain–end-systole strain)/post systolic strain.

Results

There was a significant difference in mean PSI among controls 2.1±0.6%, HCM 6.1±2.6% and cardiac amyloidosis 6.8±2.7% (p <0.001). Variations between software vendors were significant in patients with pathologic increases in LV wall thickness (for HCM p = 0.03, for amyloidosis p = 0.008), but not in controls (p = 0.11). Furthermore, there were moderate correlations between PSI and both MDI (r = 0.77) and left ventricular global longitudinal strain (r = 0.69).

Conclusion

PSI was greater in HCM and cardiac amyloidosis patients than controls, and a valuable tool for dyssynchrony evaluation, with moderate correlations to MDI and strain. However, there were significant variations in PSI measurements by software vendor especially in patients with pathological increase in LV wall thickness, suggesting that separate vendor-specific thresholds for abnormal PSI are required.

Left Ventricular Strain Analysis During Submaximal Semisupine Bicycle Exercise Stress Echocardiography in Childhood Cancer Survivors

Background

Childhood cancer survivors (CCSs) show relevant cardiac morbidity and mortality throughout life. Early detection is key for optimal support of patients at risk. The aim of this study was to evaluate 2‐dimensional speckle‐tracking echocardiography strain analysis during semisupine exercise stress in CCSs for detection of subclinical left ventricular dysfunction after cancer treatment.

Methods and Results

Seventy‐seven CCSs ≥1‐year postchemotherapy were prospectively examined at rest, low, and submaximal stress level and compared with a cohort of healthy adolescents and young adults (n=50). Global longitudinal strain (GLS), short axis circumferential strain, and corresponding strain rates were analyzed using vendor‐independent software. CCSs at median 7.8 years postchemotherapy showed comparable left ventricular GLS, circumferential strain, and strain rate values at all stress stages to healthy controls. Yet, prevalence of abnormal GLS (defined as <2 SD of controls reference) in CCSs was 1.3% at rest, 2.7% at low, and 8.6% at submaximal stress. In CCSs, relative change of circumferential strain from rest to submaximal stress was lower than in healthy controls, median 16.9 (interquartile range [IQR], 3.4; 28.8) % versus 23.3 (IQR, 11.3; 33.3) %, P=0.03, most apparent in the subgroups of CCSs after high‐dose anthracycline treatment and cancer diagnosis before the age of 5 years.

Conclusions

In this prospective 2‐dimensional speckle tracking echocardiography strain study, prevalence of abnormal left ventricular GLS increased with stress level reflecting impaired cardiac adaptation to exercise stress in some CCSs. However, relatively early after last chemotherapy, this did not result in significant differences of mean GLS‐, circumferential strain‐, and strain rate values between CCSs and controls at any stress level.

The value of myocardial work in assessment of ventricular function in patients with non-obstructive hypertrophic cardiomyopathy

Background

To evaluate myocardial work using speckle tracking echocardiography in patients with non-obstructive hypertrophic cardiomyopathy (HCM).

Methods

Fifty patients with HCM and 50 normal controls were included. Left ventricular ejection fraction (LVEF) was quantified using the bi-plane Simpson’s method. Myocardial work parameters, which included global work index (GWI), global constructive work (GCW), global waste work (GWW), and global work efficiency (GWE), were derived from the 2D strain-pressure loop.

Results

The patient group was older (49.19 ± 14.69 vs. 37.16 ± 7.49 years old) and had a higher body mass index (24.93 ± 3.67 vs. 23.26 ± 3.32 kg/m²) and systolic blood pressure (121.81 ± 16.50 vs. 115.30 ± 11.01 mmHg) (P < 0.05). The mean LVEF in patients was 51%, with 54% of patients had LVEF ≤ 50%. Compared to controls, GWI (946.42 ± 360.64 vs. 1639.72 ± 204.56 mmHg%), GCW (1176.94 ± 373.23 vs. 1960.16 ± 255.72 mmHg%), and GWE (83.96 ± 7.68 vs. 95.26 ± 1.98%) were significantly decreased, while GWW (158.17 ± 82.47 vs. 79.12 ± 40.26 mmHg%) was significantly increased (P < 0.05) in the patient group. In patients, GWE showed a trend of positive correlation with LVEF (r = 0.276, P = 0.06), while GWW had a trend of negative correlation with LVEF (r = − 0.241, P = 0.09). No correlation between myocardial work and LV diastolic function or QRS duration was observed. Maximal wall thickness significantly correlated with all the myocardial work parameters.

Conclusions

Assessing myocardial work adds useful information of LV function in patients with non-obstructive HCM.

Utility of left atrial and ventricular strain for diagnosis of transthyretin amyloid cardiomyopathy in aortic stenosis

Aims

To clarify the usefulness of left atrial (LA) function and left ventricular (LV) function obtained by two‐dimensional (2D) speckle tracking echocardiography to diagnose concomitant transthyretin amyloid cardiomyopathy (ATTR‐CM) in patients with aortic stenosis (AS).

Methods and results

We analysed 72 consecutive patients with moderate to severe AS who underwent ^99mTc‐pyrophosphate (PYP) scintigraphy at Kumamoto University Hospital from January 2012 to September 2020. We divided these 72 patients into 2 groups based on their ^99mTc‐PYP scintigraphy positivity or negativity. Among 72 patients, 16 patients (22%) were positive, and 56 patients (78%) were negative for ^99mTc‐PYP scintigraphy. In clinical baseline characteristics, natural logarithm troponin T was significantly higher in the ^99mTc‐PYP scintigraphy‐positive than scintigraphy‐negative group (−2.9 ± 0.5 vs. −3.5 ± 0.8 ng/mL, P < 0.05). In conventional echocardiography, the severity of AS was not significantly different between these two groups. In 2D speckle tracking echocardiography, the relative apical longitudinal strain (LS) index (RapLSI) [apical LS/ (basal LS + mid LS)] was significantly higher (1.09 ± 0.49 vs. 0.78 ± 0.23, P < 0.05) and the peak longitudinal strain rate (LSR) in LA was significantly lower in the ^99mTc‐PYP scintigraphy‐positive than scintigraphy‐negative group (0.36 ± 0.14 vs. 0.55 ± 0.20 s⁻¹, P < 0.05). Multivariable logistic analysis revealed the peak LSR in LA and RapLSI were significantly associated with ^99mTc‐PYP scintigraphy positivity. Receiver operating characteristic analysis showed that the area under the curve (AUC) of the peak LSR in LA for ^99mTc‐PYP scintigraphy positivity was 0.79 and that the best cut‐off value of the peak LSR in LA was 0.47 s⁻¹ (sensitivity: 78.6% and specificity: 72.3%). The AUC of RapLSI for ^99mTc‐PYP scintigraphy positivity was 0.69, and the cut‐off value of RapLSI was decided as 1.00 (sensitivity: 43.8% and specificity: 87.5%) according to the previous report. The ^99mTc‐PYP scintigraphy positivity in patients with RapLSI ≥ 1.0 and the peak LSR in LA ≤ 0.47 s⁻¹ was 83.3% (5/6), and the ^99mTc‐PYP scintigraphy negativity in patients with RapLSI < 1.0 and the peak LSR in LA > 0.47 s⁻¹ was 96.6% (28/29).

Conclusions

Left atrial and LV strain analysis were significantly associated with ^99mTc‐PYP scintigraphy positivity in ATTR‐CM patients with moderate to severe AS. The combination of the peak LSR in LA and RapLSI might be a useful predictor of the presence of ATTR‐CM in patients with moderate to severe AS.

Malignant Mitral Valve Prolapse: Risk and Prevention of Sudden Cardiac Death

Purpose of review

The purpose of this review is to explore the prevalence and risk factors for a malignant phenotype in mitral valve prolapse (MVP) characterized by life-threatening ventricular arrhythmias and sudden cardiac arrest and death (SCD), including mechanistic and pathophysiologic findings and mechanism-based potential therapies.

Recent findings

A malignant phenotype in MVP characterized by life-threatening arrhythmias has long been recognized, although MVP is often benign. Efforts to identify this malignant phenotype have revealed potential risk factors for SCD that include elongated, myxomatous leaflets, ECG changes and complex ventricular ectopy. More recently, malignant MVP has been associated with myocardial fibrosis in the papillary muscles and inferobasal left ventricular wall. This localization suggests a central role of prolapse-induced mechanical forces on the myocardium in creating an arrhythmogenic substrate and triggering life-threatening arrhythmias. This mechanism for fibrosis is also consistent with imaging evidence of prolapse-induced mechanical changes in the papillary muscles and inferobasal left ventricular wall. Currently, no therapy to prevent SCD in malignant MVP has been established and limited clinical data are available. Mechanistic information and prospective study have the potential to identify patients at risk of SCD and preventive strategies.

Summary

Malignant MVP relates to unique properties and mechanical abnormalities in the mitral valve apparatus and adjacent myocardium. Increased understanding of disease mechanisms and determinants of arrhythmias is needed to establish effective therapies.

The roles of global longitudinal strain imaging in contemporary clinical cardiology

Myocardial deformation imaging is now readily available during routine echocardiography and plays an important role in the advanced care of cardiovascular diseases. Its clinical value in detecting subtle myocardial dysfunction, by helping diagnose disease and allowing prediction of disease progression and earlier pharmacological intervention, has been demonstrated. Strain imaging has been the most studied and clinically used technique in the field of cardio-oncology. A relative percent reduction in left ventricular (LV) global longitudinal strain > 15% from baseline is considered a marker of early subclinical LV dysfunction and may have the potential to guide early initiation of cardioprotective therapy. The role of strain imaging is expanding to other fields, such as cardiac amyloidosis, other cardiomyopathies, valvular heart diseases, pulmonary hypertension, and heart failure with preserved ejection fraction. It is also used for the evaluation of the right ventricle and atria. This review aims to provide a current understanding of the roles of strain imaging in the evaluation and management of patients with cardiovascular diseases in clinical practice.

Longitudinal Assessment of Global and Regional Left Ventricular Strain in Patients with Multisystem Inflammatory Syndrome in Children (MIS-C)

Multisystem inflammatory syndrome in children (MIS-C) is one of the most significant sequela of coronavirus disease 2019 (COVID-19) in children. Emerging literature has described myocardial dysfunction in MIS-C patients using traditional and two-dimensional speckle tracking echocardiography in the acute phase. However, data regarding persistence of subclinical myocardial injury after recovery is limited. We aimed to detect these changes with deformation imaging, hypothesizing that left ventricular global longitudinal (GLS) and circumferential strain (GCS) would remain impaired in the chronic phase despite normalization of ventricular function parameters assessed by two-dimensional echocardiography. A retrospective, single-institution review of 22 patients with MIS-C was performed. Fractional shortening, GLS, and GCS, along with regional longitudinal (RLS) and circumferential strain (RCS) were compared across the acute, subacute, and chronic timepoints (presentation, 14-42, and > 42 days, respectively). Mean GLS improved from - 18.4% in the acute phase to - 20.1% in the chronic phase (p = 0.4). Mean GCS improved from - 19.4% in the acute phase to - 23.5% in the chronic phase (p = 0.03). RCS and RLS were impaired in the acute phase and showed a trend towards recovery by the chronic phase, with the exception of the basal anterolateral segment. In our longitudinal study of MIS-C patients, GLS and GCS were lower in the acute phase, corroborating with left ventricular dysfunction by traditional measures. Additionally, as function globally recovers, GLS and GCS also normalize. However, some regional segments continue to have decreased strain values which may be an important subclinical marker for future adverse events.

Pediatric Cardio-Oncology Medicine: A New Approach in Cardiovascular Care

Survival for pediatric patients diagnosed with cancer has improved significantly. This achievement has been made possible due to new treatment modalities and the incorporation of a systematic multidisciplinary approach for supportive care. Understanding the distinctive cardiovascular characteristics of children undergoing cancer therapies has set the underpinnings to provide comprehensive care before, during, and after the management of cancer. Nonetheless, we acknowledge the challenge to understand the rapid expansion of oncology disciplines. The limited guidelines in pediatric cardio-oncology have motivated us to develop risk-stratification systems to institute surveillance and therapeutic support for this patient population. Here, we describe a collaborative approach to provide wide-ranging cardiovascular care to children and young adults with oncology diseases. Promoting collaboration in pediatric cardio-oncology medicine will ultimately provide excellent quality of care for future generations of patients.

Impact of inter-vendor variability on evaluation of left ventricular mechanical dispersion

PURPOSE

Left ventricular mechanical dispersion (LVMD) is a novel speckle tracking parameter for prognostic assessment of arrhythmic risk prediction. There is growing evidence to support its use in a variety of cardiomyopathic processes. There is paucity of data addressing any presence of inter-vendor discrepancies for LVMD. The aim of this study was to assess inter-vendor variability of LVMD in vendor specific software (VSS) and vendor independent software (VIS) in subjects with preserved and reduced left ventricular function.

METHODS

Fifty-nine subjects (14 normal subjects and 45 subjects with cardiac disease) were recruited and 2D speckle tracking echocardiographic images were acquired on two different ultrasound machines (GE and Philips). LVMD was measured by two different VSS (EchoPac GE and QLAB Philips) and one VIS (TomTec Arena).

RESULTS

There was significant bias and wide limits of agreement (LOA) in the overall cohort observed between two different VSS (17.6 ms; LOA: -29.6 to 64.8; r: .47). There was acceptable bias and narrower LOA with good agreement for LVMD between images obtained on different vendors when performed on VIS (-3.1 ms; LOA: -27.6 to 21.4; r: .75). QLAB LVMD was consistently higher than GE LVMD and TomTec LVMD in both preserved and reduced left ventricular function. LVMD measurements have high intra-vendor reproducibility with excellent inter and intra-observer agreement.

CONCLUSIONS

There was acceptable bias and narrower LOA for LVMD assessment on a VIS. Inter-vendor variability exists for LVMD assessment between VSS. Serial measurements of LVMD should be performed using a single vendor for consistent and reliable results.

Advantage and validation of vendor-independent software for myocardial strain analysis compared to vendor-specific software

Introduction

One of the main limitations incorporating strain imaging into widespread clinical practice is inter-vendor incompatibility. This poses a problem when serial strain measurements are required in a multi-vendor echocardiography laboratory.

Methods

This study sought to compare the variability of two-dimensional speckle-tracking global and regional longitudinal strain using vendor-specific software and vendor-independent software from images acquired by two different commercially available ultrasound systems. Forty subjects underwent two sequential echocardiographic acquisitions using different ultrasound systems (GE Vivid E9 and Philips iE33). Global longitudinal strain and regional peak longitudinal strain were derived using vendor-specific software (EchoPAC BT 13 v201 and QLAB version 10.3) and vendor-independent software (TomTec Image Arena version 4.6). Agreement and reproducibility of global and regional strain between vendor-specific and vendor-independent software were assessed by independent blinded observers.

Results

Global longitudinal strain derived from vendor-independent software was comparable to global longitudinal strain derived from vendor-specific software, whilst regional strain was lower in agreement compared to global longitudinal strain. There was good overall agreement and high inter- and intra-observer reproducibility using vendor-independent software for global longitudinal strain and regional strain.

Conclusions

Vendor-independent software provides good agreement with vendor-specific software for global longitudinal strain. However, minor variability exists for regional strain measurements between vendor-independent and vendor-specific software. Good agreement of strain measurements derived by vendor-independent software suggests vendor-independent software could potentially be useful for serial follow-up of global longitudinal strain.

Prognostic value of left atrial strain in patients with wild-type transthyretin amyloid cardiomyopathy

Aims

This study was performed to investigate whether left atrial (LA) strain by echocardiography provides prognostic information in patients with wild‐type transthyretin amyloid cardiomyopathy (ATTRwt‐CM).

Methods and results

Among 129 patients who were diagnosed with ATTRwt‐CM at Kumamoto University Hospital from December 2002 to December 2019, 113 patients who had enough information for two‐dimensional speckle tracking echocardiography were enrolled in this study. During a median follow‐up of 668 days, 28 cardiovascular deaths occurred. Compared with patients in the non‐event group, those in the cardiovascular death group were significantly older (81.5 ± 7.4 vs. 78.1 ± 6.1 years, P < 0.01), had a lower incidence of carpal tunnel syndrome (21% vs. 47%, P < 0.05), and had a higher high‐sensitivity cardiac troponin T [0.085 (0.063–0.105) vs. 0.049 (0.036–0.079) ng/mL, P < 0.01] and B‐type natriuretic peptide concentrations [419 (239–541) vs. 271 (155–462) pg/mL, P < 0.01] and lower estimated glomerular filtration rate (41.8 ± 15.4 vs. 53.4 ± 14.6 mL/min/1.73 m², P < 0.01). Electrocardiography showed higher rate of a V1–V3 QS pattern (52% vs. 24%, P < 0.01) and complete left bundle branch block (27% vs. 6%, P < 0.01), and echocardiography showed a significantly lower peak LA strain rate during the contraction phase (0.16 ± 0.13 vs. 0.28 ± 0.27 S⁻¹, P < 0.05), LA strain during the reservoir phase (LASr) (5.84 ± 2.41 vs. 8.22 ± 4.05%, P < 0.01), and peak LA strain rate during the reservoir phase (0.26 ± 0.09 vs. 0.33 ± 0.15 S⁻¹, P < 0.05) in the cardiovascular death group than in non‐event group. By contrast, conventional echocardiographic findings were not significantly different between these two groups. After adjusting for conventional predictive factors of ATTRwt‐CM (age, high‐sensitivity cardiac troponin T and B‐type natriuretic peptide concentrations, and estimated glomerular filtration rate), multivariable Cox proportional hazard analyses showed that LASr was significantly and independently associated with cardiovascular death in patients with ATTRwt‐CM (odds ratio, 0.84; 95% confidence interval, 0.72–0.98; P < 0.05). After adjusting for age and echocardiographic findings associated with cardiovascular death (LA volume index and peak LA strain rate during the contraction phase), LASr was significantly and independently associated with cardiovascular death in patients with ATTRwt‐CM (odds ratio, 0.83; 95% confidence interval, 0.70–0.98; P < 0.05). Receiver operating characteristic curve analysis showed that the area under the curve of LASr for cardiovascular death was 0.686 and that the best cut‐off value of LASr was 6.69% (sensitivity, 62.4%; specificity, 64.3%). In the Kaplan–Meier analysis, patients with low LASr (<6.69%) had a significantly higher probability of total cardiovascular death (P < 0.05) and heart failure‐related hospitalization (P < 0.05).

Conclusions

Left atrial strain during the reservoir phase provides significant prognostic value in patients with ATTRwt‐CM even after adjusting for conventional predictive factors.

Global longitudinal strain in heart transplantation recipients using different vendors: reliability and validity in a tertiary hospital in Colombia

Global Longitudinal Strain (GLS) is a useful tool to follow-up heart transplant (HT) recipients. Important inter-vendor variability of GLS measurements has been reported in healthy subjects and different conditions, but there is still limited evidence among HT patients. We assessed the reliability and validity of GLS using two vendors (General Electric and Philips) in a group of consecutive and stable adult HT recipients. Patients underwent two concurrent GLS analyses during their echocardiographic follow-up. We evaluated GLS inter-vendor reliability using Bland-Altman's limits of agreement (LOA) plots, computing its coverage probability (CP) and the intraclass correlation coefficient (ICC). Validity was assessed though receiver operating characteristics (ROC) curves, predictive values, sensitivity and specificity of GLS for each vendor to detect a normal left ventricle function. 78 pairs of GLS studies in 53 stable HT patients were analyzed. We observed a modest inter-vendor reliability with a broad LOA (less than 50% of values falling out our CP of 2% and an ICC of 0.49). ROC analyses (areas under the curve of 0.824 Vs. 0.631, p < 0.05) and diagnosis test indices (Sensitivity of 0.73 Vs. 0.64; and Specificity of 0.79 Vs. 0.50) favored GE over Philips. Inter-vendor variability for GLS analysis exceeded clinically acceptable limits in HT recipients. GLS from GE software seemed to show higher validity as compared to Philips'. The present study provides evidence to consider caution for the interpretation of GLS for clinical management in the follow-up of HT patients, especially when GLS is measured by different vendors.

Inter-observer and Inter-vendor Variability in Strain Measurements in Patients with Single Right Ventricular Anatomy

Myocardial strain offers new insights into ventricular performance, There are software packages from several different companies used to ascertain this, and little data is available in patients with single right ventricle (sRV) physiology. We aimed to compare the analysis of two strain software applications using a cohort of patients with sRV for both inter-vendor and inter-observer variability. Echocardiograms from 85 patients with sRV (122 separate studies) were prospectively evaluated. All had Glenn and/or Fontan palliation. Longitudinal 4-chamber (4LS), inflow/outflow (IO), circumferential, and radial strain were assessed using Velocity Vector Imaging (VVI, Seimens, Munich) and Automated Functional Imaging (AFI, General Electric, Boston) software. In a subset of 45 patients (61 separate studies), strain measurements were obtained by two sonographers so a paired "inter-observer" analysis could be performed. A moderate correlation between measurements made by the two systems was observed. Circumferential strain assessment had the highest R value (0.77) with all others having R values < 0.6. Both software packages showed modest inter-observer reproducibility for longitudinal and circumferential strain. VVI intraclass correlation coefficients (ICC) for 4LS and average circumferential strain (ACS) were 0.6 and 0.58, compared to 0.68 and 0.59 for AFI. Other than radial strain and VVI IO inferior strain, mean strain differences between AFI and VVI were ≤ 1%. Inter-observer variability is modest, however, mean differences are minimal suggesting reasonable clinical reliability. Inter-vendor variability is greater and not as clinically reliable. In patients with sRV, serial assessments with strain should be performed using the same software.

Duration of early systolic lengthening: prognostic potential in the general population

BACKGROUND

When the left ventricle pressure rises during early systole, myocardial fibres with reduced contractility tend to stretch instead of shortening. This interval is known as duration of early systolic lengthening (DESL). We sought to investigate if DESL provides prognostic information on cardiovascular events.

METHODS AND RESULTS

In this prospective study we included 1210 participants from a low-risk general population who underwent speckle tracking echocardiography (men 41%, mean age 56 years, SD 16). Primary endpoints were incident heart failure (HF), myocardial infarction (MI), and cardiovascular death (CVD). We defined DESL as time from onset of Q-wave on the electrocardiogram to peak positive systolic strain. In addition, we assessed the ratio between DESL and duration of cardiac systole, DESLsystole.During median follow-up of 16 years, 90 (7%) developed HF, 50 (4%) MI, and 70 (6%) experienced CVD. Both DESL [hazard ratio (HR) 1.58 95%CI 1.16-2.15, P = 0.004 per 10 ms increase] and DESLsystole (HR 1.74 95%CI 1.24-2.47, P = 0.001 per 1% increase) were predictors of HF. Similarly, DESL (HR 1.40 95%CI 1.09-1.78, P = 0.007 per 10 ms increase) and DESLsystole (HR 1.58 95%CI 1.01-2.49, P = 0.047 per 1% increase) were predictors of MI. No associations were found with CVD. After adjusting for clinical and echocardiographic parameters, the associations remained significant. DESLsystole was superior to systolic echocardiographic parameters for predicting HF (P = 0.012).

CONCLUSION

DESL and the novel index of DESLsystole provide independent and novel prognostic information on the risk of HF and MI in the general population. Evaluation of DESL should be explored in future echocardiographic studies.

Artificial Intelligence for Automatic Measurement of Left Ventricular Strain in Echocardiography

OBJECTIVES

This study sought to examine if fully automated measurements of global longitudinal strain (GLS) using a novel motion estimation technology based on deep learning and artificial intelligence (AI) are feasible and comparable with a conventional speckle-tracking application.

BACKGROUND

GLS is an important parameter when evaluating left ventricular function. However, analyses of GLS are time consuming and demand expertise, and thus are underused in clinical practice.

METHODS

In this study, 200 patients with a wide range of left ventricle (LV) function were included. Three standard apical cine-loops were analyzed using the AI pipeline. The AI method measured GLS and was compared with a commercially available semiautomatic speckle-tracking software (EchoPAC v202, GE Healthcare, Chicago, Illinois).

RESULTS

The AI method succeeded to both correctly classify all 3 standard apical views and perform timing of cardiac events in 89% of patients. Furthermore, the method successfully performed automatic segmentation, motion estimates, and measurements of GLS in all examinations, across different cardiac pathologies and throughout the spectrum of LV function. GLS was -12.0 ± 4.1% for the AI method and -13.5 ± 5.3% for the reference method. Bias was -1.4 ± 0.3% (95% limits of agreement: 2.3 to -5.1), which is comparable with intervendor studies. The AI method eliminated measurement variability and a complete GLS analysis was processed within 15 s.

CONCLUSIONS

Through the range of LV function this novel AI method succeeds, without any operator input, to automatically identify the 3 standard apical views, perform timing of cardiac events, trace the myocardium, perform motion estimation, and measure GLS. Fully automated measurements based on AI could facilitate the clinical implementation of GLS.

Echocardiography protocol for early detection of cardiac dysfunction in childhood cancer survivors in the multicenter DCCSS LATER 2 CARD study: Design, feasibility, and reproducibility

BACKGROUND

Cardiotoxicity is a well-known side effect after anthracyclines and chest radiotherapy in childhood cancer survivors (CCS). The DCCSS LATER 2 CARD (cardiology) study includes evaluation of echocardiographic measurements for early identification of CCS at highest risk of developing heart failure. This paper describes the design, feasibility, and reproducibility of the echocardiography protocol.

METHODS

Echocardiograms from CCS and sibling controls were prospectively obtained at the participating centers and centrally analyzed. We describe the image acquisition, measurement protocol, and software-specific considerations for myocardial strain analyses. We report the feasibility of the primary outcomes of systolic and diastolic function, as well as reproducibility analyses in 30 subjects.

RESULTS

We obtained 1,679 echocardiograms. Biplane ejection fraction (LVEF) measurement was feasible in 91% and 96% of CCS and siblings, respectively, global longitudinal strain (GLS) in 80% and 91%, global circumferential strain (GCS) in 86% and 89%, and ≥2 diastolic function parameters in 99% and 100%, right ventricle free wall strain (RVFWS) in 57% and 65%, and left atrial reservoir strain (LASr) in 72% and 79%. Intra-class correlation coefficients for inter-observer variability were 0.85 for LVEF, 0.76 for GLS, 0.70 for GCS, 0.89 for RVFWS and 0.89 for LASr. Intra-class correlation coefficients for intra-observer variability were 0.87 for LVEF, 0.82 for GLS, 0.82 for GCS, 0.85 for RVFWS and 0.79 for LASr.

CONCLUSION

The DCCSS LATER 2 CARD study includes a protocolized echocardiogram, with feasible and reproducible primary outcome measurements. This ensures high-quality outcome data for prevalence estimates and for reliable comparison of cardiac function parameters.

Multivendor comparison of global and regional 2D cardiovascular magnetic resonance feature tracking strains vs tissue tagging at 3T

BACKGROUND

Cardiovascular magnetic resonance (CMR) 2D feature tracking (FT) left ventricular (LV) myocardial strain has seen widespread use to characterize myocardial deformation. Yet, validation of CMR FT measurements remains scarce, particularly for regional strain. Therefore, we aimed to perform intervendor comparison of 3 different FT software against tagging.

METHODS

In 61 subjects (18 healthy subjects, 18 patients with chronic myocardial infarction, 15 with dilated cardiomyopathy, and 10 with LV hypertrophy due to hypertrophic cardiomyopathy or aortic stenosis) were prospectively compared global (G) and regional transmural peak-systolic Lagrangian longitudinal (LS), circumferential (CS) and radial strains (RS) by 3 FT software (cvi42, Segment, and Tomtec) among each other and with tagging at 3T. We also evaluated the ability of regional LS, CS, and RS by different FT software vs tagging to identify late gadolinium enhancement (LGE) in the 18 infarct patients.

RESULTS

GLS and GCS by all 3 software had an excellent agreement among each other (ICC = 0.94-0.98 for GLS and ICC = 0.96-0.98 for GCS respectively) and against tagging (ICC = 0.92-0.94 for GLS and ICC = 0.88-0.91 for GCS respectively), while GRS showed inconsistent agreement between vendors (ICC 0.10-0.81). For regional LS, the agreement was good (ICC = 0.68) between 2 vendors but less vs the 3rd (ICC 0.50-0.59) and moderate to poor (ICC 0.44-0.47) between all three FT software and tagging. Also, for regional CS agreement between 2 software was higher (ICC = 0.80) than against the 3rd (ICC = 0.58-0.60), and both better agreed with tagging (ICC = 0.70-0.72) than the 3rd (ICC = 0.57). Regional RS had more variation in the agreement between methods ranging from good (ICC = 0.75) to poor (ICC = 0.05). Finally, the accuracy of scar detection by regional strains differed among the 3 FT software. While the accuracy of regional LS was similar, CS by one software was less accurate (AUC 0.68) than tagging (AUC 0.80, p < 0.006) and RS less accurate (AUC 0.578) than the other two (AUC 0.76 and 0.73, p < 0.02) to discriminate segments with LGE.

CONCLUSIONS

We confirm good agreement of CMR FT and little intervendor difference for GLS and GCS evaluation, with variable agreement for GRS. For regional strain evaluation, intervendor difference was larger, especially for RS, and the diagnostic performance varied more substantially among different vendors for regional strain analysis.

Elevated high-sensitivity troponin is associated with subclinical cardiac dysfunction in patients recovered from coronavirus disease 2019

The aim of this study is to investigate myocardial damage in recovering coronavirus disease 2019 (COVID-19) patients with high-sensitivity troponin levels (hsTnT) and echocardiography. In this single-center cohort study, 215 COVID-19 recovered patients were recruited from all over Japan between April and September 2020. Demographic characteristics, hsTnT levels, and echocardiography data were collected for 209 patients, after excluding those without serum samples or good-quality echocardiographic images. The mean (± standard deviation) age was 44 (± 12) years (range: 36-55 years), and 50.7% of the patients were males. The median time interval (interquartile range) from COVID-19 onset to post-recovery examination was 56 days (34-96 days). Seventy-four recovered patients (35.4%) had hsTnT less than detection sensitivity (< 3 pg/mL) and 135 recovered patients (64.6%) had hsTnT ≥ 3 pg/mL. Ejection fraction was more than 50% in all cases. Left ventricular global longitudinal strain (LVGLS) and right ventricular free-wall longitudinal strain (RVFWLS) were reduced in 62 (29.7%) and 8 patients (3.8%), respectively. They were significantly associated with elevated hsTnT levels. In cases with hsTnT above 5 pg/mL, the LVGLS was greatly reduced to 19.0 ± 2.2% (p < 0.001). Multivariate linear regression analysis showed that elevated hsTnT level was an independent predictor of reduced LVGLS (standardized β = -0.34; p < 0.001). In recovered COVID-19 patients, even a slight increase in hsTnT above detection sensitivity was associated with decreased LVGLS. hsTnT and echocardiography may be useful tools to detect myocardial injury in recovered COVID-19 patients.

Non-invasive left ventricular myocardial work indices in healthy adolescents at rest

Global myocardial work (GMW) provides a metric of left ventricular (LV) function and energy consumption. Its non-invasive assessment by echocardiography correlates with invasive measures and normal values have been reported in healthy adults. We aimed to establish normal values in a healthy adolescent population. Fifty-two healthy adolescents (mean age = 14.5 ± 2.0 years, range 11-19 years, 62% male) with normal echocardiograms were included. Brachial cuff blood pressure was obtained immediately following apical imaging in the supine position. Post-processing of echocardiograms for speckle tracking strain measurement and derivation of global myocardial work indices from LV pressure-strain loops was performed. The mean global work index (GWI) was 1802.0 ± 264.4 mmHg% with mean global work efficiency of 95.5 ± 1.1%. The mean global constructive work (GCW) was 2054.5 ± 297.3 mmHg%, and the mean global wasted work 83.8 ± 28.1 mmHg%. On multivariable analysis, there were significant associations between both GWI and GCW with systolic blood pressure (β coefficient = 0.57, p < 0.001; β coefficient = 0.67, p < 0.001 respectively) and LV global longitudinal strain (GLS) (β coefficient = - 0.56, p < 0.001; β coefficient = - 0.52, p < 0.001 respectively). There were no associations with any of the work indices with age, sex, body surface area, heart rate or LV ejection fraction. This study provides echocardiographic reference ranges for non-invasive indices of GMW in normal adolescents.

The strain and strain rate imaging paradox in echocardiography: overabundant literature in the last two decades but still uncertain clinical utility in an individual case

Almost two decades ago strain and strain rate imaging were proposed as a new, potentially more sensitive modality for quantifying both regional and global myocardial function. Until now, however, strain and strain rate imaging have been slow to be incorporated into everyday clinical practice. More recently, two dimensional strain has been claimed as of greater clinical utility, given that it is angle independent, with improved feasibility and reproducibility as compared to tissue Doppler strain. Nevertheless, speckle tracking strain is reliant on 2D image quality and frame rates. Three dimensional speckle tracking could eliminate the problem of through-plane motion inherent in 2D imaging, but 3D strain is currently limited by low frame rates. Another limitation of strain imaging is that the results are dependent on the ultrasound machine on which analyses are performed, with variability in measurements between different vendors. Despite the diagnostic and prognostic advantages of 2D strain, there is a lack of specific therapeutic interventions based on strain and a paucity of long-term large-scale randomized trial evidence on cardiovascular outcomes. After overabundant literature the same definition of normal cut-off values is controversial and not univocal. Further studies are needed, involving both manufacturers and medical professionals, on the additive contribution, possibly different case by case, of interfering and artifactual factors, aside from myocardial function per se. These artifactual determinants and motion artifacts components could be dominant in individual cases and should always be taken into account in the clinical decision making process in a single case.

The influence of training status on right ventricular morphology and segmental strain in elite pre-adolescent soccer players

Cardiac modifications to training are a product of the genetic pre-disposition for adaptation and the repetitive haemodynamic loads that are placed on the myocardium. Elite pre-adolescent athletes are exposed to high-intensity training at a young age with little understanding of the physiological and clinical consequences. It is unclear how right ventricular (RV) structure and function may respond to this type of stimulus. The aim of this study was to compare RV structure and strain across the cardiac cycle and within individual segments in elite soccer players (SP) and controls (CON).

METHODS

Twenty-two highly trained, male pre-adolescent SP and 22 age-and sex-matched recreationally active individuals CON were investigated using 2D echocardiography, including myocardial speckle tracking to assess basal, mid-wall, apical and global longitudinal strain and strain rate during systole (SRS) and diastole (SRE and SRA).

RESULTS

greater RV cavity size was identified in the SP compared to CON (RVD₁ SP: 32.3 ± 3.1 vs. CON: 29.6 ± 2.8 (mm/m²)^0.5; p = 0.005). No inter-group differences were noted for peak global RV strain (SP: - 28.6 ± 4.9 vs CON: - 30.3 ± 4.0%, p = 0.11). Lower mid-wall strain was demonstrated in the SP compared to CON (SP: - 27.9 ± 5.8 vs. CON: - 32.2 ± 4.4%, p = 0.007).

CONCLUSION

Soccer training has the potential to increase RV size in pre-adolescent players. The unique segmental analyses used in this study have identified inter-group differences that were masked by global strain evaluations. The clinical and physiological implications of these findings warrant further investigation.

Echocardiographic myocardial strain analysis describes subclinical cardiac dysfunction after craniospinal irradiation in pediatric and young adult patients with central nervous system tumors

Background

Craniospinal irradiation (CSI) is part of the treatment of central nervous system (CNS) tumors and is associated with cardiovascular disease in adults. Global myocardial strain analysis including longitudinal peak systolic strain (GLS), circumferential peak systolic strain (GCS), and radial peak systolic strain (GRS) can reveal subclinical cardiac dysfunction.

Methods

Retrospective, single-center study in patients managed with CSI vs. age-matched controls. Clinical data and echocardiography, including myocardial strain analysis, were collected at early (< 12 months) and late (≥ 12 months) time points after completion of CSI.

Results

Echocardiograms were available at 20 early and 34 late time points. Patients at the late time point were older (21.7 ± 10.4 vs. 13.3 ± 9.6 years) and further out from CSI (13.1 ± 8.8 vs. 0.2 ± 0.3 years). Standard echocardiographic parameters were normal for both groups. For early, CSI vs. control: GLS was − 16.8 ± 3.6% vs. -21.3 ± 4.0% (p = 0.0002), GCS was − 22.5 ± 5.2% vs. -21.3 ± 3.4% (p = 0.28), and GRS was 21.8 ± 11.0% vs. 26.9 ± 7.7% (p = 0.07). For late, CSI vs. control: GLS was − 16.2 ± 5.4% vs. -21.6 ± 3.7% (p < 0.0001), GCS was − 20.9 ± 6.8% vs. -21.9 ± 3.5% (p = 0.42), and GRS was 22.5 ± 10.0% vs. 27.3 ± 8.3% (p = 0.03). Radiation type (proton vs. photon), and radiation dose (< 30 Gy vs. ≥ 30 Gy) did not impact any parameter, although numbers were small.

Conclusions

Subclinical cardiac systolic dysfunction by GLS is present both early and late after CSI. These results argue for future studies to determine baseline cardiovascular status and the need for early initiation of longitudinal follow-up post CSI.

Inter-vendor variability in strain measurements depends on software rather than image characteristics

Despite standardization efforts, vendors still use specific proprietary software algorithms for echocardiographic strain measurements, which result in high inter-vendor variability. Using vendor-independent software could be one solution. Little is known, however, how vendor specific image characteristics can influence tracking results of such software. We therefore investigated the reproducibility, accuracy, and scar detection ability of strain measurements on images from different vendors by using a vendor-independent software. A vendor-independent software (TomTec Image Arena) was used to analyse datasets of 63 patients which were obtained on machines from four different ultrasound machine vendors (GE, Philips, Siemens, Toshiba). We measured the tracking feasibility, inter-vendor bias, the relative test-re-test variability and scar discrimination ability of strain measurements. Cardiac magnetic resonance delayed enhancement images were used as the reference standard of scar definition. Tracking feasibility on vendor datasets were significantly different (p < 0.001). Variability of global longitudinal strain (GLS) measurements was similar among the vendors whereas variability of segmental longitudinal strain (SLS) showed modest difference. Relative test-re-test variability of GLS and SLS showed no relevant differences. No significant difference in scar detection capability was observed. Average GLS and SLS values were similar among vendors. Reproducibility of GLS measurements showed no difference among vendors and was in acceptable range. SLS reproducibility was high but similar for all vendors. No relevant difference was found for identifying regional dysfunction. Tracking feasibility showed a substantial difference among images from different vendors. Our findings demonstrate that tracking results depend mainly on the software used and show little influence from vendor specific image characteristics.

Inter-vendor variability and reproducibility of subcostal left ventricular longitudinal strain

Left ventricular longitudinal strain (LVLS) performed using subcostal windows is a novel alternative for patients who require strain imaging but have poor apical windows. We investigated the reproducibility and inter-vendor variability of subcostal LVLS. One hundred and twenty-four echocardiographic studies were analysed from 73 women with early stage HER2-positive breast cancer. Speckle tracking strain was performed offline using EchoPAC and TomTec on subcostal 4-chamber and 3-chamber views to obtain subcostal 4-chamber (SC4_LS) and 3-chamber (SC3_LS) LVLS which was then averaged (SCav_LS). Reproducibility of subcostal single chamber and averaged LVLS were assessed. Measurements between platforms were compared. Strain was reported in absolute magnitude. EchoPAC measurements of SC3_LS (20.5 ± 2.4% vs. 21.2 ± 2.5%, p = 0.002) and SCav_LS (20.9 ± 2.1% vs. 21.2 ± 2.1%, p = 0.02) were lower than TomTec measurements while SC4_LS was similar (21.3 ± 2.7% vs. 21.3 ± 2.5%, p = 0.94). Mean differences between EchoPAC and TomTec were ≤ 0.6% strain units for all subcostal LVLS measurements; SCav_LS showed the narrowest limits of agreement (LOA) (mean difference - 0.3%, LOA - 3.2 to 2.6%). EchoPAC and TomTec measurements of SCav_LS showed good correlation (r = 0.76, p < 0.001). Intra-observer and inter-observer analysis showed good reproducibility. Inter-observer variability was lower than inter-vendor variability; SCav_LS was most reproducible: inter-observer relative mean error was 3.6% for EchoPAC and 4.3% for TomTec and inter-observer LOA were ± 2.1% for EchoPAC and ± 2.6% for TomTec. Averaged subcostal LVLS was highly reproducible with inter-observer variability comparable to GLS. Inter-vendor differences in averaged subcostal LVLS were small but statistically significant.

The Role of Speckle Strain Echocardiography in the Diagnosis of Early Subclinical Cardiac Injury in Cancer Patients-Is There More Than Just Left Ventricle Global Longitudinal Strain?

With the improvement in survival rate, cardiotoxicity has emerged as a significant adverse effect of cancer therapy. Early diagnosis of subclinical cardiac injury may allow the initiation of cardioprotective therapy and preventing the interruption of optimal cancer therapy and the development of irreversible cardiac dysfunction. In this article, we review the role of two-dimensional speckle tracking echocardiography (2D-STE), beyond the common left ventricle global longitudinal strain in the diagnosis of early subclinical cardiac injury in patients treated with cancer therapies.

Artificial Intelligence Aids Cardiac Image Quality Assessment for Improving Precision in Strain Measurements

OBJECTIVES

The aim of this study was to develop an artificial intelligence tool to assess echocardiographic image quality objectively.

BACKGROUND

Left ventricular global longitudinal strain (LVGLS) has recently been used to monitor cancer therapeutics-related cardiac dysfunction (CTRCD) but image quality limits its reliability.

METHODS

A DenseNet-121 convolutional neural network was developed for view identification from an athlete's echocardiographic dataset. To prove the concept that classification confidence (CC) can serve as a quality marker, values of longitudinal strain derived from feature tracking of cardiac magnetic resonance (CMR) imaging and strain analysis of echocardiography were compared. The CC was then applied to patients with breast cancer free from CTRCD to investigate the effects of image quality on the reliability of strain analysis.

RESULTS

CC of the apical 4-chamber view (A4C) was significantly correlated with the endocardial border delineation index. CC of A4C >900 significantly predicted a <15% relative difference in longitudinal strain between CMR feature tracking and automated echocardiographic analysis. Echocardiographic studies (n =752) of 102 patients with breast cancer without CTRCD were investigated. The strain analysis showed higher parallel forms, inter-rater, and test-retest reliabilities in patients with CC of A4C >900. During sequential comparisons of automated LVGLS in individual patients, those with CC of A4C >900 had a lower false positive detection rate of CTRCD.

CONCLUSIONS

CC of A4C was associated with the reliability of automated LVGLS and could also potentially be used as a filter to select comparable images from sequential echocardiographic studies in individual patients and reduce the false positive detection rate of CTRCD.