Normal values and reference ranges for left atrial strain by speckle-tracking echocardiography: the Copenhagen City Heart Study

Left Atrial Strain to Predict Postoperative Atrial Fibrillation in Patients Undergoing Off-pump Coronary Artery Bypass Graft

OBJECTIVE

Postoperative atrial fibrillation (POAF) is associated with increased morbidity, mortality, and length of hospital stay. The objective of this study was to assess the utility of left atrial strain (LAS) to predict POAF in patients undergoing off-pump coronary artery bypass grafting (OPCABG).

DESIGN

Retrospective observational study.

SETTING

Tertiary care hospital.

PARTICIPANTS

103 patients undergoing OPCABG.

INTERVENTIONS

None.

MEASUREMENTS AND RESULTS

In addition to comprehensive transthoracic echocardiography, LAS was measured for reservoir (R), conduction (CD), and contraction (CT) components. POAF was defined as new electrocardiographic evidence of AF requiring treatment. Logistic regression was done to assess factors associated with POAF. The diagnostic accuracy of variables in predicting POAF was assessed by receiver operating characteristic analysis. POAF was documented in 24 (23.3%) patients. There was no difference in ejection fraction, average global longitudinal strain, or proportion of left ventricular diastolic dysfunction grades between patients with POAF and patients without POAF. All three components of LAS: LAS R (19.2 ± 4.7 v 23.5 ± 4.8, p < 0.001), LAS CD (8.9 ± 3.7 v 12.3 ± 4.8, p = 0.1), and LAS CT (10.3 ± 3.9 v 12.1 ± 4.1, p = 0.04), were significantly lower among patients with POAF compared with patients without POAF, respectively. According to univariate analysis, all components of LAS were statistically significant predictors of POAF. In multivariate analysis, only age (odds ratio = 1.08, p = 0.025) and LAS R (odds ratio = 0.84, p = 0.004) were independently associated with POAF. LAS R was a better predictor of POAF, with an area under the curve (AUC) of 0.758, than LAS CD (AUC = 0.67) and LAS CT (AUC = 0.62). LAS R had an optimal cutoff of 23% with sensitivity of 95.8% (confidence interval: 78.9-99.9%) and specificity of 49.4% (37.9-60.9%) to predict POAF.

CONCLUSIONS

LAS R is a significant predictor of POAF, and its use can be recommended for screening of OPCABG patients at high risk of POAF.

Association of central arterial stiffness with atrial myopathy: the Atherosclerosis Risk in Communities (ARIC) study

Atrial myopathy-defined as abnormal left atrial (LA) size and function-is associated with an increased risk of atrial fibrillation, heart failure, and dementia. Central arterial stiffness is associated with increased atrial afterload and fibrosis and may be a risk factor for atrial myopathy. We examined the association of carotid-femoral pulse wave velocity (cfPWV) with LA function and assessed potential causal relationships. We included 2825 Atherosclerosis Risk in Communities (ARIC) study participants from Visit 5 (2011-2013). cfPWV was related to echocardiographic LA function continuously per 1-SD and categorically in quartiles. Mendelian randomization (MR) analysis was performed using U.K. Biobank-derived genetic variants associated with arterial stiffness index and cardiac magnetic resonance measures of LA function. When analyzed per SD increment (297.6 cm/s), higher cfPWV was significantly associated with lower LA reservoir and conduit strain (β = -0.53%, 95% CI [-0.81, -0.25] and β = -0.46%, 95% CI [-0.68, -0.25], respectively) after adjusting for demographics, clinical characteristics, systolic blood pressure, and left ventricular (LV) morphology and function. In MR analyses there was a non-significant inverse association of arterial stiffness index with LA total, passive, and active emptying fractions. Higher cfPWV is associated with lower LA reservoir and conduit strain, independent of systolic blood pressure and LV morphology and function. No evidence for a causal relationship between arterial stiffness index and alterations in LA function was found. Future studies should examine the prospective association of central arterial stiffness with LA function alterations.

Left atrial strain in patients with β-thalassemia major: a cross-sectional CMR study

OBJECTIVES

The aim of this cross-sectional study was to investigate the association of left atrial (LA) strain parameters with demographics, clinical data, cardiovascular magnetic resonance (CMR) findings, and cardiac complications (heart failure and arrhythmias) in a cohort of patients with β-thalassemia major (β-TM).

MATERIALS AND METHODS

We considered 264 β-TM patients (133 females, 36.79 ± 11.95 years) consecutively enrolled in the Extension-Myocardial Iron Overload in Thalassemia (E-MIOT) project. Moreover, we included 35 sex- and age-matched healthy controls (14 females, mean age 37.36 ± 17.52 years). Reservoir, conduit, and booster LA functions were analysed by CMR feature tracking using dedicated software.

RESULTS

Compared to the healthy control group, β-TM patients demonstrated lower LA reservoir strain and booster strains, as well as LA reservoir and booster strain rates. However, no differences were found in LA conduit deformation parameters. In β-TM patients, ageing, sex, and left ventricle (LV) volume indexes were independent determinants of LA strain parameters. The number of segments with late gadolinium enhancement (LGE) significantly correlated with all LA strain parameters, with the exception of the LA conduit rate. Patients with cardiac complications exhibited significantly impaired strain parameters compared to patients without cardiac complications.

CONCLUSION

In patients with β-TM, LA strain parameters were impaired compared to control subjects, and they exhibited a significant correlation with the number of LV segments with LGE. Furthermore, patients with cardiac complications had impaired left atrial strain parameters. Clinical relevance statement In patients with β-thalassemia major, left atrial strain parameters were impaired compared to control subjects and emerged as a sensitive marker of cardiac complications, stronger than cardiac iron levels.

KEY POINTS

• Compared to healthy subjects, β-thalassemia major patients demonstrated significantly lower left atrial reservoir strain and booster strains, as well as left atrial reservoir and booster strain rates. • In β-thalassemia major, ageing, sex, and left ventricular volume indexes were independent determinants of left atrial strain parameters, while left atrial strain parameters were not correlated with myocardial iron overload. • An independent association between reduced left atrial strain parameters and a history of cardiac complications was found in β-thalassemia major patients.

Atrial cardiomyopathy revisited-evolution of a concept: a clinical consensus statement of the European Heart Rhythm Association (EHRA) of the ESC, the Heart Rhythm Society (HRS), the Asian Pacific Heart Rhythm Society (APHRS), and the Latin American Heart Rhythm Society (LAHRS)

AIMS

The concept of "atrial cardiomyopathy" (AtCM) had been percolating through the literature since its first mention in 1972. Since then, publications using the term were sporadic until the decision was made to convene an expert working group with representation from four multinational arrhythmia organizations to prepare a consensus document on atrial cardiomyopathy in 2016 (EHRA/HRS/APHRS/SOLAECE expert consensus on atrial cardiomyopathies: definition, characterization, and clinical implication). Subsequently, publications on AtCM have increased progressively.

METHODS AND RESULTS

The present consensus document elaborates the 2016 AtCM document further to implement a simple AtCM staging system (AtCM stages 1-3) by integrating biomarkers, atrial geometry, and electrophysiological changes. However, the proposed AtCM staging needs clinical validation. Importantly, it is clearly stated that the presence of AtCM might serve as a substrate for the development of atrial fibrillation (AF) and AF may accelerates AtCM substantially, but AtCM per se needs to be viewed as a separate entity.

CONCLUSION

Thus, the present document serves as a clinical consensus statement of the European Heart Rhythm Association (EHRA) of the ESC, the Heart Rhythm Society (HRS), the Asian Pacific Heart Rhythm Society (APHRS), and the Latin American Heart Rhythm Society (LAHRS) to contribute to the evolution of the AtCM concept.

Echocardiographic assessment of atrial, ventricular, and valvular function in patients with atrial fibrillation-an expert proposal by the german working group of cardiovascular ultrasound

Echocardiography in patients with atrial fibrillation is challenging due to the varying heart rate. Thus, the topic of this expert proposal focuses on an obvious gap in the current recommendations about diagnosis and treatment of atrial fibrillation (AF)-the peculiarities and difficulties of echocardiographic imaging. The assessment of systolic and diastolic function-especially in combination with valvular heart diseases-by echocardiography can basically be done by averaging the results of echocardiographic measurements of the respective parameters or by the index beat approach, which uses a representative cardiac cycle for measurement. Therefore, a distinction must be made between the functionally relevant status, which is characterized by the averaging method, and the best possible hemodynamic status, which is achieved with the most optimal left ventricular (LV) filling according to the index beat method with longer previous RR intervals. This proposal focuses on left atrial and left ventricular function and deliberately excludes problems of echocardiography when assessing left atrial appendage in terms of its complexity. Echocardiography of the left atrial appendage is therefore reserved for its own expert proposal.

Atrial Strain and Strain Rate in a General Population: Do These Measures Improve the Assessment of Elevated NT-proBNP Levels?

Background

Noninvasive assessment of elevated filling pressure in the left ventricle (LV) remains an unresolved problem. Of the many echocardiographic parameters used to evaluate diastolic pressure, the left atrial strain and strain rate (LA S/SR) have shown promise in clinical settings. However, only a few previous studies have evaluated LA S/SR in larger populations.

Methods

A total of 2033 participants from Norwegian (Tromsø 7) and Russian (Know Your Heart) population studies, equally distributed by age and sex, underwent echocardiography, including atrial and ventricular S/SR and NT-proBNP measurements. Of these, 1069 were identified as healthy (without hypertension (HT), atrial fibrillation (AF), or structural cardiac disease) and were used to define the age- and sex-adjusted normal ranges of LA S/SR. Furthermore, the total study population was divided into groups according to ejection fraction (EF) ≥50%, EF <50%, and AF. In each group, uni- and multiple regression and receiver operating characteristic curve analyses were performed to test LA and LV functional parameters as potential indicators of NT-proBNP levels above 250 ng/ml.

Results

The mean LA S/SR values in this study were higher than those in previous large studies, whereas the lower references were comparable. In normal hearts, atrial total strain (ATS) and mitral valve E deceleration time (MV DT) were independent factors indicating elevated NT-proBNP levels, whereas in hearts with reduced EFs, the independent indicators were peak atrial contraction strain (PACS) and LV stroke volume. The areas under the curve for these significant indicators to discriminate elevated NT-proBNP levels were 0.639 (95% confidence interval (CI): 0.577-0.701) for normal EF and 0.805 (CI: 0.675-0.935) for reduced EF.

Conclusion

The results confirm good intrastudy reproducibility, with mean values in the upper range of previous meta-analyses. In the future, automated border-detection algorithms may be able to generate highly reproducible normal values. Furthermore, the study showed atrial S/SR as an additional indicator of elevated NT-proBNP levels in the general population, demonstrating the incremental value of both ATS and PACS in addition to conventional and ventricular strain echocardiography. Thus, the LA S/SR may be regarded as an important addition to the multiparametric approach used for evaluating LV filling.

Current and Clinically Relevant Echocardiographic Parameters to Analyze Left Atrial Function

The evaluation of the left atrial (LA) size using the LA volume index (LAVI) is clinically relevant due to its prognostic significance in various conditions. Nonetheless, adding a LA function assessment to the LAVI provides further clinical and prognostic information in different cardiovascular (CV) diseases. The assessment of LA function by echocardiography primarily includes volumetric measurements (LA ejection fraction [LAEF]), tissue Doppler imaging (TDI) (mitral annular late diastolic velocity [a']), and speckle-tracking methods, such as LA longitudinal reservoir strain (LA strain). This review analyzes and discusses the current medical evidence and potential clinical usefulness of these different methods to analyze LA function.

Left atrial strain in patients after arterial switch operation for transposition of the great arteries

BACKGROUND

Left atrial (LA) strain, comprising LA reservoir, conduit and contractile function could add mechanistic information of patients after arterial switch operation (ASO) for transposition of the great arteries (TGA). ASO patients might have abnormal ventriculoarterial coupling, which makes them vulnerable to left ventricle (LV) dysfunction and results in reduced exercise capacity. This explorative study aimed to evaluate the relation between LA strain, atrial size, ventricular function, and exercise data obtained by cardiopulmonary exercise testing (CPET).

METHODS

In a cohort of 44 patients (71% male, mean age 25 ± 4 years) LA strain was measured using transthoracic speckle-tracking echocardiography. Further assessment involved standard echocardiography, CPET evaluation, and blood sampling. LA strain values were compared to normal values. Correlations were calculated. Regression analysis with all strain variables to the CPET data was performed.

RESULTS

LA reservoir, conduit and contractile strain were normal in 30%, 89% and 50% of the patients, respectively. LA reservoir/contractile strain correlated to LV ejection fraction (ρ 0.310/-0.159, respectively) and LA reservoir/conduit strain correlated to the LA volume index (ρ 0.336/-0.357, respectively). None of the individual LA strain parameters were associated with the CPET variables. In multivariate regression analysis, LA contractile strain was significantly associated with the percentage of predicted maximal heart rate (β - 2.555).

CONCLUSIONS

These data suggest that in TGA patients after ASO repair LA strain is impaired and correlates with LA size and LV function. However, impaired LA strain wasn't associated with the standard CPET parameters. As such, clinical significance needs to be further unravelled.

Left atrium as key player and essential biomarker in heart failure

This article reviews roles of the left atrium as regulator of left ventricular filling, as compensatory reserve in left ventricular dysfunction and as diagnostic marker in patients with cardiovascular disorders. Application of novel imaging tools to assess left atrial function and their integration with conventional clinical methods are discussed. This includes a review of clinical applications of left atrial strain as a method to quantify the reservoir and booster pump components of left atrial function. Emerging methods for assessing left atrial wall stiffness and active work by pressure-strain loop analysis are discussed. Recommendations for how to apply left atrial strain in clinical routine to diagnose elevated left ventricular filling pressure are provided. Furthermore, a role for left atrial strain in the diagnostic work-up in patients suspected of pre-capillary pulmonary hypertension is proposed. The article also reviews how to implement parameters of atrial structure and function in clinical routine as recommended by recent international guidelines for imaging of heart failure.

Ischemic stroke and the emerging role of left atrial function

INTRODUCTION

Ischemic stroke is a leading cause of morbidity and mortality worldwide. Emerging evidence suggests that left atrial (LA) dysfunction could play a role in the pathophysiology of ischemic stroke, as a possible contributor and as a predictive biomarker.

AREAS COVERED

This narrative review details the intricate relationship between LA function, atrial fibrillation (AF), and ischemic stroke. We discuss imaging techniques used to assess LA function, the mechanisms by which impaired LA function may contribute to stroke, and its potential as a prognostic marker of stroke.

EXPERT OPINION

There is a lack of evidence-based treatments of LA dysfunction in both primary and secondary stroke prevention. This is partly due to the lack of a practical clinical definition and unanswered questions concerning the clinical implications of LA dysfunction in patients without AF. Until such questions are resolved, addressing well-known cardiovascular risk factors, like hypertension and obesity, should be prioritized for preventing AF and ischemic stroke. These risk factors are closely tied to atrial remodeling, emphasizing the importance of targeting primary modifiable factors for preventing future morbidity and mortality.

Left Atrial Mechanics Following Preeclamptic Pregnancy

BACKGROUND

Preterm preeclampsia is a pregnancy complication associated with myocardial dysfunction and premature cardiovascular disease morbidity and mortality. Left atrial (LA) strain is a noninvasive index of left ventricular end diastolic pressure and an early marker of heart failure risk. This study aimed to evaluate LA strain during the postpartum period in participants with and without preterm preeclampsia and to assess whether this varied in the presence of hypertension, cardiac dysfunction or both.

METHODS

In this longitudinal cohort study, 321 women from 28 hospitals with preterm preeclampsia (cases) underwent cardiovascular assessment 6 months postpartum. This is a secondary analysis of the PHOEBE study (ISRCTN01879376). An uncomplicated pregnancy control group (n=30) was recruited from a single center for comparison. A full cross-sectional transthoracic echocardiogram was performed, and from these images, the myocardial strain of the left atrium, including reservoir, conduit, and contractile strain, as well as LA stiffness, were calculated.

RESULTS

At 6 months postpartum, compared with controls, prior preeclampsia was associated with a significantly attenuated LA reservoir, conduit, and contractile strain, as well as increased LA stiffness (all P<0.001). LA strain was further reduced in preeclamptic women who had and had not developed hypertension, systolic, or diastolic dysfunction at 6 months postpartum (all P<0.05).

CONCLUSIONS

LA mechanics were significantly attenuated at 6 months postpartum in participants with preterm preeclampsia, whether or not they remained hypertensive or had evidence of ventricular dysfunction. Further studies are needed to determine whether postnatal LA strain may identify women at greater risk for future cardiovascular disease.

Potential Role of Left Atrial Strain to Predict Atrial Fibrillation Recurrence after Catheter Ablation Therapy: A Clinical and Systematic Review

Pulmonary vein isolation (PVI) with catheter ablation (CA) represents an effective therapy for atrial fibrillation (AF). Unfortunately, it is still not exempt from severe complications. The balance of risks and benefits should be assessed, and a patient-tailored approach is desirable. So far, several clinical and cardiac imaging parameters have been evaluated to investigate pre- and post-procedural features that could help clinicians in the selection of patients at high risk of a poor outcome after CA. This clinical and systematic review analyses the potential role of new LA parameters, such as LA reservoir strain, to predict AF recurrence after CA therapy. Notably, LA reservoir strain gains substantial clinical importance in patients with paroxysmal AF and when a low CHADS2-VASc score is retrieved. LA reservoir strain provides data concerning the risk of AF recurrence after PVI and, thus, in the management of long-term medical therapy in this patient's group.

Left atrial strain in neonates with congenital diaphragmatic hernia and length of stay in pediatric intensive care unit

Introduction

The role of cardiac left ventricle (LV) dysfunction in children with congenital diaphragmatic hernia (CDH) has gained increasing attention. The hernia allows abdominal mass to enter thorax and subsequently both dislocating and compressing the heart. The pressure on vessels and myocardium alters blood flow and may interfere with normal development of the LV. A dysfunctional LV is concerning and impacts the complex pathophysiology of CDH. Hence, assessing both the systolic and diastolic LV function in the newborn with CDH is important, and it may add value for medical treatment and prognostic factors as length of stay (LOS) in pediatric intensive care unit (PICU). LV strain is considered an early marker of systolic dysfunction used in the pediatric population. Left atrial (LA) strain is an echocardiographic marker of LV diastolic dysfunction used in the adult population. When filling pressure of the LV increases, the strain of the atrial wall is decreased. We hypothesized that reduced LA strain and LV strain are correlated with the LOS in the PICU of newborns with CDH.

Methods

This retrospective observational cohort study included data of 55 children born with CDH between 2018 and 2020 and treated at Karolinska University Hospital, Sweden. Overall, 46 parents provided consent. Echocardiograms were performed in 35 children <72 h after birth. The LA reservoir strain (LASr), LV global longitudinal strain, LV dimensions, and direction of blood flow through the patent foramen ovale (PFO) were retrospectively assessed using the echocardiograms.

Results

Children with LASr <33% (n = 27) had longer stays in the PICU than children with LA strain ≥33% (n = 8) (mean: 20.8 vs. 8.6 days; p < 0.002). The LASr was correlated with the LOS in the PICU (correlation coefficient: -0.378; p = 0.025). The LV dimension was correlated with the LOS (correlation coefficient: -0.546; p = 0.01). However, LV strain was not correlated to LOS.

Conclusion

Newborns with CDH and a lower LASr (<33%) had longer stays in the PICU than children with LASr ≥33%. LASr is a feasible echocardiographic marker of diastolic LV dysfunction in newborns with CDH and may indicate the severity of the condition.

Left atrial function in middle-aged men and women with and without paroxysmal atrial fibrillation: Data from the Akershus Cardiac Examination (ACE) 1950 study

PURPOSE

To assess left atrial (LA) function in individuals with known paroxysmal atrial fibrillation (AF) compared with healthy and nonhealthy individuals without atrial fibrillation.

METHODS

The Akershus Cardiac Examination 1950 Study included 3,706 individuals all born in 1950. LA strain assessment of reservoir (LASr), conduit (LAScd) and contractile (LASct) functions were performed in all participants by investigators blinded to clinical data. Participants with cardiovascular disease, obesity, diabetes, pulmonary or renal disease were defined as nonhealthy, and those without as healthy. Patients with paroxysmal AF were identified through medical history and ECG documentation.

RESULTS

LA strain assessment was feasible in 3,229 (87%) of the participants (50% women). The healthy group (n = 758) had significantly higher LASr and LAScd than the nonhealthy (n = 2,376), but LASct was similar between the groups. Participants with paroxysmal AF had significantly lower values of all strain parameters than the other groups. Multivariable logistic regression showed a significantly reduced probability of having AF per standard deviation increase in LASr and LASct. A nonlinear restricted cubic spline model fitted better with the association of LASr with paroxysmal AF than the linear model, and LA strain values below the population mean associated with an increased probability of having AF, but for values above the population mean no such association was present.

CONCLUSION

Compared to participants without AF, those with known paroxysmal AF had significantly lower values of all LA strain parameters during sinus rhythm. Lower values of LA strain were associated with a significantly increased probability of having AF.

Patient-specific left atrium contraction quantification associated with atrial fibrillation: A region-based approach

BACKGROUND AND OBJECTIVES

Atrial fibrillation (AF) is a widespread cardiac arrhythmia that significantly impacts heart function. AF disrupts atrial mechanical contraction, leading to irregular, uncoordinated, and slow blood flow inside the atria which favors the formation of clots, primarily within the left atrium (LA). A standardized region-based analysis of the LA is missing, and there is not even any consensus about how to define the LA regions. In this study we propose an automatic approach for regionalizing the LA into segments to provide a comprehensive 3D region-based LA contraction assessment. LA global and regional contraction were quantified in control subjects and in AF patients to describe mechanical abnormalities associated with AF.

METHODS

The proposed automatic approach for LA regionalization was tested in thirteen control subjects and seventeen AF patients. After dividing LA into standard regions, we evaluated the global and regional mechanical function by measuring LA contraction parameters, such as regional volume, global and regional strains, regional wall motion and regional shortening fraction.

RESULTS

LA regionalization was successful in all study subjects. In the AF group compared with control subjects, results showed: a global impairment of LA contraction which appeared more pronounced along radial and circumferential direction; a regional impairment of radial strain which was more pronounced in septal, inferior, and lateral regions suggesting a greater reduction in mechanical efficiency in these regions in comparison to the posterior and anterior ones.

CONCLUSION

An automatic approach for LA regionalization was proposed. The regionalization method was proved to be robust with several LA anatomical variations and able to characterize contraction changes associated with AF.

Increased epicardial adipose tissue is associated with left atrial mechanical dysfunction in patients with heart failure with mildly reduced and preserved ejection fraction

INTRODUCTION

Heart failure (HF) with mildly reduced and preserved ejection fraction (HFmrEF/HFpEF) is often accompanied by atrial dysfunction. It has been suggested that specific ectopic fat depots, such as epicardial adipose tissue (EAT), may directly influence the myocardial cells and, therefore, be involved in the pathophysiology of atrial mechanical dysfunction. In this study, we aimed to investigate the association between EAT and left atrial (LA) mechanical dysfunction.

METHODS AND RESULTS

In total, 82 patients with symptomatic HF and left ventricular ejection fraction > 40% were prospectively enrolled. All patients underwent CMR while in sinus rhythm. LA mechanical dysfunction was defined as the presence of LA end-systolic volume index > 52 mL/m2 and LA reservoir strain < 23%. EAT volume was indexed for body surface area. Mean age was 69 ± 10 years, 42 (51%) were women and mean body mass index (BMI) was 29 ± 6 kg/m2. Mean LVEF was 55 ± 9% and 34 (41%) patients had LA mechanical dysfunction. In patients with LA mechanical dysfunction, the EAT volume was significantly higher than in patients without LA mechanical dysfunction (90 vs 105 mL/m2, p = 0.02) while BMI was similar. In multivariable logistic regression analyses, increased EAT remained significantly associated with LA mechanical dysfunction (OR 1.31, 95% CI 1.03-1.66, p = 0.03).

CONCLUSION

Increased EAT was associated with LA mechanical dysfunction in patients with HFmrEF and HFpEF. Further research is needed to elucidate the exact mechanisms that underlie this association.

Changes in left atrial function following two regimens of combined exercise training in patients with ischemic cardiomyopathy: a pilot study

Purpose

Left atrial dysfunction has shown to play a prognostic role in patients with ischemic cardiomyopathy (ICM) and is becoming a therapeutic target for pharmacological and non-pharmacological interventions. The effects of exercise training on the atrial function in patients with ICM have been poorly investigated. In the present study, we assessed the effects of a 12-week combined training (CT) program on the left atrial function in patients with ICM.

Methods

We enlisted a total of 45 clinically stable patients and randomly assigned them to one of the following three groups: 15 to a supervised CT with low-frequency sessions (twice per week) (CTLF); 15 to a supervised CT with high-frequency sessions (thrice per week) (CTHF); and 15 to a control group following contemporary preventive exercise guidelines at home. At baseline and 12 weeks, all patients underwent a symptom-limited exercise test and echocardiography. The training included aerobic continuous exercise and resistance exercise. The analysis of variance (ANOVA) was used to compare within- and inter-group changes.

Results

At 12 weeks, the CTLF and CTHF groups showed a similar increase in the duration of the ergometric test compared with the control (ANOVA p < 0.001). The peak atrial longitudinal strain significantly increased in the CTHF group, while it was unchanged in the CTLF and control groups (ANOVA p = 0.003). The peak atrial contraction strain presented a significant improvement in the CTHF group compared with the CTLF and control groups. The left ventricular global longitudinal strain significantly increased in both the CTHF and the CTLF groups compared with the control group (ANOVA p = 0.017). The systolic blood pressure decreased in the CTHF and CTLF groups, while it was unchanged in the control group. There were no side effects causing the discontinuation of the training.

Conclusions

We demonstrated that a CT program effectively improved atrial function in patients with ICM in a dose-effect manner. This result can help with programming exercise training in this population.

Prognostic value of left atrial strain in aortic stenosis: A systematic review

PURPOSE

Aortic stenosis (AS) is a common valvular heart disease with high morbidity and mortality. Recently, the association between peak atrial longitudinal strain (PALS) and AS clinical outcomes has been identified. This systematic review evaluates the prognostic value of PALS for adverse events in AS.

METHODS

We performed a systematic literature review to identify clinical studies that evaluated Speckle-Tracking Echocardiography (STE)-derived PALS to predict adverse outcomes in patients with AS. We excluded studies that compared echocardiography to computed tomography and studies that focused on diseases other than AS.

RESULTS

We included 18 studies reporting on 2660 patients. Patients with symptomatic AS had decreased PALS when compared to patients with asymptomatic AS. Patients with AS who had adverse events had decreased PALS when compared to patients with AS with no events. Each unit increase of PALS was independently associated with decreased risk for the primary endpoint. PALS cut-off values were associated with increased risk for the primary endpoint.

CONCLUSION

This systematic review suggests PALS as an independent predictor for cardiovascular events in patients with AS and highlights the importance of evaluating LA mechanics for AS prognosis.

Sex-Related Differences of Left Atrial Strain in Patients With Hypertension Using Cardiac Magnetic Resonance Feature Tracking

PURPOSE

Previous studies demonstrated the impact of sex on left ventricular (LV) strain in patients with essential hypertension. However, little is known about the effect of sex on left atrial (LA) strain in patients with hypertension. This study aimed to explore the sex-related differences of LA strain by using cardiac magnetic resonance feature tracking in patients with hypertension and preserved LV ejection fraction.

MATERIALS AND METHODS

One hundred and fifty hypertensive patients (100 men and 50 women) and 105 age-matched and sex-matched normotensive controls (70 men and 35 women) were retrospectively enrolled and underwent cardiac magnetic resonance examination. LA strain parameters included LA reservoir strain (εs), conduit strain (εe), pump strain (εa), and their corresponding strain rate (SRs, SRe, and SRa).

RESULTS

Men had significantly higher LV mass index, lower εs and εe than women in both patients and controls (all P <0.05). LA strain and strain rate were significantly reduced in hypertensive patients compared with controls, both in men and women (all P <0.05). In men, hypertension and its interaction were associated with increased LV mass index and decreased εs and εe. In multivariable analysis, men, LV ejection fraction, and LA minimum volume index remained independent determinants of εs and εe in all hypertensive patients (all P <0.05).

CONCLUSION

LA strain was significantly impaired in hypertensive patients, and men had more impaired LA strain than women. These findings further emphasize the sex-related differences in the response of LA strain to hypertension in the early stage.

Normal values for left atrial strain, volume, and function derived from 3D echocardiography: the Copenhagen City Heart Study

AIMS

3D echocardiographic (3DE) assessment of the left atrium (LA) is a new modality of potential clinical value. Age- and sex-based normative values are needed to benchmark these parameters for clinical use.

METHODS AND RESULTS

Of 4466 participants in the 5th Copenhagen City Heart Study, a prospective longitudinal cohort study on the general population, 2082 participants underwent 3DE of the LA. Healthy participants were included to establish normative values for LA strain, volume, and function by 3DE. The effects of age and sex were also evaluated. After excluding participants with comorbidities, 979 healthy participants (median age 44 years, 39.6% males) remained. The median and limits of normality (2.5th and 97.5th percentiles) for functional and volumetric measures were as follows: LA reservoir strain (LASr) 30.8% (18.4-44.2%), LA conduit strain (LAScd) 19.1% (6.8-32.0%), LA contractile strain 11.7% (4.3-22.2%), total LA emptying fraction (LAEF) 61.4% (47.8-71.0%), passive LAEF 37.7% (17.4-53.9%), active LAEF 37.4% (22.2-52.5%), LA minimum volume index (LAVimin) 10.2 (5.9-18.5) mL/m2, and LA maximum volume index (LAVimax) 26.8 (16.5-40.1) mL/m2. All parameters changed significantly with increasing age (P value for all <0.001). Significant sex-specific differences were observed for all parameters except active LAEF and LAVimax. Sex significantly modified the association between age and LASr (P for interaction < 0.001), LAScd (P for interaction < 0.001), LAVimin (P for interaction = 0.037), and total LAEF (P for interaction = 0.034) such that these parameters deteriorated faster with age in females than males.

CONCLUSION

We present age- and sex-specific reference material including limits of normality for LA strain, volume, and function by 3DE.

Left atrial strain is associated with long-term mortality in acute coronary syndrome patients

To investigate the long-term prognostic value of the left atrial (LA) strain indices - peak atrial longitudinal strain (PALS), peak conduit strain (PCS), and peak atrial contractile strain (PACS) in acute coronary syndrome (ACS) patients in relation to all-cause mortality. This retrospective study included ACS patients treated with percutaneous coronary intervention (PCI) and examined with echocardiography. Exclusion criteria were non-sinus rhythm during echocardiography, missing images, and inadequate image quality for 2D speckle tracking analysis of the LA. The endpoint was all-cause death. Multivariable Cox regression which included relevant clinical and echocardiographic measures was utilized to assess the relationship between LA strain parameters and all-cause mortality. A total of 371 were included. Mean age was 64 years and 76% were male. Median time to echocardiography was 2 days following PCI. During a median follow-up of 5.7 years, 83 (22.4%) patients died. Following multivariable analysis, PALS (HR 1.04, 1.01-1.06, p = 0.002, per 1% decrease) and PCS (HR 1.05, 1.01-1.09, p = 0.006, per 1% decrease) remained significantly associated with all-cause mortality. PALS and PCS showed a linear relationship with the outcome whereas PACS was associated with the outcome in a non-linear fashion such that the risk of death increased when PACS < 18.22%. All LA strain parameters remained associated with worse survival rate when restricting analysis to patients with left atrial volume index < 34 ml/m2. Reduced LA function as assessed by PALS, PCS, and PACS were associated with an increased risk of long-term mortality in patients with ACS.

Inflammatory-mediated atrial cardiomyopathy diagnosed using multimodality imaging and successfully treated with prednisolone: a case report

Background

Atrial fibrillation is a common cardiac arrhythmia and often develops secondary to structural cardiac changes. Both the occurrence of atrial fibrillation and/or structural changes of the heart may lead to development of atrial cardiomyopathy and heart failure (HF). However, isolated atrial cardiomyopathy caused by focal atrial thickening is a rare condition, previously only described in case reports as a result of different aetiologies all linked to inflammation.

Case summary

A patient with inflammatory-mediated atrial cardiomyopathy causing atrial fibrillation and acute decompensated HF presented as isolated left atrial wall thickening on transoesophageal echocardiography. The diagnosis was confirmed using multimodality imaging with transthoracic and transoesophageal echocardiography, cardiac magnetic resonance imaging, positron emissions tomography/computer tomography scanning and intracardiac echocardiography-guided endomyocardial biopsy. Despite no specific histological aetiology, the observed atrial cardiomyopathy might be associated with type 1 diabetes mellitus. The patient in the present case was successfully treated with prednisolone.

Discussion

Diabetes mellitus is an important risk factor for developing atrial fibrillation and diabetic cardiomyopathy, due to reduced levels of anti-inflammatory and increased levels of proinflammatory cytokines causing cardiac inflammatory structural remodelling. The regression of the atrial thickening might be due to prednisolone's anti-inflammatory effects and thereby ability to suppress atrial remodelling and reduce the occurrence of atrial fibrillation. However, the effect of prednisolone might only affect the non-manifested inflammatory-mediated atrial remodelling. Due to the rare occurrence of isolated atrial cardiomyopathy a multiple imaging approach during the diagnostic process and follow-ups are essential to determine the aetiology and effect of the treatment.

Left atrial function of patients with atrial fibrillation undergoing thoracoscopic hybrid ablation

OBJECTIVES

Thoracoscopic hybrid ablation is an effective and safe rhythm control strategy for patients with complex forms of atrial fibrillation. Its effect on left atrial function has not yet been studied.

METHODS

In a retrospective single-centre analysis of patients undergoing thoracoscopic hybrid ablation, the left atrial emptying fraction was calculated using the biplane modified Simpson method in the apical 2- and 4-chamber views on transthoracic echocardiography. Left atrial strain (reservoir, conduction and contractility) was quantified using dedicated software.

RESULTS

Sixty-seven patients were included (mean age 64 years, long-standing persistent atrial fibrillation in 69%, median atrial fibrillation history duration 64 months). At baseline, left atrial function and contractility were poor. The reservoir and contractile strain improved postprocedure compared to baseline [15 (standard deviation (SD): 8) and 17 (SD: 6); P = 0.013; 3 (SD: 5) and 4 (SD: 4), P = 0.008], whereas the left atrial volume indexed to the body surface area was reduced [51 ml/m2 (SD: 14) and 47 ml/m2 (SD: 18), P = 0.0024]. In patients with preoperative (long-standing) persistent atrial fibrillation and in patients with rhythm restoration, improvements in the emptying fraction, (reservoir and contractile) strain and the left ventricular ejection fraction were observed, whereas the left atrial volume decreased (P < 0.05).

CONCLUSIONS

In this cohort of patients with severely diseased left atria, improvement in left atrial contractility and in the emptying fraction after thoracoscopic hybrid ablation for atrial fibrillation in patients with persistent atrial fibrillation is mainly due to rhythm restoration. Interestingly, the procedure itself also results in improved left atrial reservoir strain and reversed left atrial remodelling by reducing left atrial volume.

Left atrial strain in fetal echocardiography - could it be introduced to everyday clinical practice?

OBJECTIVES

Prenatal cardiology is a part of preventive cardiology based on fetal echocardiography and fetal interventional cardiology, which facilitates treatment of congenital heart defects (CHD) in pediatric patients and consequently in adults. Timely prenatal detection of CHD plays a pivotal role in facilitating the appropriate referral of pregnant women to facilities equipped to provide thorough perinatal care within the framework of a well-structured healthcare system. The aim of this paper is to highlight the role of left atrial strain (LAS) in prenatal evaluation of fetal heart and prediction of structural and functional disorders.

METHODS

We conducted a comprehensive literature review searching PubMed for articles published from inception up until August 2023, including the search terms "left atrial strain", "fetal echocardiography", and "prenatal cardiology" combined through Boolean operators. In addition, references lists of identified articles were further reviewed for inclusion.

RESULTS

Our review underscores the significance of LAS parameters in fetal echocardiography as a screening tool during specific gestational windows (starting from 11 to 14 weeks of gestation, followed by better visualization between 18 and 22 weeks of gestation). The left atrial strain technique and its parameters serve as valuable indicators, not only for identifying cardiac complications but also for predicting and guiding therapeutic interventions in cases of both cardiac and noncardiac pregnancy complications in fetuses. Evidence suggests establishment of second-trimester reference strain and strain rate values by speckle-tracking echocardiography in the healthy fetal cohort is essential for the evaluation of myocardial pathologies during pregnancy.

CONCLUSIONS

Finding of LAS of fetal heart is feasible and probably can have potential for clinical and prognostic implications.

Prognostic significance and clinical utility of left atrial reservoir strain in transcatheter aortic valve replacement

AIMS

Patients with diastolic dysfunction (DD) experience worse outcomes after transcatheter aortic valve replacement (TAVR). We investigated the prognostic value and clinical utility of left atrial reservoir strain (LARS) in patients undergoing TAVR for aortic stenosis (AS).

METHODS AND RESULTS

All consecutive patients undergoing TAVR between January 2018 and December 2018 were included if discharge echocardiography and follow-up were available. LARS was derived from 2D-speckle-tracking. Patients were grouped into three tertiles according to LARS. DD was analysed using the ASE/EACVI-algorithm. The primary outcome was a composite of all-cause death and readmission for worsening heart failure 12 months after TAVR. Overall, 606 patients were available [age 80 years, interquartile range (IQR) 77-84], including 53% women. Median LARS was 13.0% (IQR 8.4-18.3). Patients were classified by LARS tertiles [mildly impaired 21.4% (IQR 18.3-24.5), moderately impaired 13.0% (IQR 11.3-14.6), severely impaired 7.1% (IQR 5.4-8.4), P < 0.0001]. The primary outcome occurred more often in patients with impaired LARS (mildly impaired 7.4%, moderately impaired 13.4%, and severely impaired 25.7%, P < 0.0001). On adjusted multivariable Cox regression analysis, LARS tertiles [hazard ratio (HR) 0.62, 95% confidence interval (CI) 0.44-0.86, P = 0.005] and higher degree of tricuspid regurgitation (HR 1.82, 95% CI 1.23-2.98, P = 0.003) were the only significant predictors of the primary endpoint. Importantly, DD was unavailable in 56% of patients, but LARS assessment allowed for reliable prognostication regarding the primary endpoint in subgroups without DD assessment (HR 0.64, 95% CI 0.47-0.87, P = 0.003).

CONCLUSION

Impaired LARS is independently associated with worse outcomes in patients undergoing TAVR. LARS allows for risk stratification at discharge even in patients where DD cannot be assessed by conventional echocardiographic means.

Lower left atrial function in young individuals with type 1 diabetes mellitus compared to healthy controls: an echocardiographic study

In adulthood, individuals with type 1 diabetes mellitus may develop a condition of heart failure with preserved ejection fraction. However, subclinical changes to the heart in diabetes are likely to occur prior to the clinical presentation. This cross-sectional study aimed to compare left atrial function by echocardiography between 43 individuals with type 1 diabetes and 43 healthy controls, aged 10-30 years. All participants underwent echocardiography and 2D speckle tracking measurements for left atrial phase function parameters. Physical capacity was assessed by exercise test on a bicycle. Results showed that participants with type 1 diabetes had significantly lower left atrial function parameters than healthy controls (p < 0.05). There was a significant negative correlation between HbA1c means and reservoir and conduit strain (p < 0.05) and individuals with BMI < 30 showed a lower left atrial stiffness (p < 0.05). Individuals with type 1 diabetes and a higher physical capacity did not differ from their healthy peers. Results indicate that lower HbA1c levels, BMI < 30 and a higher physical capacity are favourable in terms of left atrial function in children and young adults with type 1 diabetes mellitus. Left atrial strain by echocardiography might become a new important tool in assessing heart function in T1DM.

Clinical and biochemical predictors of longitudinal changes in left atrial structure and function: A general population study

PURPOSE

There is a need for better understanding the factors that modulate left atrial (LA) dysfunction. Therefore, we determined associations of clinical and biochemical biomarkers with serial changes in echocardiographic indexes of LA function in the general population.

METHODS

We measured LA maximal and minimal volume indexes (LAVImax and LAVImin) by echocardiography and LA reservoir strain (LARS) by two-dimensional speckle-tracking in 627 participants (mean age 50.8 years, 51.2% women) at baseline and after 4.8 years.

RESULTS

During follow-up, LARS decreased significantly in men (-.90%, P = .033) but not in women (-.23%, P = .60). In stepwise regression analysis, stronger decrease in LARS over time was associated with male sex, a higher age, body mass index (BMI), mean arterial pressure (MAP) and serum insulin at baseline and with a greater increase in BMI and MAP over time (P ≤ .018). Similarly, an increased risk of developing or retaining abnormal LARS was observed in older participants, in subjects with a higher baseline BMI, MAP, heart rate (HR), troponin T and ΔMAP, and in those who used β-blockers at baseline. Both LAVImax and LAVImin increased significantly over time (P ≤ .0007). This increase was associated with a higher baseline age, pulse pressure and a lower HR at baseline and a greater increase in pulse pressure over time (P ≤ .029). Higher serum insulin and D-dimer were independently associated with a stronger increase in LAVImin (P ≤ .0034).

CONCLUSION

Subclinical worsening in LA dysfunction was associated with older age, hypertension, obesity, insulin resistance and troponin T levels. Cardiovascular risk management strategies may delay LA deterioration.

Left atrial pump strain predicts long-term survival after transcatheter aortic valve implantation

BACKGROUND

This study aims at investigating left atrial (LA) deformation by left atrial reservoir (LARS) and pump strain (LAPS) and its implications for long-term survival in patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve implantation (TAVI).

METHODS

Speckle tracking echocardiography was performed in 198 patients with severe AS undergoing TAVI. Association of strain parameters with cardiovascular mortality was determined.

RESULTS

Over a follow-up time of 5 years, 49 patients (24.7%) died. LAPS was more impaired in non-survivors than survivors (P = 0.010), whereas no difference was found for LARS (P = 0.114), LA ejection fraction (P = 0.241), and LA volume index (P = 0.292). Kaplan-Meier analyses yielded a reduced survival probability according to the optimal threshold for LAPS (P = 0.002). A more impaired LAPS was associated with increased mortality risk (HR 1.12 [95% CI 1.02-1.22]; P = 0.014) independent of LVEF, LAVI, age, and sex. Addition of LAPS improved multivariable echocardiographic (LVEF, LAVI) and clinical (age, sex) models with potential incremental value for mortality prediction (P = 0.013 and P = 0.031, respectively). In contrast, LARS and LAVI were not associated with mortality.

CONCLUSIONS

In patients undergoing aortic valve replacement for severe AS, LAPS was impaired in patients dying during long-term follow-up after TAVI, differentiated survivors from non-survivors, was independently associated with long-term mortality, and yielded potential incremental value for survival prediction after TAVI. LAPS seems useful for risk stratification in severe AS and timely valve replacement.

Left atrial strain, embolic stroke of undetermined source, and atrial fibrillation detection

BACKGROUND

Atrial cardiopathy is a proposed mechanism of embolic stroke of undetermined source (ESUS). Left atrial (LA) strain may identify early atrial cardiopathy prior to structural changes. We aim to study the associations between LA strain, ESUS, and atrial fibrillation (AF) detection in ESUS.

METHODS

The study population included patients with ESUS and noncardioembolic (NCE) stroke presenting to the Rhode Island Hospital Stroke Center between January 2016 and June 2017 who underwent transthoracic echocardiography. Speckle tracking echocardiography (STE) was used to measure the three phases of LA strain (reservoir, conduit, and contractile). Binary logistic regression analysis was performed to determine the associations between LA strain and stroke subtype (ESUS vs. NCE) as well as follow-up detection of AF in ESUS patients.

RESULTS

We identified 656 patients, 307 with ESUS and 349 with NCE. In binary logistic regression, the lowest tertiles of LA reservoir (adjusted OR 1.944, 95% CI 1.266-2.986, p = .002), contractile (aOR 1.568, 95% CI 1.035-2.374, p = .034), and conduit strain (aOR 2.288, 95% CI 1.448-3.613, p = .001) were more likely to be significantly associated with ESUS compared to NCE stroke. Among all ESUS patients, the lowest tertiles of LA reservoir strain (OR 2.534, 95% CI 1.029-6.236, p = .043), contractile strain (OR 2.828, 95% CI 1.158-6.903, p = .022), and conduit strain (OR 2.614, 95% CI 1.003-6.815, p = .049) were significantly associated with subsequent detection of AF.

CONCLUSION

Reduced LA strain is associated with ESUS occurrence and AF detection in ESUS patients. Therefore, quantification of LA strain in ESUS patients may improve risk stratification and guide secondary prevention strategies.

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

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

Impact of enzyme replacement therapy and migalastat on left atrial strain and cardiomyopathy in patients with Fabry disease

Aims

Cardiomyopathy in Fabry disease (FD) is a major determinant of morbidity and mortality. This study investigates the effects of FD-specific treatment using enzyme replacement therapy (ERT) and chaperone therapy on left atrial (LA) function using two-dimensional speckle tracking echocardiography (2DSTE).

Methods and results

In this prospective observational single-center study, 20 FD patients [10 (50%) females] treated with migalastat, 48 FD patients [24 (50%) females] treated with ERT (agalsidase-alfa and agalsidase-beta), and 30 untreated FD patients (all females) as controls were analyzed. The mean follow-up time ranged from 26 to 81 months. 2DSTE was performed for left ventricle strain, right ventricle strain, and LA strain (LAS). FD-specific treated patients presented with increased left ventricular mass index (LVMi) and higher frequency of left ventricular hypertrophy at baseline, whereas untreated control patients showed normal baseline values. FD-specific treated (including migalastat and ERT) patients showed stabilization of LAS over time (p > 0.05). LVMi was also stable in treated FD patients during observation (p > 0.05).

Conclusion

In patients with FD, treated with either ERT or chaperone therapy, LAS values measured by echocardiographic speckle tracking were stable over time, pointing toward disease stabilization.

Left atrial phasic function: physiology, clinical assessment and prognostic value

Left atrial (LA) phasic function provides significant insights into the pathophysiology of cardiovascular disease. LA function is described in three phases: reservoir (atrial filling, during systole), conduit (passive emptying, during early diastole) and contractile (active emptying, during late diastole). LA phasic function can be evaluated by different imaging modalities, and a variety of techniques including volumetric analysis, deformation (strain) and Doppler methods. LA phasic function (particularly LA reservoir strain) is more sensitive and provides earlier detection of LA dysfunction than alterations in LA volume. LA function parameters have also demonstrated significant diagnostic and prognostic value, particularly in heart failure, atrial fibrillation and stroke. However, there remain barriers to implementation of phasic function parameters in clinical practice and guidelines. This review outlines the physiology of LA phasic function, methods of assessment, and its diagnostic and prognostic utility in varying pathologies.

Associations of brachial-ankle pulse wave velocity with left atrial stiffness and left atrial phasic function in inpatients with hypertension

Hypertension induces left atrial (LA) and left ventricular (LV) dysfunction, and an increase in arterial stiffness. This study aimed to investigate the associations of brachial-ankle pulse wave velocity (baPWV) with LA stiffness and LA phasic function in hypertension. A total of 305 hypertensive inpatients enrolled and were divided into two groups based on baPWV [Group I, baPWV ≤ 1515 (cm/s), n = 153; Group II, baPWV > 1515 (cm/s), n = 152]. Two-dimensional speckle tracking echocardiography (2D-STE) based LA phasic strains (LAS-S, LAS-E, LAS-A) and LV global longitudinal strain (LVGLS) were evaluated. LA stiffness index (LASI) was defined as the ratio of E/e' to LAS-S. Multivariate linear regression modeling was used to analyze the associations of baPWV with LASI and LA phasic function in all patients as well as age-specific and sex-specific subgroups. LASI was significantly higher in Group II [0.35(0.26, 0.52)] compared with Group I [0.26(0.20, 0.36)] (P < 0.001). After adjusting cardiovascular risk factors, medication, and LV structural and functional parameters (LVEF, LVMI, E/A ratio, and LVGLS), baPWV remained significantly correlated with LASI (P < 0.05). We also evaluated the predictive value of baPWV for LASI, the area under the curve (AUC) was 0.663 (95% CI: 0.607-0.716, P < 0.001). In conclusion, BaPWV was independently associated with LA stiffness in hypertensive inpatients. BaPWV also exhibited a certain predictive value for LA stiffness in these inpatients. Measuring arterial stiffness can provide clinicians clues for early cardiac target organ damage (TOD) in addition to vascular TOD.

Compressed sensing cine imaging with higher temporal resolution for analysis of left atrial strain and strain rate by cardiac magnetic resonance feature tracking

PURPOSE

Cardiac magnetic resonance (CMR) feature tracking (FT) is more widely used in the measurement of left atrial (LA) strain and strain rate (SR). However, in recent years, researchers have attempted to improve the low temporal resolution of CMR-FT to better capture the subtle deformations of the myocardium. The technique of compressed sensing (CS) has been applied clinically, reducing scan time while increasing temporal resolution. The purpose of this study was to explore the effect of the increased temporal resolution of CS cine sequences on the analysis of LA longitudinal strain and SR.

MATERIALS AND METHODS

Twenty-nine healthy subjects were included in the study. They underwent CMR with a reference steady-state free precession cine sequence of conventional temporal resolution (standard SSFP sequence), a cine sequence of higher temporal resolution (HT sequence), and an HT cine sequence with CS (CS HT sequence) (temporal resolution: 22.1-44.3/24.9-47.1 ms, 11.1-19.4 ms, and 8.3-19.4 ms, respectively). The standard SSFP sequence, HT sequence, and CS HT sequence were acquired in all subjects during the same scanning session. LA longitudinal strain and SR, reflecting LA reservoir, conduit, and contraction booster-pump function, were measured by CMR-FT and compared among the three sequences.

RESULTS

The measurements of LASR reservoir, conduit, and booster-pump were significantly higher on the HT and CS HT sequences than on the standard SSFP sequence. The standard SSFP sequence was correlated significantly with the HT and CS HT sequences in terms of LA strain and SR analysis, respectively. The LA strain and SR measurements also showed excellent agreement between the HT and CS HT sequences.

CONCLUSION

Higher temporal resolution led to significantly higher measured LASR values in CMR-FT. Furthermore, the addition of CS reduced scan time and did not affect LA longitudinal strain or SR analysis.

Phenotyping heart failure by echocardiography: imaging of ventricular function and haemodynamics at rest and exercise

Traditionally, congestive heart failure (HF) was phenotyped by echocardiography or other imaging techniques according to left ventricular (LV) ejection fraction (LVEF). The more recent echocardiographic modality speckle tracking strain is complementary to LVEF, as it is more sensitive to diagnose mild systolic dysfunction. Furthermore, when LV systolic dysfunction is associated with a small, hypertrophic ventricle, EF is often normal or supernormal, whereas LV global longitudinal strain can reveal reduced contractility. In addition, segmental strain patterns may be used to identify specific cardiomyopathies, which in some cases can be treated with patient-specific medicine. In HF with preserved EF (HFpEF), a diagnostic hallmark is elevated LV filling pressure, which can be diagnosed with good accuracy by applying a set of echocardiographic parameters. Patients with HFpEF often have normal filling pressure at rest, and a non-invasive or invasive diastolic stress test may be used to identify abnormal elevation of filling pressure during exercise. The novel parameter LV work index, which incorporates afterload, is a promising tool for quantification of LV contractile function and efficiency. Another novel modality is shear wave imaging for diagnosing stiff ventricles, but clinical utility remains to be determined. In conclusion, echocardiographic imaging of cardiac function should include LV strain as a supplementary method to LVEF. Echocardiographic parameters can identify elevated LV filling pressure with good accuracy and may be applied in the diagnostic workup of patients suspected of HFpEF.

Multimodality Imaging in Patients with Hypertrophic Cardiomyopathy and Atrial Fibrillation

Ventricular hypertrophy is associated with diastolic dysfunction, resulting in increased left atrial (LA) pressure, enlargement, fibrosis, and decreased LA function. Hypertrophic cardiomyopathy (HCM) is characterized by myocyte disarray, myocardial fibrosis, and hypertrophy. Notably, a thickened and noncompliant LV results in the impairment of diastolic function. These conditions promote LA remodeling and enlargement, which contribute to developing and maintaining atrial fibrillation (AF). AF is an atrial arrhythmia that occurs frequently in HCM, and evaluating the morphology and physiology of the atrium and ventricle is important for treatment and prognosis determination in HCM patients with AF. In addition, it provides a clue that can predict the possibility of new AF, even in patients not previously diagnosed with AF. Cardiac magnetic resonance (CMR), which can overcome the limitations of transthoracic echocardiography (TTE), has been widely used traditionally and even enables tissue characterization; moreover, it has emerged as an essential imaging modality for patients with HCM. Here, we review the role of multimodal imaging in patients with HCM and AF.

Acute Changes on Left Atrial Function during Incremental Exercise in Patients with Heart Failure with Mildly Reduced Ejection Fraction: A Case-Control Study

BACKGROUND

the aim of this study was to assess acute changes in left atrial (LA) function during incremental aerobic exercise in patients with heart failure with mildly reduced ejection fraction (HFmrEF) in comparison to healthy subjects (HS).

METHODS

twenty patients with established HFmrEF were compared with 10 HS, age-matched controls. All subjects performed a stepwise exercise test on a cycle ergometer. Echocardiography was performed at baseline, during submaximal effort, at peak of exercise, and after 5 min of recovery.

RESULTS

HS obtained a higher value of METs at peak exercise than HFmrEF (7.4 vs. 5.6; between group p = 0.002). Heart rate and systolic blood pressure presented a greater increase in the HS group than in HFmrEF (between groups p = 0.006 and 0.003, respectively). In the HFmrEF group, peak atrial longitudinal strain (PALS) and conduit strain were both increased at submaximal exercise (p < 0.05 for both versus baseline) and remained constant at peak exercise. Peak atrial contraction strain (PACS) did not show significant changes during the exercise. In the HS group, PALS and PACS increased significantly at submaximal level (p < 0.05 for both versus baseline), but PALS returned near baseline values at peak exercise; conduit strain decreased progressively during the exercise in HS. Stroke volume (SV) increased in both groups at submaximal exercise; at peak exercise, SV remained constant in the HFmrEF, while it decreased in controls (between groups p = 0.002).

CONCLUSIONS

patients with HFmrEF show a proper increase in LA reservoir function during incremental aerobic exercise that contributes to maintain SV throughout the physical effort.

Age- and sex-based normal reference ranges of the cardiac time intervals: the Copenhagen City Heart Study

BACKGROUND

Color tissue Doppler imaging (TDI) M-mode can be used to measure the cardiac time intervals including the isovolumic contraction time (IVCT), the left ventricular ejection time (LVET), the isovolumic relaxation time (IVRT), and the combination of all the cardiac time intervals in the myocardial performance index (MPI) defined as [(IVCT + IVRT)/LVET]. The aim of this study was to establish normal age- and sex-based reference ranges for the cardiac time intervals.

METHODS AND RESULTS

A total of 1969 participants free of cardiovascular diseases and risk factors from the general population with limited age range underwent an echocardiographic examination including TDI. The median age was 46 years (25th-75th percentile: 33-58 years), and 61.5% were females. In the entire study population, the IVCT was observed to be 40 ± 10 ms [95% prediction interval (PI) 20-59 ms], the LVET 292 ± 23 ms (95% PI 248-336 ms), the IVRT 96 ± 19 ms (95% PI 59-134 ms) and MPI 0.47 ± 0.09 (95% PI 0.29-0.65). All the cardiac time intervals differed significantly between females and males. With increasing age, the IVCT increased in females, but not in males. The LVET did not change with age in both sexes, while the IVRT increased in both sexes with increasing age. Furthermore, we developed regression equations relating the heart rate to the cardiac time intervals and age- and sex-based normal reference ranges corrected for heart rate.

CONCLUSION

In this study, we established normal age- and sex-based reference ranges for the cardiac time intervals. These normal reference ranges differed significantly with sex.

Atrial Cardiomyopathy in Valvular Heart Disease: From Molecular Biology to Clinical Perspectives

This review discusses the evolving topic of atrial cardiomyopathy concerning valvular heart disease. The pathogenesis of atrial cardiomyopathy involves multiple factors, such as valvular disease leading to atrial structural and functional remodeling due to pressure and volume overload. Atrial enlargement and dysfunction can trigger atrial tachyarrhythmia. The complex interaction between valvular disease and atrial cardiomyopathy creates a vicious cycle of aggravating atrial enlargement, dysfunction, and valvular disease severity. Furthermore, atrial remodeling and arrhythmia can predispose to atrial thrombus formation and stroke. The underlying pathomechanism of atrial myopathy involves molecular, cellular, and subcellular alterations resulting in chronic inflammation, atrial fibrosis, and electrophysiological changes. Atrial dysfunction has emerged as an essential determinant of outcomes in valvular disease and heart failure. Despite its predictive value, the detection of atrial fibrosis and dysfunction is challenging and is not included in the clinical routine. Transthoracic echocardiography and cardiac magnetic resonance imaging are the main diagnostic tools for atrial cardiomyopathy. Recently published data have revealed that both left atrial volumes and functional parameters are independent predictors of cardiovascular events in valvular disease. The integration of atrial function assessment in clinical practice might help in early cardiovascular risk estimation, promoting early therapeutic intervention in valvular disease.

The Improvement of Left Atrial Function after Twelve Weeks of Supervised Concurrent Training in Patients with Heart Failure with Mid-Range Ejection Fraction: A Pilot Study

Left atrial dysfunction is associated with exercise intolerance and poor prognosis in heart failure (HF). The effects of exercise training on atrial function in patients with HF with mid-range ejection fraction (HFmrEF) are unknown. The purpose of the present study was to assess the effects of a supervised concurrent training (SCT) program, lasting 12 weeks, on left atrial function of patients with HFmrEF. The study included 70 stable patients, who were randomly assigned into two groups: SCT with (three sessions/week) or a control (CON) group directed to follow contemporary exercise preventive guidelines at home. Before starting the training program and at 12 weeks, all patients performed an ergometric test, a 6 min walk test, and echocardiography. Between-group comparisons were made by analysis of variance (ANOVA). At 12 weeks, the duration of the ergometric test and distance walked at 6 min walk test presented a significant greater increase in SCT compared to the control (between-group p 0.0001 and p 0.004 respectively). Peak atrial longitudinal strain and conduit strain presented an increase of 29% and 34%, respectively, in the SCT, and were unchanged in CON (between-group p 0.008 and p 0.001, respectively). Peak atrial contraction strain increased by 21% in SCT, with no changes in CON (between-group p 0.002). Left ventricular global longitudinal strain increased significantly in SCT compared to control (between-groups p 0.03). In conclusions, SCT improved left atrial and left ventricular function in HFmrEF. Further studies are needed in order to verify whether these favourable effects of SCT on LA function are sustained and whether they will translate into clinical benefits for patients with HFmrEF.

Value of Left Atrial Strain in Predicting Recurrence after Atrial Fibrillation Ablation

This study tested the relationship between left atrial (LA) function parameters and the results of pulmonary vein isolation (PVI) in patients with atrial fibrillation (AF). Consecutive patients undergoing PVI for the first time between 2019 and 2021 were included. Patients underwent radiofrequency ablation using contact force catheters and an electroanatomical system. Follow-up consisted of ambulatory visits/televisits and 7-day Holter monitoring (at 6 and 12 months after ablation). On the day of ablation, all patients underwent transesophageal and transthoracic echocardiography with LA strain analysis. The primary endpoint was atrial tachyarrhythmia recurrence during the follow-up period. Of 221 patients, 22 did not meet the echocardiographic quality criteria, leaving 199 patients. The median follow-up period was 12 months, and 12 patients were lost to follow-up. Recurrences were observed in 67 patients (35.8%) after a mean of 1.06 procedures per patient. The patients were divided into a sinus rhythm (SR, n = 109) group and an AF (n = 90) group based on their cardiac rhythm at the time of echocardiography. In the SR group, univariable analysis showed that LA reservoir strain, LA appendage emptying velocity (LAAV), and LA volume index predicted AF recurrence, with only LAAV being significant in the multivariable analysis. In AF patients, univariable analysis revealed no LA strain parameters predicting AF recurrence.

Left atrial appendage strain predicts subclinical atrial fibrillation in embolic strokes of undetermined source

Aims

Left atrial (LA) strain is promising in prediction of clinical atrial fibrillation (AF) in stroke patients. However, prediction of subclinical AF is critical in patients with embolic strokes of undetermined source (ESUS). The aim of this prospective study was to investigate novel LA and left atrial appendage (LAA) strain markers in prediction of subclinical AF in ESUS patients.

Methods and results

A total of 185 patients with ESUS, mean age 68 ± 13years, 33% female, without diagnosed AF, were included. LAA and LA function by conventional echocardiographic parameters and reservoir strain (Sr), conduit strain (Scd), contraction strain (Sct), and mechanical dispersion (MD) of Sr were assessed with transoesophageal and transthoracic echocardiography. Subclinical AF was detected by insertable cardiac monitors during follow-up. LAA strain was impaired in 60 (32%) patients with subclinical AF compared to those with sinus rhythm: LAA-Sr, 19.2 ± 4.5% vs. 25.6 ± 6.5% (P < 0.001); LAA-Scd, -11.0 ± 3.1% vs. -14.4 ± 4.5% (P < 0.001); and LAA-Sct, -7.9 ± 4.0% vs. -11.2 ± 4% (P < 0.001), respectively, while LAA-MD was increased, 34 ± 24 ms vs. 26 ± 20 ms (P = 0.02). However, there was no significant difference in phasic LA strain or LA-MD. By ROC analyses, LAA-Sr was highly significant in prediction of subclinical AF and showed the best AUC of 0.80 (95% CI 0.73-0.87) with a sensitivity of 80% and a specificity of 73% (P < 0.001). LAA-Sr and LAA-MD were both independent and incremental markers of subclinical AF in ESUS patients.

Conclusion

LAA function by strain and mechanical dispersion predicted subclinical AF in ESUS patients. These novel echocardiographic markers may improve risk stratification in ESUS patients.

Atrial Dysfunction in Significant Atrial Functional Mitral Regurgitation: Phenotypes and Prognostic Implications

BACKGROUND

Atrial functional mitral regurgitation (AFMR) is associated with increased morbidity and mortality. Left atrial (LA) size and function in AFMR are poorly characterized. We aimed to assess LA function by reservoir strain (LASr) and estimated reservoir work (LAWr) and their impact on outcome in AFMR.

METHODS

Consecutive patients at our institution between 2001 and 2019 and with significant (moderate or greater) AFMR were examined. LAWr was estimated as LASr×LA reservoir volume, and patients were grouped by median LASr and LAWr. Outcomes were all-cause death or heart failure hospitalizations.

RESULTS

Five hundred fifteen AFMR patients were followed up for 5 (1-17) years. Patients had previously documented atrial fibrillation (AF; 37%), heart failure with preserved ejection fraction (HFpEF) without AF (24%), or both (HFpEF+AF, 39%). LA volume was largest in AF, while LA function parameters were most impaired in the combined HFpEF+AF group. During follow-up, patients with low LASr or LAWr had higher risk of death (P<0.001) and heart failure hospitalization (P<0.05). In Cox regression analyses, low LASr and LAWr, but not LA volume or left ventricular function, were associated with a higher risk of death (LASr: hazard ratio, 2.3 [95% CI, 1.6-3.5]; LAWr: hazard ratio, 3.4 [95% CI, 2.4-4.9]; both P<0.001) after adjustment for clinical and echocardiographic confounders. Low LASr and LAWr were strongest associated with death in HFpEF and HFpEF+AF.

CONCLUSIONS

LA reservoir function but not LA size is a robust predictor of outcome in significant AFMR. This provides mechanistic insights into the interplay of functional versus geometric LA changes in AFMR.

Left atrial strain parameters derived by echocardiography are impaired in patients with acute myocarditis and preserved systolic left ventricular function

PURPOSE

Data derived by cardiac magnetic resonance (CMR) feature tracking suggest that not only left ventricular but also left atrial function is impaired in patients with acute myocarditis. Therefore, we investigated the diagnostic value of speckle tracking echocardiography of the left ventricle and left atrium in patients with acute myocarditis and normal left ventricular ejection fraction (LVEF).

METHODS AND RESULTS

30 patients with acute myocarditis confirmed by CMR according to the Lake Louise criteria and 20 healthy controls were analyzed including global longitudinal strain (GLS) and left atrial (LA) strain parameters. Although preserved LVEF was present in both groups, GLS was significantly lower in patients with acute myocarditis (GLS - 19.1 ± 1.8% vs. GLS - 22.1 ± 1.7%, p < 0.001). Further diastolic dysfunction measured by E/e' mean was significantly deteriorated in the myocarditis group compared to the control group (E/e' mean 6.4 ± 1.6 vs. 5.5 ± 1.0, p = 0.038). LA reservoir function (47.6 ± 10.4% vs. 55.5 ± 10.8%, p = 0.013) and LA conduit function (-33.0 ± 9.6% vs. -39.4 ± 9.5%, p = 0.024) were significantly reduced in patients with acute myocarditis compared to healthy controls. Also left atrial stiffness index (0.15 ± 0.05 vs. 0.10 ± 0.03, p = 0.003) as well as left atrial filling index (1.67 ± 0.47 vs. 1.29 ± 0.34, p = 0.004) were deteriorated in patients with myocarditis compared to the control group.

CONCLUSION

In patients with acute myocarditis and preserved LVEF not only GLS but also LA reservoir function, LA conduit function and left atrial stiffness index as well as left atrial filling index were impaired compared to healthy controls indicating ventricular diastolic dysfunction and elevated LV filling pressures.

Diastolic Function and Left Atrial Strain in Young Patients with History of Aortic Coarctation Repair

Aortic coarctation (AoCo) leads to long-term sequelae that may impair heart function. Data regarding new echocardiographic function parameters such as atrial strain, in affected patients, are scarce. This study aims to describe these parameters in AoCo patients and define their association with severity measures. 53 AoCo patients and 31 healthy controls, aged 12-40 years, were evaluated. Effectively corrected AoCo (cAoCo) was defined as aortic trans-isthmic corrected Doppler gradient (Dgrad) ≤ 20 mmHg (n = 36), and recoarctation (rAoCo) as Dgrad > 20 mmHg (n = 17). Dependent variables were: E/E'; atrial reservoir strain (Ares); and atrial conduit strain (Acd). T-tests/Mann-Whitney U tests were used to compare these among groups. Multivariable regression was used to test correlation with systolic blood pressure (SBP), indexed LV mass (ILVM), Dgrad, and the ratio between the narrowest diameter of aortic arch and aorta at diaphragm level (Aoratio). In cAoCo and rAoCo patients, E/E' was higher (p < 0.001), Ares, and Acd were lower (p < 0.001 for both) comparing with controls. Acd was higher in cAoCo than rAoCo (p = 0.045). Higher Ares was associated with higher Aoratio (p = 0.002), and lower Acd with higher Dgrad (0.014). EF and GLS were not different among groups. Young patients with effectively corrected aortic coarctation have persistent changes in diastolic function parameters (E/E' and atrial strain), and these are affected by anatomical sequelae. These patients' physiology is closer to patients with recoarctation, than to healthy individuals. This provides rationale for a stronger prevention, and treatment, of arterial dysfunction and high left ventricular afterload in these patients.

Left atrial strain evaluation to assess left ventricle diastolic dysfunction and heart failure with preserved ejection fraction: a guide to clinical practice : Left atrial strain and diastolic function

Although frequently unrecognized, left atrium (LA) function plays a key role in global cardiac performance as it modulates left ventricle (LV) filling through three main functions: the LA reservoir, conduit and booster pump. Given the interdependence between the LA and the LV, it is known that LA dimension and/or LA function can be used as a surrogate for LV diastolic function.Recently, LA deformation analysis using 2-dimensional (2D) speckle tracking echocardiography (STE) strain emerged as a promising non-invasive technique that can help to estimate LV filling pressures (LVFP) and diagnose heart failure with preserved ejection fraction (HFpEF), as recently proposed in the recent 2022 European Association of Cardiovascular Imaging (EACVI) consensus which included LA reservoir strain as an additive parameter to estimate LVFP.This article aims to review the latest evidence regarding the role of LA strain in the assessment and management of LV diastolic dysfunction (LVDD) and HFpEF, providing a clinical guide with tips and tricks to use LA strain as a new technique to help to estimate LVFP.

Left atrial strain assessment using cardiac computed tomography in patients with hypertrophic cardiomyopathy

PURPOSE

To evaluate left atrial (LA) function in patients with hypertrophic cardiomyopathy (HCM) by LA strain assessment using cardiac computed tomography (CT-derived LA strain).

MATERIALS AND METHODS

This was a retrospective study of 34 patients with HCM and 31 non-HCM patients who underwent cardiac computed tomography (CT) using retrospective electrocardiogram-gated mode. CT images were reconstructed every 5% (0-95%) of the RR intervals. CT-derived LA strain (reservoir [LASr], conduit [LASc], and booster pump strain [LASp]) were semi-automatically analyzed using a dedicated workstation. We also measured the left atrial volume index (LAVI) and left ventricular longitudinal strain (LVLS) for the left atrial and ventricular functional parameters to assess the relationship with CT-derived LA strain.

RESULTS

CT-derived LA strain significantly correlated with LAVI: r = - 0.69, p < 0.001 for LASr; r = - 0.70, p < 0.001 for LASp; and r = - 0.35, p = 0.004 for LASc. CT-derived LA strain also significantly correlated with LVLS: r = - 0.62, p < 0.001 for LASr; r = - 0.67, p < 0.001 for LASc; and r = - 0.42, p = 0.013 for LASp. CT-derived LA strain in patients with HCM was significantly lower than that in non-HCM patients: LASr (20.8 ± 7.6 vs. 31.7 ± 6.1%, p < 0.001); LASc (7.9 ± 3.4 vs. 14.2 ± 5.3%, p < 0.001); and LASp (12.8 ± 5.7 vs. 17.6 ± 4.3%, p < 0.001). Additionally, CT-derived LA strain showed high reproducibility; inter-observer correlation coefficients were 0.94, 0.90, and 0.89 for LASr, LASc, and LASp, respectively.

CONCLUSION

CT-derived LA strain is feasible for quantitative assessment of left atrial function in patients with HCM.