Strain echocardiographic assessment of left atrial function predicts recurrence of atrial fibrillation

Mechanism and Impact of Left Atrial Dyssynchrony on Long-Term Clinical Outcome During Cardiac Resynchronization Therapy

BACKGROUND

Left bundle branch block (LBBB) causes left atrial (LA) dyssynchrony. It is unknown if LA dyssynchrony impacts long-term prognosis.

OBJECTIVES

The purpose of this study was to determine mechanisms of LA dyssynchrony in LBBB and if LA dyssynchrony impacts long-term prognosis.

METHODS

In a prospective multicenter study of 168 heart failure patients with LBBB, echocardiographic strain imaging was done before and after 6 months with cardiac resynchronization therapy (CRT). Outcome was assessed after 6 years. Dyssynchrony was measured relative to septum as delay in left ventricular (LV) lateral wall shortening and LA lateral wall stretch. Response to CRT was defined as at least 15% reduction in LV end-systolic volume.

RESULTS

Before CRT, there was marked LA dyssynchrony of 105 ± 76 ms, which decreased to 37 ± 68 ms in CRT-responders (P < 0.001), whereas nonresponders showed only a modest reduction in LA dyssynchrony (P < 0.05). There was strong association between LA and LV dyssynchrony (r = 0.70), consistent with direct LV-LA mechanical interaction. CRT caused modest increase in LA reservoir strain (P < 0.01) and marked increase of LV filling time (P < 0.001) in responders. Mortality after 6 years was 21% (35 deaths). LA dyssynchrony did not independently predict mortality. However, the combination of preserved LA reservoir strain (≥18%) and resolved LA dyssynchrony (≤53 ms) after 6 months with CRT was associated with excellent long term-prognosis: HR: 0.11 (95% CI: 0.03-0.42) vs preserved reservoir strain and persistent LA dyssynchrony.

CONCLUSIONS

LA dyssynchrony in LBBB was attributed to direct LV-LA mechanical interactions. CRT improved diastolic function by increasing LV filling time. Patients with preserved LA reservoir strain and resolution of LA dyssynchrony by CRT had excellent long-term prognosis. (Contractile Reserve in Dyssynchrony: A Novel Principle to Identify Candidates for Cardiac Resynchronization Therapy [CRID-CRT]; NCT02525185).

Clinical, Electrocardiographic and Echocardiographic Predictors of Atrial Fibrillation Recurrence After Pulmonary Vein Isolation

Atrial fibrillation (AF) is a supraventricular arrhythmia and the most common heart rhythm disorder in the adult population worldwide with an estimated prevalence of 2% to 4% of the population. Cases of AF have shown an increasing trend in recent decades, while its frequency is expected to rise even more. Given the significant impact on patients' quality of life, as well as its major complications, including thromboembolic events, effective rhythm control strategies other than antiarrhythmic medication have emerged, with catheter ablation (CA) being the cornerstone of these. In recent years, CA has been upgraded to a first-line treatment for selected patients. However, complications do exist and arrhythmia-free survival is not always guaranteed. The need to better identify patients more suitable for this specific therapeutic measure is crucial in improving outcomes and preventing arrhythmia recurrences. This review aims to present currently identified predictors of AF recurrence after catheter ablation based on clinical characteristics and electrocardiographic and echocardiographic parameters, in an era of increasing interventional rhythm control approaches for the management of atrial fibrillation.

Left Atrial Reservoir Strain and Recurrence of Atrial Fibrillation Following De-Novo Pulmonary Vein Isolation - Results of the ASTRA-AF Pilot Study

BACKGROUND

Achieving early rhythm control and maintaining sinus rhythm are associated with improved outcomes in patients with atrial fibrillation (AF). Pulmonary vein isolation (PVI) is a validated alternative to medical rhythm control. This study determined associations between left atrial strain reservoir (LASR) and AF recurrence after PVI.

METHODS AND RESULTS

In all, 132 patients (88 with paroxysmal AF [PAF], 44 with persisting AF [PersAF]) who presented in sinus rhythm for de novo PVI of AF between December 2017 and January 2019 were included in the study. All patients underwent preprocedural echocardiography. After 12 months, all patients underwent 24-h Holter electrocardiogram monitoring to screen for AF recurrence. Kaplan-Meier curve analysis revealed an association between decreasing LASRand increased AF recurrence, with a cut-off at 31.4%. In univariable Cox regression analysis, LASRdemonstrated an association with AF recurrence, with hazard ratios (HR) of 0.83 (95% confidence interval [CI] 073-0.93; P=0.001) per 5% increase in univariable models and 0.83 (95% CI 073-0.95; P=0.005) in multivariable analysis. When clinical variables with age, sex and type of AF (PAF/PersAF) were included in the multivariable analysis, LASRremained relevant in a model with age (HR 0.86; 95% CI 073-1.00; P=0.046).

CONCLUSIONS

In patients undergoing de novo PVI for AF, LASRcould be of use in risk stratification regarding AF recurrence.

Association of atrial mechanical dispersion with atrial fibrillation recurrence following catheter ablation: results of the ASTRA-AF pilot study

AIMS

For patients with symptomatic drug-refractory atrial fibrillation (AF), catheter ablation to achieve rhythm control is an important therapeutic option. The atrial mechanical dispersion measured as standard deviation of the time to peak strain (SD-TPS) is associated with the risk of AF recurrence following catheter ablation.

METHODS

The study cohort prospectively enrolled n = 132 consecutive patients with paroxysmal (n = 88) or persistent AF (n = 44) presenting for de novo pulmonary vein isolation (PVI) and followed for 1 year. We related left atrial (LA) volume, LA ejection fraction, SD-TPS, and global longitudinal strain of the left ventricle and clinical variables (sex, age, and type of AF) to AF recurrence.

RESULTS

Kaplan-Meier curves showed higher AF recurrence rate with an increase of SD-TPS with the calculated cut-off of 38.6 ms. Uni- and multivariable Cox regression analysis could show that SD-TPS had the highest relevance regarding AF recurrence with a HR of 1.05 (95% CI, 1.01; 1.09, p = 0.01) and HR of 1.05 (95% CI, 1.01; 1.09, p = 0.02) per 10 ms increase. In the additional analyses for the model including the clinical variables age, sex, and type of AF with paroxysmal or persisting AF, SD-TPS did only show a trend and after adjusting for covariates, SD-TPS showed a HR of 1.04 (95% CI, 0.99; 1.09, p = 0.09) per 10 ms increase.

CONCLUSION

Atrial mechanical dispersion was associated with recurrent AF.

Left atrial strain measured by three-dimensional echocardiography predicts atrial fibrillation in the general population

BACKGROUND

Left atrial (LA) strain by three-dimensional echocardiography (3DE), has been proposed as a more accurate measure of LA function, providing incremental prognostic benefits over traditional two-dimensional approaches.

OBJECTIVES

Our aim was to evaluate the prognostic value of LA strain by 3DE in predicting incident atrial fibrillation (AF) in the general population.

METHODS

The study included 4466 participants from a prospective longitudinal cohort study in the general population, among these 3DE LA strain was analysed in 1935 participants. The endpoint was incident AF. Adjustments were made for the CHARGE-AF clinical risk score.

RESULTS

Mean age was 54 ± 17 years, 43 % were male. During a median follow-up time of 4.8 years (interquartile range 4.3-5.5 years) 59 participants (3.0 %) developed AF. In univariable analysis, all three parameters were associated with incident AF (p value for all <0.01). After multivariable adjustments, only LA reservoir strain (LASr) and LA contractile strain (LASct) were associated with incident AF (LASr: HR 1.12 (1.07-1.17), p < 0.001, per 1 % decrease; LASct: HR 1.16 (1.09-1.24), p < 0.001, per 1 % decrease), whereas LA conduit strain (LAScd) was not (HR 1.04 (0.98-1.10), p = 0.17, per 1 % decrease). Both LASr (continuous net reclassification index 0.37 ± 0.14; p = 0.003) and LASct (continuous net reclassification index 0.41 ± 0.14; p = 0.002) provided incremental prognostic information beyond the CHARGE-AF risk score.

CONCLUSION

LASr and LASct measured by 3DE are independently associated with incident AF and provided incremental prognostic information beyond existing risk scores.

Incidence, Correlates, and Prognostic Implications of New-Onset Atrial Fibrillation in Adults With Repaired Coarctation of Aorta

Background

There are limited data about the incidence and outcomes of atrial fibrillation (AF) in adults with coarctation of aorta (COA). The purpose of this study was to determine the incidence, correlates, and prognostic implications of new-onset AF in adults with repaired COA.

Methods

A retrospective cohort study of adults with repaired COA without a prior history of atrial arrhythmias was performed. We reviewed rhythm data (electrocardiogram, Holter, and rhythm strip) obtained from baseline to the last clinical encounter. The correlates of AF and the relationship between AF and cardiovascular adverse events (heart failure hospitalization and/or all-cause mortality) were assessed using Cox regression.

Results

Of 782 patients (aged 32 [interquartile range: 21-43] years; 462 [59%] men), 42 (5.4%) developed new-onset AF. The incidence of new-onset AF was 9 per 1000 patient-years (0.9% per year), and the median age at onset of AF was 36 (interquartile range: 24-49) years. The correlates of new-onset AF were older age, hypertension, left atrial dysfunction, and left ventricular hypertrophy. Of 782 patients, 92 (12%) had cardiovascular adverse events. On multivariable analysis, new-onset AF was associated with cardiovascular adverse events (hazard ratio: 1.09, 95% confidence interval: 1.03-1.15), after adjustment for age, hypertension, and right and left ventricular structure and function.

Conclusions

Patients with COA were at risk for developing AF at a relatively young age (median age: 36 years), and AF was associated with cardiovascular adverse outcomes. There is a need to target the modifiable risk factors for AF to reduce the adverse outcomes associated with AF.

Left atrial mechanical dispersion and left atrial stiffness predicts recurrence of atrial fibrillation: In patients with moderate-severe rheumatic mitral stenosis

AIMS

The aim of this study was to evaluate the relationship between preoperative left atrial function and recurrence of atrial fibrillation (AF) after mitral valve surgery and Cox Maze procedure in patients with moderate-to-severe rheumatic mitral stenosis (MS) combined with AF, in order to facilitate clinical risk stratification and to guide treatment strategies.

METHODS AND RESULTS

Patients with moderate-to-severe rheumatic MS attending Beijing Anzhen Hospital of Capital Medical University from April 2022 to September 2023 were prospectively collected, and all of them underwent transthoracic two-dimensional speckle-tracking echocardiography to assess left atrial structure and function before undergoing mitral valve surgery and Cox Maze procedure and postoperative follow-up. 121 patients were enrolled, of whom 77.69 % (94/121) were female, with a median follow-up time of 9.56 ± 1.83 months, and 48 patients (39.7 %, 48/121) had postoperative recurrence of AF. Preoperative left atrial stiffness index (LASI) [3.76(3.10-5.44) vs. 2.41(1.75-3.33), P < 0.001] and left atrial mechanical dispersion (SD-TPS) (15.84 ± 5.92vs. 11.58 ± 5.96, P = 0.001) were significantly higher in the postoperative AF recurrence group than in the without recurrence group; Multivariable cox regression analysis showed that LASI>3.15 and SD -TPS > 13.2 were associated with independent risk factors for AF recurrence (hazard ratio = 2.957, 95 %CI,1.366-6.399, P = 0.006 and hazard ratio = 2.892, 95 %CI,1.381-6.057, P = 0.005).

CONCLUSION

LASI and SD-TPS were effective predictors of postoperative recurrence of AF in patients with moderate-to-severe rheumatic MS, and LASI >3.15 and SD-TPS% >13.2 were independent influences on the recurrence of AF after Cox Maze in this group of patients.

Evaluation of Cardiac Function Recovery in Patients with Paroxysmal Atrial Fibrillation after Catheter Radiofrequency Ablation Using Two-Dimensional Speckle Tracking Imaging and Real-Time Three-Dimensional Echocardiography

INTRODUCTION

The aim of this study was to evaluate the utility of 2D-STI and real-time three-dimensional echocardiography (RT-3DE) in assessing changes in left atrial (LA) structure and function in patients with paroxysmal atrial fibrillation (PAF) post-radiofrequency catheter ablation (RFCA).

METHODS

A retrospective analysis was conducted on 44 PAF patients who underwent RFCA at BA Hospital from March 2022 to March 2023. An age- and gender-matched control group of 32 healthy individuals was also included. Comprehensive echocardiographic parameters including LA dimensions (LAAPD, LALRD), volumes (LAVmin, LAVmax), ejection fraction (LAEF), and tissue velocities (a', Ar) were compared between groups. Post-RFCA changes in these parameters were also assessed at 1, 3, and 6 months.

RESULTS

Pre-RFCA, PAF patients demonstrated larger LA dimensions and volumes with reduced LAEF and tissue velocities compared to controls. Post-RFCA, there was a significant improvement in LAEF and left ventricular ejection fraction at 1, 3, and 6 months, with the most pronounced changes observed at 6 months. LA dimensions increased initially but then decreased from 1 to 6 months post-RFCA. Notably, strain rate (SRS, SRE, SRA) measurements in various LA segments improved progressively, with the most significant enhancements at 6 months, suggesting improved atrial mechanics.

CONCLUSION

The application of 2D-STI and RT-3DE provides a quantitative means to evaluate the structural and functional changes in the LA of PAF patients following RFCA. The progressive improvements in LA dimensions, volumes, and strain measurements up to 6-month post-RFCA indicate the potential of these techniques in monitoring treatment efficacy and patient recovery.

INTRODUCTION

The aim of this study was to evaluate the utility of 2D-STI and real-time three-dimensional echocardiography (RT-3DE) in assessing changes in left atrial (LA) structure and function in patients with paroxysmal atrial fibrillation (PAF) post-radiofrequency catheter ablation (RFCA).

METHODS

A retrospective analysis was conducted on 44 PAF patients who underwent RFCA at BA Hospital from March 2022 to March 2023. An age- and gender-matched control group of 32 healthy individuals was also included. Comprehensive echocardiographic parameters including LA dimensions (LAAPD, LALRD), volumes (LAVmin, LAVmax), ejection fraction (LAEF), and tissue velocities (a', Ar) were compared between groups. Post-RFCA changes in these parameters were also assessed at 1, 3, and 6 months.

RESULTS

Pre-RFCA, PAF patients demonstrated larger LA dimensions and volumes with reduced LAEF and tissue velocities compared to controls. Post-RFCA, there was a significant improvement in LAEF and left ventricular ejection fraction at 1, 3, and 6 months, with the most pronounced changes observed at 6 months. LA dimensions increased initially but then decreased from 1 to 6 months post-RFCA. Notably, strain rate (SRS, SRE, SRA) measurements in various LA segments improved progressively, with the most significant enhancements at 6 months, suggesting improved atrial mechanics.

CONCLUSION

The application of 2D-STI and RT-3DE provides a quantitative means to evaluate the structural and functional changes in the LA of PAF patients following RFCA. The progressive improvements in LA dimensions, volumes, and strain measurements up to 6-month post-RFCA indicate the potential of these techniques in monitoring treatment efficacy and patient recovery.

Beyond Clinical Factors: Harnessing Artificial Intelligence and Multimodal Cardiac Imaging to Predict Atrial Fibrillation Recurrence Post-Catheter Ablation

Atrial fibrillation (AF) is the most common type of cardiac arrhythmia, with catheter ablation being a key alternative to medical treatment for restoring normal sinus rhythm. Despite advances in understanding AF pathogenesis, approximately 35% of patients experience AF recurrence at 12 months after catheter ablation. Therefore, accurate prediction of AF recurrence occurring after catheter ablation is important for patient selection and management. Conventional methods for predicting post-catheter ablation AF recurrence, which involve the use of univariate predictors and scoring systems, have played a supportive role in clinical decision-making. In an ever-changing landscape where technology is becoming ubiquitous within medicine, cardiac imaging and artificial intelligence (AI) could prove pivotal in enhancing AF recurrence predictions by providing data with independent predictive power and identifying key relationships in the data. This review comprehensively explores the existing methods for predicting the recurrence of AF following catheter ablation from different perspectives, including conventional predictors and scoring systems, cardiac imaging-based methods, and AI-based methods developed using a combination of demographic and imaging variables. By summarising state-of-the-art technologies, this review serves as a roadmap for developing future prediction models with enhanced accuracy, generalisability, and explainability, potentially contributing to improved care for patients with AF.

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.

Epicardial Atrial Fat at Cardiac Magnetic Resonance Imaging and AF Recurrence after Transcatheter Ablation

The relationship between epicardial adipose tissue (EAT) and atrial fibrillation (AF) has gained interest in recent years. The previous literature on the topic presents great heterogeneity, focusing especially on computed tomography imaging. The aim of the present study is to determine whether an increased volume of left atrial (LA) EAT evaluated at routine pre-procedural cardiac magnetic resonance imaging (MRI) relates to AF recurrences after catheter ablation. A total of 50 patients undergoing AF cryoballoon ablation and pre-procedural cardiac MRI allowing quantification of LA EAT were enrolled. In one patient, the segmentation of LA EAT could not be achieved. After a median follow-up of 16.0 months, AF recurrences occurred in 17 patients (34%). The absolute volume of EAT was not different in patients with and without AF recurrences (10.35 mL vs. 10.29 mL; p-value = 0.963), whereas the volume of EAT indexed on the LA volume (EATi) was lower, albeit non-statistically significant, in patients free from arrhythmias (12.77% vs. 14.06%; p-value = 0.467). The receiver operating characteristic curve testing the ability of LA EATi to predict AF recurrence after catheter ablation showed sub-optimal performance (AUC: 0.588). The finest identified cut-off of LA EATi was 10.65%, achieving a sensitivity of 0.5, a specificity of 0.82, a positive predictive value of 0.59 and a negative predictive value of 0.76. Patients with values of LA EATi lower than 10.65% showed greater survival, free from arrhythmias, than patients with values above this cut-off (84% vs. 48%; p-value = 0.04). In conclusion, EAT volume indexed on the LA volume evaluated at cardiac MRI emerges as a possible independent predictor of arrhythmia recurrence after AF cryoballoon ablation. Nevertheless, prospective studies are needed to confirm this finding and eventually sustain routine EAT evaluation in the management of patients undergoing AF catheter ablation.

Left atrial mechanics evaluated by two-dimensional strain analysis: alterations in essential hypertension

BACKGROUND

Hypertension is a cardiovascular risk factor that predisposes to cardiac structural alterations namely increased left ventricular (LV) wall thickness, reduced LV compliance and diastolic dysfunction, with consequent left atrial (LA) dilation and functional impairment. In this article, we evaluated differences in left atrial structure and function using two-dimensional speckle tracking echocardiography in patients with hypertension compared with controls.

METHODS

This was a retrospective cross-sectional study of 208 hypertensive patients and 157 controls who underwent a comprehensive transthoracic echocardiogram. Patients with hypertension were stratified by the presence of left ventricular hypertrophy (LVH).

RESULTS

Non-LVH hypertension patients had lower left atrial reservoir strain (LAS RES ) (34.78 ± 29.78 vs. 29.78 ± 6.08; P  = 0.022) and conduit strain (LAS CD ) (19.66 ± 7.29 vs. 14.23 ± 4.59; P  = 0.014) vs. controls despite similar left atrial volumes (LAV) . Left atrial contractile strain (LAS CT ) was not significantly different between non-LVH hypertension patients and controls (15.12 ± 3.77 vs. 15.56 ± 3.79; P  = 0.601). Left atrial mechanical dispersion was significantly higher in the LVH group compared with the non-LVH hypertension group (42.26 ± 13.01 vs. 50.06 ± 14.95; P  = 0.009). In multivariate regression analysis, LVH correlated with left atrial mechanical dispersion ( P  = 0.016). An age-hypertension interaction independently correlated with LAS CT ( P  < 0.001).

CONCLUSION

Hypertension results in functional left atrial changes even before development of LV hypertrophy and structural left atrial changes with increased left atrial volume. We demonstrate both a likely hypertension-associated left atrial myopathy that prevents age-related compensatory increase in left atrial contractile function, and impact of LVH in hypertension on left atrial dyssynchrony.

Left Atrial Low-Voltage Areas Predict the Risk of Atrial Fibrillation Recurrence after Radiofrequency Ablation

Atrial fibrillation (AF), the most frequently encountered arrhythmia worldwide, is associated with increased cardiovascular morbidity and mortality. Left atrial (LA) and antral region of the pulmonary veins (PVs) remodeling are risk factors for AF perpetuation. Among the methods of LA fibrosis quantification, bipolar voltage mapping during three-dimensional electro-anatomical mapping is less studied. The main aim of this study was to analyze the relationship between the degree of LA fibrosis quantified in low-voltage areas and the efficacy of AF radiofrequency catheter ablation. All consecutive patients with AF ablation were included, and the degree of LA fibrosis was measured based on the low-voltage areas in the LA and the antral region of PVs (<0.5 mV for patients in sinus rhythm and <0.25 mV for patients in AF at the time of the ablation procedure). The efficacy of AF ablation was determined by the rate of recurrence after a blanking period of three months. A total of 106 patients were included; from these, 38 (35.8%) had AF recurrence after RF ablation, while 68 (64.2%) were free of events. The area and percentage of LA fibrosis were significantly higher in the patients with AF recurrence (p = 0.018 and p = 0.019, respectively). However, no significant differences were found between the patients with and without AF recurrence in terms of the area and percentage of PVs fibrosis (p = 0.896 and p = 0.888, respectively). Moreover, LA fibrosis parameters proved to be excellent predictors for AF recurrence (areas under the curve of 0.834 and 0.832, respectively, p < 0.001) even after adjustment for LA indexed volume and CHA2DS2-VASc score. In conclusion, LA fibrosis measured on bipolar voltage maps increases the risk of AF recurrence after the RF catheter ablation procedure.

Functional reserve and contractile phenotype of atrial myocardium from patients with atrial remodeling without and with atrial fibrillation

Atrial contractility and functional reserve in atrial remodeling (AR) without (AR/-AF) or with atrial fibrillation (AR/+AF) are not well characterized. In this study, functional measurements were performed in right atrial muscle strips (n = 71) obtained from patients (N = 22) undergoing routine cardiac surgery with either no AR [left atrial (LA) diameter < 40 mm and no history of AF (hAF)], AR/-AF (LA diameter ≥ 40 mm, no hAF), or AR/+AF (hAF and LA diameter ≥ 40 mm or LAEF < 45%). AR/-AF and AR/+AF were associated with a prolongation of half-time-to-peak (HTTP, P < 0.001) and time-to-peak (TTP) contraction (P < 0.01) when compared with no AR. This effect was seen at baseline and during β-adrenergic stimulation with isoproterenol (Iso). Early relaxation assessed by half-relaxation time (HRT) was prolonged in AR/-AF (P = 0.03) but not in AR/+AF when compared with no AR at baseline, but this delay in relaxation in AR/-AF was attenuated with Iso. Late relaxation (τ) did not differ between AR/-AF and no AR but was consistently shorter in AR/+AF than no AR before (P = 0.04) and during Iso (P = 0.01), indicating accelerated late relaxation in AR/+AF. Relative force increase during Iso was higher (P = 0.01) and more dispersed (P = 0.047) in patients with AR/+AF. Relative adrenergic response was unaltered in the myocardium of patients with AR/-AF and AR/+AF. In conclusion, AR/-AF and AR/+AF are associated with changes in myocardial inotropic reserve and contractility. The changes are particularly pronounced in patients with AR/+AF, suggesting that the progression from AR/-AF to AR/+AF is associated with progressive alterations in atrial function that may contribute to arrhythmogenesis.NEW & NOTEWORTHY Mechanical alterations in atrial remodeling without (AR/-AF) and with atrial fibrillation (AR/+AF) have not been studied in detail in human atrial tissue preparations. To our knowledge, this is the first study to compare the mechanical phenotype and inotropic reserve in human atrial myocardial preparations from patients with no atrial remodeling, AR/-AF, and AR/+AF. We identify specific patterns of contractile dysfunction and heterogeneity for both, AR/-AF and AR/+AF, indicating the progression of atrial disease.

Left atrial strain superior to structural remodeling in identifying occult atrial fibrillation

OBJECTIVE

Occult atrial fibrillation (AF) is a significant risk factor for occult stroke but is difficult to detect. Myocardial strain, based on speckle tracking echocardiography (STE), can detect subclinical changes in left atrial (LA) function. This study aimed to investigate the diagnostic value of LA strain in identifying asymptomatic AF patients with normal electrocardiograms and healthy volunteers.

METHODS

A total of 354 subjects were retrospectively enrolled. Patients were divided into two groups based on whether they had AF during echocardiography. Patients with sinus rhythm during echocardiography were further divided into healthy control group and occult AF group. Patients with AF during echocardiography were further divided into paroxysmal AF group and persistent AF group. LA mechanical function measured by STE was compared between patients with asymptomatic AF and volunteers. Conventional echocardiographic indicators were measured. The diagnostic value of LA strain for identifying asymptomatic AF was assessed by univariate and multivariate regression analysis and receiver operating characteristic (ROC) curves.

RESULTS

Occult AF patients had higher NT-proBNP levels, larger RA area, larger LAVmax and decreased LAEF than control group. However, occult AF patients had lower NT-proBNP levels, RA area and LAVmax and higher LAEF than paroxysmal and persistent AF. The measured LA reservoir strain (LASr), LA conduit strain (LAScd), LA contraction strain (LASct) of occult AF group was significantly lower than that of control group. However, occult AF patients had preserved LAScd and LASct than paroxysmal and persistent AF. RA area, LAEF and LASr were remarkable correlation with occult AF after adjustment for NT-proBNP, LAVmax, and LAScd. The area under curve of ROC for LASr was the greatest among RA area, LAEF and LASr, with a cut-off value of 34.1% (sensitivity: 75.4%, specificity: 87.6%).

CONCLUSION

LASr can identify occult AF in the asymptomatic population. Patients with LASr values ≤34.1% have a higher incidence of occult cardiac dysfunction. These findings help identify patients with occult AF and further risk stratification for the AF population.

Brady- and tachyarrhythmias detected by continuous rhythm monitoring in paroxysmal atrial fibrillation

OBJECTIVE

Atrial fibrillation (AF) is associated with adverse events including conduction disturbances, ventricular arrhythmias and sudden death. The aim of this study was to examine brady- and tachyarrhythmias using continuous rhythm monitoring in patients with paroxysmal self-terminating AF (PAF).

METHODS

In this multicentre observational substudy to the Reappraisal of Atrial Fibrillation: interaction between hyperCoagulability, Electrical remodelling and Vascular destabilisation in the progression of AF (RACE V), we included 392 patients with PAF and at least 2 years of continuous rhythm monitoring. All patients received an implantable loop recorder, and all detected episodes of tachycardia ≥182 beats per minute (BPM), bradycardia ≤30 BPM or pauses ≥5 s were adjudicated by three physicians.

RESULTS

Over 1272 patient-years of continuous rhythm monitoring, we adjudicated 1940 episodes in 175 patients (45%): 106 (27%) patients experienced rapid AF or atrial flutter (AFL), pauses ≥5 s or bradycardias ≤30 BPM occurred in 47 (12%) patients and in 22 (6%) patients, we observed both episode types. No sustained ventricular tachycardias occurred. In the multivariable analysis, age >70 years (HR 2.3, 95% CI 1.4 to 3.9), longer PR interval (HR 1.9, 1.1-3.1), CHA2DS2-VASc score ≥2 (HR 2.2, 1.1-4.5) and treatment with verapamil or diltiazem (HR 0.4, 0.2-1.0) were significantly associated with bradyarrhythmia episodes. Age >70 years was associated with lower rates of tachyarrhythmias.

CONCLUSIONS

In a cohort exclusive to patients with PAF, almost half experienced severe bradyarrhythmias or AF/AFL with rapid ventricular rates. Our data highlight a higher than anticipated bradyarrhythmia risk in PAF.

TRIAL REGISTRATION NUMBER

NCT02726698.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Atrial cardiomyopathy: Current and future imaging methods for assessment of atrial structure and function

Changes in atrial size and function have historically been considered a surrogate marker of ventricular dysfunction. However, it is now recognized that atrial cardiomyopathy (ACM) may also occur as a primary myocardial disorder. Emerging evidence that ACM is a major risk factor for atrial fibrillation, heart failure, and thromboembolic stroke, has highlighted the significance of this disorder and the need for better assessment of atrial metrics in clinical practice. Key barriers in this regard include a lack of standardized criteria or hierarchy for the diagnosis of ACM and lack of consensus for the most accurate phenotyping methods. In this article we review existing literature on ACM, with a focus on current and future non-invasive imaging methods for detecting abnormalities of atrial structure and function. We discuss the relative advantages and disadvantages of transthoracic echocardiography and cardiac magnetic resonance imaging for assessing a range of parameters, including atrial size and contractile function, strain, tissue characteristics, and epicardial adipose tissue. We will also present the potential application of novel imaging methods such as sphericity index and four- or five-dimensional flow.

Development and Validation of a Postoperative Prognostic Nomogram to Predict Recurrence in Patients with Persistent Atrial Fibrillation: A Retrospective Cohort Study

Background: Patients with persistent atrial fibrillation (PsAF) have a high risk of recurrence after catheter radiofrequency ablation. Nevertheless, no effective prognostic tools have been developed to identify these high-risk patients to date. This study sought to develop and validate a simple linear predictive model for predicting postoperative recurrence in patients with PsAF.

Methods: From June 2013 to June 2021, patients with PsAF admitted to our hospital were enrolled in this single-center, retrospective, observational study. The characteristics substantially associated with recurrence in patients with PsAF were screened through univariate and multivariate logistic regression analysis. The receiver operating characteristic curve was used to assess the predictive significance of the nomogram model after nomogram development. Furthermore, to assess the clinical value of the nomogram, we performed calibration curve and decision curve analyses.

Results: A total of 209 patients were included in the study, 42 (20.10%) of whom were monitored up to 1 year for recurrent AF. The duration of AF episodes, left atrial diameter, BMI, CKMB, and alcohol consumption were found to be independent risk factors (P<0.05) and were integrated into the nomogram model development. The area under the curve was 0.895, the sensitivity was 93.3%, and the specificity was 71.4%, thus indicating the model’s excellent predictive ability. The C-index of the predictive nomogram model was 0.906. Calibration curve and decision curve analyses further revealed that the model had robust prediction and strong discrimination ability.

Conclusion: This simple, practical, and innovative nomogram can help clinicians in evaluation of the risk of PsAF recurrence after catheter ablation, thus facilitating preoperative evaluation, postoperative monitoring and ultimately the construction of more personalized therapeutic protocols.

Left atrial strain and clinical outcome in patients with significant mitral regurgitation after surgical mitral valve repair

Background

This study aimed to investigate the prognostic value of left atrial (LA) strain in patients with significant mitral regurgitation (MR) after surgical mitral valve (MV) repair.

Methods

A total of 169 patients (age 55 ± 15 years, 88 men) with moderate or severe MR on echocardiogram at least 6 months after surgical MV repair for primary MR were studied. Two-dimensional, Doppler, and speckle tracking echocardiography including MR quantitative measures, chamber size, and LA strain were comprehensively analyzed. The primary outcome was a composite of cardiovascular death, heart failure hospitalization, and MV reoperation.

Results

During a median of 44.4 months [interquartile range (IQR): 18.7-70.3 months] of follow-up, 44 patients (26%) experienced clinical events; these patients had greater MR volume, elevated mean diastolic pressure gradient and pulmonary artery systolic pressure, and enlarged chamber size compared with patients who did not experience events. Patients with events showed significantly lower LA strain [13.3% (IQR: 9.3-23.8%) vs. 24.0% (IQR: 13.1-31.4%), p = 0.003] and higher MR volume/LA strain [3.09 ml/% (IQR: 2.06-5.80 ml/%) vs. 1.57 ml/% (IQR: 1.04-2.72 ml/%), p < 0.001] than those without events. MR volume/LA strain was a good predictor of clinical outcomes (cut-off 1.57 ml/%, area under the curve 0.754, p < 0.001). On multivariable Cox proportional analysis, MR volume/LA strain was independently associated with clinical outcomes (hazard ratio: 1.269, 95% confidence interval: 1.109-1.452, p < 0.001) along with pulmonary artery systolic pressure.

Conclusion

A measure of LA mechanical function relative to MR volume is associated with clinical outcomes in patients with significant MR after surgical MV repair.

Assessment of Left Atrial Structure and Function by Echocardiography in Atrial Fibrillation

Atrial fibrillation (AF) is the most common arrhythmia with significant morbidity and mortality. Exacerbated by the aging population, the prevalence of AF is gradually increasing. Accurate evaluation of structure and function of left atrium (LA) has important prognostic significance in patients with AF. Echocardiography is the imaging technique of first choice to assess LA structure and function due to its better availability, accessibility and safety over cardiac computed tomography and cardiac magnetic resonance. Therefore, the aim of this review is to summarize the recent research progress of evaluating LA size by three-dimensional echocardiography and LA function by speckle tracking echocardiography (STE) in predicting the occurrence and recurrence of AF and determining the risk of stroke in AF. In addition, we summarized the role of traditional echocardiography in detecting AF patients that are at high risk of heart failure or cardiovascular death.

Left atrial strain and recurrence of atrial fibrillation after thoracoscopic surgical ablation: a subanalysis of the AFACT study

To assess transthoracic echocardiographic (TTE) left atrial (LA) strain parameters and their association with atrial fibrillation (AF) recurrence after thoracoscopic surgical ablation (SA) in patients in sinus rhythm (SR) or in AF at baseline. Patients participating in the Atrial Fibrillation Ablation and Autonomic Modulation via Thoracoscopic Surgery trial were included. All patients underwent thoracoscopic pulmonary vein isolation with LA appendage exclusion and were randomized to ganglion plexus (GP) or no GP ablation. In TTEs performed before surgery, LA strain and mechanical dispersion (MD) of the LA reservoir and conduit phase in all patients, and of the contraction phase in patients in SR were obtained. Recurrence of AF was defined as any documented atrial tachyarrhythmia lasting > 30 s during one year of follow-up. Two hundred and four patients (58.6 ± 7.8 years, 73% male, 57% persistent AF) were included. At baseline TTE 121 (59%) were in SR and 83 (41%) had AF. Patients with AF recurrence had lower LA strain of the reservoir phase (13.0% vs. 16.6%; p =  < 0.001) and a less decrease in strain of the conduit phase (−9.0% vs. −11.8%; p = 0.006), regardless of rhythm. MD of the conduit phase was larger in patients with AF recurrence (79.4 vs. 43.5 ms; p = 0.012). Multivariate cox regression analysis demonstrated solely an association between LA strain of the reservoir phase and AF recurrence in patients in SR (HR 0.95, p = 0.046) or with AF (HR 0.90, p = 0.038). A reduction in LA strain of the reservoir phase prior to SA predicts recurrence of AF in both patients with SR or AF. Left atrial strain assessment may therefore add to a better patient selection for SA.

Global longitudinal strain and outcome after endoscopic mitral valve repair

Aims

Identification of heart failure (HF) patients with secondary mitral regurgitation (SMR) that benefit from mitral valve (MV) repair remains challenging. We have focused on the role of left ventricular global longitudinal strain (LV‐GLS) and reservoir left atrial longitudinal strain (LASr) for the prediction of long‐term survival and reverse remodelling in patients with SMR undergoing endoscopic MV repair.

Methods and results

The study population consisted of 110 patients (age 67 ± 11 years, 66% men) with symptomatic SMR undergoing isolated MV repair using a minimally invasive surgical approach. Speckle tracking‐derived LV‐GLS and LASr were assessed in apical views using vendor‐independent software. Over a median of 7.7 years (IQRs 2.9–11.2), 64 patients (58%) died. Significant reverse LV (↓ LVESVI >10 mL/m²), LA (↓ LAVI >10 mL/m²) remodelling or both were observed in 43 (39%), 37 (34%) and 19 (17%) patients, respectively. LV‐GLS (HR 0.68, 95% CI 0.58–0.79, P < 0.001) and LASr (HR 0.93, 95% CI 0.88–0.97, P < 0.01) but not LV ejection fraction (LVEF) and LA volume index (LAVi) emerged as independent predictors of all‐cause mortality in Cox regression analysis. LV‐GLS was the only independent predictor of LV reverse remodelling (OR 1.24, 95% CI 1.05–1.43, P < 0.001) whereas LAVi and LASr were both independent predictors of LA reverse remodelling (both P < 0.05). In patients with atrial fibrillation at baseline, only LASr was an independent predictor (P < 0.05) of LA reverse remodelling.

Conclusions

In patients with SMR undergoing endoscopic MV repair, LV‐GLS and LASr are independently associated with long‐term survival and reverse remodelling and may be helpful in selecting SMR patients who may benefit from this procedure.

Left Atrial Strain: Clinical Use and Future Applications-A Focused Review Article

Atrial cardiomyopathy represents a process of structural and functional changes affecting the atria and leading eventually to clinical manifestation of atrial fibrillation and risk of stroke. Multimodality imaging provides a comprehensive evaluation of atrial remodeling and plays a crucial role in the decision-making process in treatment strategy. This paper summarizes the current state of knowledge on the topic of left atrial strain imaging using two-dimensional speckle tracking echocardiography (2D-STE). We focus on our recently published data on left atrial remodeling assessed by 2D-STE versus high-density voltage mapping in patients with atrial fibrillation (AF).

From Left Atrial Dimension to Curved M-Mode Speckle-Tracking Images: Role of Echocardiography in Evaluating Patients with Atrial Fibrillation

Left atrial (LA) enlargement and dysfunction increase the risk of atrial fibrillation (AF). Traditional echocardiographic evaluation of the left atrium has been limited to dimensional and semi-quantification measurement of the atrial component of ventricular filling, with routine measurement of LA function not yet implemented. However, functional parameters, such as LA emptying fraction (LAEF), may be more sensitive markers for detecting AF-related changes than LA enlargement. Speckle-tracking echocardiography has proven to be a feasible and reproducible technology for the direct evaluation of LA function. The clinical application, advantages, and limitations of LA strain and strain rate need to be fully understood. Furthermore, the prognostic value and utility of this technique in making therapeutic decisions for patients with AF need further elucidation. Deep learning neural networks have been successfully adapted to specific tasks in echocardiographic image analysis, and fully automated measurements based on artificial intelligence could facilitate the clinical diagnostic use of LA speckle-tracking images for classification of AF ablation outcome. This review describes the fundamental concepts and a brief overview of the prognostic utility of LA size, LAEF, LA strain and strain rate analyses, and the clinical implications of the use of these measures.

The Predictive Value of Left Atrial Strain Following Transcatheter Aortic Valve Implantation on Anatomical and Functional Reverse Remodeling in a Multi-Modality Study

Introduction

Transcatheter aortic valve implantation (TAVI) can improve left ventricular (LV) mechanics and survival. Data on the predictive value of left atrial (LA) strain following TAVI are scarce. We aimed to evaluate the association of LA strain measured shortly post-TAVI with functional and anatomical reverse remodeling of the LA and LV, and its association with mortality.

Methods

We prospectively investigated 90 patients who underwent TAVI. Transthoracic echocardiography including strain analysis was performed shortly after TAVI and repeated 6 months later. CT angiography (CTA) was performed for pre-TAVI planning and 6 months post-TAVI. Speckle tracking echocardiography was used to determine LA peak reservoir strain (LASr) and LV global longitudinal strain (LV-GL), LA volume index (LAVi) was measured by TTE. LV mass index (LVMi) was calculated using CTA images. LA reverse remodeling was based on LASr and LAVi changes, whereas LV reverse remodeling was defined as an improvement in LV-GLS or a reduction of LVMi. The association of severely reduced LASr (&lt;20%) at baseline with changes (Δ) in LASr, LAVi, LV-GLS and LVMi were analyzed using linear regression, and Cox proportional hazard model for mortality.

Results

Mean LASr and LV-GLS were 17.7 ± 8.4 and −15.3 ± 3.4% at baseline and 20.2 ± 10.2 and −16.6 ± 4.0% at follow-up (p = 0.024 and p &lt; 0.001, respectively). Severely reduced LASr at baseline was associated with more pronounced ΔLASr (β = 5.24, p = 0.025) and LVMi reduction on follow-up (β = 5.78, p = 0.036), however, the majority of the patients had &lt;20% LASr on follow-up (44.4%). Also, ΔLASr was associated with ΔLV-GLS (adjusted β = 2.10, p &lt; 0.001). No significant difference in survival was found between patients with baseline severely reduced LASr (&lt;20%) and higher LASr (≥20%) (p = 0.054).

Conclusion

LV reverse remodeling based on LVMi was present even in patients with severely reduced LASr following TAVI, although extensive LA damage based on LA strain was demonstrated by its limited improvement over time.

Clinical Trial Registration

(ClinicalTrials.gov number: NCT02826200).

Assessing left atrial function in patients with atrial fibrillation and valvular heart disease using cardiovascular magnetic resonance imaging

Background

Atrial fibrillation (AF) is common arrhythmia in valvular heart disease (VHD) and is associated with adverse outcomes.

Hypothesis

To evaluate the left atrial (LA) function in patients with AF‐VHD by cardiovascular magnetic resonance imaging feature tracking (CMR‐FT) using LA strain (ε_s/ε_e/ε_a) and their corresponding strain rate (SRs/SRe/SRa).

Methods

This was a retrospective cross‐sectional inter‐reader and intra‐reader reproducibility conducted from July 1, 2020, to January 31, 2021. A total of 39 patients with AF‐VHD (rheumatic heart valvular disease [RHVD] [n = 22], degenerative heart valvular disease [DHVD] [n = 17]) underwent MRI scans performed with drug‐controlled heart rate before correcting the rhythm and valves through maze procedure. Fifteen participants with normal cardiac MRI were included as healthy control. ε_s/SRs, ε_e/SRe, and ε_a/SRa, corresponding to LA reservoir, conduit, and booster‐pump function, were assessed using Feature Tracking software (CVI42 v5.12.1).

Results

Compared with healthy controls, LA global strain parameters (ε_s/ε_e/ε_a/SRs/SRe/SRa) were significantly decreased (all p < 0.001), while LA size and volume were increased in AF‐VHD group (all p < 0.001). In the subgroup, RHVD group showed lower LA total ejection fraction (LATEF) and strain data than DHVD group (12.6% ± 3.3% vs. 19.4 ± 8.6, p = 0.001). Decreased LATEF was significantly related to altered LA strain and strain rate, especially in ε_s, ε_e, and SRs (Pearson/Spearman r/ρ = 0.856/0.837/0.562, respectively; all p < 0.001). Interstudy and intrastudy reproducibility were consistent for LA volumetry and strain parameters (intraclass correlation coefficient: 0.88–0.99).

Conclusions

CMR‐FT can be used to assess the LA strain parameters, and identify LA dysfunction and deformation noninvasively, which could be a helpful functional imaging biomarker in the clinical treatment of AF‐VHD.

Left atrial dysfunction may precede left atrial enlargement and abnormal left ventricular longitudinal function: a cardiac MR feature tracking study

Background

The role of the dysfunction of left atrium in the occurrence and development of cardiovascular disease has been gradually recognized. We aim to compare the impact on left atrial (LA) function between patients with hypertrophic cardiomyopathy (HCM) and hypertension (HTN) without LA enlargement using cardiovascular magnetic resonance feature tracking (CMR-FT), and if possible, explore the capability of LA function for providing clinical implication and predicting clinical adverse events in the early stage of cardiovascular disease.

Methods

Consecutive 60 HCM patients and 60 HTN patients with normal LA size among 1413 patients who underwent CMR were retrospectively analyzed as well as 60 controls. Left atrial and ventricular functions were quantified by volumetric and CMR-FT derived strain analysis from long and short left ventricular view cines. The primary endpoint was a composite of all-cause death, stroke, new-onset or worsening heart failure to hospitalization, and paroxysmal or persistent atrial fibrillation.

Results

Compared to the controls, both HTN and HCM participants had impaired LA reservoir function (εs) and conduit function (εe) with the different stage of LA booster pump dysfunction (εa). LA strain was more sensitive than LV longitudinal strain (GLS) for evaluate primary endpoint (εs: 33.9% ± 7.5 vs. 41.2% ± 14.3, p = 0.02; εe: 13.6% ± 6.2 vs. 17.4% ± 10.4, p = 0.03; εa: 20.2% ± 6.0 vs. 23.7% ± 8.8, p = 0.07; GLS: -19.4% ± 6.4 vs. -20.0% ± 6.8, p = 0.70, respectively). After a mean follow-up of 6.8 years, 23 patients reached primary endpoint. Cox regression analyses indicated impaired LA reservoir and booster pump strain were associated with clinical outcomes in patients at the early stage of HTN and HCM (p < 0.05).

Conclusions

CMR-FT-derived strain is a potential and robust tool in demonstrating impaired LA mechanics, quantifying LA dynamics and underlining the impacts on LA-LV coupling in patients with HTN and HCM without LA enlargement. The corresponding LA dysfunction is a promising metric to assess clinical implication and predict prognosis at the early stage, superior to GLS.

Clinical Utility of Left Atrial Asynchrony and Mechanical Function in Patients with Hypertrophic Cardiomyopathy

BACKGROUND

The aim of this study was to examine whether left atrial dispersion and left atrial strain as measured by speckle tracking echocardiography and clinical parameters are predictors of the development of atrial fibrillation in patients with hypertrophic cardiomyopathy.

METHODS

A total of 151 patients (69% male, mean age 48.9 ± 14.2 years) with hypertrophic cardiomyopathy were included in the study. The patients' demographic, clinical, electrocardiographic, 2-dimensional classic and speckle tracking echocardiographic data were collected. Atrial fibrillation was identified by 12-lead electrocardiograms or 24-72 hours of Holter recordings during the follow-up period. Atrial dispersion was defined as the standard deviation of time to peak strain in 12 left atrial segments.

RESULTS

During the follow-up period, 40 patients (26%) developed atrial fibrillation. Peak atrial longitudinal strain (16.8 ± 6 vs. 22.1 ± 6.6, p ≤ 0.001) was significantly lower in the patients who developed atrial fibrillation than in those who did not. However, atrial dispersion was significantly higher in the group which developed atrial fibrillation (61 [46.7,78.6] vs. 41.3 [30.6-51], p ≤ 0.001). In multivariate Cox regression analysis, atrial dispersion (msn) (hazard ratio: 1.019, 95% confidence interval: 1.004-1.033, p = 0.01), peak atrial longitudinal strain, and age were found to be independent predictors of atrial fibrillation.

CONCLUSIONS

In patients with hypertrophic cardiomyopathy, atrial dispersion, peak atrial longitudinal strain and age are predictive of the development of atrial fibrillation. Atrial dispersion measured by a speckle tracking-based method may provide further information on left atrial function in patients with hypertrophic cardiomyopathy or other disease states.

Echocardiographic Assessment of Atrial Function: From Basic Mechanics to Specific Cardiac Diseases

The left and right atria serve as buffer chambers to control the flow of venous blood for ventricular filling. If an atrium is absent, blood does not flow effectively into the ventricle, leading to venous blood retention and low cardiac output. The importance of atrial function has become increasingly recognized, because left atrial (LA) function contributes to cardiac performance, and loss of LA function is associated with heart failure. LA volume change has been used for LA function assessment in experimental and clinical studies. In conjunction with LA pressure, the LA pressure–volume relationship provides a better understanding of LA mechanics. LA strain measurement by speckle tracking echocardiography was introduced to evaluate three components of LA function as a (booster) pump, reservoir and conduit. Furthermore, increasing evidence supports the theory that LA reservoir strain has prognostic utility in various cardiac diseases. In this review, we summarize LA contribution to maintain cardiac performance by evaluating LA function with echocardiography according to our experiences and previous reports. Furthermore, we discuss LA dysfunction in challenging cardiac diseases of cardiac amyloidosis and adult congenital heart disease.

Left atrial evaluation by cardiovascular magnetic resonance: sensitive and unique biomarkers

Left atrial (LA) imaging is still not routinely used for diagnosis and risk stratification, although recent studies have emphasized its importance as an imaging biomarker. Cardiovascular magnetic resonance is able to evaluate LA structure and function, metrics that serve as early indicators of disease, and provide prognostic information, e.g. regarding diastolic dysfunction, and atrial fibrillation (AF). MR angiography defines atrial anatomy, useful for planning ablation procedures, and also for characterizing atrial shapes and sizes that might predict cardiovascular events, e.g. stroke. Long-axis cine images can be evaluated to define minimum, maximum, and pre-atrial contraction LA volumes, and ejection fractions (EFs). More modern feature tracking of these cine images provides longitudinal LA strain through the cardiac cycle, and strain rates. Strain may be a more sensitive marker than EF and can predict post-operative AF, AF recurrence after ablation, outcomes in hypertrophic cardiomyopathy, stratification of diastolic dysfunction, and strain correlates with atrial fibrosis. Using high-resolution late gadolinium enhancement (LGE), the extent of fibrosis in the LA can be estimated and post-ablation scar can be evaluated. The LA LGE method is widely available, its reproducibility is good, and validations with voltage-mapping exist, although further scan-rescan studies are needed, and consensus regarding atrial segmentation is lacking. Using LGE, scar patterns after ablation in AF subjects can be reproducibly defined. Evaluation of 'pre-existent' atrial fibrosis may have roles in predicting AF recurrence after ablation, predicting new-onset AF and diastolic dysfunction in patients without AF. LA imaging biomarkers are ready to enter into diagnostic clinical practice.

Echocardiographic diagnosis of atrial cardiomyopathy allows outcome prediction following pulmonary vein isolation

BACKGROUND

Relevant atrial cardiomyopathy (ACM), defined as a left atrial (LA) low-voltage area ≥ 2 cm2 at 0.5 mV threshold on endocardial contact mapping, is associated with new-onset atrial fibrillation (AF), higher arrhythmia recurrence rates after pulmonary vein isolation (PVI), and an increased risk of stroke. The current study aimed to assess two non-invasive echocardiographic parameters, LA emptying fraction (EF) and LA longitudinal strain (LAS, during reservoir (LASr), conduit (LAScd) and contraction phase (LASct)) for the diagnosis of ACM and prediction of arrhythmia outcome after PVI.

METHODS

We prospectively enrolled 60 consecutive, ablation-naive patients (age 66 ± 9 years, 80% males) with persistent AF. In 30 patients (derivation cohort), LA-EF and LAS cut-off values for the presence of relevant ACM (high-density endocardial contact mapping in sinus rhythm prior to PVI at 3000 ± 1249 sites) were established in sinus rhythm and tested in a validation cohort (n = 30). Arrhythmia recurrence within 12 months was documented using 72-h Holter electrocardiograms.

RESULTS

An LA-EF of < 34% predicted ACM with an area under the curve (AUC) of 0.846 (sensitivity 69.2%, specificity 76.5%) similar to a LASr < 23.5% (AUC 0.878, sensitivity 92.3%, specificity 82.4%). In the validation cohort, these cut-offs established the correct diagnosis of ACM in 76% of patients (positive predictive values 87%/93% and negative predictive values 73%/75%, respectively). Arrhythmia recurrence in the entire cohort was significantly more frequent in patients with LA-EF < 34% and LASr < 23.5% (56% vs. 29% and 55% vs. 26%, both p < 0.05).

CONCLUSION

The echocardiographic parameters LA-EF and LAS allow accurate, non-invasive diagnosis of ACM and prediction of arrhythmia recurrence after PVI.

Echocardiographic assessment of left atrial function for prediction of efficacy of catheter ablation for atrial fibrillation

Proper selection for catheter ablation (CA) for atrial fibrillation (AF) is still an issue. Echocardiographic assessment of left atrium (LA) is complex and challenging. Speckle tracking echocardiography (STE) with recent standardized LA deformation analysis allows for the quantitative assessment of various LA function parameters. We aimed to assess the value of detailed evaluations of LA function using STE in patients with non-valvular AF without structural heart disease to predict the outcomes after CA for AF. Secondary aim was to analyze the prediction of CA efficacy in patients with normal LA dimension in baseline echocardiography.We studied with transthoracic and transesophageal echocardiography 82 patients (58% males, mean age 57.3 ± 9.5 years) with non-valvular paroxysmal AF without structural heart disease scheduled for CA. Peak longitudinal LA strain (LAS) and strain rate (LASR) during the reservoir (r), conduit (cd) and contraction (ct) phases were measured by STE before the procedure. Patients were followed for 1 year using serial 4 to 7 day Holter ECG monitoring.Complete freedom from any AF recurrence was achieved in 44 (54%) patients. All patients had normal left ventricular systolic and diastolic function and 53 (65%) of them had not enlarged LA. In the multivariable logistic regression analysis, global left atrial reservoir strain (LASr) was identified as an independent predictor of CA efficacy (OR [95% CI]: 1.35 [1.17-1.55], P < .0001). The opportunity of CA success was 135 fold higher for each 1% increase in global LASr.The receiver operating characteristic (ROC) analysis identified global LASr and left atrial conduit strain (LAScd) as the most powerful parameters for predicting of CA outcome with an area under the curve of 0.896 and 0.860, respectively, in the whole study group, and 0.922 and 0.938, respectively, in patients with not enlarged LA.In patients with paroxysmal AF and normal standard echocardiographic assessment, parameters reflecting LA compliance - reservoir and conduit strain, are independent and strong predictors of CA outcome.

Assessment of atria function after percutaneous closure of atrial septal defect using 2D speckle tracking echocardiography

BACKGROUND

Percutaneous occlusion of atrial septal defect (ASD) has recently become a standard therapeutic strategy, but little is known about atria function thereafter. Strain analysis by two-dimensional speckle tracking echocardiography (2D-STE) is considered to be a new tool to assess myocardial function.

METHODS

This study aimed to evaluate atria function by quantifying longitudinal strain in patients with chronic RV volume overload due to ASD before and after percutaneous closure using 2D-STE. 28 consecutive patients underwent percutaneous closure of ASD (18 female, 10 male) were examined, clinical and echocardiographic evaluation one day before, 1 day, and one month after percutaneous closure of ASD. Peak longitudinal systolic strain and strain rate of both atria were analyzed by 2D-STE.

RESULTS

Mean age of the patients was 15.07 ± 8.39 years; mean diameter of ASD was 16.01 ± 2.78 mm; left atrium (LA) diameter significantly increased after ASD closure; and peak longitudinal strain of RA increased significantly one day and one month after ASD closure (48. 77 ± 4.40, vs.55.36 ± 3.70 and, vs. 62.13 ± 3.81%, p = 0.001). LA longitudinal strain significantly decreased after ASD closure (42.55 ± 4.57, vs. 34.79 ± 3.20%, p = 0.001). Furthermore, negative correlation was found between the size of the ASD and delta LA systolic strain and strain rate.

CONCLUSIONS

2D-STE can be considered a feasible and simple technique for assessment of atrial deformation in ASD patients, and it useful to assess the effect of percutaneous ASD closure on atrial reservoir function by measuring peak atrial longitudinal strain.

The Prognostic Value of Left Atrial Reservoir Functional Indices Measured by Three-Dimensional Speckle-Tracking Echocardiography for Major Cardiovascular Events

BACKGROUND

Left atrial (LA) volume and left ventricular longitudinal strain (LVLS) have significant prognostic values for major cardiovascular events (MACEs). Prognostic values of LA reservoir functional indices measured by 3-dimensional (3D) speckle-tracking echocardiography (STE) were evaluated.

METHODS AND RESULTS

A total of 264 patients, who underwent 2-dimensional (2D) echocardiography and 3DSTE for various underlying heart diseases, were followed up to record MACE. After a mean follow up of 547±435 days, 30 patients developed MACE: 7 cardiac deaths, 6 strokes, 1 non-fatal myocardial infarction, and 22 admissions for heart failure (5 of these had cardiac death after discharge, whereas 1 sustained stroke after discharge). Receiver operating characteristic curve analysis was performed to determine the optimal cut-off levels of 4 LA functional indices: LA emptying fraction (LAEmpF), LA longitudinal strain (LALS), LA circumferential strain (LACS), and LA area change ratio (LAAC), using 3DSTE. Among these factors, 2DLVLS, 3DLAEmpF, and 3DLALS demonstrated a higher hazard ratio (>5.0) than other variables. The 3DLAEmpF and 3DLALS had a higher average treatment effect (ATE) and ATE on the treated (ATT), respectively, than the other indices after propensity score matching. Addition of 3DLAEmpF to the base model using clinical variables and LV ejection fraction or 2DLVLS demonstrated higher prognostic power.

CONCLUSIONS

LAEmpF calculated using 3DSTE possessed additive prognostic values for the prediction of MACE.

Novel Approaches in Cardiac Imaging for Non-invasive Assessment of Left Heart Myocardial Fibrosis

In the past, the identification of myocardial fibrosis was only possible through invasive histologic assessment. Although endomyocardial biopsy remains the gold standard, recent advances in cardiac imaging techniques have enabled non-invasive tissue characterization of the myocardium, which has also provided valuable insights into specific disease processes. The diagnostic accuracy, incremental yield and prognostic value of speckle tracking echocardiography, late gadolinium enhancement and parametric mapping modules by cardiac magnetic resonance and cardiac computed tomography have been validated against tissue samples and tested in broad patient populations, overall providing relevant clinical information to the cardiologist. This review describes the patterns of left ventricular and left atrial fibrosis, and their characterization by advanced echocardiography, cardiac magnetic resonance and cardiac computed tomography, allowing for clinical applications in sudden cardiac death and management of atrial fibrillation.

Assessment of right atrial dyssynchrony by 2D speckle-tracking in healthy young men following high altitude exposure at 4100 m

Background

High altitude exposure induces overload of right-sided heart and may further predispose to supraventricular arrhythmia. It has been reported that atrial mechanical dyssynchrony is associated with atrial arrhythmia. Whether high altitude exposure causes higher right atrial (RA) dyssynchrony is still unknown. The aim of study was to investigate the effect of high altitude exposure on right atrial mechanical synchrony.

Methods

In this study, 98 healthy young men underwent clinical examination and echocardiography at sea level (400 m) and high altitude (4100 m) after an ascent within 7 days. RA dyssynchrony was defined as inhomogeneous timing to peak strain and strain rate using 2D speckle-tracking echocardiography.

Results

Following high altitude exposure, standard deviation of the time to peak strain (SD-TPS) [36.2 (24.5, 48.6) ms vs. 21.7 (12.9, 32.1) ms, p<0.001] and SD-TPS as percentage of R–R’ interval (4.6 ± 2.1% vs. 2.5 ± 1.8%, p<0.001) significantly increased. Additionally, subjects with higher SD-TPS (%) at high altitude presented decreased right ventricular global longitudinal strain and RA active emptying fraction, but increased RA minimal volume index, which were not observed in lower group. Multivariable analysis showed that mean pulmonary arterial pressure and tricuspid E/A were independently associated with SD-TPS (%) at high altitude.

Conclusion

Our data for the first time demonstrated that high altitude exposure causes RA dyssynchrony in healthy young men, which may be secondary to increased pulmonary arterial pressure. In addition, subjects with higher RA dyssynchrony presented worse RA contractile function and right ventricular performance.

The prognostic value of left atrial dyssynchrony measured by speckle tracking echocardiography in the general population

LA dyssynchrony is a predictor of cardiovascular morbidity in various patient populations. However, the prognostic value of LA dyssynchrony as evaluated by two-dimensional speckle tracking (2D-STE) in the general population is unknown. A cohort of 375 participants without atrial fibrillation (AF), ischemic heart disease (IHD), heart failure (HF) or previous ischemic stroke (IS) had an echocardiogram, including LA 2D-STE, performed. LA dyssynchrony was defined as the standard deviation of the time to peak regional LA reservoir strain values. The endpoints were all-cause mortality, a combined endpoint of AF and IS, and a combined endpoint of major adverse cardiovascular events (MACE) comprised of acute myocardial infarction (AMI), HF or cardiovascular death (CVD). During a median follow up of 16.1 years (IQR 15.0-16.3 years), 83 (22%) participants died, 60 (15%) reached the composite endpoint of AF and IS, and 38 (10%) reached the composite MACE endpoint. LA dyssynchrony was a univariable predictor of all-cause mortality (HR 1.07, 95% CI 1.02-1.11, p = 0.001) but was not significantly associated with the combined endpoint of AF and IS (HR 1.05, p = 0.064) nor MACE (HR 1.04, p = 0.22). However, when adjusted for age, LA dyssynchrony did not predict all-cause mortality (HR 1.03, p = 0.28). Similarly, after further adjustments for clinical and echocardiographic parameters LA dyssynchrony did not predict any of the study outcomes. In this general population study, LA dyssynchrony was not an independent predictor of all-cause mortality and did not predict MACE nor a composite outcome consisting of AF and IS.

A Novel Approach for Predicting Atrial Fibrillation Recurrence After Ablation Using Deep Convolutional Neural Networks by Assessing Left Atrial Curved M-Mode Speckle-Tracking Images

Aims: Curved M-mode images of global strain (GS) and strain rate (GSR) provide sufficiently detailed spatiotemporal information of deformation mechanics. This study investigated whether a deep convolutional neural network (CNN) could accurately classify these images in patients with atrial fibrillation (AF) who underwent radiofrequency catheter ablation (RFCA) with different outcomes.

Methods and Results: We retrospectively evaluated 606 consecutive patients who underwent RFCA for drug-refractory AF. Patients were divided into AF-free (n = 443) and AF-recurrent (n = 163) groups. Transthoracic echocardiography was performed within 24 h after RFCA. Left atrial curved M-mode speckle-tracking images were acquired from randomly selected 163 patients in AF-free group and 163 patients in AF-recurrent group as the dataset for deep CNN modeling. We used the ReLu activation function and repeatedly performed CNN model for 32 times to evaluate the stability of hyperparameters. Logistic regression models with the left atrial dimension, emptying fraction, and peak systolic GS as predictor variables were used for comparisons. Images from the apical 2-chamber (2-C) and 4-chamber (4-C) views had distinct features, leading to different CNN performance between settings; of them, the “4-C GS+4-C GSR” setting provided the highest performance index values. All four predictor variables used for logistic regression modeling were significant; however, none of them, individually or in any combined form, could outperform the optimal CNN model.

Conclusion: The novel approach using deep CNNs for learning features of left atrial curved M-mode speckle-tracking images seems to be optimal for classifying outcome status after AF ablation.

Assessment of atrial function by myocardial deformation techniques in hypertrophic cardiomyopathy

BACKGROUND

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

AIMS

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

METHODS

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

RESULTS

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

CONCLUSION

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

Atrial Dyssynchrony Measured by Strain Echocardiography as a Marker of Proarrhythmic Remodeling and Oxidative Stress in Cardiac Surgery Patients

Aging leads to structural and electrophysiological changes that increase the risk of postoperative atrial arrhythmias; however, noninvasive preoperative markers of atrial proarrhythmic conditions are still needed. This study is aimed at assessing whether interatrial dyssynchrony determined using two-dimensional speckle tracking echocardiography relates to proarrhythmic structural and functional remodeling. A cohort of 45 patients in sinus rhythm referred for cardiac surgery was evaluated by echocardiography and surface electrocardiogram the day before the intervention. Transmembrane potential, connexin, and potassium channel distribution, inflammatory, and nitrooxidative markers were measured from right atrial tissue obtained from patients. A difference greater than 40 milliseconds between right and left atrial free wall contraction confirmed the presence of interatrial dyssynchrony in 21 patients. No difference in relation with age, previous diseases, and 2-dimensional echocardiographic findings as well as average values of global longitudinal right and left atrial strain were found between synchronic and dyssynchronic patients. Postoperative atrial fibrillation incidence increased from 8.3% in the synchronic group to 33.3% in the dyssynchronic ones. P wave duration showed no difference between groups. Action potentials from dyssynchronous patients decreased in amplitude, maximal rate of depolarization, and hyperpolarized. Duration at 30% of repolarization increased, being markedly shorter at 90% of repolarization. Only the dyssynchronous group showed early and delayed afterdepolarizations. Atrial tissue of dyssynchronous patients displayed lateralization of connexin 40 and increased connexin 43 expression and accumulation of tumor necrosis factor-α in the intercalated disc. Tumor necrosis factor-α did not colocalize, however, with lateralized connexin 40. Nitroxidative marks and KATP channels increased perivascularly and in myocytes. Our results demonstrate that, as compared to a traditional surface electrocardiogram, the novel noninvasive echocardiographic evaluation of interatrial dyssynchrony provides a better identification of nonaged-related proarrhythmic atrial remodeling with increased susceptibility to postoperative atrial fibrillation.

Left atrial wall dyskinesia assessed during contractile phase as a predictor of atrial fibrillation recurrence after electrical cardioversion performed due to persistent atrial fibrillation

Direct current cardioversion (DCCV) is one of the basic methods for restoring sinus rhythm (SR) in patients with atrial fibrillation (AF). Left atrial (LA) strain is one of the parameters used to assess the risk of AF recurrence following DCCV. Assessing the strain also allows for the detection of segmental disorders of LA wall contractility, including dispersion or dyskinesia. In the present study, we determined the predictive value of LA wall dyskinesia in assessing the risk of AF recurrence after DCCV. We performed a comprehensive echocardiography in 89 patients with persistent AF following successful DCCV. We assessed the strain and strain rate in the reservoir (r), conduit, and contractile (ct) phases by using speckle tracking echocardiography. Dyskinesia was diagnosed when the strain rate of any segment of the LA wall displayed positive values during contraction. After 12 months, 47.2% of patients maintained SR. Patients who maintained SR had a significantly lower LA strain (LAS)r assessed in the apical 4-chamber view (4c) (11.38 ± 4.63 vs 14.54 ± 5.11; P = .004) and 2-chamber view (2c) (11.05 ± 4.1 vs 14.93 ± 6.82%; P = .006), LASct4c (2.51 ± 2.3 vs 5.09 ± 3.29%; P < .001), LASct2c (3.6 ± 2.98 vs 5.67 ± 4.23%; P = .008), peak strain rate (pLASR) ct4c (0.36 ± 0.24 s vs 0.62 ± 0.4; P < .001) and pLASRct2c (0.49 ± 0.30 vs 0.79 ± 0.53 s; P = .01). LA dyskinesia was observed less frequently in the 4c view in patients who maintained SR (59.57 vs 17.5%; P < .001). Multivariable logistic regression showed that the LASct4c (odds ratio (OR) 0.78; 95%CI 0.63-0.97; P = .027) and LA dyskinesia observed in the 4c view (OR 3.53; 95%CI 1.16-10.76; P = .027) were significant independent predictors of AF recurrence at 12 months. We conclude that LA dyskinesia observed in the 4c view and LASct4c are independent risk factors for AF recurrence following DCCV.

Long-Term Left Atrial Function after Device Closure and Surgical Closure in Adult Patients with Atrial Septal Defect

BACKGROUND

Studies comparing left atrial (LA) function after surgical closure or percutaneous closure in patients with an atrial septal defect (ASD) are lacking.

METHODS

Between 1 and 3 years after ASD treatment, we retrospectively analyzed the medical records and transthoracic echocardiographic images of patients who had been diagnosed with an ASD after 20 years of age and who had undergone surgical closure (ASD-S) or percutaneous device closure (ASD-D). We measured LA peak systolic, early diastolic, and late diastolic strain values using 2-dimensional (2D) speckle tracking echocardiography (STE) and calculated reservoir, conduit, and contraction strain.

RESULTS

The reservoir strain value of the ASD-D groups was 25.2% ± 7.4%, which was lower compared to the control group (33.6% ± 5.5%) (p = 0.004). The LA conduit strain and the LA contraction values of the ASD-D group were also lower compared to the control group (−13.8% ± 5.8% vs. −20.4% ± 4.7%, p = 0.034; −11.3% ± 4.2% vs. −13.2% ± 2.5%, p = 0.037, respectively). The reservoir, conduit, and contraction strains of the ASD-S group were 27.8% ± 8.8%, −15.3% ± 6.4%, and −12.5% ± 5.8%, respectively, and were not different from those of the control group or the ASD-D group.

CONCLUSIONS

The 2D STE is a suitable method for evaluating LA function after ASD closure. Our results demonstrate that 1 year after device closure, the LA reservoir, conduit and contraction function were reduced in ASD-D group compared to healthy controls, while there was no difference between the ASD-S and ASD-D groups.

Determinants of LA reservoir strain: Independent effects of LA volume and LV global longitudinal strain

BACKGROUND

Left atrial (LA) deformation during the reservoir phase (LASr) has demonstrated strong prognostic value in different clinical settings. Although determinants of left atrial reservoir strain including left atrial relaxation, left atrial compliance, and left ventricular longitudinal systolic function are fairly well defined, there is incomplete information regarding the effect of left atrial volume on this relationship which is the focus of our study.

METHOD

Consecutive patients without prior cardiac disease referred for transthoracic echocardiography were prospectively recruited. All participants underwent clinical assessment, transthoracic echocardiography (TTE), and screening exercise stress test. Only patients with normal left ventricular ejection fraction (LVEF) without left ventricular hypertrophy (LVH) or myocardial ischemia on stress testing were included.

RESULTS

A total of 260 patients (57% male, mean age 59 ± 14 years) were included. 70% had hypertension, 33% had diabetes mellitus, and 31% had both HTN and DM. On multivariate analysis, age, e', LAVI, and LV GLS (P < .01 for all) showed an independent association with LASr. Of interest, at lower tertiles of LAVI, a linear decrease in LASr was observed parallel to worsening LV GLS, whilst at higher tertiles of LAVI, the reduction in LASr was non-linear implying that LA enlargement, consequent to LA remodeling, had an incremental effect on LASr.

CONCLUSION

Age, e', LV GLS, and LAVI were independently associated with LASr. LA remodeling reflected by larger LAVI had an incremental negative association with LASr independent of LV GLS.

Association between Left Atrial Deformation and Brain Involvement in Patients with Anderson-Fabry Disease at Diagnosis

Background: Anderson-Fabry disease (AFD) can induce both central nervous system white matter lesions (WMLs) and cardiac abnormalities including left atrial (LA) dysfunction. We sought to evaluate the possible interrelations of LA structure and function impairment with the presence of WMLs in AFD patients. Methods 22 AFD patients and 22 controls, matched for age and sex, underwent an echo-Doppler exam including quantification of peak atrial longitudinal strain (PALS). AFD patients underwent also a 3-T brain magnetic resonance imaging with a visual quantification of WMLs by Fazekas’ score (FS) on 3D FLAIR images. Results AFD patients had significantly higher left ventricular (LV) mass index (LVMi) and relative wall thickness, and lower PALS compared to controls. Among AFD patients, 9 showed a FS = 0, and 13 a FS > 1. AFD patients with FS ≥ 1 showed lower PALS (29.4 ± 6.7 vs. 37.2 ± 3.9%, p = 0.003) than those with FS = 0, without difference in LA volume index and LVMi. In AFD patients, FS was inversely related to PALS (r = −0.49, p < 0.0001), even after adjusting for LVMi (r = −0.43, p < 0.05). Conclusions In the absence of significant alterations in LA size, AFD patients had lower PALS compared to controls. The inverse association between PALS and presence of WMLs indicates a possible parallel early involvement of heart and brain.

Usefulness of left atrial speckle tracking echocardiography in predicting recurrence of atrial fibrillation after radiofrequency ablation: a systematic review and meta-analysis

The usefulness of peak atrial longitudinal strain (PALS) in identifying patients at high risk of atrial fibrillation (AF) recurrence after radiofrequency ablation (RFA) has been investigated in several small AF populations. The aim of this systematic review and meta-analysis was to investigate whether PALS predicts recurrence of AF after RFA treatment. MEDLINE, EMBASE and the Cochrane Library were searched. Studies investigating the value of PALS in predicting successful RFA in AF patients were selected. Patients underwent echocardiography prior to RFA. Risk of bias was evaluated using the Quality in Prognosis Studies (QUIPS) Tool. Twelve studies and a total of 1025 patients suffering from paroxysmal or persistent AF were included. Odds ratios (OR) were assessed in a random and fixed effects model for univariable and multivariable pooled analyses respectively. PALS was found to be a significant predictor of AF recurrence after RFA across study populations (Univariable: OR: 1.17, CI95% [1.03-1.34], p = 0.018, per 1% decrease) (Multivariable: OR: 1.16, CI95% [1.09-1.24], p < 0.001, per 1% decrease). Patients with recurrence had significantly lower PALS prior to RFA than patients who maintained sinus rhythm (15.7 ± 5.7% vs. 23.0 ± 7.0%, p = 0.016). A pooled analysis of weighted mean differences (WMD) also showed a significant difference in PALS between the two groups (WMD: - 6.57, CI95% [- 8.49: - 4.65], p < 0.001). Lower values of PALS are associated with an increased risk of AF recurrence after RFA. PALS provides prognostic value in clinical practice.