Empagliflozin and left atrial function in patients with type 2 diabetes mellitus and coronary artery disease: insight from the EMPA-HEART CardioLink-6 randomized clinical trial.

BACKGROUND: Sodium-glucose cotransporter-2 (SGLT2) inhibitors have demonstrated reduction in heart failure outcomes in patients with type 2 diabetes mellitus, although the exact mechanism of benefit remains unclear. Alteration in left atrial (LA) function due to chronic pressure or volume overload is a hallmark of heart failure. OBJECTIVE: To evaluate the effect of the SGLT2 inhibitor empagliflozin on LA volume and function. METHODS: 90 patients with coronary artery disease and type 2 diabetes (T2DM) were randomized to empagliflozin (n = 44) or placebo (n = 46), and underwent cardiac magnetic resonance (CMR) imaging at baseline and after 6 months. The main outcome was change in LA volume; LA function, including active and passive components, was also measured by a blinded reader. RESULTS: At baseline, there was no significant difference in LA volumes between the empagliflozin (indexed maximum LA volume 26.4 ± 8.4mL/m2, minimum LA volume 11.1 ± 5.7mL/m2) and placebo (indexed maximum LA volume 28.7 ± 8.2mL/m2, minimum LA volume 12.6 ± 5.0mL/m2) groups. After 6 months, changes in LA volumes did not differ with adjusted difference (empagliflozin minus placebo): 0.99 mL/m2 (95% CI: -1.7 to 3.7 mL/m2; p = 0.47) for indexed maximum LA volume, and 0.87 mL/m2 (95% CI: -0.9 to 2.6 mL/m2; p = 0.32) for indexed minimum LA volume. Changes in total LA emptying fraction were also similar, with between-group adjusted mean difference - 0.01 (95% CI: -0.05 to 0.03, p = 0.59). CONCLUSION: SGLT2 inhibition with empagliflozin for 6 months did not have a significant impact on LA volume and function in patients with T2DM and coronary artery disease. (Effects of Empagliflozin on Cardiac Structure in Patients with Type 2 Diabetes [EMPA-HEART]; NCT02998970).

Impacts of Left Atrial Appendage Treatments on Mitral Valve Diseases during Surgical Ablations.

Background: Left atrial appendages (LAAs) play an important role in regulating left atrial function, and much evidence supports the possibility that changes in left atrial structure may cause or worsen mitral regurgitation. This study intended to investigate the outcomes of patients with mitral regurgitation who underwent left atrial appendage closure (resection or endocardial closure) during isolated surgical ablations. Methods: Patients with mild or moderate mitral regurgitation who received isolated surgical ablations for atrial fibrillation (AF) in our center from 2013 to 2022 were referred. During follow-up, each clinical visit was composed of medical interrogation, a 24 h Holter, and echocardiographic evaluation. Death, atrial fibrillation, worsening of mitral regurgitation, and stroke were evaluated as outcomes. Freedom from outcomes whose results were adjusted by inverse probability of treatment weighting for causal effects after acquiring propensity scores. Results: A total of 456 patients were enrolled in this study. During a median follow-up of 48 months, 30 deaths and 11 cases of stroke were observed. After adjustments, no significant differences in terms of death or stroke were observed among the three groups. Patients who underwent resection or endocardial closure during surgical ablations had a higher risk of mitral regurgitation worsening during follow-up (p < 0.05). During the whole follow-up, patients who underwent left atrial appendage interventions showed significantly larger left atrial and mitral annular diameters, as well as lower tethering height than those who had left atrial appendage preserved (all p < 0.05). Conclusions: Mitral regurgitation was more likely to get worse when patients with fundamental mitral diseases underwent LAA interventions during isolated surgical AF ablations. In the absence of LAA, the dilation of the left atrium and mitral annulus may ultimately lead to worsening of regurgitation.

Age- and Sex-Specific MR-Feature Tracking Reference Values of Right Atrial Deformation in Healthy Adults.

BACKGROUND: Although right atrial (RA) myocardial deformation has important implications for patient diagnosis, prognosis, and risk stratification, its implementation in clinical practice has been hampered by limited normal reference values, especially in Asian populations. PURPOSE: To establish age- and sex-specific reference values for RA strain, strain rate (SR), and displacement based on a large sample of healthy Chinese adults using MR-feature tracking (MR-FT). STUDY TYPE: Retrospective. POPULATION: 524 healthy Chinese adults (287 male; mean age 43.7 ± 11.9 years). FIELD STRENGTH/SEQUENCE: 1.5T/balanced steady-state free precession. ASSESSMENT: RA deformation parameters, including reservoir, conduit, and booster strain (εs, εe, and εa), peak positive, early negative, and late negative SR (SRs, SRe, and SRa), and total, passive, and active displacement (Ds, De, and Da), were assessed using MR-FT. STATISTICAL TESTS: Student's t-test, one-way ANOVA, coefficients of determination (r2 ), intraclass correlation coefficients (ICC), and Bland-Altman plots. A P value <0.05 was considered significant. RESULTS: Women demonstrated significantly greater magnitudes of RA deformation parameters than men: εs (57.4% ± 15.1% vs. 44.3% ± 12.6%), εe (37.5% ± 13.4% vs. 27.4% ± 10.9%), εa (19.9% ± 5.7% vs. 16.9% ± 5.0%), SRs (2.62 ± 0.88 sec-1 vs. 2.00 ± 0.63 sec-1 ), SRe (-2.98 ± 1.26 sec-1 vs. -2.16 ± 0.92 sec-1 ), SRa (-2.28 ± 0.75 sec-1 vs. -1.84 ± 0.62 sec-1 ), Ds (-7.80 ± 1.90 mm vs. -7.46 ± 1.70 mm), and De (-4.84 ± 1.31 mm vs. -4.49 ± 1.21 mm). For both sexes, aging was significantly associated with decreased RA reservoir and conduit function (εs, SRs, Ds, εe, SRe, and De), and with increased εa and Da. RA deformation measurements had good to excellent intraobserver and interobserver reproducibility, with ICCs ranging from to 0.790 to 0.972. DATA CONCLUSION: This study provides age- and sex-specific reference values of RA strain, SR, and displacement based on a large cohort of healthy Chinese adults using MR-FT. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.

Investigation of left atrial mechanical function and left ventricular systolic and diastolic parameters in athletes performing resistance exercise and combined exercise.

Some individuals who go to fitness centers for various purposes perform resistance exercise (RE) alone, while others engage in combined exercise (CE) by including cardio exercises along with RE. Studying the effects of these two different training methods on left ventricular (LV) systolic and diastolic parameters and left atrial mechanical function is an important step toward understanding the effects of different types of exercise on cardiac function. This knowledge has significant implications for public health, as it can inform the development of targeted and effective exercise programs that prioritize cardiovascular health and reduce the risk of adverse outcomes. Therefore, the primary aim of this study is to comprehensively investigate the LV systolic and diastolic parameters of athletes who engage in RE and CE using ECHO, to contribute to the growing body of literature on the cardiovascular effects of different types of exercise. Forty-two amateur athletes aged between 17 and 52 were included in our study. The participants consisted of the RE (n = 26) group who did only resistance exercise during the weekly exercise period, and the CE group (n = 16) who also did cardio exercise with resistance exercises. After determining sports age (year), weekly exercise frequency (day), and training volume (min) in addition to demographic information of RE and CE groups, left ventricular systolic and diastolic parameters and left atrial functions were determined by ECHO. Findings from our study revealed that parameters including the left ventricular end-diastolic diameter (LVEDD) (p = .008), left ventricular end-diastolic volume (LVEDV) (p = .020), stroke volume index (SV-I) (p = .048), conduit volume (CV-I) (p = .001), and aortic strain (AS) (p = .017) were notably higher in the RE group compared to the CE group. Also left atrial active emptying volüme (LAAEV) of CE was higher than the RE group (p = .031). In conclusion, the cardiac parameters of the RE group showed more athlete's heart characteristics than the CE group. These results may help to optimize the cardiovascular benefits of exercise routines while minimizing the potential risks associated with improper training.

Effect of tafamidis on left atrial function of patients with transthyretin amyloid cardiomyopathy.

Transthyretin amyloid cardiomyopathy (ATTR-CM) is characterized by the functional and structural effects of amyloid infiltration, predominantly within the ventricles, causing biventricular wall thickening. Amyloid infiltration can be observed in the left atrium in ATTR-CM patients, but the association of left atrial (LA) myocardial function with cardiovascular events and of changes in LA myocardial function with tafamidis administration have not yet been clarified. Our aim was, therefore, to use speckle-tracking strain for investigating LA myocardial function in patients with ATTR-CM treated with tafamidis. We studied 55 patients with biopsy-proven ATTR-CM who had been treated with tafamidis (age: 76 ± 2 years, male: 93%). For speckle-tracking analysis of LA myocardial function, the systolic LA strain (LA reservoir function) was defined for this study as LA myocardial function from the apical 4-chamber view. The primary endpoint was defined as a composite comprising cardiovascular death and/or heart failure hospitalization after tafamidis administration over a median follow-up period of 28 ± 4 months. Patients with baseline LA strain < 8.6% (median value) experienced significantly more cardiovascular events than those without (log-rank P = 0.002). Moreover, LA strain in 26 patients worsened after tafamidis administration, and multivariate logistic regression analysis showed age, global longitudinal strain and relative apical longitudinal strain index were identified as independent determinants of deterioration of LA strain after tafamidis administration. In conclusion, baseline LA reservoir function is closely associated with cardiovascular events after tafamidis administration, and could be an additional parameter for the management of patients with ATTR-CM.

Prognostic value of right atrial strain in systemic sclerosis based on tissue tracking analysis using cine cardiac magnetic resonance imaging: a retrospective observational study.

Interstitial lung disease and cardiac involvement are common manifestations and prognostic factors of systemic sclerosis. However, it is unclear whether impaired right atrial function associated with interstitial lung disease in systemic sclerosis can be used as a prognostic factor in this patient population. Therefore, this study aimed to investigate the relationship between right atrial function, interstitial lung disease, and prognosis in patients with systemic sclerosis using tissue tracking analysis with cine cardiac magnetic resonance imaging. In this retrospective observational study, a total of 40 patients with systemic sclerosis were enrolled. Tissue tracking analysis was used to obtain time curves of right atrial strain. Reservoir (total strain), conduit (passive strain), and booster (active strain) pump function were calculated, and right atrial strain, interstitial lung disease, and clinical outcomes were examined. An adverse clinical event was defined as all-cause death. Overall, 23 patients had interstitial lung disease (58%). Six patients died during the follow-up (median, 44 months). The total skin score and right ventricular systolic pressure on echocardiography were higher in patients with an event than in those without an event (28 ± 16% vs. 13 ± 13%, P = 0.02; 46.3 ± 10.7 mmHg vs. 36.0 ± 8.5 mmHg, P = 0.01, respectively). Further, right atrial total strain and active strain were significantly lower in patients with an event than in those without an event (14.3 ± 11.3% vs. 25.8 ± 11.4%, P = 0.03; 3.48 ± 2.37 vs. 11.7 ± 6.78, P = 0.007, respectively). Multivariate analysis revealed that active strain was an independent predictor of all-cause death (hazard ratio 0.76, P = 0.029). Kaplan-Meier analysis revealed that the survival rate was significantly higher in patients with right atrial active strain levels above the cutoff 7.4 (P < 0.05). In systemic sclerosis, right atrial booster function was predictive of mortality. Hence, right atrial functional assessment may have incremental prognostic value for patients with systemic sclerosis, leading to better risk stratification.

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 ß-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 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.

Atrial Pacing Negatively Affects Left Atrial Morphological and Functional Parameters Similarly to Atrioventricular Dyssynchrony.

Background and Objectives: Atrioventricular (AV) dyssynchrony as well as atrial and ventricular pacing affect left atrial (LA) function. We conducted a study evaluating the effect of atrial and ventricular pacing on LA morphological and functional changes after dual-chamber pacemaker implantation. Materials and Methods: The study prospectively enrolled 121 subjects who had a dual-chamber pacemaker implanted due to sinus node disease (SND) or atrioventricular block (AVB). Subjects were divided into three groups based on indication and pacemaker programming: (1) SND DDDR 60; (2) AVB DDD 60 and (3) AVB DDD 40. Subjects were invited to one- and three-month follow-up visits. Three subsets based on pacing burden were analyzed: (1) high atrial (A) low ventricular (V); (2) high A, high V and (3) low A, high V. LA function was assessed from volumetric parameters and measured strains from echocardiography. Results: The high A, low V group consisted of 38 subjects; while high A, high V had 26 and low A, high V had 23. A significant decrease in reservoir and contractile LA strain parameters were only observed in the high A, low V pacing group after three months (reservoir 25.9 ± 10.3% vs. 21.1 ± 9.9%, p = 0.003, contractile -14.0 ± 9.0% vs. -11.1 ± 7.8, p = 0.018). While the re-established atrioventricular synchrony in the low A, high V group maintained reservoir LA strain at the baseline level after three months (21.4 ± 10.4% vs. 22.5 ± 10.4%, p = 0.975); in the high A, high V group, a further trend to decrease was noted (20.3 ± 8.9% vs. 18.7 ± 8.3%, p = 0.231). Conclusions: High atrial pacing burden independently of atrioventricular dyssynchrony and ventricular pacing impairs LA functional and morphological parameters. Changes appear soon after pacemaker implantation and are maintained.

The Clinical Applications of Left Atrial Strain: A Comprehensive Review.

Left atrial (LA) strain imaging, which measures the deformation of the LA using speckle-tracing echocardiography (STE), has emerged recently as an exciting tool to help provide diagnostic and prognostic information for patients with a broad range of cardiovascular (CV) pathologies. Perhaps due to the LA's relatively thin-walled architecture compared with the more muscular structure of the left ventricle (LV), functional changes in the left atrium often precede changes in the LV, making LA strain (LAS) an earlier marker for underlying pathology than many conventional echocardiographic parameters. LAS imaging is typically divided into three phases according to the stage of the cardiac cycle: reservoir strain, which is characterized by LA filling during systole; conduit strain, which describes LA deformation during passive LV filling; and booster strain, which provides information on the LA atrium during LA systole in late ventricular diastole. While additional large-population studies are still needed to further solidify the role of LAS in routine clinical practice, this review will discuss the current evidence of its use in different pathologies and explore the possibilities of its applications in the future.

Effects of Liraglutide, Empagliflozin and Their Combination on Left Atrial Strain and Arterial Function.

Background and Objectives: Glucagon-like peptide-1 receptor agonists (GLP-1RA) and sodium-glucose cotransporter-2 inhibitors (SGLT-2i) are cardioprotective drugs. We investigated their effects on left atrial function, a major determinant of cardiac diastolic dysfunction in type 2 diabetes mellitus. We also explored the association of changes in arterial stiffness with those of the LA strain after treatment. Materials and Methods: A total of 200 patients (59.5 ± 9.1 year old, 151 male) with type 2 diabetes mellitus treated with metformin were randomized to insulin (n = 50 served as controls), liraglutide (n = 50), empagliflozin (n = 50) or their combination (liraglutide + empagliflozin) (n = 50). We measured at baseline and 6 months post-treatment: (a) left atrial and global left ventricular longitudinal strain by speckle tracking echocardiography; (b) pulse wave velocity (PWV) and central systolic blood pressure. Results: At baseline, there was a correlation of the LA reservoir strain with PWV (r = -0.209, p = 0.008), central SBP (r = -0.151, p = 0.030), EF (r = 0.214, p = 0.004) and GLS (r = -0.279, p = 0.009). The LA reservoir change 6 months post-treatment was correlated with the PWV change in all groups (r = -0.242, p = 0.028). The LA reservoir change 6 months post-treatment was correlated with the GLS change in all groups (r = -0.322, p = 0.004). Six months after intervention, patients treated with liraglutide, empagliflozin and their combination improved the left atrial reservoir strain (GLP1RA 30.7 ± 9.3 vs. 33.9 ± 9.7%, p = 0.011, SGLT2i 30 ± 8.3 vs. 32.3 ± 7.3%, p = 0.04, GLP1&SGLT2i 29.1 ± 8.7 vs. 31.3 ± 8.2, p = 0.007) compared to those treated with insulin (33 ± 8.3% vs. 32.8 ± 7.4, p = 0.829). Also, patients treated with liraglutide and the combination liraglutide and empagliflozin had improved left atrial conduction strain (p < 0.05). Empagliflozin or the combination liraglutide and empagliflozin showed a greater decrease of PWV and central and brachial systolic blood pressure than insulin or GLP-1RA. (p < 0.05). Conclusions: Impaired aortic elastic properties are associated with a decreased LA strain in type 2 diabetics. Treatment with liraglutide, empagliflozin and their combination for 6 months showed a greater improvement of left atrial function compared to insulin treatment in parallel with the improvement of arterial and myocardial functions.

Ablation of atrial fibrillation beyond pulmonary vein isolation: Do additional ablation lesions impact left atrial function?

INTRODUCTION: Electrical isolation of pulmonary veins (PVI) is a cornerstone for atrial fibrillation (AF) ablation. The overall effect of AF ablation, and especially lesions beyond PVI, on left atrial (LA) function is currently poorly understood. Our aim was to determine if LA function is different in patients after extensive LA ablation compared to PVI only. We performed non-inferiority analysis of LA function after PVI with additional nonpulmonary vein ablation lesions in LA (PVI+) and PVI alone. METHODS: We studied 68 patients consecutive patients who underwent AF ablation and who had complete transthoracic echocardiogram (TTE) within 12 months before AF ablation and 1-12 months after the procedure. Patients were stratified into two groups: PVI only and PVI+. Primary outcome was change in LA reservoir strain (LASr). Noninferiority margin was defined at 6%. RESULTS: The PVI only group had a higher proportion of patients with paroxysmal AF (70% vs. 30%). The PVI+ group was observed to have a slightly higher increase in LASr compared to PVI alone (5.0% vs. 4.3%, p < .01 for noninferiority). LASr noninferiority was confirmed when adjusted for age, sex, coronary artery disease, hyperlipidemia, and AF type, rhythm at preprocedure TTE in a multivariable linear regression model, 90% CI (-5.46 to 2.04), p < .01. CONCLUSION: LA functional improvement evaluated by LASr was noninferior after PVI with additional LA ablation lesions compared to PVI alone. These findings were confirmed when adjusted for confounding clinical variables, suggesting that more extensive ablation does not negatively affect LA function.

Ventricular-atrial coupling in subjects with normal, preserved, and reduced left ventricular ejection fraction: insights from cardiac magnetic resonance imaging.

OBJECTIVES: To assess the correlation between LA and LV strain measurements in different clinical scenarios and evaluate to what extent LA deformation contributes to the prognosis of patients. METHODS: A total of 297 consecutive participants including 75 healthy individuals, 75 hypertrophic cardiomyopathy (HCM) patients, 74 idiopathic dilated cardiomyopathy (DCM), and 73 chronic myocardial infarction (MI) patients were retrospectively enrolled in this study. The associations of LA-LV coupling with clinical status were statistically analyzed by correlation, multiple linear regression, and logistic regression. Survival estimates were calculated by receiver operating characteristic analyses and Cox regression analyses. RESULTS: Overall, moderate correlations were found between LA and LV strain in every phase of the cardiac cycle (r: -0.598 to -0.580, all p < 0.001). The slope of the regression line of the individual strain-strain curve had a significant difference among 4 groups (-1.4 ± 0.3 in controls, -1.1 ± 0.6 in HCM, -1.8 ± 0.8 in idiopathic DCM, -2.4 ± 1.1 in chronic MI, all p < 0.05). During a median follow-up of 4.7 years, the total LA emptying fraction was independently associated with primary (hazard ratio: 0.968, 95% CI: 0.951-0.985) and secondary endpoints (hazard ratio: 0.957, 95% CI: 0.930-0.985) with an area under the curve (AUC) of 0.720 respectively, 0.806, which was significantly higher than the AUC of LV parameters. CONCLUSIONS: The coupled correlations between the left atria and ventricle in every phase and the individual strain-strain curve vary with etiology. LA deformation in late diastole provides prior and incremental information on cardiac dysfunction based on LV metrics. The total LA emptying fraction was an independent indicator for clinical outcome superior to that of LV typical predictors. CLINICAL RELEVANCE STATEMENT: Left ventricular-atrial coupling is not only valuable for comprehending the pathophysiological mechanisms of cardiovascular diseases caused by different etiologies but also holds significant importance for the prevention of adverse cardiovascular events and targeted treatment. KEY POINTS: • In HCM patients with preserved LVEF, LA deformation is a sensitive indicator for cardiac dysfunction prior to LV parameters with a reduced LA/LV strain ratio. • In patients with reduced LVEF, LV deformation impairment is more consequential than that of the LA with an increased LA/LV strain ratio. Furthermore, impaired LA active strain indicates potential atrial myopathy. • Among LA and LV parameters, the total LA emptying fraction is the best predictor for guiding clinical management and follow-up in patients with different statuses of LVEF.

Analysis of bi-atrial function using CMR feature tracking and long-axis shortening approaches in patients with diastolic dysfunction and atrial fibrillation.

OBJECTIVES: Atrial function can be assessed using advancing cardiovascular magnetic resonance (CMR) post-processing methods: atrial feature tracking (FT) strain analysis or a long-axis shortening (LAS) technique. This study aimed to first compare the two FT and LAS techniques in healthy individuals and cardiovascular patients and then investigated how left (LA) and right atrial (RA) measurements are related to the severity of diastolic dysfunction or atrial fibrillation. METHODS: Sixty healthy controls and 90 cardiovascular disease patients with coronary artery disease, heart failure, or atrial fibrillation, underwent CMR. LA and RA were analyzed for standard volumetry as well as for myocardial deformation using FT and LAS for the different functional phases (reservoir, conduit, booster). Additionally, ventricular shortening and valve excursion measurements were assessed with the LAS module. RESULTS: The measurements for each of the LA and RA phases were correlated (p < 0.05) between the two approaches, with the highest correlation coefficients occurring in the reservoir phase (LA: r = 0.83, p < 0.01, RA: r = 0.66, p < 0.01). Both methods demonstrated reduced LA (FT: 26 ± 13% vs 48 ± 12%, LAS: 25 ± 11% vs 42 ± 8%, p < 0.01) and RA reservoir function (FT: 28 ± 15% vs 42 ± 15%, LAS: 27 ± 12% vs 42 ± 10%, p < 0.01) in patients compared to controls. Atrial LAS and FT decreased with diastolic dysfunction and atrial fibrillation. This mirrored ventricular dysfunction measurements. CONCLUSION: Similar results were generated for bi-atrial function measurements between two CMR post-processing approaches of FT and LAS. Moreover, these methods allowed for the assessment of incremental deterioration of LA and RA function with increasing left ventricular diastolic dysfunction and atrial fibrillation. A CMR-based analysis of bi-atrial strain or shortening discriminates patients with early-stage diastolic dysfunction prior to the presence of compromised atrial and ventricular ejection fractions that occur with late-stage diastolic dysfunction and atrial fibrillation. KEY POINTS: • Assessing right and left atrial function with CMR feature tracking or long-axis shortening techniques yields similar measurements and could potentially be used interchangeably based on the software capabilities of individual sites. • Atrial deformation and/or long-axis shortening allow for early detection of subtle atrial myopathy in diastolic dysfunction, even when atrial enlargement is not yet apparent. • Using a CMR-based analysis to understand the individual atrial-ventricular interaction in addition to tissue characteristics allows for a comprehensive interrogation of all four heart chambers. In patients, this could add clinically meaningful information and potentially allow for optimal therapies to be chosen to better target the dysfunction.

Prevalence of glucose metabolism disorders and its association with left atrial remodelling before and after catheter ablation in patients with atrial fibrillation.

AIMS: To investigate the exact prevalence of glucose metabolism disorders, and their impact on left atrial (LA) remodelling and reversibility in patients with atrial fibrillation (AF). METHODS AND RESULTS: We examined 204 consecutive patients with AF who underwent their first catheter ablation (CA). Oral glucose tolerance test was used to evaluate glucose metabolism disorders in 157 patients without known diabetes mellitus (DM). Echocardiography was performed before and 6 months after CA. Oral glucose tolerance test identified abnormal glucose metabolism in 86 patients [11 with newly diagnosed DM, 74 with impaired glucose tolerance (IGT) and 1 with impaired fasting glucose (IFG)]. Ultimately, 65.2% of patients had abnormal glucose metabolism. Diabetes mellitus group had the worst LA reservoir strain and LA stiffness (both P < 0.05), while there was no significant difference in baseline LA parameters between normal glucose tolerance (NGT) group and IGT/IFG group. The prevalence of LA reverse remodelling (≥15% decrease in the LA volume index at 6 months after CA) was significantly higher in NGT group compared with IGT/IFG and DM group (64.1 vs. 38.6 vs. 41.5%, P = 0.006). Both DM and IFG/IGT carry a significant risk of lack of LA reverse remodelling independent of baseline LA size and AF recurrence. CONCLUSION: Approximately 65% of patients with AF who underwent their first CA had abnormal glucose metabolism. Patients with DM had significantly impaired LA function compared with non-DM patients. Impaired glucose tolerance/IFG as well as DM carries significant risk of unfavourable LA reverse remodelling. Our observations may provide valuable information regarding the mechanisms and therapeutic strategies of glucose metabolism-related AF.

Analysis of Left Atrial Function after Percutaneous Intramyocardial Septal Radiofrequency Ablation in Hypertrophic Cardiomyopathy.

INTRODUCTION: The main goal of our research was to explore the effect of percutaneous intramyocardial septal radiofrequency ablation (PIMSRA) on left atrial (LA) phasic function in hypertrophic cardiomyopathy (HCM). METHODS: The study included 13 patients who underwent PIMSRA at our hospital. The function of LA including reservoir, conduit, and booster pump was analyzed and compared before and 6 months after PIMSRA in HCM patients. LA reservoir function parameters contain maximal LA volume, minimal LA volume (LAV min), LA ejection fraction (LAEF), LA expansion index (LAEI), and reservoir strain; LA conduit function includes LA volume before atrial systole, LA passive volume, LA passive ejection fraction, and conduit strain; LA booster function involves LA booster volume, LA active ejection fraction, and LA contraction strain. Additionally, 20 healthy controls were selected to compare the LA function of HCM patients. RESULTS: The preoperative LA reservoir and conduit function in HCM patients were significantly impaired compared with the control group, while the change in booster pump function was not obvious. HCM patients at 6 months after PIMSRA had remarkably enhanced reservoir and conduit functions which were manifested by lower LAV min, higher LAEF, LAEI, reservoir, and conduit strain than before the operation, and the differences among these parameters between patients after PIMSRA and the healthy control group were not significant. However, with regard to LA contraction function, there was no significant improvement at 6 months after PIMSRA compared with before operation. CONCLUSION: PIMSRA is effective in the amelioration of LA reservoir and conduit function in patients with HCM but not in a marked improvement of LA contraction function in these individuals in short term.

Echocardiographic Measures of Left Atrial Structure and Function and the Association with Atrial Fibrillation following Acute Coronary Syndrome.

INTRODUCTION: Acute coronary syndrome (ACS) is associated with an increased risk of developing atrial fibrillation (AF). This arrhythmia is associated with adverse outcomes, making it important to identify high-risk patients. The aim was to evaluate the prognostic value of measures of left atrial (LA) structure and function in AF prediction following ACS. METHODS: Three hundred and eighty-one patients who had a percutaneous coronary intervention for ACS were included in the study. Our endpoint was new-onset AF. RESULTS: With a median follow-up time of 5.4 [3.9-6.8] years, 56 patients (14.7%) developed AF. Patients developing AF had significantly (p ≤ 0.05) increased maximal and minimal LA volumes (LAVmax and LAVmin, respectively). LAVmax and LAVmin remained significantly increased in AF patients when indexing to either body surface area (LAVmax/BSA and LAVmin/BSA, respectively), left ventricle length in end diastole (LAVmax/LVLd and LAVmin/LVLd, respectively), or late mitral annular diastolic velocity (LAVmax/a' and LAVmin/a', respectively), while LA expansion index (LAEi), LA emptying fraction (LAEF), and peak LA longitudinal strain (PALS) were decreased. In univariable Cox regressions, all LA measures were found to be predictors of AF. After multivariable adjustment for clinical and echocardiographic parameters, all measures reflecting atrial function (LAVmin, LAVmin/BSA, LAVmin/LVLd, LAVmin/a', LAVmax/a', LAEF, LAEi, and PALS) (p ≤ 0.05) but no structural measures (LAVmax, LAVmax/BSA, and LAVmax/LVLd) remained significant independent predictors of AF. CONCLUSION: Echocardiographic measures of LA function are independent predictors of AF following ACS. Evaluation of LA function might improve the prognostic workup, aid in risk stratification for AF, and improve selection for further examinations.

Diagnostic accuracy of left atrial function and strain for differentiating between acute and chronic myocardial infarction.

BACKGROUND: The cardiac magnetic resonance tissue tracking (CMR-TT) technique was used to obtain left atrial strain and strain rate in patients with myocardial infarction (MI) and to evaluate the utility of this technique in the quantitative assessment of myocardial infarction for distinguishing acute from chronic myocardial infarction. METHODS: We retrospectively analyzed 36 consecutive patients with acute myocardial infarction (AMI) and 29 patients with chronic myocardial infarction (CMI) who underwent CMR and 30 controls. Left atrial (LA) and ventricular functions were quantified by volumetric, and CMR-TT derived strain analysis from long and short left ventricular view cines. Receiver Operating Characteristics (ROC) analysis was used to determine the diagnostic accuracy of CMR-TT strain parameters for discriminating between acute and chronic myocardial infarction. RESULTS: AMI and CMI participants had impaired LA reservoir function, conduit function and LA booster pump dysfunction compared to the controls. LA strain was more sensitive than LV global strain for the assessment of the MI stage. Peak late-negative SR yielded the best areas under the ROC curve (AUC) of 0.879, showing differentiation between acute and chronic myocardial infarction of all the LA strain parameters obtained. The highest significant differences between chronic myocardial infarction and normal myocardium were also found in the LV strain (p < 0.001) and LA functional parameters (p < 0.001), but there was no difference between AMI and normals. CONCLUSIONS: CMR-TT-derived LA strain is a potential and robust tool in demonstrating impaired LA mechanics and quantifying LA dynamics, which have high sensitivity and specificity in the differential diagnosis of acute versus chronic myocardial infarction. Their use is thus worth popularizing in clinical application.

Left atrial functions in the early period after cryoballoon ablation for paroxysmal atrial fibrillation.

PURPOSE: In patients with paroxysmal atrial fibrillation (PAF), functional changes are observed in the left atrium (LA) after pulmonary vein isolation (PVI) procedure. Although previous studies have investigated the altered mechanical functions of the LA with radiofrequency (RF) ablation, changes in the LA functions in the early period after cryoablation (CB-2) have not been clearly demonstrated. This study aims to explore the early periodical changes in mechanical functions of the LA in patients with PAF who underwent CB-2 based ablation through the help of echocardiographic methods which contain Doppler and strain parameters. METHODS: Consecutive 77 patients (mean age: 57.5 ±  11.2; 57% men) with PAF underwent CB-2 were prospectively analyzed. All patients were in sinus rhythm before and after the procedure. The LA dimensions, the LA reservoir strain, the LA atrial contractile strain and the LA conduit strain and left ventricular diastolic function parameters were evaluated by Doppler echocardiography before and 3 months after the procedure. RESULTS: Acute procedural success was achieved in all cases. No major complications were observed. LA reservoir strain and LA contractile strain showed significant recovery after the procedure. (28.3 ± 12.8 vs. 34.6 ± 13.8, p < .001 and -10.8 ± 7.9 vs. -13.9 ± 9.3, p = .014 respectively). No significant change was demonstrated in other echocardiographic parameters. CONCLUSION: Significant improvement in mechanical functions may occur even in the early period after cryoballoon ablation in patients with PAF.

Plasma FGF23 is associated with left atrial remodeling in children on hemodialysis.

BACKGROUND: FGF23 mediates cardiac fibrosis through the activation of pro-fibrotic factors in in vitro models and is markedly elevated in kidney disease. Left atrial global longitudinal strain (LA GLS) derived by echocardiographic speckle-tracking measures longitudinal shortening of the LA walls, quantifies atrial performance and may enable detection of early LA remodeling in the setting of normal ventricular function. We hypothesized that LA GLS is abnormal in children on hemodialysis (HD) compared to healthy controls of comparable age/sex distribution and that, among HD patients, greater FGF23 levels are associated with abnormal LA GLS. METHODS: Clinical and echocardiographic data from 29 children receiving HD and 13 healthy controls were collected in a cross-sectional single-center study. Plasma FGF23 concentrations were measured using ELISA. The primary outcome was LA GLS measured using 2D speckle-tracking strain analysis. Linear regression analysis was used to investigate predictors of LA GLS in HD. RESULTS: Median dialysis vintage was 1.5 (IQR 0.5-4.3) years. Median intact FGF23 levels were substantially higher in the HD vs. control group (1206 [215, 4707] vs. 51 [43, 66.5] pg/ml; P = 0.0001), and LA GLS was 39.9% SD 11.6 vs. 32.8% SD 5.7 (P = 0.04). Among HD patients, higher FGF23 was associated with lower LA GLS (ß per unit Ln-FGF23: - 2.7; 95% CI slope - 5.4, - 0.1; P = 0.04 after adjustment for age, body size, and HD vintage. FGF23 was not associated with LA phasic reservoir, conduit, or contractile strain. CONCLUSIONS: In children on HD and preserved left ventricular ejection fraction, greater FGF23 is associated with lower LA GLS (indicative of impaired atrial performance). A higher resolution version of the Graphical abstract is available as Supplementary information.