Detection of Left Atrium Myopathy Using Two-Dimensional Speckle Tracking Echocardiography in Patients with End-Stage Renal Disease on Dialysis Therapy

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.

New-onset atrial fibrillation following arteriovenous fistula increases adverse clinical events in dialysis patients with end-stage renal disease

Background

End-stage renal disease (ESRD) patients have a high potential cardiovascular burden, and cardiovascular disease (CVD) is the leading cause of death in maintenance haemodialysis (MHD) patients. Arteriovenous fistula (AVF) is the preferred vascular access for MHD patients, but AVF significantly affects the haemodynamics of the cardiovascular system, leading to or exacerbating CVD, including atrial fibrillation (AF). This study aimed to evaluate the impact of AVF on cardiac function, especially of the left atrium (LA), in patients with ESRD and to further explore the relationship between AVF establishment and the occurrence of AF.

Methods

We selected 1,107 ESRD patients on haemodialysis using AVF and 550 patients with tunneled-cuffed catheters (TCC) admitted between January 2016 and December 2022 for follow-up to compare the rate of AF between the two groups. A total of 153 patients in the AVF group with complete information (clinical data, echocardiographic and biochemical indices, and other data) were enrolled and retrospectively analysed for risk factors for the development of AF and were followed up for adverse clinical outcomes (including all-cause death, cardiac death, readmission due to heart failure, and stroke).

Results

The incidence of new-onset AF was higher in the AVF group than the TCC group after dialysis access was established (16.30% vs. 5.08%, P < 0.001). Echocardiography showed that the LA anteroposterior diameter increased (P < 0.001) and the incidence of AF increased from 11.76% to 26.14% (P = 0.001) after AVF establishment. Multivariate logistic regression analysis showed that age and LA enlargement were independent risk factors for new-onset AF after AVF establishment (P < 0.05). Adverse clinical outcomes were more common in patients with AF than in patients without AF (P < 0.001). Multivariate Cox risk regression analysis suggested that new-onset AF (HR = 4.08, 95% CI: 2.00-8.34, P < 0.001) and left ventricular systolic dysfunction (HR = 2.42, 95% CI: 1.20-4.88, P = 0.01) after AVF establishment were independent risk factors for adverse clinical outcomes.

Conclusion

LA enlargement after AVF establishment is associated with a significant increase in the incidence of AF, in addition, AF which is as an important influential factor in patients with MHD combined other systemic diseases might increase adverse clinical events.

Clinical Trial Registration

(NCT06199609).

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 (β 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.

Comparison of left atrial deformation parameters between renal transplant and hemodialysis patients

Background

Renal transplantation (RT) has been demonstrated to improve left ventricular systolic function. However, only few studies have attempted to reveal the effects of transplantation on left atrial (LA) function. In our study, we aimed to compare LA function between RT and hemodialysis patients.

Methods

This cross-sectional study included 75 consecutive patients with RT, and 75 age- and gender-matched patients on maintenance hemodialysis. LA strain and strain rate (SR) analyzed by two-dimensional (2D) speckle tracking echocardiography (STE) were compared between the groups in addition to standard echocardiographic parameters.

Results

LA strain during reservoir phase (29.88 ± 5.76% vs 26.11 ± 5.74%, P < .001), LA strain during conduit phase (− 15.28 ± 5.00% vs − 12.92 ± 4.38%, P = .003), and LA strain during contraction phase (− 14.60 ± 3.32% vs − 13.19 ± 3.95%, P = .020) were higher in the transplantation group. Similarly, LA peak SR during reservoir phase (1.54 ± 0.33 s^− 1 vs 1.32 ± 0.33 s^− 1, P < .001), LA peak SR during conduit phase (− 1.47 ± 0.49 s^− 1 vs − 1.12 ± 0.42 s^− 1, P < .001), and LA peak SR during contraction phase (− 2.13 ± 0.46 s^− 1 vs − 1.83 ± 0.58 s^− 1, P = .001) were higher in the transplantation group as well.

Conclusions

LA function assessed by 2D STE was better in RT patients than hemodialysis patients. This may suggest favorable effects of RT on LA function.

Left atrial strain: A novel "biomarker" for chronic kidney disease patients?

Cardiovascular disease and chronic kidney disease are frequently inter-connected and this association leads to an exponential growth of cardiovascular risk. This risk is currently underestimated by the existing algorithms and there is a constant need for new markers to predict adverse outcomes in this special population. In general population left atrial strain has emerged as an important tool for both the diagnosis and prognostic stratification, but data regarding its role in chronic kidney disease patients is scarce. The purpose of this review is to summarize the current evidence regarding this matter. Left atrial size and function mirror the duration and severity of increased left ventricular filling pressures. Increased left atrial volume index and impaired left atrial strain parameters are independent predictors for adverse cardiovascular events. Left atrial strain is impaired before changes in volume appear, thus being able to predict both diastolic and systolic function in chronic kidney disease patients. Finally, left atrial strain can identify renal patients with impaired exercise capacity and this could have clinical applications in the rehabilitation of this patients.

Assessment of subclinical left atrial myocardial dysfunction in essential hypertension patients with normal left ventricle function by two-dimensional strain and volume-derived variables

PURPOSE

To investigate subclinical left atrial (LA) myocardial dysfunction in essential hypertension (EHT) patients by using volume-derived and two-dimensional strain.

METHODS

We enrolled in this study 51 normal subjects and 95 EHT patients. The LA volume-derived index was measured in apical 4- and 2-chamber views. LA strain and strain rate, reservoir, conduit, and booster pump functions were measured by two-dimensional speckle tracking echocardiography (STE).

RESULTS

LA ejection fraction (LAEF) and absolute strain-derived values were significantly lower in EHT patients than in controls. LAEF (total, passive), absolute values of LA strain (S-reservoir and S-conduit), and strain rate (Sr-reservoir and Sr-conduit) were significantly lower in EHT patients with left ventricular hypertrophy (LVH) than in patients without LVH and in controls. However, there were no significant difference in active LAEF or S-booster pump and Sr-booster pump functions between EHT patients without LVH and normal subjects. The areas under the curves of the combination of volume-derived values, LA strain, and strain rate were significantly higher than those of individual indices.

CONCLUSION

In our population, EHT patients showed impaired LA functions and greater stiffness than normal subjects. EHT patients with LVH showed greater impairment of LA reservoir and conduit functions than patients without LVH. EHT patients without LVH had normal LA booster pump function, which was impaired in patients with LVH. Volume-derived and 2D strain values could provide a sensitive and reproducible method for detecting subclinical LA myocardial dysfunction in EHT.

Diagnostic accuracy of left atrial remodelling and natriuretic peptide levels for preclinical heart failure

AIMS

Left atrial (LA) remodelling is an important predictor of cardiovascular events of heart failure (HF) and atrial fibrillation. Data regarding diagnostic value of LA remodelling on diastolic dysfunction (DD) and preclinical HF remain largely unexplored.

METHODS AND RESULTS

We assessed LA dimension (LAD) in 8368 consecutive asymptomatic Asians (mean age: 49.7, 38.9% women) and related such measure to updated American Society of Echocardiography (ASE) DD criteria and newly revised N-terminal pro-brain natriuretic peptide (NT-proBNP) cut-off (≥125 pg/mL) and HF with preserved ejection fraction criteria incorporating NT-proBNP and echocardiography parameters by the European Society of Cardiology (ESC). LAD and indexed LAD (LADi) were both inversely correlated with myocardial relaxation e' and positively associated with indexed LA volume, left ventricular E/e', and tricuspid regurgitation velocity (all P < 0.001) and showed significantly graded increase across ASE-defined 'normal', 'inconclusive', and 'DD' categories (30.9, 34.4, and 36.5 mm; 16.7, 19.1, and 20.6 mm/m² , for LAD/LADi, both P for trend: <0.001, respectively). Substantial differences of LAD/LADi (31.3 vs. 33.6 mm/16.7 vs. 19.2 mm/m² , both P < 0.001) between ESC low and high HF probability using NT-proBNP cut-off were also observed. Multivariate linear and logistic models demonstrated that LAD set at 34 mm was independently associated with ASE-defined diastolic indices, DD existence, and elevated NT-proBNP (all P < 0.05). The use of LAD further yielded high diagnostic accuracy in DD (area under receiving operative characteristic curve: 0.77, 95% confidence interval [0.73, 0.80]; negative predictive value: 97.9%) and in ESC-recommended HF with preserved ejection fraction criteria (area under receiving operative characteristic curve: 0.70, 95% confidence interval [0.65, 0.75]; negative predictive value: 98.7%) with high predictive value in LA remodelling (>34 mL/m² ; positive predictive value: 96%) and well-discriminated ESC-recommended NT-proBNP (≥125 pg/mL, LAD: 37 mm) for HF.

CONCLUSIONS

Single utilization of atrial remodelling is highly useful for ruling out presence of DD and provides practical threshold for identifying preclinical HF based on most updated guidelines.

Association of the plasma aldosterone concentration, left atrial deformation and ambulatory blood pressure in never-treated early hypertensive patients

Left atrial (LA) strain is known to exhibit an early progressive reduction in hypertensive patients with diastolic dysfunction. However, an association of the renin-angiotensin-*aldosterone system (RAAS) with LA deformation has not been found in these patients. We aimed to investigate the association of plasma aldosterone concentration (PAC) and 24-hour ambulatory blood pressure monitoring (ABPM) with LA and left ventricle (LV) deformation in never-treated early hypertensive patients. This cross-sectional study included 101 never-treated subjects who were registered in a working group at The Catholic University of Korea. The patients were divided into a hypertension group (n = 71), which was defined as having a systolic blood pressure (BP) ≥130 mm Hg and/or a diastolic BP ≥80 mm Hg based on ABPM, and a control group (n = 30). Enrolled patients underwent conventional and speckle tracking echocardiography, ABPM, and measurement of pulse wave velocity, PAC, and plasma renin activity. Compared with the control group, the hypertension group had significantly increased PAC, global longitudinal strain (GLS), atrial reservoir strain, atrial pump strain, and atrial systolic strain rate. LA pump strain was independently associated with nighttime systolic BP. PAC was correlated with GLS but not LA deformation in hypertensive patients without clinically apparent target organ damage. The raised LV pressure secondary to the nocturnal systemic pressure overload might be more strongly associated with LA deformation than with the RAAS.

The occurrence of atrial fibrillation in dialysis patients and its association with left atrium volume before and after dialysis

PURPOSE

Atrial fibrillation is a serious problem, especially in patients on dialysis. The prevalence of AF in this group of patients is higher than in general population and associated with increased mortality. The aim of this study was to assess the risk of the occurrence of atrial fibrillation related to intradialysis hypotension and left atrium volume enlargement associated with dialysis. The influence of dialysis session on: E/E', V LA, E/A, E', V RA and the width of inferior vena cava of RV was analyzed.

METHODS

This study included 40 patients on hemodialysis. Echocardiographic examination was performed to assess heart condition and function, the presence of LVH and systolic and diastolic function disturbances, LV mass, LA size, LAV, RAV, E/A, E', E/E, ejection fraction in all patients before and after dialysis. Moreover, all patients had ECG Holter continuously recording heart's rhythm before and after dialysis to assess the occurrence of atrial fibrillation related to dialysis session.

RESULTS

The analysis of differences in echocardiographic parameters before and after dialysis demonstrated significantly greater left atrium volume, right atrium volume, width of inferior vena cava and e' parameter before dialysis in comparison with post-dialysis state. Significantly higher incidence of AF after dialysis was seen. Volume of left atrium exceeding 32 mm (cutoff value) was observed significantly more often in patients before dialysis. No association was observed between left ventricle mass and left atrium volume.

CONCLUSIONS

The dialysis procedure may be a trigger for atrial fibrillation and thus AF preventive measures should be introduced in dialysis patients.

Evaluation of the association between diabetic retinopathy and the incidence of atrial fibrillation: A nationwide population-based study

BACKGROUND

Atrial fibrillation (AF) is prevalent among type 2 diabetic patients. However, the association between diabetic retinopathy (DR) and AF is controversial.

METHODS

We included 40,500 patients with type 2 diabetes (≥40years, mean age 62±11years, 53% men) without AF from the Korean National Insurance Service-National Sample Cohort (2002-2007). Subjects were classified without DR (non-DR, n=30,178), with DR (DR, n=8920), and with proliferative DR (PDR, n=1402).

RESULTS

During a mean 5.9-year follow-up, 1261 (3.1%) patients were newly diagnosed as having AF (4.9, 6.0, and 8.3 per 1000 person-years in the non-DR, DR, and PDR groups, respectively). In multivariate Cox proportional hazard models, patients in the DR and PDR groups had a significantly higher risk of AF than those in the non-DR group (DR group: hazard ratio [HR] 1.14, 95% confidence interval [CI] 1.00-1.30; PDR group: HR 1.46, 95% CI 1.13-1.87); p for trend <0.001). The risk of AF increased in patients with DR and end-stage renal disease (ESRD) (HR 2.39, 95% CI 1.31-3.96, p<0.001) and in those with PDR and ESRD (HR 3.59, 95% CI 1.96-5.97, p<0.001) compared to those without DR and ESRD.

CONCLUSIONS

The presence and severity of DR was significantly associated with the incidence of AF. Also, the presence of ESRD had an impact on the incidence of AF in patients with DR.