Transcatheter aortic valve implantation impact on left ventricular myocardial damage: long term follow-up

INTRODUCTION

Aortic stenosis (AS) is causing myocardial damages and replacement is mainly indicated based on symptoms. Non-invasive estimation of myocardial work (MW) provide a less afterload dependent tool that, we sought to look at the impact of transcatheter aortic valve implantation (TAVI) on the myocardium at long-term follow-up and according to current indications.

METHODS

We conducted an observational, cross-sectional, single-center study. Patients were selected based on the validated indication for a TAVI. Standardized echocardiographies were repeated.

RESULTS

102 patients were included. Mean age was 85-year-old, 45% were female, 68% get high-blood pressure and 52% had a coronary disease. One fifth was suffering from low-flow low-gradient aortic stenosis. Follow-up was performed at 22 ± 9.5 months after the TAVI. No TAVI-dysfunction was observed. LVEF was stable (62 ± 8%), and global longitudinal strain get improved (-14.0% ± 3.7 vs -16.0% ± 3.6, p-value <0.0001). No improvement of the MW-parameters was noticed (Global Work Index (LV GWI) 2099 ± 692mmHg% vs 2066 ± 706mmHg%, p=0.8, Global Constructive (LV GCW) 2463 ± 736mmHg% vs 2463 ± 676mmHg%, p=0.8). Global Wasted Work increased (214 [149; 357] mmHg% vs 247 [177; 394] mmHg%, p= 0.0008).

CONCLUSION

In a population of severe symptomatic AS-patients who had undergone a TAVI, the non-invasive myocardial indices that assess the LV performance at long term follow-up did not improve. These results are questioning the timing of the intervention and the need for a more attention in the pharmacological management of these AS-patients.

Comparison of left ventricular deformation abnormalities by echocardiography with cardiac magnetic resonance imaging in patients with acute myocarditis and preserved left ventricular ejection fraction

Purpose

Cardiac magnetic resonance imaging (cMRI) represents the gold standard to detect myocarditis. Left ventricular (LV) deformation imaging provides additional diagnostic options presumably exceeding conventional transthoracic echocardiography (TTE). The present study aimed to analyze the feasibility to detect myocarditis in patients (pts) with preserved LV ejection fraction (LVEF) by TTE compared to cMRI. It has been hypothesized that the number of pathological findings by deformation imaging correspond to findings in cMRI.

Methods and results

Between January 2018 and February 2020 102 pts with acute myocarditis according to the modified Lake Louise criteria and early gadolinium enhancement (EGE) by cMRI were identified at the department of cardiology at the University Hospital Leipzig. Twenty-six pts were included in this retrospective comparative study based on specific selection criteria. Twelve pts with normal cMRI served as a control group. LV deformation was analyzed by global and regional longitudinal strain (GLS, rLS), global and regional circumferential and radial strain (GCS, rCS, GRS, rRS), and LV rotation (including layer strain analysis). All parameters were compared to findings of edema, inflammation, and fibrosis by cMRI according to Lake Louise criteria. All pts with acute myocarditis diagnosed by cMRI showed pathological findings in TTE. Especially rCS and LV rotation analyzed by regional layer strain exhibit a high concordance with pathological findings in cMRI. In controls no LV deformation abnormalities were documented. Mean values of GLS, GRS, and GCS were not significantly different between pts with acute myocarditis and controls.

Conclusion

This retrospective analysis documents the feasibility of detecting regional deformation abnormalities by echocardiography in patients with acute myocarditis confirmed by cMRI. The detection of pathological findings due to myocarditis requires the determination of regional deformation parameters, particularly rCS and LV rotation. The assessment of global strain values does not appear to be of critical value.

Impact of left ventricular hemodynamic forces in adult patients with treated aortic coarctation and preserved left ventricular systolic function

BACKGROUND

The LV myocardial strain and hemodynamic forces (HDFs) are innovative markers of LV function. Aortic coarctation is safely repaired in infancy; however, mortality and morbidity remain increased in later life. The study investigated the role of left ventricular myocardial deformation and HDFs in asymptomatic patients who underwent successful aortic coarctation repair.

METHODS

Clinical and echocardiographic data were analyzed from 42 repaired CoA, 32 ± 20 years after surgery, 2D echocardiographic global longitudinal strain (GLS), circumferential strain (GCS) and HDFs were determined. CoA patients were compared with 42 patients affected by blood hypertension and 84 healthy controls; all matched for age and gender.

RESULTS

All groups had normal LV ejection fraction (LVEF), dimensions, and volumes. CoA patients showed a significantly higher rate of LV mass indexed (p < .001) and left atrial volumes indexed (p < .001). LV myocardial and endocardial global longitudinal and circumferential strain were decreased in CoA patients (p < .001, p < .001; p = .032 and p < .001, respectively). HDF parameters such as LV longitudinal force, LV systolic longitudinal force and LV impulse (LVim) were uniformly reduced (p = .006, p = .001, and p = .001, respectively). LV myocardial strain and HDF parameter values were independently associated with hospitalization for heart failure on univariable Cox regression analysis.

CONCLUSION

Despite preserved LVEF, patients with CoA had lower LV myocardial strain and HDF parameters values, independently associated with hospitalization for heart failure.

Monitoring of Myocardial Involvement in Early Arrhythmogenic Right Ventricular Cardiomyopathy Across the Age Spectrum

BACKGROUND

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is characterized by fibrofatty replacement of primarily the right ventricular myocardium, a substrate for life-threatening ventricular arrhythmias (VAs). Repeated cardiac imaging of at-risk relatives is important for early disease detection. However, it is not known whether screening should be age-tailored.

OBJECTIVES

The goal of this study was to assess the need for age-tailoring of follow-up protocols in early ARVC by evaluating myocardial disease progression in different age groups.

METHODS

We divided patients with early-stage ARVC and genotype-positive relatives without overt structural disease and VA at first evaluation into 3 groups: age <30 years, 30 to 50 years, and ≥50 years. Longitudinal biventricular deformation characteristics were used to monitor disease progression. To link deformation abnormalities to underlying myocardial disease substrates, Digital Twins were created using an imaging-based computational modeling framework.

RESULTS

We included 313 echocardiographic assessments from 82 subjects (57% female, age 39 ± 17 years, 10% probands) during 6.7 ± 3.3 years of follow-up. Left ventricular global longitudinal strain slightly deteriorated similarly in all age groups (0.1%-point per year [95% CI: 0.05-0.15]). Disease progression in all age groups was more pronounced in the right ventricular lateral wall, expressed by worsening in longitudinal strain (0.6%-point per year [95% CI: 0.46-0.70]) and local differences in myocardial contractility, compliance, and activation delay in the Digital Twin. Six patients experienced VA during follow-up.

CONCLUSIONS

Disease progression was similar in all age groups, and sustained VA also occurred in patients aged >50 years without overt ARVC phenotype at first evaluation. Unlike recommended by current guidelines, our study suggests that follow-up of ARVC patients and relatives should not stop at older age.

Right ventricular peak systolic free wall longitudinal strain as a practical tool to detect right ventricular dysfunction in acute myocarditis

INTRODUCTION

Acute myocarditis is one of the etiologies of acute heart failure, chronic dilated cardiomyopathy, and cardiac mortality. The extent of right ventricular (RV) involvement and its impact on the course of the disease have been scarcely studied. This study aimed to evaluate both the prevalence of RV dysfunction in acute myocarditis and echocardiographic measures as a diagnostic tool for RV dysfunction compared with cardiac magnetic resonance imaging (CMR) findings.

METHODS

This retrospective study enrolled patients with a definite or probable acute myocarditis diagnosis based on the Lake Louise criteria in CMR and evaluated the diagnostic accuracy of echocardiographic measures in predicting RV dysfunction in CMR.

RESULTS

The study population consisted of 71 patients, including 54 men (76%), at a median (Q1-Q3) age of 33 (26-46) years. CMR detected RV dysfunction in 53.5% of the patients. The RV free wall peak systolic longitudinal strain showed the highest correlation (r = -.786, p < .001) and area under the curve (.919) with the RV ejection fraction in CMR, followed by the RV global peak systolic longitudinal strain and the RV fractional area change. The RV-free wall peak systolic longitudinal strain had a sensitivity of 92% and a specificity of 73% for the diagnosis of RV dysfunction in myocarditis. A cutoff value of -17.9% was 100% specific for RV systolic dysfunction.

CONCLUSIONS

Echocardiography, as a readily available tool, was predictive of and had acceptable accuracy for RV dysfunction in acute myocarditis compared with CMR.

The Agreement of a Two- and a Three-Dimensional Speckle-Tracking Global Longitudinal Strain

Background: Two-dimensional (2D) and three-dimensional (3D) speckle-tracking echocardiography (STE) enables assessment of myocardial function. Here, we examined the agreement between 2D and 3D STE measurement of a global longitudinal strain (GLS) in patients with normal left ventricle, reduced ejection fraction, and cardiac pacing. Methods: Our analysis included 90 consecutive patients (59% males; average age: 73.2 ± 11.2 years) examined between May 2019−December 2020, with valid 2D and 3D loops for further speckle-tracking strain analysis. Linear regression, Pearson correlation, and a Bland−Altman plot were used to quantify the association between 2D and 3D GLS and related segments, using the 17-segment American Heart Association (AHA) model. Analyses were performed in the entire study group and subgroups. Intra- and inter-observer variability of 2D and 3D GLS measurement was also performed in all participants. Results: We observed a strong correlation between 2D and 3D GLS measurements (R = 0.76, p < 0.001), which was higher in males (R = 0.78, p < 0.001) than females (R = 0.69, p < 0.001). Associated segment correlation was poor (R = 0.2−0.5, p < 0.01). The correlation between 2D and 3D GLS was weaker in individuals with ventricular pacing of >50% (R = 0.62, p < 0.001) than <50% (R = 0.8, p < 0.001), and in patients with LVEF of <35% (R = 0.69, p = 0.002) than >35% (R = 0.72, p < 0.001). Intra-observer variability for 2D and 3D GLS was 2 and 2.3%, respectively. Inter-observer variability for 2D and 3D GLS was 3.8 and 3.6%, respectively Conclusion: Overall 2D and 3D GLS were closely associated but not when analyzed per segment. It seems that GLS comparison is more representative of global shortening than local displacement. Right ventricular pacing and reduced left ventricular ejection fraction were associated with a reduced correlation between 2D and 3D GLS.

Echocardiographic Deformation Imaging for Early Detection of Genetic Cardiomyopathies: JACC Review Topic of the Week

Clinical screening of the relatives of patients with genetic cardiomyopathies is challenging, as they often lack detectable cardiac abnormalities at presentation. Life-threatening adverse events can already occur in these early stages of disease, so sensitive tools to reveal the earliest signs of disease are needed. The utility of echocardiographic deformation imaging for early detection has been explored for this population in multiple studies but has not been broadly implemented in clinical practice. The authors discuss contemporary evidence on the utility of deformation imaging in relatives of patients with genetic cardiomyopathies. The available body of data shows that deformation imaging reveals early disease-specific abnormalities in dilated cardiomyopathy, hypertrophic cardiomyopathy, and arrhythmogenic cardiomyopathy. Deformation imaging seems promising to enhance the screening and follow-up protocols in relatives, and the authors propose measures to accelerate its implementation in clinical care.

Introduction to Hemodynamic Forces Analysis: Moving Into the New Frontier of Cardiac Deformation Analysis

The potential relevance of blood flow for describing cardiac function has been known for the past 2 decades, but the association of clinical parameters with the complexity of fluid motion is still not well understood. Hemodynamic force (HDF) analysis represents a promising approach for the study of blood flow within the ventricular chambers through the exploration of intraventricular pressure gradients. Previous experimental studies reported the significance of invasively measured cardiac pressure gradients in patients with heart failure. Subsequently, advances in cardiovascular imaging allowed noninvasive assessment of pressure gradients during progression and resolution of ventricular dysfunction and in the setting of resynchronization therapy. The HDF analysis can amplify mechanical abnormalities, detect them earlier compared with conventional ejection fraction and strain analysis, and possibly predict the development of cardiac remodeling. Alterations in HDFs provide the earliest signs of impaired cardiac physiology and can therefore transform the existing paradigm of cardiac function analysis once implemented in routine clinical care. Until recently, the HDF investigation was possible only with contrast‐enhanced echocardiography and magnetic resonance imaging, precluding its widespread clinical use. A mathematical model, based on the first principle of fluid dynamics and validated using 4‐dimensional‐flow‐magnetic resonance imaging, has allowed HDF analysis through routine transthoracic echocardiography, making it more readily accessible for routine clinical use. This article describes the concept of HDF analysis and reviews the existing evidence supporting its application in several clinical settings. Future studies should address the prognostic importance of HDF assessment in asymptomatic patients and its incorporation into clinical decision pathways.

Initial Derivation of a Predictive Model for Left Ventricular Longitudinal Strain (LS) in Early Sepsis

Septic shock is a common deadly disease often associated with cardiovascular dysfunction. Left ventricular longitudinal strain (LV LS) has been proposed as a sensitive marker to measure cardiovascular function; however, it is not available universally in standard clinical echocardiograms. We sought to derive a predictive model for LV LS, using machine learning techniques with the hope that we may uncover surrogates for LV LS. We found that left ventricular ejection fraction, tricuspid annular plane systolic excursion, sepsis source, height, mitral valve Tei index, LV systolic dimension, aortic valve ejection time, and peak acceleration rate were all predictive of LV LS in this initial exploratory model. Future modeling work may uncover combinations of these variables which may be powerful surrogates for LV LS and cardiovascular function.

Uncertainty Quantification of Regional Cardiac Tissue Properties in Arrhythmogenic Cardiomyopathy Using Adaptive Multiple Importance Sampling

Introduction: Computational models of the cardiovascular system are widely used to simulate cardiac (dys)function. Personalization of such models for patient-specific simulation of cardiac function remains challenging. Measurement uncertainty affects accuracy of parameter estimations. In this study, we present a methodology for patient-specific estimation and uncertainty quantification of parameters in the closed-loop CircAdapt model of the human heart and circulation using echocardiographic deformation imaging. Based on patient-specific estimated parameters we aim to reveal the mechanical substrate underlying deformation abnormalities in patients with arrhythmogenic cardiomyopathy (AC). Methods: We used adaptive multiple importance sampling to estimate the posterior distribution of regional myocardial tissue properties. This methodology is implemented in the CircAdapt cardiovascular modeling platform and applied to estimate active and passive tissue properties underlying regional deformation patterns, left ventricular volumes, and right ventricular diameter. First, we tested the accuracy of this method and its inter- and intraobserver variability using nine datasets obtained in AC patients. Second, we tested the trueness of the estimation using nine in silico generated virtual patient datasets representative for various stages of AC. Finally, we applied this method to two longitudinal series of echocardiograms of two pathogenic mutation carriers without established myocardial disease at baseline. Results: Tissue characteristics of virtual patients were accurately estimated with a highest density interval containing the true parameter value of 9% (95% CI [0-79]). Variances of estimated posterior distributions in patient data and virtual data were comparable, supporting the reliability of the patient estimations. Estimations were highly reproducible with an overlap in posterior distributions of 89.9% (95% CI [60.1-95.9]). Clinically measured deformation, ejection fraction, and end-diastolic volume were accurately simulated. In presence of worsening of deformation over time, estimated tissue properties also revealed functional deterioration. Conclusion: This method facilitates patient-specific simulation-based estimation of regional ventricular tissue properties from non-invasive imaging data, taking into account both measurement and model uncertainties. Two proof-of-principle case studies suggested that this cardiac digital twin technology enables quantitative monitoring of AC disease progression in early stages of disease.

Optimal echocardiographic assessment of myocardial dysfunction for arrhythmic risk stratification in phospholamban mutation carriers

Aims 

Phospholamban (PLN) p.Arg14del mutation carriers are at risk of developing malignant ventricular arrhythmias (VAs) and/or heart failure. Currently, left ventricular ejection fraction (LVEF) plays an important role in risk assessment for VA in these individuals. We aimed to study the incremental prognostic value of left ventricular mechanical dispersion (LVMD) by echocardiographic deformation imaging for prediction of sustained VA in PLN p.Arg14del mutation carriers.

Methods and results

We included 243 PLN p.Arg14del mutation carriers, which were classified into three groups according to the ‘45/45’ rule: (i) normal left ventricular (LV) function, defined as preserved LVEF ≥45% with normal LVMD ≤45 ms (n = 139), (ii) mechanical LV dysfunction, defined as preserved LVEF ≥45% with abnormal LVMD >45 ms (n = 63), and (iii) overt LV dysfunction, defined as reduced LVEF <45% (n = 41). During a median follow-up of 3.3 (interquartile range 1.8–6.0) years, sustained VA occurred in 35 individuals. The negative predictive value of having normal LV function at baseline was 99% [95% confidence interval (CI): 92–100%] for developing sustained VA. The positive predictive value of mechanical LV dysfunction was 20% (95% CI: 15–27%). Mechanical LV dysfunction was an independent predictor of sustained VA in multivariable analysis [hazard ratio adjusted for VA history: 20.48 (95% CI: 2.57–162.84)].

Conclusion 

LVMD has incremental prognostic value on top of LVEF in PLN p.Arg14del mutation carriers, particularly in those with preserved LVEF. The ‘45/45’ rule is a practical approach to echocardiographic risk stratification in this challenging group of patients. This approach may also have added value in other diseases where LVEF deterioration is a relative late marker of myocardial dysfunction.

A head-to-head comparison of speckle tracking echocardiography and feature tracking cardiovascular magnetic resonance imaging in right ventricular deformation

AIMS

Speckle tracking echocardiography (STE) and feature tracking cardiovascular magnetic resonance imaging (FT-CMR) are advanced imaging techniques which are both used for quantification of global and regional myocardial strain. Direct comparisons of STE and FT-CMR regarding right ventricular (RV) strain analysis are limited. We aimed to study clinical performance, correlation and agreement of RV strain by these techniques, using arrhythmogenic right ventricular cardiomyopathy (ARVC) as a model for RV disease.

METHODS AND RESULTS

We enrolled 110 subjects, including 34 patients with definite ARVC, 30 preclinical relatives of ARVC patients, and 46 healthy control subjects. Global and regional RV longitudinal peak strain (PS) were measured by STE and FT-CMR. Both modalities showed reduced strain values in ARVC patients compared to ARVC relatives (STE global PS: P < 0.001; FT-CMR global PS: P < 0.001) and reduced strain values in ARVC relatives compared to healthy control subjects (STE global PS: P = 0.042; FT-CMR global PS: P = 0.084). There was a moderate, albeit significant correlation between RV strain values obtained by STE and FT-CMR [global PS r = 0.578 (95% confidence interval 0.427-0.697), P < 0.001]. Agreement between the techniques was weak (limits of agreement for global PS: ±11.8%). Correlation and agreement both deteriorated when regional strain was studied.

CONCLUSION

RV STE and FT-CMR show a similar trend within the spectrum of ARVC and have significant correlation, but inter-modality agreement is weak. STE and FT-CMR may therefore both individually have added value for assessment of RV function, but RV PS values obtained by these techniques currently cannot be used interchangeably in clinical practice.

Right ventricular strain rate during exercise accurately identifies male athletes with right ventricular arrhythmias

AIMS

Athletes with right ventricular (RV) arrhythmias, even in the absence of desmosomal mutations, may have subtle RV abnormalities which can be unmasked by deformation imaging. As exercise places a disproportionate stress on the right ventricle, evaluation of cardiac function and deformation during exercise might improve diagnostic performance.

METHODS AND RESULTS

We performed bicycle stress echocardiography in 17 apparently healthy endurance athletes (EAs), 12 non-athletic controls (NAs), and 17 athletes with RV arrhythmias without desmosomal mutations (EI-ARVCs) and compared biventricular function at rest and during low (25% of upright peak power) and moderate intensity (60%). At rest, we observed no differences in left ventricular (LV) or RV function between groups. During exercise, however, the increase in RV fractional area change (RVFAC), RV free wall strain (RVFWSL), and strain rate (RVFWSRL) were significantly attenuated in EI-ARVCs as compared to EAs and NAs. At moderate exercise intensity, EI-ARVCs had a lower RVFAC, RVFWSL, and RVFWSRL (all P < 0.01) compared to the control groups. Exercise-related increases in LV ejection fraction, strain, and strain rate were also attenuated in EI-ARVCs (P < 0.05 for interaction). Exercise but not resting parameters identified EI-ARVCs and RVFWSRL with a cut-off value of >-2.35 at moderate exercise intensity had the greatest accuracy to detect EI-ARVCs (area under the curve 0.95).

CONCLUSION

Exercise deformation imaging holds promise as a non-invasive diagnostic tool to identify intrinsic RV dysfunction concealed at rest. Strain rate appears to be the most accurate parameter and should be incorporated in future, prospective studies to identify subclinical disease in an early stage.

Right Ventricular Functional Abnormalities in Arrhythmogenic Cardiomyopathy: Association With Life-Threatening Ventricular Arrhythmias

OBJECTIVES

This study aimed to perform an external validation of the value of right ventricular (RV) deformation patterns and RV mechanical dispersion in patients with arrhythmogenic cardiomyopathy (AC). Secondly, this study assessed the association of these parameters with life-threatening ventricular arrhythmia (VA).

BACKGROUND

Subtle RV dysfunction assessed by echocardiographic deformation imaging is valuable in AC diagnosis and risk prediction. Two different methods have emerged, the RV deformation pattern recognition and RV mechanical dispersion, but these have neither been externally validated nor compared.

METHODS

We analyzed AC probands and mutation-positive family members, matched from 2 large European referral centers. We performed speckle tracking echocardiography, whereby we classified the subtricuspid deformation patterns from normal to abnormal and assessed RV mechanical dispersion from 6 segments. We defined VA as sustained ventricular tachycardia, appropriate implantable cardioverter-defibrillator therapy, or aborted cardiac arrest.

RESULTS

We included 160 subjects, 80 from each center (43% proband, 55% women, age 41 ± 17 years). VA had occurred in 47 (29%) subjects. In both cohorts, patients with a history of VA showed abnormal deformation patterns (96% and 100%) and had greater RV mechanical dispersion (53 ± 30 ms vs. 30 ± 21 ms; p < 0.001 for the total cohort). Both parameters were independently associated to VA (adjusted odds ratio: 2.71 [95% confidence interval: 1.47 to 5.00] per class step-up, and 1.26 [95% confidence interval: 1.07 to 1.49]/10 ms, respectively). The association with VA significantly improved when adding RV mechanical dispersion to pattern recognition (net reclassification improvement 0.42; p = 0.02 and integrated diagnostic improvement 0.06; p = 0.01).

CONCLUSIONS

We externally validated 2 RV dysfunction parameters in AC. Adding RV mechanical dispersion to RV deformation patterns significantly improved the association with life-threatening VA, indicating incremental value.

Early Mechanical Alterations in Phospholamban Mutation Carriers: Identifying Subclinical Disease Before Onset of Symptoms

OBJECTIVES

This study aimed to explore echocardiographic characteristics of phospholamban (PLN) p.Arg14del mutation carriers to investigate whether structural and/or functional abnormalities could be identified before onset of symptoms.

BACKGROUND

Carriers of the genetic PLN p.Arg14del mutation may develop arrhythmogenic and/or dilated cardiomyopathy. Overt disease is preceded by a pre-symptomatic phase of variable length in which disease expression seems to be absent.

METHODS

PLN p.Arg14del mutation carriers with an available echocardiogram were included. Mutation carriers were classified as pre-symptomatic if they had no history of ventricular arrhythmias (VAs), a premature ventricular complex count of <500/24 h, and a left ventricular (LV) ejection fraction of ≥45%. In addition, we included 70 control subjects with similar age and sex distribution as the pre-symptomatic mutation carriers. Comprehensive echocardiographic analysis (including deformation imaging) was performed.

RESULTS

The final study population consisted of 281 PLN p.Arg14del mutation carriers, 139 of whom were classified as pre-symptomatic. In comparison to control subjects, pre-symptomatic mutation carriers had lower global longitudinal strain and higher LV mechanical dispersion (both p < 0.001). In addition, post-systolic shortening (PSS) in the LV apex was observed in 43 pre-symptomatic mutation carriers (31%) and in none of the control subjects. During a median follow-up of 3.2 years (interquartile range: 2.1 to 5.6 years) in 104 pre-symptomatic mutation carriers, nonsustained VA occurred in 13 (13%). Presence of apical PSS was the strongest echocardiographic predictor of VA (multivariable hazards ratio: 5.11; 95% confidence interval [CI]: 1.37 to 19.08; p = 0.015), which resulted in a negative predictive value of 96% (95% CI: 89% to 98%) and a positive predictive value of 29% (95% CI: 21% to 40%).

CONCLUSIONS

Global and regional LV mechanical alterations in PLN p.Arg14del mutation carriers precede arrhythmic symptoms and overt structural disease. Pre-symptomatic mutation carriers with normal deformation patterns in the apex are at low risk of developing VA within 3 years, whereas mutation carriers with apical PSS appear to be at higher risk.

Three-dimensional echocardiography to identify right ventricular dilatation in patients with corrected Fallot anomaly or pulmonary stenosis

Background

3‐Dimensional Echocardiography allows measuring volumes and parameters of myocardial deformation (strain). Myocardial strain has been suggested to be superior to conventional echo parameters in the assessment of right ventricular (RV) function. Myocardial strain can be assessed by cardiac magnetic resonance (CMR) or two‐ and three‐dimensional echocardiography (2D and 3DEcho). We performed a comprehensive assessment of the RV based on 3DEcho and compared the results with those based on CMR and 2DEcho.

Methods

36 patients with corrected heart defects underwent CMR and 3DEcho to assess RV volume, strain and cardio pulmonary exercise testing with peak VO₂ measurement. 2DEcho was used for reference.

Results

There was a moderate correlation between 3DEcho and CMR for measuring RV end‐diastolic and end‐systolic volumes (r = .82 and .72). 3DEcho tended to underestimate the RV volumes, mean difference EDV 8.5 ± 33 ml (CI −2.8; 19.7 ml) and ESV 13.2 ± 29 ml (CI 3.3; 23 ml). According to method‐specific reference values for RVEDV, 34/35 (3DEcho) and 29/36 (CMR) were dilated. Among those dilated according to CMR, all were identified by 3DEcho. The coefficient of correlation between RV atrioventricular plane displacement measured by CMR and tricuspid annular plane systolic excursion measured by 3D and 2DEcho was r = .6 for both. 2DEcho measured lower LV volumes than CMR. LVEF and GLS were similar in 2DEcho, 3DEcho and CMR. Patients with CMR‐determined RV free wall strain ≤ −14% tended to have lower peak VO₂.

Conclusions

Although 3DEcho underestimated RV volumes, it successfully identified all patients with RV dilatation based on method‐specific reference values.

Head-to-head comparison of cardiovascular MR feature tracking cine versus acquisition-based deformation strain imaging using myocardial tagging and strain encoding

PURPOSE

Myocardial feature-tracking (FT) deformation imaging is superior for risk stratification compared with volumetric approaches. Because there is no clear recommendation regarding FT postprocessing, we compared different FT-strain analyses with reference standard techniques, including tagging and strain-encoded (SENC) MRI.

METHODS

Feature-tracking software from four different vendors (TomTec, Medis, Circle [CVI], and Neosoft), tagging (Segment), and fastSENC (MyoStrain) were used to determine left ventricular global circumferential strains (GCS) and longitudinal strains (GLS) in 12 healthy volunteers and 12 patients with heart failure. Variability and agreements were assessed using intraclass correlation coefficients for absolute agreement (ICCa) and consistency (ICCc) as well as Pearson correlation coefficients.

RESULTS

For FT-GCS, consistency was excellent comparing different FT vendors (ICCc = 0.84-0.97, r = 0.86-0.95) and in comparison to fast SENC (ICCc = 0.78-0.89, r = 0.73-0.81). FT-GCS consistency was excellent compared with tagging (ICCc = 0.79-0.85, r = 0.74-0.77) except for TomTec (ICCc = 0.68, r = 0.72). Absolute FT-GCS agreements among FT vendors were highest for CVI and Medis (ICCa = 0.96) and lowest for TomTec and Neosoft (ICCa = 0.32). Similarly, absolute FT-GCS agreements were excellent for CVI and Medis compared with both tagging and fast SENC (ICCa = 0.84-0.88), good to excellent for Neosoft (ICCa = 0.77 and 0.64), and lowest for TomTec (ICCa = 0.41 and 0.47). For FT-GLS, consistency was excellent (ICCc ≥ 0.86, r ≥ 0.76). Absolute agreements among FT vendors were excellent (ICCa = 0.91-0.93) or good to excellent for TomTec (ICCa = 0.69-0.85). Absolute agreements (ICCa) were good (CVI 0.70, Medis 0.60) and fair (TomTec 0.41, Neosoft 0.59) compared with tagging, but excellent compared with fast SENC (ICCa = 0.77-0.90).

CONCLUSION

Although absolute agreements differ depending on deformation assessment approaches, consistency and correlation are consistently high regardless of the method chosen, thus indicating reliable strain assessment. Further standardisation and introduction of uniform references is warranted for routine clinical implementation.

Echocardiographic reference ranges for normal left ventricular layer-specific strain: results from the EACVI NORRE study

AIMS

To obtain the normal range for 2D echocardiographic (2DE) measurements of left ventricular (LV) layer-specific strain from a large group of healthy volunteers of both genders over a wide range of ages.

METHODS AND RESULTS

A total of 287 (109 men, mean age: 46 ± 14 years) healthy subjects were enrolled at 22 collaborating institutions of the EACVI Normal Reference Ranges for Echocardiography (NORRE) study. Layer-specific strain was analysed from the apical two-, three-, and four-chamber views using 2DE software. The lowest values of layer-specific strain calculated as ±1.96 standard deviations from the mean were -15.0% in men and -15.6% in women for epicardial strain, -16.8% and -17.7% for mid-myocardial strain, and -18.7% and -19.9% for endocardial strain, respectively. Basal-epicardial and mid-myocardial strain decreased with age in women (epicardial; P = 0.008, mid-myocardial; P = 0.003) and correlated with age (epicardial; r = -0.20, P = 0.007, mid-myocardial; r = -0.21, P = 0.006, endocardial; r = -0.23, P = 0.002), whereas apical-epicardial, mid-myocardial strain increased with the age in women (epicardial; P = 0.006, mid-myocardial; P = 0.03) and correlated with age (epicardial; r = 0.16, P = 0.04). End/Epi ratio at the apex was higher than at the middle and basal levels of LV in men (apex; 1.6 ± 0.2, middle; 1.2 ± 0.1, base 1.1 ± 0.1) and women (apex; 1.6 ± 0.1, middle; 1.1 ± 0.1, base 1.2 ± 0.1).

CONCLUSION

The NORRE study provides useful 2DE reference ranges for novel indices of layer-specific strain.

Early Detection of Myocardial Damage: A Multimodality Approach

Cardiovascular diseases are possible complications of antineoplastic treatment and may lead to premature morbidity and mortality among cancer survivors. A symptom-based follow-up is ineffective, and there are growing evidences that early detection of myocardial damage in patients treated with antineoplastic drugs is the key point to prevent the occurrence of damage and improve the prognosis of these patients. Different techniques have been proposed to monitor cardiac function in oncologic patients such as cardiac imaging (echocardiography, nuclear imaging, and cardiac magnetic resonance) and biomarkers (troponin and natriuretic peptides). The European Association of Cardiovascular Imaging/American Society of Echocardiography consensus document encourages an integrated approach to early detect cardiotoxicity.

Arrhythmogenic Right Ventricular Cardiomyopathy in a Pediatric Patient

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is rarely diagnosed in childhood. We describe the case of a 9-year-old girl with genetically confirmed ARVC who presented with syncope, ventricular arrhythmia, and biventricular myocardial dysfunction. This case highlights the need for development of pediatric ARVC diagnosis criteria specific for pediatric patients and discusses potential diagnostic improvement using echocardiographic deformation imaging. (Level of Difficulty: Beginner.)

High-frequency ultrasound deformation imaging for adult zebrafish during heart regeneration

Background

The adult human heart cannot efficiently generate new cardiac muscle cells in response to injury, and, therefore, cardiac injury results in irreversible damage to cardiac functions. The zebrafish (Danio rerio) is a crucial animal model in cardiac research because of its remarkable capacity for tissue regeneration. An adult zebrafish can completely regenerate cardiac tissue without a scar being formed, even after 20% of its ventricular myocardium has been resected. Zebrafish have been utilized in developmental biology and genetics research; however, the details of myocardium motions during their cardiac cycle in different regeneration phases are still not fully understood.

Methods

In this study, we used a 70-MHz high-resolution ultrasound deformation imaging system to observe the functional recovery of zebrafish hearts after amputation of the ventricular apex.

Results

The myocardial deformation and cardiac output (CO) were measured in different regeneration phases relative to the day of amputation. In response to the damage to the heart, the peak systolic strain (ε_max) and strain during ejection time (ε_ej) were lower than normal at 3 days after the myocardium amputation. The CO had normalized to the baseline values at 7 days after surgery.

Conclusions

Our results confirm that the imaging system constructed for this study is suitable for examining zebrafish cardiac functions during heart regeneration.

Independent parameters of left atrium function in hypertensive heart disease

BACKGROUND

The left atrium reservoir function has an important role in the global cardiac performance and is determined by multiple cardiac and extra-cardiac factors. A new parameter is introduced, the independent strain, which quantifies left atrium reservoir phase deformation during isovolumetric relaxation.

AIMS

Is evaluated whether independent strain can identify intrinsic atrial myocardial damage in hypertension.

MATERIAL AND METHODS

Prospective observational study in which echocardiography was done to 50 hypertensive patients and 80 healthy volunteers. Myocardial deformation was evaluated with two-dimensional speckle tracking and left atrium volumes were calculated whit 3D-echocardiography.

RESULTS

In hypertensive patients, the indexed left atrium volume was greater than in the control group (34 ± 7.8 vs 24 ± 4.9 mL/m² ); strain of pump (-5.7 ± 2.4% vs -17±3.5%) and reservoir phases (34 ± 9% vs 48 ± 10%) were worst. The minimum left atrium volume was higher (26 ± 10 vs 15 ± 8 mL) and left atrium independent strain was lower in hypertensive patients (4.0% vs 6.5%, P = .001). Left atrium independent strain only correlated with minimum left atrium volume (r = -.31, P = .048).

DISCUSSION

The left ventricle longitudinal performance has an important contributing role in the left atrium reservoir function; despite this finding, the independent strain was unrelated to left ventricle longitudinal function.

CONCLUSION

Independent strain can identify atrial myocyte contractile dysfunction in hypertension given the relative absence of hemodynamic loads during this period. Additionally, quantification of left atrium minimum volume suggests indirectly the presence of atrial myocyte contractile dysfunction.

Deformation imaging to assess global and regional effects of cardiac regenerative therapy in ischaemic heart disease: A systematic review

Currently, left ventricular ejection fraction (LVEF) is the most common endpoint in cardiovascular stem cell therapy research. However, this global measure of cardiac function might not be suitable to detect the regional effects sorted by this therapy and is hampered by high operator variability and loading dependency. Deformation imaging might be more accurate in detecting potential regional functional improvements by cardiac regenerative therapy. The aim of this systematic review is to provide a comprehensive overview of current literature on the value of deformation imaging in cardiac regenerative therapy. A systematic review of current literature available on PubMed, Embase, and Cochrane databases was performed regarding both animal and patient studies in which deformation imaging was used to study cardiac cell therapy. After critical appraisal, outcomes regarding study design, type of cell therapy, procedural characteristics, outcome measure, method for measuring strain, and efficacy on both LVEF and deformation parameters were depicted. A total of 30 studies, 15 preclinical and 15 clinical, were included for analysis. Deformation outcomes improved significantly in 14 out of 15 preclinical studies and in 10 out of 15 clinical studies, whereas LVEF improved in 12 and 4 articles, respectively. Study designs and used deformation outcomes varied significantly among the included papers. Six studies found a positive effect on deformation outcomes without LVEF improvement. Hence, deformation imaging seems at least equal, and perhaps superior, to LVEF measurement in the assessment of cardiac regenerative therapy. However, strategies varied substantially and call for a standardized approach.

Left Ventricular Response to Cardiac Resynchronization Therapy: Insights From Hemodynamic Forces Computed by Speckle Tracking

Aims: Despite continuous efforts in improving the selection process, the rate of non-responders to cardiac resynchronization therapy (CRT) remains high. Recent studies on intraventricular blood flow suggested that the alignment of hemodynamic forces (HDFs) may be a reproducible biomarker of mechanical dyssynchrony. We aimed to explore the relationship between pacing-induced realignment of HDFs and positive response to CRT. Methods and results: We retrospectively analyzed 38 patients from the CRT database of our institution fulfilling the inclusion criteria for HDFs-related echocardiographic assessment early pre and post CRT implantation, with available mid-term follow-up (≥ 6 months) evaluation. Standard echocardiographic and deformation parameters early pre and post CRT implantation were integrated with the measurement of HFDs through novel methods based on speckle-tracking analysis. At midterm follow-up 71% of patients were classified as responders (reduction of Left Ventricular Systolic Volume Indexed ≥ 15%). Patients did not display significant changes between close evaluations pre and post-implant in terms of ejection fraction and strain metrics. A significant reduction of the ratio between the amplitudes of transversal and longitudinal force components was found. The variation of this ratio strongly correlates (R² =0.60) with Left Ventricular (LV) end-systolic volume variation at mid-term follow up. Conclusion: Pacing-induced realignment of HDFs is associated with CRT efficacy at follow up. These preliminary results claim for dedicated prospective clinical studies testing the potential impact of HDFs study for patient selection and pacing optimization in CRT.

The Prognostic Value of Right Ventricular Deformation Imaging in Early Arrhythmogenic Right Ventricular Cardiomyopathy

OBJECTIVES

The aim of this study was to investigate the prognostic value of echocardiographic deformation imaging in arrhythmogenic right ventricular cardiomyopathy (ARVC) to optimize family screening protocols.

BACKGROUND

ARVC is characterized by variable disease expressivity among family members, which complicates family screening protocols. Previous reports have shown that echocardiographic deformation imaging detects abnormal right ventricular (RV) deformation in the absence of established disease expression in ARVC.

METHODS

First-degree relatives of patients with ARVC were evaluated according to 2010 task force criteria, including RV deformation imaging (n = 128). Relatives fulfilling structural task force criteria were excluded for further analysis. At baseline, deformation patterns of the subtricuspid region were scored as type I (normal deformation), type II (delayed onset, decreased systolic peak, and post-systolic shortening), or type III (systolic stretching and large post-systolic shortening). The final study population comprised relatives who underwent a second evaluation during follow-up. Disease progression was defined as the development of a new 2010 task force criterion during follow-up that was absent at baseline.

RESULTS

Sixty-five relatives underwent a second evaluation after a mean follow-up period of 3.7 ± 2.1 years. At baseline, 28 relatives (43%) had normal deformation (type I), and 37 relatives (57%) had abnormal deformation (type II or III) in the subtricuspid region. Disease progression occurred in 4% of the relatives with normal deformation at baseline and in 43% of the relatives with abnormal deformation at baseline (p < 0.001). Positive and negative predictive values of abnormal deformation were, respectively, 43% (95% confidence interval: 27% to 61%) and 96% (95% confidence interval: 82% to 100%).

CONCLUSIONS

Normal RV deformation in the subtricuspid region is associated with absence of disease progression during nearly 4-year follow-up in relatives of patients with ARVC. Abnormal RV deformation seems to precede the established signs of ARVC. RV deformation imaging may potentially play an important role in ARVC family screening protocols.

Echocardiographic assessment in patients with chronic kidney disease: Current update

Patients with chronic kidney disease (CKD) carry a high cardiovascular risk. An abundance of evidence has emerged in recent years establishing minor reductions in estimated glomerular filtration rate as an independent risk factor for cardiovascular mortality. Additionally, cardiac changes, such as left ventricular hypertrophy and impaired left ventricular systolic function, have been associated with an unfavorable prognosis. Despite the significant prevalence of underlying cardiac abnormalities, symptoms may not manifest in many patients with CKD. A range of available and emerging echocardiographic modalities may assist with diagnosing heart disease in CKD. Furthermore, some of these emerging techniques can give an important insight into the pathophysiology of subclinical dysfunction in CKD. This review discusses how current and emerging echocardiographic modalities such as speckle tracking echocardiography and 3D echocardiography might help cardiologists in providing important information to help with diagnosis and risk stratification of cardiac-related morbidity and mortality in patients with renal disease, as well applicability of these tools to current clinical practice.

Cardiovascular Magnetic Resonance Myocardial Feature Tracking: Concepts and Clinical Applications

Heart failure-induced cardiovascular morbidity and mortality constitute a major health problem worldwide and result from diverse pathogeneses, including coronary artery disease, nonischemic cardiomyopathies, and arrhythmias. Assessment of cardiovascular performance is important for early diagnosis and accurate management of patients at risk of heart failure. During the past decade, cardiovascular magnetic resonance myocardial feature tracking has emerged as a useful tool for the quantitative evaluation of cardiovascular function. The method allows quantification of biatrial and biventricular mechanics from measures of deformation: strain, torsion, and dyssynchrony. The purpose of this article is to review the basic principles, clinical applications, accuracy, and reproducibility of cardiovascular magnetic resonance myocardial feature tracking, highlighting the prognostic implications. It will also provide an outlook on how this field might evolve in the future.

Simultaneous Assessment of Myocardial Perfusion, Wall Motion, and Deformation during Myocardial Contrast Echocardiography: A Feasibility Study

AIMS

Ultrasound contrast agents may be used for the assessment of regional wall motion and myocardial perfusion, but are generally considered not suitable for deformation analysis. The aim of our study was to assess the feasibility of deformation imaging on contrast-enhanced images using a novel methodology.

METHODS AND RESULTS

We prospectively enrolled 40 patients who underwent stress echocardiography with continuous intravenous infusion of SonoVue for the assessment of myocardial perfusion imaging with flash replenishment technique. We compared longitudinal strain (Lε) values, assessed with a vendor-independent software (2D CPA), on 68 resting contrast-enhanced and 68 resting noncontrast recordings. Strain analysis on contrast recordings was evaluated in the first cardiac cycles after the flash. Tracking of contrast images was deemed feasible in all subjects and in all views. Contrast administration improved image quality and increased the number of segments used for deformation analysis. Lε of noncontrast and contrast-enhanced images were statistically different (-18.8 ± 4.5% and -22.8 ± 5.4%, respectively; P < 0.001), but their correlation was good (ICC 0.65, 95%CI 0.42-0.78). Patients with resting wall-motion abnormalities showed lower Lε values on contrast recordings (-18.6 ± 6.0% vs. -24.2 ± 5.5%, respectively; P < 0.01). Intra-operator and inter-operator reproducibility was good for both noncontrast and contrast images with no statistical differences.

CONCLUSIONS

Our study shows that deformation analysis on postflash contrast-enhanced images is feasible and reproducible. Therefore, it would be possible to perform a simultaneous evaluation of wall-motion abnormalities, volumes, ejection fraction, perfusion defects, and cardiac deformation on the same contrast recording.

Exercise Strain Echocardiography in Patients With a Hemodynamically Significant Myocardial Bridge Assessed by Physiological Study

Background

Although a myocardial bridge (MB) is often regarded as a benign coronary variant, recent studies have associated MB with focal myocardial ischemia. The physiological consequences of MB on ventricular function during stress have not been well established.

Methods and Results

We enrolled 58 patients with MB of the left anterior descending artery, diagnosed by intravascular ultrasound. Patients underwent invasive physiological evaluation of the MB by diastolic fractional flow reserve during dobutamine challenge and exercise echocardiography. Septal and lateral longitudinal strain (LS) were assessed at rest and immediately after exercise and compared with strain of matched controls. Absolute and relative changes in strain were also calculated. The mean age was 42.5±16.0 years. Fifty‐five patients had a diastolic fractional flow reserve ≤0.76. At rest, there was no significant difference between the 2 groups in septal LS (19.0±1.8% for patients with MB versus 19.2±1.5% for control, P=0.53) and lateral LS (20.1±2.0% versus 20.0±1.6%, P=0.83). With stress, compared with controls, patients with MB had a lower peak septal LS (18.9±2.6% versus 21.7±1.6%, P<0.001) and lower absolute (−0.1±2.1% versus 2.5±1.3%, P<0.001) and relative change (−0.6±11.2% versus 13.1±7.8%, P<0.001) in septal LS, whereas there was no significant difference in lateral LS. In multivariate analysis, diastolic fractional flow reserve and length were independent determinants of lower changes in septal LS.

Conclusions

Patients with a hemodynamically significant MB, determined by invasive diastolic fractional flow reserve, have significantly lower change in septal LS on exercise echocardiography, suggesting that septal LS may be useful for noninvasively assessing the hemodynamic significance of an MB.

Comparison of cardiac displacement and strain imaging using ultrasound radiofrequency and envelope signals

Echocardiographic strain imaging is a promising new method for quantifying and displaying the health of cardiac muscle. Accurate regional myocardial function analysis requires high spatial and temporal resolution in addition to fidelity to the underlying deformation. However, all current clinical approaches use speckle-tracking algorithms applied to B-mode images derived from envelope signals. Such approaches are inherently of lower spatial resolution, since they require larger data blocks for deformation tracking due to the absence of phase information. In this paper, we compare the strain estimation performance using B-mode, envelope and radiofrequency signals, utilizing data acquired from a uniformly elastic tissue mimicking phantom, cardiac simulation, and clinical in vivo data. Signal-to-noise ratio improvements using radiofrequency signals for linear and phased array geometries were 5.80 dB and 9.48 dB over that obtained with envelope signals (at peak strain) in phantom studies, respectively. Cardiac simulation studies demonstrate that when averaged over the two cardiac cycles, the mean standard deviation of estimated strain using envelope signals from two of the six segments for a short-axes view (anterior and anterolateral) were 48% and 44% higher than that obtained using radiofrequency signals. These segments were chosen since one was along while the other was situated lateral to the beam propagation direction. In a similar manner, in vivo analysis on a volunteer also indicate that the standard deviation of the estimated strain using B-mode and envelope signals were 16% and 42% higher than that obtained using radiofrequency signals in the anteroseptal segment, and 45% and 27% in the anterior segment. These results demonstrate the significant reduction in the variability of strain estimated along with improvements in the spatial resolution and signal-to-noise ratios obtained using radiofrequency signals.