Utility of strain echocardiography at rest and after stress testing in arrhythmogenic right ventricular dysplasia

Stress echocardiography in heart failure patients: additive value and caveats

Heart failure (HF) is a clinical syndrome characterized by well-defined signs and symptoms due to structural and/or myocardial functional impairment, resulting in raised intracardiac pressures and/or inadequate cardiac stroke volume at rest or during exercise. This could derive from direct ischemic myocardial injury or other chronic pathological conditions, including valvular heart disease (VHD) and primary myocardial disease. Early identification of HF etiology is essential for accurate diagnosis and initiation of early and appropriate treatment. Thus, the presence of accurate means for early diagnosis of HF symptoms or subclinical phases is fundamental, among which echocardiography being the first line diagnostic investigation. Echocardiography could be performed at rest, to identify overt structural and functional abnormalities or during physical or pharmacological stress, in order to elicit subclinical myocardial function impairment e.g. wall motion abnormalities and raised ventricular filling pressures. Beyond diagnosis of ischemic heart disease, stress echocardiography (SE) has recently shown its unique value for the evaluation of diastolic heart failure, VHD, non-ischemic cardiomyopathies and pulmonary hypertension, with recommendations from international societies in several clinical settings. All these features make SE an important additional tool, not only for diagnostic assessment, but also for prognostic stratification and therapeutic management of patients with HF. In this review, the unique value of SE in the evaluation of HF patients will be described, with the objective to provide an overview of the validated methods for each setting, particularly for HF management.

Right Ventricular Function in Arrhythmogenic Right Ventricular Cardiomyopathy: Potential Value of Strain Echocardiography

Arrhythmogenic right ventricular cardiomyopathy is an inherited cardiomyopathy, characterized by abnormal cell adhesions, disrupted intercellular signaling, and fibrofatty replacement of the myocardium. These changes serve as a substrate for ventricular arrhythmias, placing patients at risk of sudden cardiac death, even in the early stages of the disease. Current echocardiographic criteria for diagnosing arrhythmogenic right ventricular cardiomyopathy lack sensitivity, but novel markers of cardiac deformation are not subject to the same technical limitations as current guideline-recommended measures. Measuring cardiac deformation using speckle tracking allows for meticulous quantification of global systolic function, regional function, and dyssynchronous contraction. Consequently, speckle tracking to quantify myocardial strain could potentially be useful in the diagnostic process for the determination of disease progression and to assist risk stratification for ventricular arrhythmias and sudden cardiac death. This narrative review provides an overview of the potential use of different myocardial right ventricular strain measures for characterizing right ventricular dysfunction in arrhythmogenic right ventricular cardiomyopathy and its utility in assessing the risk of ventricular arrhythmias.

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

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

The athlete's heart: insights from echocardiography

The manifestations of the athlete's heart can create diagnostic challenges during an echocardiographic assessment. The classifications of the morphological and functional changes induced by sport participation are often beyond 'normal limits' making it imperative to identify any overlap between pathology and normal physiology. The phenotype of the athlete's heart is not exclusive to one chamber or function. Therefore, in this narrative review, we consider the effects of sporting discipline and training volume on the holistic athlete's heart, as well as demographic factors including ethnicity, body size, sex, and age.

Hyperoxia-induced deterioration of diastolic function in anaesthetised patients with coronary artery disease - Randomised crossover trial

Background

There are no current recommendations for oxygen titration in patients with stable coronary artery disease. This study investigates the effect of iatrogenic hyperoxia on cardiac function in patients with coronary artery disease undergoing general anaesthesia.

Methods

Patients scheduled for elective coronary artery bypass graft surgery were prospectively recruited into this randomised crossover clinical trial. All patients were exposed to inspired oxygen fractions of 0.3 (normoxaemia) and 0.8 (hyperoxia) in randomised order. A transoesophageal echocardiographic imaging protocol was performed during each exposure. Primary analysis investigated changes in 3D peak strain, whereas secondary analyses investigated other systolic and diastolic responses.

Results

There was no statistical difference in systolic function between normoxaemia and hyperoxia. However, the response in systolic function to hyperoxia was dependent on ventricular function at normoxaemia. Patients with a normoxaemic left ventricular (LV) global longitudinal strain (GLS) poorer than the derived cut-off (>-15.4%) improved with hyperoxia (P<0.01), whereas in patients with normoxaemic LV-GLS <-15.4%, LV-GLS worsened with transition to hyperoxia (P<0.01). The same was seen for right ventricular GLS with a cut-off at -24.1%. Diastolic function worsened during hyperoxia indicated by a significant increase of averaged E/e' (8.6 [2.6]. vs 8.2 [2.4], P=0.01) and E/A ratio (1.4 (0.4) vs 1.3 (0.4), P=0.01).

Conclusions

Although the response of biventricular systolic variables is dependent on systolic function at normoxaemia, diastolic function consistently worsens under hyperoxia. In coronary artery disease, intraoperative strain analysis may offer guidance for oxygen titration.

Clinical trial registration

NCT04424433.

The use of 2-D speckle tracking echocardiography in differentiating healthy adolescent athletes with right ventricular outflow tract dilation from patients with arrhythmogenic cardiomyopathy

AIMS

Echocardiographic assessment of adolescent athletes for arrhythmogenic cardiomyopathy (ACM) can be challenging owing to right ventricular (RV) exercise-related remodelling, particularly RV outflow tract (RVOT) dilation. The aim of this study is to evaluate the role of RV 2-D speckle tracking echocardiography (STE) in comparing healthy adolescent athletes with and without RVOT dilation to patients with ACM.

METHODS AND RESULTS

A total of 391 adolescent athletes, mean age 14.5 ± 1.7 years, evaluated at three sports academies between 2014 and 2019 were included, and compared to previously reported ACM patients (n = 38 definite and n = 39 borderline). Peak systolic RV free wall (RVFW-S_l), global and segmental strain (S_l), and corresponding strain rates (SR_l) were calculated. The participants meeting the major modified Task Force Criteria (mTFC) for RVOT dilation were defined as mTFC+ (n = 58, 14.8%), and the rest as mTFC- (n = 333, 85.2%). Mean RVFW-S_l was -27.6 ± 3.4% overall, -28.2 ± 4.1% in the mTFC+ group and - 27.5 ± 3.3% in the mTFC- group. mTFC+ athletes had normal RV-FW-S_l when compared to definite (-29% vs -19%, p < 0.001) and borderline ACM (-29% vs -21%, p < 0.001) cohorts. In addition, all mean global and regional S_l and SR_l values were no worse in the mTFC+ group compared to the mTFC- (p values range < 0.0001 to 0.1, inferiority margin of 2% and 0.1 s^-1 respectively).

CONCLUSIONS

In athletes with RVOT dilation meeting the major mTFC, STE evaluation of the RV can demostrate normal function and differentiate physiological remodelling from pathological changes found in ACM, improving screening in grey-area cases.

The quest for determination of standard reference values of right ventricular longitudinal systolic strain: a systematic review and meta-analysis

Right ventricular function is strongly associated with clinical outcomes in many conditions, and the evaluation of right ventricle (RV) structure and function in patients with cardiopulmonary disorders is an essential component of clinical management. The objective of this study was to determine the normal ranges of right ventricular longitudinal strain (RVLS) measurements derived by two-dimensional (2D) speckle tracking echocardiography (STE) through a systematic review and meta-analysis. A systematic review was performed using PubMed, Cochrane, ClinicalKey, and CINAHL. Search terms covered the concepts of right ventricle, strain, speckle-tracking, and 2D echocardiography with additional filtering for humans and adults over the last decade. The RV four-chamber longitudinal strain (RV4CLS), RV free wall longitudinal strain (RVFWLS), and free wall longitudinal segmental strain values of healthy individuals without cardiopulmonary diseases from 28 studies were assessed. Weighted means were estimated using random-effects models in a meta-analysis. The results show for RV4CLS -24,91%[CI  - 25.94;  - 23.88, I² 98%], for RVFWLS -27.63%[CI  - 28.78;  - 26.48, I² 98%], for basal RVFWLS -26.65%[CI  - 30.57;  - 22.73, I² 99%], mid RVFWLS -27.61%[CI  - 30.99;  - 24.22, I² 99%] and apical RVFWLS -24.54%[CI  - 26.70;  - 22.38, I² 98%]. This systematic review and meta-analysis showed longitudinal strain values of 2D STE derived RV. No clear reference value for RV strain can be distilled from the literature search due to high statistical heterogeneity between the studies. However, all results of our analysis suggest that the lower reference values for RVLS in the current recommendations with a cut-off value of  - 20% is underestimated.

Correlations among noninvasive right ventricular myocardial work indices and the main parameters of systolic and diastolic functions

BACKGROUND

Right ventricular (RV) myocardial work (RVMW) is the latest method used to assess RV function. To date, correlations among RVMW indices and RV systolic and diastolic functions have not been studied.

METHODS

A total of 106 healthy volunteers (median age, 34 years; 46% male) were prospectively enrolled. RVMW indices were measured using the RV pressure-strain loop using specific software. The correlations among RVMW indices and other RV functions were analyzed.

RESULTS

During the multivariate analysis, the RV global work index (RVGWI) was significantly correlated with RV global longitudinal strain (RV GLS) (p < .0001), pulmonary systolic artery pressure (PASP) (p < .0001), and tricuspid annular (TA) plane systolic excursion (TAPSE) (p = .036). RV global constructive work (RVGCW) was correlated with RV GLS (p < .0001) and PASP (p < .0001). RV global wasted work (RVGWW) was correlated with RV GLS (p = .008) and TA isovolumetric acceleration (TA IVA) (p = .008). RV global work efficiency (RVGWE) was correlated with RV GLS (p < .0001) and tissue Doppler (TD) RV myocardial performance index (TD RMPI) (p = .043).

CONCLUSION

RVMW indices showed good correlations with RV myocardial systolic function.

Multimodality Imaging in Arrhythmogenic Right Ventricular Cardiomyopathy

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a rare, heritable myocardial disease associated with the development of ventricular arrhythmias, heart failure, and sudden cardiac death in early adulthood. Multimodality imaging is a central component in the diagnosis and evaluation of ARVC. Diagnostic criteria established by an international task force in 2010 include noninvasive parameters from echocardiography and cardiac magnetic resonance imaging. These criteria identify right ventricular structural abnormalities, chamber and outflow tract dilation, and reduced right ventricular function as features of ARVC. Echocardiography is a widely available and cost-effective technique, and it is often selected for initial evaluation. Beyond fulfillment of diagnostic criteria, features such as abnormal tricuspid annular plane excursion, increased right ventricular basal diameter, and abnormal strain patterns have been described. 3-dimensional echocardiography may also expand opportunities for structural and functional assessment of ARVC. Cardiac magnetic resonance has the ability to assess morphological and functional cardiac features of ARVC and is also a core modality in evaluation, however, tissue characterization of the right ventricle is limited by spatial resolution and low specificity for detection of pathological changes. Nonetheless, the ability of cardiac magnetic resonance to identify left ventricular involvement, offer high negative predictive value, and provide a reproducible structural evaluation of the right ventricle enhance the ability and scope of the modality. In this review, the prognostic significance of multimodality imaging is outlined, including the supplemental value of multidetector computed tomography and nuclear imaging. Strengths and weaknesses of imaging techniques, as well as future direction of multimodality assessment, are also described.

Layer-Specific Global Longitudinal Strain Predicts Arrhythmic Risk in Arrhythmogenic Cardiomyopathy

Background: Arrhythmogenic cardiomyopathy (AC) is a life-threatening disease which predispose to malignant arrhythmias and sudden cardiac death (SCD) in the early stages of the disease. Risk stratification relies on the electrical, genetic, and imaging data. Our study aimed to investigate how myocardial deformation parameters may identify the subjects at risk of known predictors of major ventricular arrhythmias.

Methods: A cohort of 45 subjects with definite or borderline diagnosis of AC was characterized using the advanced transthoracic echocardiography (TTE) and cardiac magnetic resonance (CMR) and divided into the groups according to the potential arrhythmic risk markers, such as non-sustained ventricular tachycardia (NSVT), late gadolinium enhancement (LGE), and genetic status. Layer-specific global longitudinal strain (GLS) by TTE 2D speckle tracking was compared in patients with and without these arrhythmic risk markers.

Results: In this study, 23 (51.1%) patients were men with mean age of 43 ± 16 years. Next-generation sequencing identified a potential pathogenic mutation in 39 (86.7%) patients. Thirty-nine patients presented LGE (73.3%), mostly located at the subepicardial-to-mesocardial layers. A layer-specific-GLS analysis showed worse GLS values at the epicardial and mesocardial layers in the subjects with NSVT and LGE. The epicardial GLS values of −15.4 and −16.1% were the best cut-off values for identifying the individuals with NSVT and LGE, respectively, regardless of left ventricular ejection fraction (LVEF).

Conclusions: The layer-specific GLS assessment identified the subjects with high-risk arrhythmic features in AC, such as NSVT and LGE. An epicardial GLS may emerge as a potential instrument for detecting the subjects at risk of SCD in AC.

Comparison between Nondedicated and Novel Dedicated Tracking Tool for Right Ventricular and Left Atrial Strain

BACKGROUND

Recently, dedicated speckle-tracking solutions for right ventricular (RV) and left atrial (LA) strain assessment have become commercially available. The purpose of this study was to assess the level of agreement between nondedicated (left ventricular [LV] tracking software) and novel dedicated tracking software for RV and LA strain.

METHODS

In 200 patients with various cardiovascular pathologies, we measured global longitudinal strain (GLS), free wall strain (FWS), and segmental values, as well as LA strain during reservoir, conduit, and contraction phases, by using the (1) LV-tracking software and (2) the novel dedicated tracking software for RV or LA strain analysis. Agreement between corresponding measurements obtained with the LV and dedicated RV or LA software was determined by using mean absolute difference (MAD) and Bland-Altman test. The intra- and interobserver reproducibility related to the nondedicated and novel dedicated tracking software was tested in 30 randomly selected subjects.

RESULTS

The dedicated RV-tracking software provided slightly lower strain values without reaching statistical significance. The agreement between software was best for RV GLS (MAD, 2.4 ± 1.8) and significantly poorer for segmental values (MAD ranging from 4.5 ± 3.8 to 5.1 ± 4.0; analysis of variance, P < .05). The intra- and interobserver reproducibility for RV measurements was similar with both software (P > .05 for all parameters). Left atrial mean values showed no statistical difference when obtained with the two tracking tools. The use of LA dedicated tracking software increased significantly the intra- and interobserver reproducibility for LA strain during reservoir and atrial contraction (P < .01 for both).

CONCLUSIONS

Our results suggest that the choice of tracking software does not significantly impact RV strain measurements. Nonetheless, the use of the same tracking software is recommended when performing serial measurements. The use of the dedicated software for LA strain analysis significantly improved the intra- and interobserver reproducibility.

Key role of left ventricular untwisting in endurance cyclists at onset of exercise

The rise in oxygen consumption during the transition from rest to exercise is faster in those who are endurance-trained than those who have sedentary lifestyles, partly due to a more efficient cardiac response. However, data regarding this acute cardiac response in trained individuals are limited to heart rate (HR), stroke volume, and cardiac output. Considering this, we compared cardiac kinetics, including left ventricular (LV) strains and twist/untwist mechanics, between endurance-trained cyclists and their sedentary counterparts. Twenty young, male, trained cyclists and 23 untrained participants aged 18-25 yr performed five similar constant workload exercises on a cyclo-ergometer (target HR: 130 beats/min). During each session, LV myocardial diastolic and systolic linear strains, as well as torsional mechanics, were assessed using speckle-tracking echocardiography. Cardiac function was evaluated every 15 s during the first minute and every 30 s thereafter, until 240 s. Stroke volume increased during the first 30-45 s in both groups but to a significantly greater extent in trained cyclists (31% vs. 24%). Systolic parameters were similar in both groups. Transmitral peak filling velocity and peak filling rate responded faster to exercise and with greater amplitude in trained cyclists. Left ventricular filling pressure was lower in the former, whereas LV relaxation was greater but only at the base of the left ventricle. Basal rotation and peak untwisting rate responded faster and to a greater extent in the cyclists. This study provides new mechanical insights into the key role of LV untwisting in the more efficient acute cardiac response of endurance-trained athletes at onset of exercise.NEW & NOTEWORTHY Our study assessed for the first time, to our knowledge, the kinetics of left ventricular function during the transition from rest to constant-load exercise in endurance-trained subjects. We observed a faster cardiac response in cyclists characterized by a faster response of cardiac output, left ventricular transmitral filling, basal rotation, and untwisting. This study highlighted the key role of left ventricular twisting mechanics in the more efficient acute cardiac response of endurance-trained athletes at onset of exercise.

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.

Multimodality imaging predictors of sudden cardiac death

Sudden cardiac death (SCD) is the worst clinical event occurring in the clinical context of cardiomyopathies. Current guidelines recommend using LV ejection fraction as the only imaging-derived parameter to identify patients who may benefit from ICD implantation in cardiomyopathies with reduced ejection fraction; however, a relevant proportion of high-risk population is left with unmet therapeutic goal. In case of dilated, hypertrophic, or arrhythmogenic cardiomyopathies, there is still a room for more sensitive and specific risk markers for identifying a cluster at higher risk of SCD. In this paper, we reviewed the evidence supporting the use of advanced echocardiography, CMR, and nuclear cardiology for SCD stratification in patients with the most common cardiomyopathies. The added value of these modalities may be explained on the basis of tissue characterization, especially scar detection, a central player in the pathogenesis of arrhythmias. Therefore, integration of these modalities to our everyday clinical practice may help in dealing with the gray zones where current guidelines are still ineffective for patient selection.

Right Ventricular Strain Predicts Structural Disease Progression in Patients With Arrhythmogenic Right Ventricular Cardiomyopathy

Background

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited condition associated with ventricular arrhythmias and myocardial dysfunction; however, limited data exist on identifying patients at highest risk. The purpose of the study was to determine whether measures of right ventricular (RV) dysfunction on echocardiogram including RV strain were predictive of structural disease progression in ARVC.

Methods and Results

A retrospective analysis of serial echocardiograms from 40 patients fulfilling 2010 task force criteria for ARVC was performed to assess structural progression defined by an increase in proximal RV outflow tract dimensions (parasternal short or long axis) or decrease in RV fractional area change. Echocardiograms were analyzed for RV free‐wall peak longitudinal systolic strain using 2‐dimensional speckle tracking. Risk of structural progression and 5‐year change in RV outflow tract measurements were compared with baseline RV strain. Of the 40 ARVC patients, 61% had structural progression with an increase in the mean parasternal short‐axis RV outflow tract dimension from 36.2 to 38.5 mm (P=0.022) and 68% by increase in parasternal long‐axis RV outflow tract dimension from 36.1 to 39.2 mm (P=0.001). RV fractional area change remained stable over time. Baseline RV strain was significantly associated with the risk of structural progression and 5‐year rate of change. Patients with an RV strain more positive than −20% had a higher risk (odds ratio: 18.4; 95% CI, 2.7–125.8; P=0.003) of structural progression.

Conclusions

RV free wall strain is associated with the rate of structural progression in patients with ARVC. It may be a useful marker in determining which patients require closer follow‐up and treatment.

Effects of Familial Mediterranean Fever on Cardiac Functions in Adults: A Cross-Sectional Study Based on Speckle Tracking Echocardiography

Objectives

This study aims to evaluate the right ventricular (RV) and left ventricular (LV) systolic and diastolic functions with speckle tracking echocardiography in addition to routine echocardiographic measurements in adult familial Mediterranean fever (FMF) patients in order to detect cardiac functions.

Patients and methods

Sixty FMF patients (23 males, 37 females; median age 35 years; interquartile range, 26 to 38 years) and 20 healthy subjects (10 males, 10 females; median age 31 years; interquartile range, 25 to 35 years) were included in the study. The diagnosis was established according to the Tel-Hashomer criteria. All patients were using regular colchicine and they were in the attack-free period. Laboratory examinations included complete blood count, creatinine, and inflammatory markers. In addition to routine echocardiographic examination, RV and LV global longitudinal strains were measured and compared.

Results

Erythrocyte sedimentation rate and C-reactive protein values were higher in FMF group. LV global longitudinal strain was similar among the groups. FMF patients had slightly lower early diastolic trans-mitral flow (E) values than controls. As similar as the mitral E flow, tricuspid E flow was slightly lower in FMF groups than controls. RV ejection fraction was similar and in normal ranges among the groups. RV global longitudinal strain was lower in FMF group than controls. RV Myocardial Performance Index (or Tei index) was higher in FMF group.

Conclusion

The present study indicates low values of mean RV global longitudinal strain and higher Tei index in FMF patients. These results suggest that FMF may cause subclinical RV deterioration.

Two-dimensional Echocardiographic Assessment of Myocardial Strain: Important Echocardiographic Parameter Readily Useful in Clinical Field

Echocardiography is the first and is the most-available imaging modality for many cardiovascular diseases, and echocardiographic parameters can give much important information for diagnosis, treatment, and prognostic evaluations. Left ventricular ejection fraction (LVEF) is the most commonly used echocardiographic parameter for left ventricular (LV) systolic function. Although LVEF is used routinely in daily practice, it is calculated from volumetric change without representing true myocardial properties. Recently, strain echocardiography has been used to objectively measure myocardial deformation. Myocardial strain can give accurate information about intrinsic myocardial function, and it can be used to detect early-stage cardiovascular diseases, monitor myocardial changes with specific therapies, differentiate cardiomyopathies, and predict the prognosis of several cardiovascular diseases. Although strain echocardiography has been applied to measure the right ventricle and left atrium, in addition to analyzing the LV, many cardiologists who are not imaging specialists are unaware of its clinical use and importance. Therefore, this review describes the measurement and clinical utility of 2-dimensional strain analysis in various cardiovascular diseases.

Should the septum be included in the assessment of right ventricular longitudinal strain? An ultrasound two-dimensional speckle-tracking stress study

Right ventricular longitudinal strain (RVLS) by 2D speckle-tracking echocardiography (2D-STE) is a useful parameter for assessing systolic function. However, the exact method to perform it is not well defined as some authors evaluate only free wall (FW) segments while others include all six RV segments. To compare the assessment of RVLS at rest and during exercise by these two approaches. Echocardiography was performed on 80 healthy subjects at rest and during exercise. The analysis consisted of standard and 2D-STE assessment of RV global and segmental strain tracing only RVFW and also tracing all six RV segments. At rest, RVLS could be assessed in 78 (feasibility 97.5%) subjects by both methods. However, during exercise, RVLS by RVFW method was feasible in 67 (83.8%) as compared to 74 (92.5%) by RV6S approach. Both at rest and during exercise, RVLS values by the two methods showed excellent correlation (r =  > 0.90). However, RVLS values assessed by RV6S were lower (absolute values) than those by RVFW approach (RV6S vs. RVFW; rest: - 27.0 ± 3.9 vs. - 9.5 ± 3.9, p < 0.001 and exercise: - 30.7 ± 5.2 vs. - 33.3 ± 5.1, p < 0.001). Furthermore, basal strain was higher and apical strain lower (absolute values) by RV6S approach. At rest, reproducibility for RVLS was excellent and similar for the two methods. However, during exercise, reproducibility for RVFW method was poorer, especially at the apex. The two currently described methods for RVLS assessment by 2D-STE demonstrated excellent agreement. However, the RV6S approach seemed to be more feasible and reproducible, particularly during exercise. Moreover, global and segmental strain values are different with both methods and should not be interchanged.

Tricuspid regurgitation and the right ventricle in risk stratification and timing of intervention

Tricuspid regurgitation natural history and treatment remains poorly understood. Right ventricular function is a key factor in determining prognosis, timing for intervention and longer-term outcome. The right ventricle is a thin walled chamber with a predominance of longitudinal fibres and a shared ventricular septum. In health, the low-pressure pulmonary circulation results in a highly compliant RV well equipped to respond to changes in preload but sensitive to even small alterations in afterload. In Part 1 of this article, discussion focuses on key principles of ventricular function assessment and the importance of right ventricular chamber size, volumes and ejection fraction, particularly in risk stratification in tricuspid regurgitation. Part 2 of this article provides an understanding of the causes of tricuspid regurgitation in the contemporary era, with emphasis on key patient groups and their management.

Right ventricular function during exercise in children after heart transplantation

Aims

Right ventricular (RV) dysfunction is a common problem after heart transplant (HTx). In this study, we used semi-supine bicycle ergometry (SSBE) stress echocardiography to evaluate RV systolic and diastolic reserve in paediatric HTx recipients.

Methods and results

Thirty-nine pediatric HTx recipients and 23 controls underwent stepwise SSBE stress echocardiography. Colour tissue doppler imaging (TDI) peak systolic (s') and peak diastolic (e') velocities, myocardial acceleration during isovolumic contraction (IVA), and RV free wall longitudinal strain were measured at incremental heart rates (HR). The relationship with increasing HR was evaluated for each parameter by plotting values at each stage of exercise versus HR using linear and non-linear regression models. At rest, HTx recipients had higher HR with lower TDI velocities (s': 5.4 ± 1.7 vs. 10.4 ± 1.8 cm/s, P < 0.001; e': 6.4 ± 2.2 vs.12 ± 2.4 cm/s, P < 0.001) and RV IVA values (IVA: 1.2 ± 0.4 vs. 1.6 ± 0.8 m/s2, P = 0.04), while RV free wall longitudinal strain was similar between groups. At peak exercise, HR was higher in controls and all measurements of RV function were significantly lower in HTx recipients, except for RV free wall longitudinal strain. When assessing the increase in each parameter vs. HR, the slopes were not significantly different between patients and controls except for IVA, which was lower in HTx recipients.

Conclusion

In pediatric HTx recipients RV systolic and diastolic functional response to exercise is preserved with a normal increase in TDI velocities and strain values with increasing HR. The blunted IVA response possibly indicates a mildly decreased RV contractile response but it requires further investigation.

Strain Analysis of the Right Ventricle Using Two-dimensional Echocardiography

Right ventricular (RV) systolic dysfunction has been identified as an independent prognostic marker of many cardiovascular diseases. However, there are problems in measuring RV systolic function objectively and identification of RV dysfunction using conventional echocardiography. Strain echocardiography is a new imaging modality to measure myocardial deformation. It can measure intrinsic myocardial function and has been used to measure regional and global left ventricular (LV) function. Although the RV has different morphologic characteristics than the LV, strain analysis of the RV is feasible. After strain echocardiography was introduced to measure RV systolic function, it became more popular and was incorporated into recent echocardiographic guidelines. Recent studies showed that RV global longitudinal strain (RVGLS) can be used as an objective index of RV systolic function with prognostic significance. In this review, we discuss RVGLS measurement, normal reference values, and the clinical importance of RVGLS.

Modern Imaging Techniques in Cardiomyopathies

Modern advanced imaging techniques have allowed increasingly more rigorous assessment of the cardiac structure and function of several types of cardiomyopathies. In contemporary cardiology practice, echocardiography and cardiac magnetic resonance imaging are widely used to provide a basic framework in the evaluation and management of cardiomyopathies. Echocardiography is the quintessential imaging technique owing to its unique ability to provide real-time images of the beating heart with good temporal resolution, combined with its noninvasive nature, cost-effectiveness, availability, and portability. Cardiac magnetic resonance imaging provides data that are both complementary and uniquely distinct, thus allowing for insights into the disease process that until recently were not possible. The new catchphrase in the evaluation of cardiomyopathies is multimodality imaging, which is purported to be the efficient integration of various methods of cardiovascular imaging to improve the ability to diagnose, guide therapy, or predict outcomes. It usually involves an integrated approach to the use of echocardiography and cardiac magnetic resonance imaging for the assessment of cardiomyopathies, and, on occasion, single-photon emission computed tomography and such specialized techniques as pyrophosphate scanning.

Added clinical value of applying myocardial deformation imaging to assess right ventricular function

Right heart dysfunction has been found to be a strong prognostic factor predicting adverse outcome in various cardiopulmonary diseases. Conventional echocardiographic measurements can be limited by geometrical assumptions and impaired reproducibility. Speckle tracking-derived strain provides a robust quantification of right ventricular function. It explicitly evaluates myocardial deformation, as opposed to tissue Doppler-derived strain, which is computed from tissue velocity gradients. Right ventricular longitudinal strain provides a sensitive tool for detecting right ventricular dysfunction, even at subclinical levels. Moreover, the longitudinal strain can be applied for prognostic stratification of patients with pulmonary hypertension, pulmonary embolism, and congestive heart failure. Speckle tracking-derived right atrial strain, right ventricular longitudinal strain-derived mechanical dyssynchrony, and three-dimensional echocardiography-derived strain are emerging imaging parameters and methods. Their application in research is paving the way for their clinical use.

Phenotypic expression of ARVC: How 12 lead ECG can predict left or right ventricle involvement. A familiar case series and a review of literature

AIMS

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited heart-muscle disease primarily affecting the right ventricle (RV) and potentially causing sudden death in young people. The natural history of the disease is firstly characterized by a concealed form progressing over a biventricular involvement. Three different cases coming from the same family are presented together with a review of the literature.

METHODS AND RESULTS

Multi-parameter analysis including imaging and electrocardiographic analysis is presented since the first medical referral with follow-up ranging from 11 to 38years. Case 1 presented a typical RV involvement in agreement with the ECG pattern. Case 2 presented a prevalent left ventricular involvement leading from the beginning to a pattern of dilated cardiomyopathy in agreement with his ECG evolution over the years. On the other side, Case 3 came to observation with a typical RV involvement (similar to Case 1) but with ECG evolution of typical left ventricle involvement (similar to Case 2). The genetic analysis showed a mutation in desmoglein-2 (DSG2) gene: p. Arg49His. Comparison between size and localization of ventricular dyskinesia at cardiovascular imaging and the surface 12 lead electrocardiography are proposed.

CONCLUSIONS

ARVC may lead to an extreme phenotypic variability in clinical manifestations even within patients coming from the same family in which ARVC is caused by the same genetic mutation. ECG progression over time reflects disease evolution and in particular cases may anticipate wall motion abnormalities by years.

Evaluation of Tp-e Interval, Tp-e/QT Ratio, and Tp-e/QTc Ratio in Patients with Asymptomatic Arrhythmogenic Right Ventricular Cardiomyopathy

BACKGROUND

Arrhythmogenic right ventricular dysplasia (ARVD) is characterized by progressive replacement of ventricular myocytes with variable amounts of fibrous and adipose tissue. Several studies have suggested that the interval from the peak to the end of the electrocardiographic T wave (Tp-e) may correspond to the transmural dispersion of repolarization and that increased Tp-e interval and Tp-e/QT ratio are associated with malignant ventricular arrhythmias. The aim of this study was to evaluate repolarization dispersion measured from the 12-lead surface electrocardiogram (including Tp-e interval, Tp-e/QT, and Tp-e/QTc ratio) in asymptomatic ARVD patients METHODS: We selected 27 patients with asymptomatic ARVD and 27 age- and gender-match young, healthy volunteers.

RESULTS

Tp-e interval, Tp-e/QT and Tp-e/QTc ratio were also significantly higher in ARVD group compared to the control group (all P < 0.001). There were negative correlation between S global and Tp-e, Tp-e/QT, Tp-e/QTc ration (r = -0.57, P = 0.02; r = -0.85, P = 0.02; r = -0.63, P < 0.01; respectively). There were also negative correlation between Sm global and Tp-e, Tp-e/QT, Tp-e/QTc ration (r = -0.61, P < 0.01; r = -0.67, P < 0.01; r = -0.68, P < 0.01; respectively). Moreover, Em global were negative correlation between Tp-e, Tp-e/QT, and Tp-e/QTc (r = - 0.64, P < 0.001, r = - 0.75, P < 0.01; r = -0,69, P < 0.01; respectively) CONCLUSION: In conclusion, we have presented strong evidence suggesting that Tp-e interval, Tp-e/QT ratio, and Tp-e/QTc ratio were increased in asymptomatic ARVD patients.

A meta-analysis for echocardiographic assessment of right ventricular structure and function in ARVC

INTRODUCTION

Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) is an inherited pathology that can increase the risk of sudden death. Current Task Force Criteria for echocardiographic diagnosis do not include new, regional assessment tools which may be relevant in a phenotypically diverse disease. We adopted a systematic review and meta-analysis approach to highlight echocardiographic indices that differentiated ARVC patients and healthy controls.

METHODS

Data was extracted and analysed from prospective trials that employed a case-control design meeting strict inclusion and exclusion as well as a-priori quality criteria. Structural indices included proximal RV outflow tract(RVOT1) and RV diastolic area(RVDarea). Functional indices included RV fractional area change (RVFAC), Tricuspid Annular Systolic Excursion(TAPSE), peak systolic and early diastolic myocardial velocities (S' and E' respectively) and myocardial strain.

RESULTS

Patients with ARVC had larger RVOT1 (mean  SD; 34 vs. 28 mm P<0.001) and RVDarea (23 vs. 18 cm2 P<0.001) compared to healthy controls. ARVC patients also had lower RVFAC (38 vs. 46 % P<0.001), TAPSE(17 vs. 23 mm P<0.001), S' (9 vs. 12 cm.s-1 P<0.001), E' (9 vs. 13 cm.s-1 P<0.001) and myocardial strain (-17 vs. -30% P<0.001).

CONCLUSION

The data from this meta-analysis support current Task Force criteria for the diagnosis of ARVC. In addition, other RV measures that reflect the complex geometry and function in ARVC clearly differentiated between ARVC and healthy controls and may provide additional diagnostic and management value. We recommend that future working groups consider this data when proposing new / revised criteria for the echocardiographic diagnosis of ARVC.

Tissue Tracking Technology for Assessing Cardiac Mechanics: Principles, Normal Values, and Clinical Applications

Tissue tracking technologies such as speckle tracking echocardiography and feature tracking cardiac magnetic resonance have enhanced the noninvasive assessment of myocardial deformation in clinical research and clinical practice. The widespread enthusiasm for using tissue tracking techniques in research and clinical practice stems from the ready applicability of these technologies to routine echocardiographic or cardiac magnetic resonance images. The technology is common to both modalities, and derived parameters to describe myocardial mechanics are the similar, albeit with different accuracies. We provide an overview of the normal values and reproducibility of the clinically applicable parameters, together with their clinical validation. The use of these technologies in different clinical scenarios, and the additive value to current imaging diagnostics are discussed.

Utility of speckle tracking echocardiography imaging in patients with asymptomatic and symptomatic arrhythmogenic right ventricular cardiomyopathy

BACKGROUND

Arrhythmogenic right ventricular dysplasia (ARVD) is characterized by the progressive replacement of ventricular myocytes with variable amounts of fibrous and adipose tissue. Several studies have suggested that speckle tracking echocardiographic (STE) parameters such as strain (S) and strain rate (SR) may prove useful in the early detection of right ventricular (RV) dysfunction. Therefore, the aim of this study was to evaluate RV myocardial function using the STE method in both asymptomatic and symptomatic patients with ARVD and to assess its potential role in the differential diagnosis of these two presentations.

METHODS

We recruited 34 patients with ARVD. Seventeen patients were symptomatic, and seventeen were asymptomatic.

RESULTS

The RV free wall global longitudinal S and SR were significantly lower in symptomatic patients with ARVD than in asymptomatic patients. According to a cutoff value of 1.35 per seconds for RV global SR, the sensitivity and specificity for predicting ARVD were 88% and 77%, respectively. According to a cutoff value of 17.3% for RV S, the sensitivity and specificity for predicting ARVD were 82% and 77%, respectively.

CONCLUSION

In conclusion, we present strong evidence that STE-derived global S and SR in the RV free wall are decreased in symptomatic patients with ARVD compared with asymptomatic patients.

Arrhythmogenic Cardiomyopathy: Electrical and Structural Phenotypes

This overview gives an update on the molecular mechanisms, clinical manifestations, diagnosis and therapy of arrhythmogenic cardiomyopathy (ACM). ACM is mostly hereditary and associated with mutations in genes encoding proteins of the intercalated disc. Three subtypes have been proposed: the classical right-dominant subtype generally referred to as ARVC/D, biventricular forms with early biventricular involvement and left-dominant subtypes with predominant LV involvement. Typical symptoms include palpitations, arrhythmic (pre)syncope and sudden cardiac arrest due to ventricular arrhythmias, which typically occur in athletes. At later stages, heart failure may occur. Diagnosis is established with the 2010 Task Force Criteria (TFC). Modern imaging tools are crucial for ACM diagnosis, including both echocardiography and cardiac magnetic resonance imaging for detecting functional and structural alternations. Of note, structural findings often become visible after electrical alterations, such as premature ventricular beats, ventricular fibrillation (VF) and ventricular tachycardia (VT). 12-lead ECG is important to assess for depolarisation and repolarisation abnormalities, including T-wave inversions as the most common ECG abnormality. Family history and the detection of causative mutations, mostly affecting the desmosome, have been incorporated in the TFC, and stress the importance of cascade family screening. Differential diagnoses include idiopathic right ventricular outflow tract (RVOT) VT, sarcoidosis, congenital heart disease, myocarditis, dilated cardiomyopathy, athlete's heart, Brugada syndrome and RV infarction. Therapeutic strategies include restriction from endurance and competitive sports, β-blockers, antiarrhythmic drugs, heart failure medication, implantable cardioverter-defibrillators and endocardial/epicardial catheter ablation.

Noninvasive Multimodality Imaging in ARVD/C

Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is a familial cardiomyopathy resulting in progressive right ventricular (RV) dysfunction and malignant ventricular arrhythmias. Although ARVD/C is generally considered an inherited cardiomyopathy, the arrhythmogenic nature of the disease is striking. Affected individuals typically present in the second to fourth decade of life with arrhythmias originating from the right ventricle. Over the past decade, pathogenic ARVD/C-causing mutations have been identified in 5 genes encoding the cardiac desmosome. Disruption of the desmosomal connection system between cardiomyocytes may be represented structurally by ventricular enlargement, global or regional contraction abnormalities, RV aneurysms, or fibrofatty replacement. These abnormalities are typically observed in predilection areas, including the subtricuspid region, basal RV free wall, and left ventricular posterolateral wall. As such, structural and functional abnormalities on cardiac imaging constitute an important diagnostic criterion for the disease. This paper discusses the current status and role of echocardiography, cardiac magnetic resonance imaging, and computed tomography for suspected ARVD/C.

Strain and strain rate: An emerging technology in the perioperative period

Newer noninvasive parameters are being used for perioperative detection of myocardial ischaemia. TDI and global strain rate are some of these parameters. TDI signal is a modification of the routine Doppler flow signal. It is obtained by using thresholding and filtering algorithms that reject echoes originating from the blood pool (by-passing the high pass filter). Set-Up of the machine by activating the TDI function allows decreasing the system gain using a low pass filter and eliminates the signal produced by blood flow. Doppler shift obtained from myocardial tissue motion are of higher amplitudes (reflectivity 40 dB higher) and move about 10 times slower than blood (velocity range: 0.06 to 0.24 m/s). Speckle tracking echocardiography (tissue tracking, 2D strain) utilizes routine gray-scale 2D echo images to calculate myocardial strain. Interactions of ultrasound with myocardium result in reflection and scattering. These interactions generate a finely gray-shaded, speckled pattern (acoustic marker). This speckled pattern is unique for each myocardial region and relatively stable throughout the cardiac cycle. Spatial and temporal image processing of acoustic speckles in both 2D and 3D allows for the calculation of myocardial velocity, strain, and Strain rate.

Role of strain imaging in right heart disease: a comprehensive review

Advances in the imaging techniques of the heart have fueled the interest in understanding of right heart pathology. Recently, speckle tracking echocardiography has shown to aid in understanding various right heart diseases and better management. Its role is well established in diagnosing right heart failure, pulmonary artery hypertension, arrhythmogenic right ventricular dysplasia and congenital heart disease. We review the basic mechanics of speckle tracking and analyze its role in various right heart conditions.

Arrhythmogenic ventricular cardiomyopathy: A paradigm shift from right to biventricular disease

Arrhythmogenic ventricular cardiomyopathy (AVC) is generally referred to as arrhythmogenic right ventricular (RV) cardiomyopathy/dysplasia and constitutes an inherited cardiomyopathy. Affected patients may succumb to sudden cardiac death (SCD), ventricular tachyarrhythmias (VTA) and heart failure. Genetic studies have identified causative mutations in genes encoding proteins of the intercalated disk that lead to reduced myocardial electro-mechanical stability. The term arrhythmogenic RV cardiomyopathy is somewhat misleading as biventricular involvement or isolated left ventricular (LV) involvement may be present and thus a broader term such as AVC should be preferred. The diagnosis is established on a point score basis according to the revised 2010 task force criteria utilizing imaging modalities, demonstrating fibrous replacement through biopsy, electrocardiographic abnormalities, ventricular arrhythmias and a positive family history including identification of genetic mutations. Although several risk factors for SCD such as previous cardiac arrest, syncope, documented VTA, severe RV/LV dysfunction and young age at manifestation have been identified, risk stratification still needs improvement, especially in asymptomatic family members. Particularly, the role of genetic testing and environmental factors has to be further elucidated. Therapeutic interventions include restriction from physical exercise, beta-blockers, sotalol, amiodarone, implantable cardioverter-defibrillators and catheter ablation. Life-long follow-up is warranted in symptomatic patients, but also asymptomatic carriers of pathogenic mutations.