In-depth echocardiographic analysis of left atrial function in healthy adults using speckle tracking echocardiography and volumetric analysis

A review of the pathophysiological mechanisms of doxorubicin-induced cardiotoxicity and aging

The population of cancer survivors is rapidly increasing due to improving healthcare. However, cancer therapies often have long-term side effects. One example is cancer therapy-related cardiac dysfunction (CTRCD) caused by doxorubicin: up to 9% of the cancer patients treated with this drug develop heart failure at a later stage. In recent years, doxorubicin-induced cardiotoxicity has been associated with an accelerated aging phenotype and cellular senescence in the heart. In this review we explain the evidence of an accelerated aging phenotype in the doxorubicin-treated heart by comparing it to healthy aged hearts, and shed light on treatment strategies that are proposed in pre-clinical settings. We will discuss the accelerated aging phenotype and the impact it could have in the clinic and future research.

Left atrial strain is a good predictor of atrio-ventricular synchrony in leadless pacemaker pacing

INTRODUCTION

The importance of atrio-ventricular synchrony pacing in sinus rhythm patients is known. To identify patients in whom leadless pacemakers are able to guarantee this atrio-ventricular synchrony, we explored correlations among echocardiographic measures of left atrial (LA) size and function (doppler parameter and strain) with A4 amplitude in patients implanted with new generation Micra-AV device.

METHODS

After implantation with Micra-AV system, patients underwent device interrogation to evaluate AV synchrony based on the sensing of atrial mechanics and echocardiographic exam to assess LA morphology and LA function.

RESULTS

In the 21 studied patients (14 males, 72 ± 13 years), the A4 wave amplitude values inversely correlated with LA antero-posterior diameter, LA volume, LA contraction strain and LA conduit strain, while they were positively related with LA reservoir strain.

DISCUSSION

Our results indicate a statistically significant relationship between morphological echocardiographic LA parameters and atrial contraction signal (A4), detected by leadless pacemakers and used to synchronize ventricular pacing with the atrium. Instantaneous LA function assessment obtained with LA strain provides incremental information over morphological parameters. LA strain evaluates atrial myocardial deformation during the whole cardiac cycle. We found higher value of A4 in patients that have grater absolute value of LAsr, LAscd and LAsct, that are simple and measurable parameters of LA functional capacity.

CONCLUSION

Preimplant echocardiographic evaluation of the atrial contractility may be useful in predicting adequate A4 sensing and consequently a good atrio-ventricular synchrony pacing. Echocardiography LA strain study seems promising in Micra-AV patient selection.

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

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

The Added Value of Atrial Strain Assessment in Clinical Practice

Speckle tracking echocardiography has emerged as a sensitive tool to analyze myocardial function with improved diagnostic accuracy and prognostic value. Left atrial strain assessment has become a novel imaging method in cardiology with superior prognostic value compared to conventional left atrial volume indices. Left atrial function is divided into three phases, reservoir function being the most important. This review summarizes the added value of speckle tracking echocardiography derived left atrial strain assessment in clinical practice. Recently published data suggest the prognostic value of left atrial reservoir function in heart failure, atrial fibrillation, stroke and valvular heart disease. Furthermore, left atrial reservoir strain proved to be a predictor of cardiovascular morbidity and mortality in the general population. Thus, routine assessment of left atrial function can be an optimal strategy to improve cardiovascular risk prediction and supplement the current risk prediction models.

LA reservoir strain: a sensitive parameter for estimating LV filling pressure in patients with preserved EF

An elevated left ventricular (LV) filling pressure is the main finding in patients with heart failure with preserved ejection fraction (HFpEF), and LV filling pressure is estimated with an algorithm in the recent American Society of Echocardiography (ASE)/European Association of Cardiovascular Imaging (EACVI) guideline. In this study, we sought to determine the efficacy of LA global longitudinal strain to estimate elevated LV filling pressure. Seventy-one consecutive patients (mean age of 63.2  ±  9.75, 70% male) who underwent left ventricular catheterization were included. Transthoracic echocardiography was performed within 24 h before catheterization. The LV filling pressure was estimated using echo parameters based on the 2016 ASE/EACVI algorithm. LA GLS was measured using 2D speckle tracking echocardiography in a four-chamber view (GE, Vivid E9 USA). Invasive LV pre-A pressure corresponding to the mean left atrial pressure (LAP) was used as a reference, and > 12 mm Hg was defined as elevated. Invasive LV filling pressure was defined as elevated in 41 (58%) and normal in 30 patients (42%). The LV filling pressure of 9 (13%) of 71 patients was defined as indeterminate based on the 2016 algorithm. Using the ROC method, 25.5% of LA reservoir strain (LASr) had a higher sensitivity (AUC = 0.79, specificity 77%, sensitivity 80%) in estimating LV filling pressure than the 2016 ASE/EACVI algorithm (AUC = 0.75, specificity 77%, sensitivity 70%). LASr, with higher sensitivity than 2016 ASE/EACVI algorithm, may be used as a single parameter to estimate LV filling pressure and hence may add incremental value toHFpEF diagnosis.

The Prognostic Value of Left Atrial Global Longitudinal Strain and Left Atrial Phasic Volumes in Patients Undergoing Transcatheter Valve Implantation for Severe Aortic Stenosis

INTRODUCTION

The changes and the prognostic implications of left atrial (LA) volumes (LAV), LA function, and vascular load in patients undergoing transcatheter aortic valve implantation (TAVI) for severe aortic stenosis (AS) are less known.

METHODS

We enrolled 150 symptomatic patients (mean age 82 ± 8 years, 58% female, and pre-TAVI aortic valve area 0.40 ± 0.19 cm/m2) with severe AS who underwent 2D transthoracic echocardiography and 2D speckle tracking echocardiography at average 21 ± 35 days before and 171 ± 217 days after TAVI. The end point was a composite of new onset of atrial fibrillation, hospitalization for heart failure and all-cause death (major adverse cardiac events [MACE]).

RESULTS

After TAVI, indexed maximal LA volume and minimum volume of the LA decreased by 2.1 ± 10 mL/m2 and 1.6 ± 7 mL/m2 (p = 0.032 and p = 0.011, respectively), LA function index increased by 6.8 ± 11 units (p < 0.001), and LA stiffness decreased by 0.38 ± 2.0 (p = 0.05). No other changes in the LA phasic volumes, emptying fractions, and vascular load were noted. Post-TAVI, both left atrial and ventricular global peak longitudinal strain improved by about 6% (p = 0.01 and 0.02, respectively). MACE was reached by 37 (25%) patients after a median follow-up period of 172 days (interquartile range, 20-727). In multivariable models, MACE was associated with both pre- and post-TAVI LA global peak longitudinal strain (hazard ratio [HR] 0.75, CI 0.59-0.97; and HR 0.77, CI 0.60-1.00, per 5 percentage point units, respectively), pre-TAVI LV global endocardial longitudinal strain (HR 1.37, CI 1.02-1.83 per 5 percentage point units), and with most of the LA phasic volumes.

CONCLUSION

Within 6 months after TAVI, there is reverse LA remodeling and an improvement in LA reservoir function. Pre- and post-TAVI indices of LA function and volume remain independently associated with MACE. Larger studies enrolling a greater diversity of patients may provide sufficient evidence for the utilization of these imaging biomarkers in clinical practice.

Current clinical applications of speckle tracking echocardiography for assessment of left atrial function

Two-dimensional speckle tracking echocardiography (2D-STE) enables assessment of left atrial (LA) function with better reproducibility and less load dependence than those with conventional methods. Data regarding LA functions determined by 2D-STE in patients with various cardiovascular diseases have recently been accumulating. LA strain has emerged as a novel parameter with the potential of improving the diagnostic accuracy of left ventricular diastolic dysfunction and the prognostic value in patients with heart failure and stroke. Furthermore, LA dysfunction determined by 2D STE can provide incremental prognostic information to conventional echocardiographic parameters in patients with cardiovascular diseases. Hence, 2D-STE appears to be a promising technique for diagnosis and therapeutic decision-making. Data regarding LA functions determined by three-dimensional speckle tracking echocardiography (3D-STE) have also been accumulating. Here, I review recent studies, especially those published after 2016, on clinical applications of LA function assessed by 2D-STE and 3D-STE and summarize the remaining problems to be solved for improving the clinical utility of these techniques.

References Values for Left Atrial Volumes, Emptying Fractions, Strains, and Strain Rates and Their Determinants by Age, Gender, and Ethnicity: The Multiethnic Study of Atherosclerosis (MESA)

RATIONALE AND OBJECTIVES

Left Atrial (LA) adverse remodeling is an important predictor of morbidity and mortality in several cardiovascular (CV) diseases. Our goals were to quantify and provide reference ranges for LA structure and function using feature tracking cine cardiac magnetic resonance.

MATERIALS AND METHODS

2526 participants of the Multiethnic Study of Atherosclerosis study who had feature tracking cine cardiac magnetic resonance derived LA data and were free of atrial fibrillation/flutter and prior CV events at year five follow-up examination (2010-2012) were included in this study. LA phasic indexed volumes: maximum (LAVi max), minimum (LAVi min), and preatrial contraction (LAVi preA); LA empty fractions: total, passive, and active (LAtEF, LApEF, and LAaEF); LA longitudinal strain: maximum and preatrial contraction (S max and S preA); and LA longitudinal strain rate: systolic (SR max) and early/late diastolic (SR e and SR a) were measured. Age, gender, and race/ethnicity-specific reference ranges were identified. Also, reference values in a select subgroup of healthy participants free of traditional CV risk factors at the time of exam date were reported.

RESULTS

The mean ± SD for LAVi max, LAVi min, LAVi preA, S max, SR e, and SR a were in the 45-65-year-old participants: (33.8 ± 10 mL/m²), (14.5 ± 6.4 mL/m²), (24.8 ± 8.2 mL/m²), (34.6 ± 13.8 %), (-1.4 ± 0.7 s^-1), (-2.1 ± 1 s^-1) and in the ≥ 65-year-old participants: (35 ± 11.5 mL/m2), (16.6 ± 8.3 mL/m2), (27.6 ± 9.9 mL/m2), (31.2 ± 14.3 %), (-1 ± 0.6 s^-1), (-2.1 ± 1 s^-1) respectively. Younger individuals had Powered by Editorial Manager and ProduXion Manager from Aries Systems Corporation smaller LA volumes and better LA function compared to their older counterparts. Similar findings were observed in Chinese-Americans as compared to Whites.

CONCLUSION

This study provides reference values of LA structure and function parameters from a healthy multiethnic community-based population aged 53-94 years evaluated by FTMRI.

Impaired Left Atrial Performance Resulting From Age-Related Arial Fibrillation Is Associated With Increased Fibrosis Burden: Insights From a Clinical Study Combining With an in vivo Experiment

Background: Atrial fibrillation (AF) is increasingly considered an age-related degenerative disease, whose process is associated with the development of impaired left atrial (LA) performance. However, the subtle dynamic changes of LA performance in AF during aging have yet to be fully elucidated. Atrial fibrosis is a key substrate for the development of AF, but the progression of fibrosis during aging and its relationship with LA dysfunction need to be further explored. Methods: A total of 132 control individuals and 117 persistent AF patients were prospectively studied. Subjects were further stratified into three age groups (age group 1: younger than 65 years, age group 2: between 65 and 79 years old, and age group 3: older than 80 years). The two-dimensional speckle tracking imaging was carried out for analyzing the alterations in LA function underlying LA remodeling, whereas electroanatomic mapping was performed to investigate LA fibrosis burden. In animal study, aged mice and young mice served as research subjects. Echocardiography and histological staining were used to assess LA performance and fibrosis burden, respectively. Results: Echocardiography showed progressive increases in LA dimension and LA stiffness index, and progressive decreases in LA global longitudinal strain and LA strain rates with advancing age in both AF and control cohorts, which was more prominent in AF cohort. Electroanatomic mapping showed progressive decrease in mean LA voltage and progressive increases in LA surface area, low-voltage area %, and LA volume with advancing age, whereas more significant alterations were observed in AF patients. Moreover, left atrial global longitudinal strain was positively correlated with mean LA voltage, whereas LA stiffness index was negatively related to mean LA voltage. In animal experiment, increased LA size and pulmonary artery dimension as well as longer P-wave duration and more prominent LA fibrosis were found in aged mice. Conclusions: This study provides new evidence of subtle changes in structure and performance of left atrium and their association with atrial fibrosis in both AF and non-AF subjects during physiological aging. In addition, our study also provides normal values for LA structure and performance in both AF and non-AF conditions during aging. These measurements may provide an early marker for onset of AF and LA adverse remodeling.

Left ventricular strain values using 3D speckle-tracking echocardiography in healthy adults aged 20 to 72 years

Three dimensional speckle tracking echocardiography (3D-STE) is a novel modality for the assessment of left ventricular strain (LVS). The aim of our study is to provide single vendor normative strain values measured with 3D-STE in healthy adult caucasians. One hundred fifty-five healthy subjects aged 20 to 72 years (≥ 28 subjects per decile) were prospectively included and examined with 2D and 3D transthoracic echocardiography. In 105 both 3D and 2D-STE were feasible (71%, mean age 44 ± 14 years, 51% female). Mean 3D tangential strain (3D-TS) was − 32 ± 2.9%. 3D global longitudinal strain (3D-GLS) demonstrated a significant but not very strong correlation with 2D-GLS values (− 19.7 ± 1.8% vs − 20.4 ± 2.2%, r = 0.462, p < 0.001). No gender difference was observed in 3D strain parameters. 3D-GLS decreased with increasing age stratum (p = 0.024). LVEF was associated with 3D-TS and 3D-GLS (r =  − 0.819, p ≤ 0.001 for 3D-TS, p =  − 0.477, r < 0.001, p = 0.001 for 3D-GLS). In this single vendor study age and gender-specific normative LV 3D-TS values were reported for healthy adult caucasians. In a significant proportion of the subjects 3D-STE was not feasible, but when feasible, 3D-STE shows excellent association with LVEF, and is therefore a promising novel modality for the assessment of the myocardial function, provided that issues of limited feasibility and temporal resolution are addressed.

In-depth echocardiographic analysis of left atrial function in healthy adults using speckle tracking echocardiography and volumetric analysis

Purpose

Left atrial (LA) dilatation is predictive for complications in a multitude of cardiac diseases; therefore, adequate assessment is essential. Technological advances have made it possible to quantify LA function with Speckle Tracking Echocardiography (STE); however, there are currently no recommendations for normal values with regard to LA function. We aimed to assess LA myocardial and volumetric function in a healthy cohort and investigate correlations with baseline characteristics.

Methods

This prospective cohort study included 147 (aged 20–72) healthy individuals and assessed LA volumetric function using maximum, minimum and pre‐a‐wave volumes and myocardial function using reservoir function using peak strain in LA relaxation (LA‐strain), conduit function using peak strain rate in early LA contraction (LA‐SRe) and pump function using peak strain rate in late LA contraction (LA‐SRa).

Results

Mean LA‐strain was 39.7 ± 6.2%, LA‐SRe −2.78 ± 0.62 s⁻¹ and LA‐SRa −2.56 ± 0.62 s⁻¹. Subjects were divided into 5 age decades (each 50% female). LA‐strain and LA‐SRe were lower in the oldest groups, whereas LA‐SRa was higher. LA‐SRa was higher in males(−2.69 ± 0.68 s⁻¹ vs −2.42 ± 0.52 s⁻¹). Age‐specific values are provided. Age proved to be an independent predictor for LA‐SRa after correction for blood pressure and heart rate. LA expansion index and passive emptying fraction decreased with age, while active emptying fraction increased with age. LA maximum volume did not increase with age.

Conclusion

This study provides normal values for the three phasic functions of the LA, assessed with STE and volumetric function. Our results suggest the need for age‐specific reference ranges, and normal values for this cohort have been calculated.