Minimal Left Atrial Volume Research Articles

Left atrial strain as an independent predictor of sinus rhythm maintenance after catheter ablation for paroxysmal atrial fibrillation in HFpEF patients

Abstract Funding Acknowledgements Type of funding sources: None. Background The early AF treatment by radio-frequency catheter ablation is very important for improving clinical outcome in patients with history of atrial fibrillation (AF) and heart failure with preserved ejection fraction (HFpEF). Left atrial (LA) strain showed to be a useful index to monitor atrial function in AF and HFpEF states. However, the accuracy of LA strain to predict the long-term maintenance of sinus rhythm (SR) in HFpEF patients with paroxysmal AF undergoing catheter ablation is still under debate. Aims To define the best echocardiography derived parameters to predict the long-term maintenance of SR in paroxysmal AF patients with high probability of HFpEF undergoing catheter ablation. Methods We prospectively enrolled (between September 2017 and May 2019) 200 consecutive patients (62 ± 10 years, 58% males) with dyspnea (NYHA≥II), paroxysmal AF and preserved LV ejection fraction (≥50%). All patients had a H2FPEF score suggesting high probability of HFpEF. During sinus rhythm, all patients underwent comprehensive transthoracic echocardiography at baseline, including assessment of left ventricular (LV) global longitudinal strain (GLS), left atrial (LA) reservoir strain (LASr), LA conduit strain (LAScd) and LA contractile strain (LASct) using two-dimensional speckle tracking in apical views. Results After 42+/-8 months follow-up, a total of 34 (17%) patients had a documented recurrence of AF. Patients with AF recurrence had lower LASr (22.2% vs. 28.3%, p < 0.001) and LASct (10.9% vs. 13.2%, p < 0.01) compared to patients who keep on SR. Among speckle tracking derived LA phasic strain indices, LASr showed the largest area under the curve (AUC = 0.8, p < 0.001) and the strongest independent predictive value (LASr > 22%) of long-term maintenance of SR with sensitivity of 80% and specificity of 66% (Figure 1). Other parameters of LA function, LA diameter, maximum or minimum LA volume index, LV GLS or ejection fraction, and indices of LV diastolic function had lower area under the curve. Using multivariable logistic regression, only LASr (OR 0.89, 95% CI 0.81-0.97, p=0.013) was independently associated with long-term SR maintenance while other LA size and function indices were not. Conclusion In HFpEF patients with paroxysmal AF undergoing catheter ablation, LASr is more accurate predictor of SR maintenance than other standard echocardiographic parameters in long-term follow-up. Figure 1: Receiver-operating characteristic curves of left atrial reservoir strain (LASr), LA conduit strain (LAScd) and LA contractile strain (LASct), LA emptying fraction (LAEF), LA expansion index (LAEI), LA end-systolic (LAES) and end-diastolic (LAED) volume index (VI) to predict long-term maintenance of sinus rhythm.

Echocardiographic assessment of pulmonary capillary wedge pressure in patients with frequent premature ventricular complexes.

Premature ventricular complex (PVC) is seen in most individuals. It has been shown that the kinetics-tracking index or Kawasaki-Tanaka index (KT index) strongly predicts pulmonary capillary wedge pressure (PCWP) by noninvasively. KT index was defined as log10 (active LAEF/minimum LAV index). We goaled to assess PCWP non-invasively in patients with frequent PVCs with normal left ventricular systolic functions and to evaluate whether there is an increase in PCWP before systolic and diastolic functions are impaired. About 55 patients with frequent PVCs as a patient group and 54 healthy volunteers as a control group were involved to the study. After the conventional echocardiographic examination, the vendor-independent software system (EchoPAC version 202) was used to obtain the time-left atrial volume (LAV) curve. total left atrial emptying function (LAEF), passive LAEF, and active LAEF were calculated to evaluate phasic left atrial (LA) function. In this study, ePCWP was calculated using the KT index, and KT index results and other echocardiographic parameters were compared between study groups. LA anterior-posterior dimension, LA maximum volume index, and LA minimum volume index were significantly larger in the patient group (all p values<.001). Total LAEF were significantly reduced in patients with frequent PVC (p<.001). Estimated pulmonary capillary wedge pressure (ePCWP) by KT index was significantly higher in patients with frequent PVCs (p< .001). Patients with frequent PVC had increased ePCWP as assessed by KT index.

Predicting new onset atrial fibrillation post acute myocardial infarction: Echocardiographic assessment of left atrial size.

Atrial fibrillation (AF) commonly occurs following acute myocardial infarction (AMI). Left atrial (LA) size has been reported to predict new onset AF in this cohort, however, the optimal metric of left atrial size for risk stratification following AMI is unknown. Patients presenting to a tertiary hospital with incident AMI (NSTEMI or STEMI) and no history of AF were recruited. All patients underwent guideline-based workup and management for AMI, including transthoracic echocardiographic assessment. Three alternative metrics of left atrial size were determined: LA area, maximal and minimal LA volume indexed to body surface area (LAVImax and LAVImin). The primary endpoint was new onset AF diagnoses. Four hundred thirty three patients were included in the analysis, of which 7.1% had a new diagnosis of AF within a median follow-up of 3.8 years. Univariate predictors of incident AF included age, hypertension, revascularization with CABG, NSTEMI presentation, right atrial area, and all three metrics of LA size. Among three multivariable models created for the prediction of new onset AF utilizing alternate metrics of LA size, LAVImin was the only LA size metric found to be an independent predictor. LAVImin is an independent predictor of new onset AF post AMI. LAVImin outperforms echocardiographic assessment of diastolic dysfunction and alternative metrics of LA size (including LA area and LAVImax) for risk stratification. Further studies are needed to validate our findings in post AMI patients, and evaluate whether LAVImin holds similar advantages over LAVImax in other cohorts.

The effect of urgent blood pressure reduction on left atrial strain in patients with hypertensive attack : Blood pressure lowering affects LA strain.

Left atrial (LA) strain is a robust measure of LA function and is a useful parameter to assess left ventricular filling pressure. While initially considered as a "load-independent" parameter of LA function, later studies have found that acute changes in LA preload may affect LA reservoir and contractile strains. Acute alterations in blood pressure (BP) induces a change in left ventricular (LV) filling pressure without imposing a volume load, thus providing an opportunity to assess the effects of the change in LA afterload on LA mechanics. This study aims to understand the effect of acute BP changes on LA strain. A total of 40 patients admitted to the emergency department with hypertensive urgency were included. All patients underwent a comprehensive echocardiographic examination including measurement of LA reservoir, conduit and contractile strains. A repeat set of measurements were obtained after BP lowering. Average drop in mean BP following intervention was 18.1 ± 5.4%. LV end-systolic and end-diastolic volumes, as well as maximum and minimum LA volumes were decreased significantly after BP reduction. The absolute increases in reservoir and contractile strains were 2.3 ± 4.7% (7.9% ± 13.8% relative to baseline) and 2.5 ± 3.3% (13.5 ± 19.0% relative to baseline), respectively, with both changes being statistically significant (p = 0.003 for reservoir and p < 0.001 for contractile strains). There were no significant changes in conduit strain after BP intervention (p = 0.79). The change in both LA reservoir and contractile strains were more evident in those with a previous diagnosis of hypertension and those with a smaller degree of change in mean BP after intervention. In patients with an acute hypertension, lowering BP leads to an acute improvement in LA reservoir and contractile strains. Thus, acute changes in systemic BP should be considered when LA mechanics are evaluated.

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 (LAV_max and LAV_min, respectively). LAV_max and LAV_min remained significantly increased in AF patients when indexing to either body surface area (LAV_max/BSA and LAV_min/BSA, respectively), left ventricle length in end diastole (LAV_max/LVLd and LAV_min/LVLd, respectively), or late mitral annular diastolic velocity (LAV_max/a’ and LAV_min/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 (LAV_min, LAV_min/BSA, LAV_min/LVLd, LAV_min/a’, LAV_max/a’, LAEF, LAEi, and PALS) (p ≤ 0.05) but no structural measures (LAV_max, LAV_max/BSA, and LAV_max/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.

Left atrial function evaluation by 2D speckle-tracking echocardiography in patients with vasovagal syncope.

Evidence indicates left atrial (LA) involvement in vasovagal syncope (VVS). The LA regulates left ventricular filling during the cardiac cycle. We aimed to assess LA function in patients with VVS by 2D speckle-tracking echocardiography. Sixty-nine consecutive patients with VVS were recruited. Based on the head-up tilt test (HUTT) results, the study population was divided into two groups: HUTT+ (n = 45) and HUTT- (n = 24). Fifty-one consecutive subjects were enrolled as the control group. LA myocardial deformation parameters were measured by 2D speckle-tracking echocardiography to evaluate LA function. Maximal, minimal, and pre-P LA volumes were lower in patients with VVS. Strain and strain rate during reservoir, conduit, and contraction phases in VVS patients with HUTT+ or HUTT- were not statistically significantly different from those in the control group. Additionally, the volumetric parameters of LA function showed no difference in statistical significance between the three study groups. While LA phasic function was not different between the two groups of VVS patients with HUTT+ or HUTT- and the control group, LA size during the three LA phases was smaller in patients with VVS.

Left atrial dysfunction can independently predict exercise capacity in patients with chronic heart failure who use beta-blockers

BackgroundBeta-blockers are first-line clinical drugs for the treatment of chronic heart failure (CHF). In the guidelines for cardiac rehabilitation, patients with heart failure who do or do not receive beta-blocker therapy have different reference thresholds for maximal oxygen uptake (VO2max). It has been reported that left atrial (LA) strain can be used to predict VO2max in patients with heart failure, which can be used to assess exercise capacity. However, most existing studies included patients who did not receive beta-blocker therapy, which could have a heterogeneous influence on the conclusions. For the vast majority of CHF patients receiving beta-blockers, the exact relationship between LA strain parameters and exercise capacity is unclear.MethodsThis cross-sectional study enrolled 73 patients with CHF who received beta-blockers. All patients underwent a thorough resting echocardiogram and a cardiopulmonary exercise test to obtain VO2max, which was used to reflect exercise capacity.ResultsLA reservoir strain, LA maximum volume index (LAVImax), LA minimum volume index (LAVImin) (P < 0.0001) and LA booster strain (P < 0.01) were all significantly correlated with VO2max, and LA conduit strain was significantly correlated with VO2max (P < 0.05) after adjusting for sex, age, and body mass index. LA reservoir strain, LAVImax, LAVImin (P < 0.001), and LA booster strain (P < 0.05) were significantly correlated with VO2max after adjusting for left ventricular ejection fraction, the ratio of transmitral E velocity to tissue Doppler mitral annulus e′ velocity (E/e′), and tricuspid annular plane systolic excursion. LA reservoir strain with a cutoff value of 24.9% had a sensitivity of 74% and specificity of 63% for the identification of patients with VO2max < 16 mL/kg/min.ConclusionAmong CHF patients receiving beta-blocker therapy, resting LA strain is linearly correlated with exercise capacity. LA reservoir strain is a robust independent predictor of reduced exercise capacity among all resting echocardiography parameters.Clinical Trial registration: This study is a part of the Baduanjin-Eight-Silken-Movement with Self-efficacy Building for Patients with Chronic Heart Failure (BESMILE-HF) trial NCT03180320 (ClinicalTrials.gov, registration date: 08/06/2017).

Reference data for left ventricular filling and atrial function in children using cardiovascular magnetic resonance

BackgroundDiastolic dysfunction is associated with morbidity and mortality in multiple pediatric disease processes. Cardiovascular magnetic resonance (CMR) provides a non-invasive method of studying left ventricular (LV) diastolic dysfunction through the assessment of LV filling curves and left atrial (LA) volume and function. However, there are no normative data for LV filling curves and the standard method is time-intensive. This study aims to compare an alternate, more rapid method of obtaining LV filling curves to standard methodology and report normative CMR diastolic function data for LV filling curves and LA volumes and function. MethodsNinety-six healthy pediatric subjects (14.3 ± 3.4 years) with normal CMR defined by normal biventricular size and systolic function without late gadolinium enhancement were included. LV filling curves were generated by removing basal slices without myocardium present throughout the cardiac cycle and apical slices with poor endocardial delineation (compressed method), then re-generated including every phase of myocardium from apex to base (standard method). Indices of diastolic function included peak filling rate and time to peak filling. Systolic metrics included peak ejection rate and time to peak ejection. Both peak ejection and peak filling rates were indexed to end-diastolic volume. LA maximum, minimum and pre-contraction volumes were calculated using a biplane method. Inter-and intra-observer variability were assessed with intraclass correlation coefficient. Multivariable linear regression was used to assess the effects of body surface area (BSA), gender and age on metrics of diastolic function. ResultsBSA had the largest effect on LV filling curves. Normal LV filling data are reported for both compressed and standard methods. The time to perform the compressed method was significantly shorter than the standard method (median 6.1 min vs. 12.5 min, p < 0.001). Both methods had strong to moderate correlation for all metrics. Intra-observer reproducibility was moderate to high for all LV filling and LA metrics except for time to peak ejection and peak filling. ConclusionsWe report reference values for LV filling metrics and LA volumes. The compressed method is more rapid and produces similar results to standard methodology, which may facilitate the use of LV filling in clinical CMR reporting.

Assessment of fetal left atrial volume and function using anovel left atrial volume tracking method.

Several fetal cardiovascular structural defects may alter the hemodynamics of the cardiac chambers resulting in changes in chamber sizes. Quantitative measurements of the sizes of cardiac chambers can augment the diagnostic power of fetal echocardiography. Using a new left atrial volume tracking (LAVT) method, time-left atrial volume curves (TLAVCs) can be automatically obtained. The goal of this study was to examine whether this method can be used to evaluate left atrial volume (LAV) and provide reference values for LAV and indices of left atrial function in normal human fetuses. Two hundred and four normal human fetuses were enrolled. Using LAVT, the maximal left atrial volume (LAVmax) and minimal left atrial volume (LAVmin) were measured from TLAVCs. Left atrial ejection fraction (EF) was calculated. The maximal left atrial area (LAAmax) and minimal left atrial area (LAAmin) were measured using manual method tracing. Between 21 and 40 weeks, mean LAVmax increased from 0.27 ml to 4.15 ml, and mean LAVmin increased from 0.13 ml to 2.26 ml, respectively, while the EF remained stable at around 0.43. From 21 to 40 weeks, mean LAAmax increased from 0.61 cm2 to 2.64 cm2, and mean LAAmin increased from 0.34 cm2 to 1.53 cm2. This study establishes reference values for fetal LAV during the second half of gestation. The LAVT method appears to be feasible in estimating fetal LAV and shows potential for assessing left atrial function.

Association of left atrial ejection fraction and cardiovascular outcomes in Asian patients with hypertrophic cardiomyopathy

Abstract Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): National University of Singapore Yong Loo Lin School of Medicine's Junior Academic Fellowship Scheme Background The optimal method of risk stratification of hyp­ertrophic cardiomyopathy (HCM) patients, especially in the Asian population, is unknown. Left atrial ejection fraction (LAEF) is an emerging risk marker for cardiovascular outcomes. This study aimed to investigate whether LAEF was associated with cardiovascular outcomes in Asian patients with HCM. Methods This was a retrospective cohort study performed in a tertiary academic centre involving 291 consecutive patients diagnosed with HCM between 2010 and 2017. We collected the relevant clinical characteristics of these patients and retrospectively analysed the index transthoracic echocardiograms for novel left atrial indices including LAEF. We obtained the maximum (LAVmax) and minimum left atrial volumes (LAVmin) using the biplane method of disks in apical 4- and 2-chamber views. LAEF was derived by dividing the difference between LAVmax and LAVmin by LAVmax. We assessed the patients for outcomes of (1) heart failure requiring admission, and (2) a composite of adverse outcomes including all-cause mortality, ventricular tachycardia / ventricular fibrillation (VT/VF) events, appropriate device therapy if an implantable cardioverter defibrillator (ICD) was implanted, stroke and heart failure hospitalization. Results The patients had a mean age of 59.0 ± 16.7 years-old at diagnosis and had a male preponderance (71.2%). The most common comorbidities were hypertension, diabetes mellitus and ischemic heart disease. On univariable logistic regression analysis, maximum and minimum left atrial volume index (LAVI) as well as LAEF showed a significant association with heart failure and the predefined composite outcome. On Cox regression analysis adjusting for variables of age, sex, left ventricular ejection fraction (LVEF), left ventricular maximal wall thickness &amp;gt;30mm, significant left ventricular outflow tract (LVOT) gradient of &amp;gt; 30mmHg and more than moderate mitral regurgitation, maximum and minimum LAVI as well as LAEF retained an association with heart failure admission but only minimum LAVI and LAEF were associated with the composite outcome [(OR 0.019, 95% CI 0.02-0.230, p=0.002), (OR 0.226, 95% CI 0.053-0.960, p=0.044), (OR 1.030, 95% CI 1.016-1.045, p&amp;lt;0.001), and (OR 1.016, 95% CI 1.005-1.026, p=0.004) respectively]. Conclusion LAEF was an independently associated with congestive heart failure as well as a composite of adverse outcomes in Asian patients with HCM.

226 ECHOCARDIOGRAPHIC AND INVASIVE EVALUATION OF LEFT ATRIAL PRESSURE IN PATIENTS UNDERGOING CATHETER ABLATION FOR ATRIAL FIBRILLATION

Abstract Aims Estimation of left ventricle (LV) filling pressure is one of the most important parameters to provide information in clinical practice. However, the challenging in investigating this parameter through invasive methods makes it difficult to be used. The study aims to investigate the association between cardiac structure and function derived by transthoracic echocardiography (TTE) and left atrial (LA) invasive pressure (LAP). Methods The study was a multi-center prospective study enrolling 73 patients (mean age 65 ± 8, 27% female) undergoing primary catheter ablation for AF. Patients were evaluated and enrolled from June 2021 to April 2022. Complete TTE assessing measures of LV, LA and right ventricle (RV) structure and function including speckle tracking echocardiography, was performed at baseline. Echocardiographic data have been assessed the same day of the invasive measurement of the LAP during AF ablative procedure. Linear regression analysis has been performed to assess the relationship between measures of cardiac structure and function and LAP. Logistic regression analysis assessed the parameters associated with elevated LAP (≥ 15mmHg). Results Baseline clinical characteristics of the study population did not differ according to elevated LAP vs. non-elevated LAP. Patients with elevated LAP showed instead abnormal measures of LV global longitudinal strain, measures of LA structure and function, except for LA maximal volume, and RV structure and function. After multivariable adjustment, including demographic factors and comorbidities, E/e`(p = 0,024), LA minimal volume (p = 0,009), LA emptying fraction (LAEF) (p = 0,012), LA Reservoir (p = 0,039), TAPSE (p = 0,010) and RV free wall strain (p = 0,028), but not LA maximal volume (p = 0,11), were significantly associated with LAP. Similarly, these measures, but nor LA maximal volume, were significant determinants of elevated LAP. Overall, LA minimal volume and LAEF showed the best diagnostic accuracy to predict elevated LAP (AUC 0.72 and 0.73, respectively). Conclusions Novel measures of LA structure and function, but not standard assessment by LA maximal volume, were significantly associated with LAP in patients affected by AF. These measures, along with measures of LV and RV function may be used in the diagnostic assessment of filling pressure in ambulatory settings.

Differing Impact of Preterm Birth on the Right and Left Atria in Adulthood.

Background Preterm birth affects 10% of live births and is associated with an altered left ventricular and right ventricular phenotype and increased cardiovascular disease risk in young adulthood. Because left atrial (LA) and right atrial (RA) volume and function are known independent predictors of cardiovascular outcomes, we investigated whether these were altered in preterm-born young adults. Methods and Results Preterm-born (n=200) and term-born (n=266) adults aged 18 to 39 years underwent cardiovascular magnetic resonance imaging. LA and RA maximal and minimal volumes (absolute, indexed to body surface area, and as a ratio to ventricular volumes) were obtained to study atrial morphology, while LA and RA stroke volume, strain, and strain rate were used to assess atrial function. Secondary analyses consisted of between-group comparisons based on degree of prematurity. Absolute RA volumes and RA volumes indexed to right ventricular volumes were significantly smaller in preterm-born compared with term-born adults. In addition, RA reservoir and booster strain were higher in preterm-born adults, possibly indicating functional compensation for the smaller RA volumes. LA volumes indexed to left ventricular volumes were significantly greater in preterm-born adults as compared with term-born adults, although absolute LA volumes were similar between groups. LA and RA changes were observed across gestational ages in the preterm group but were greatest in those born very-to-extremely preterm. Conclusions Preterm-born adults show changes in LA and RA structure and function, which may indicate subclinical cardiovascular disease. Further research into underlying mechanisms, opportunities for interventions, and their prognostic value is warranted.

Could premature ventricular contractions lead to atrial remodeling?

Premature ventricular contraction (PVC) is a frequent kind of arrhythmia that affects around 1% of the general population. While PVC most frequently impairs ventricular function in structurally normal heart, retrograde ventriculo-atrial conduction can occur in people with PVC. These retrograde atrial activations may mimic pulmonary vein-derived atrial ectopies. As a result, PVC may raise the risk of atrial fibrillation (AF) by retrograde ventriculo-atrial conduction. The Four-Dimensional Automated Left Atrial Quantification (4D Auto LAQ) tool is a left atrial analytical approach that utilizes three-dimensional volume data to quantify the volume, as well as LA longitudinal and circumferential strains. The purpose of this study was to determine if clinical diagnosis of PVC is connected with abnormal LA function as determined by LA strain evaluation utilizing a 4D Auto LAQ compared to the healthy population. The 58 patients with frequent PVCs and 53 healthy volunteers as a control group were enrolled in the study. Imaging was performed using the GE Vivid E95 echocardiography equipment (GE Healthcare; Vingmed Ultrasound, Horten, Norway) equipped with an M5S probe (frequency range: 1.5-4.6 MHz) and a 4V probe (frequency range: 1.5-4.0 MHz). Images were imported into and were selected for analysis using the EchoPAC203 software (GE Healthcare). The analysis mode was selected, followed by the volume and 4D Auto LAQ submodes. Following that, the sample point was positioned in the center of the mitral orifice in each of the three planes. The review function was used to acquire the LA parameters measured by 4D Auto LAQ, including volume and strain parameters. The maximum left atrial volume (LAVmax) and minimal left atrial volume (LAVmin) were significantly higher in the patient group (38.91 ± 9.72 vs. 46.31 ± 10.22, 17.75 ± 4.52 vs. 23.10 ± 7.13, respectively, all p values <.001). On the other hand left atrial reservoir longitudinal strain (LASr), conduit longitudinal strain (LAScd), contraction longitudinal strain (LASct), reservoir circumferential strain (LASr-c), conduit circumferential strain (LAScd-c), and contraction circumferential strain (LASct-c) were significantly lower in patient group (26.64 ± 5.64 vs.19.16 ± 4.58, -19.53 ± 3.72 vs. -11.28 ± 3.47, -10.34 ± 1.56 vs. -4.59 ± 1.49, 30.72 ± 4.04 vs. 19.31 ± 2.60, -19.91 ± 1.78 vs. -13.38 ± 2.85, -15.89 ± 6.37 vs. -9.24 ± 1.63, respectively, all p values <.001). The present study found that premature ventricular complexes can lead to atrial remodeling as well as ventricular remodeling in patients with PVC and 4D LAQ technology can quantitatively examine left atrial function and determine these alterations early.

Evaluation of left ventricular function with left atrio-ventricular longitudinal strain in patients with lymphoma underwent anthracycline therapy

Objective: To analyze the value of 3-dimensional speckle tracking echocardiograghy (3D-STE) derived strain parameters on the detection of subclinical myocardial deformation alterations in patients with lymphoma treated with anthracycline agents. Methods: This study was a retrospective study. A total of 37 patients with newly diagnosed diffuse large B cell non-Hodgkin lymphoma between December 2012 and December 2014 in Cancer Center, Fudan university were included. 3D-STE strain measurements were performed at baseline (T0),after the completion of two therapy circles (T1) and at the end of anthracycline regimen chemotherapy (Te). Echocardiography images were analyzed on the TTA workstation, and the indexes included left atrial minimum volume (LAVmin), left atrial emptying index (LAEF), left atrial active emptying index (LAAEF), as well as the left ventricular global longitudinal strain (LVGLS), left ventricular global circumferential strain (LVGCS), left atrial global longitudinal strain (LAGLS). The overall left atrioventricular longitudinal strain (LAVGLS) was calculated, which was the sum of the absolute values of LVGLS and LAGLS. The changes of left ventricular strain indexes measured by 3D-STE at different time points of patients were evaluated. Results: Thirty-seven patients with DLBCL, aged (48.3±12.1)years, including 23 males (63.9%), were enrolled. Compared with baseline, LVGLS (T1: (-18.63±4.73)% vs. (-22.13±4.40)%, P=0.001; Te:(-18.26±4.64)% vs. (-22.13±4.40)%, P<0.001), LAGLS (T1: (20.41±5.56)% vs. (23.98±5.59)%, P=0.003; Te: (17.60±3.96)% vs. (23.98±5.59)%, P<0.001) and LAVGLS (T1: (39.05±7.60)% vs. (46.11±7.77)%, P<0.001; Te: (40.34±8.55)% vs. (46.11±7.77)%, P<0.001) were all deteriorated at the T1 and Te. While LVGCS ((-21.98±5.82)% vs. (-26.15±7.51)%, P=0.010), LAVmin ((23.93±7.29)ml vs. (20.33±7.03)ml, P=0.029), LAEF ((28.94±11.16)% vs. (35.79±11.12)%, P=0.002) and LAAEF ((11.93±10.00)% vs. (18.10±9.96)%, P=0.013) were decreased only until Te. Conclusions: 3D-STE strain measurements could detect early myocaridial function alteration in patients receiving anthracycline regimen chemotherapy, thus may provide a novel approach to monitor anthracycline caused myocardial toxicity.

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.

Abstract 14663: The Impact of Continuous Positive Airway Pressure for Sleep Apnea on Left Atrial Dilatation in Patients Receiving Catheter Ablation of Atrial Fibrillation

Background Sleep apnea (SA) and left atrial dilatation (LA) are both risk factors for an arrhythmia recurrence after catheter ablation (CA) of atrial fibrillation (AF). Negative intrathoracic pressure fluctuations during an obstructive apnea episode may cause the left atrium to distend and stretch its wall. However, the impact of continuous positive airway pressure (CPAP) for SA on the reverse LA remodeling has not been elucidated. Methods This study was conducted under a retrospective, single-center, observational design. Data was derived from screening tests for sleep apnea, which were routinely performed in patients scheduled to receive CA of AF in our institution. The severity of the sleep apnea was evaluated by the apnea-hypopnea index (AHI). After excluding patients who were already diagnosed with sleep apnea, we enrolled 1232 consecutive patients who underwent multidetector computed tomography (MDCT) both before and 3-months after the CA of AF. The left atrial dilatation and volume reduction were evaluated by the left atrial minimum volume (LA min V) using 256-slice MDCT. Results The age was 65±11 years, 27.8% were females, and 46.0% had non-paroxysmal AF. The mean AHI was 20.2±15.2 and LA min V 79.1± 37.8ml (r=0.31, p&lt;0.0001) before CA. LA dilatation was defined as an LA min V≥79.1ml. After an adjustment by an advanced age (≥65 years), non-paroxysmal AF, male sex, obesity, hypertension, diabetes, and congestive heart failure, SA (AHI≥5) was a significant predictor of LA dilatation before CA (odds ratio 2.83, 95% confidence interval 1.55-5.16, p=0.0007). After CA, 206 out of 1092 patients (18.9%) with SA started CPAP. SA patients with CPAPs had a greater LA min V reduction rate on the postprocedural CT than those without CPAP (26.2% vs. 20.5%, p=0.013). Conclusion Among the patients scheduled to receive catheter ablation of AF, SA was independently associated with left atrial dilatation. Patients who started CPAP treatment for SA had greater LA reverse remodeling at 3 months after the CA.

Abstract 12425: The Interplay Between Left Atrial and Mitral Valvular Remodeling in Subtypes of Mitral Regurgitation

Background: The interaction between left atrial (LA) mechanics and mitral valve remodeling patterns in patients with mitral regurgitation (MR) is poorly described. Objectives: To assess three-dimensional (3D) LA volumes and strain in relation to 3D mitral valve morphology in patients with degenerative vs. functional MR. Methods: Patients included in the 3D-PRIME (3D Echocardiography and Cardiovascular Prognosis in Mitral Regurgitation) study at our heart valve clinic between 2020-2022 and with moderate or severe MR by combined transthoracic/transesophageal assessment were examined. LA remodeling was assessed by 3D maximum and minimum LA volume, reservoir strain (LASr) and contraction strain (LASct). Mitral valve annulus area, anterior and posterior leaflet length and area, tenting volumes and non-planar angle were measured using dedicated 3D mitral valve software. Results: 100 patients with moderate or severe MR were included. Patients with atrial functional MR (n=26) were older, more often women and had higher heart rate compared to degenerative MR (n=54) and ventricular functional MR (n=20) (p &lt;0.05). They also had larger LA volumes and severely impaired LASr and LASct despite smaller MR regurgitation volumes compared to MR by other mechanisms (Figure). Mitral annulus area was comparable between groups, but anterior mitral leaflet was higher, with larger area and the non-planar angle wider in functional MRs (p &lt;0.05). In multivariable analysis, low LASr (below median) was associated with larger LA volume, and higher anterior mitral leaflet height independent of age, sex, heart rate, left ventricular global longitudinal strain, and right ventricular stroke volume (Nagelkerke R 2 0.67, p &lt;0.01). In a similar model, low LASct was only associated with larger LA volumes. Conclusions: Patients with atrial functional MR have large LAs with severely impaired LA function and a specific mitral valve remodeling pattern at lower MR regurgitation volumes.

Abstract 13977: The Impact of Left Atrial Functional Changes on Clinical Outcomes Following Transcatheter Aortic Valve Replacement

Background: In patients with aortic stenosis (AS) and preserved left ventricular (LV) function, pre-intervention left atrial (LA) enlargement is common and predicts adverse events. Changes in LA function are appropriate markers of LV response to AS but have not been well explored in patients undergoing TAVI. The objectives of the current study were to evaluate changes in LA function following TAVI and their impact upon clinical outcomes. Methods: A total of 313 consecutive patients undergoing TAVI were included. There were 160 (51%) paired echocardiographic datasets with a median time of 1 (range 0-57) days pre-TAVI and a median time of 120 (1.2-810) days post-TAVI. All studies were evaluated for LA maximum volume index (LAVI max ), LA minimum volume index (LAVI min ), total emptying volume (LAEV), total emptying fraction (LAEF) and expansion index (LAEI). The pre-defined endpoints were cardiac-related hospitalization and all-cause death. Results: During a mean follow-up of 18 (±9.7) months, there were 58 deaths (18.5%) and 35 (11.2%) hospitalizations for heart failure, whereas 9 (2.9%) patients continued to report symptoms (NYHA 3). The prevalence of atrial fibrillation was 16.3% and coronary artery disease 52.7%. In a multivariate cox regression analysis, lower body surface area (HR 3.79; 95% CI 1.07-13.33, p=0.038), higher serum creatinine (HR 1.004; 95% CI 1.002-1.006, p&lt;0.001) and LV ejection fraction (EF) &lt;50% (HR 1.94; 95% CI 1.08-3.48, p=0.027) were predictors of all-cause mortality, independent of age, aortic valve area, the presence of coronary artery disease and time from index echocardiography to TAVI procedure. All LA function parameters demonstrated an improvement following TAVI (Fig. 1). In univariate cox regression analyses, baseline LA functional parameters were not associated with all-cause mortality alone or a composite of all-cause mortality and cardiac related hospitalization. Conclusions: In patients undergoing TAVI, lower body surface area, higher serum creatinine and LVEF &lt;50% were independent predictors of all-cause mortality. TAVI led to successful reverse LA functional and structural remodeling and LV functional recovery. However, pre-TAVI LA functional and structural parameters were not predictors of survival.

Left Atrial Structural and Functional Response in Kidney Transplant Recipients Treated With Mesenchymal Stromal Cell Therapy and Early Tacrolimus Withdrawal

Autologous bone marrow-derived mesenchymal stromal cell (MSC) therapy and withdrawal of calcineurin inhibitors (CNIs) has been shown to improve systemic blood pressure control and left ventricular hypertrophy regression in kidney transplant recipients. In the current subanalysis, we aimed to evaluate the impact of this novel immunosuppressive regimen on the longitudinal changes of left atrial (LA) structure and function after kidney transplantation. Kidney transplant recipients randomized to MSC therapy-infused at weeks 6 and 7 after transplantation, with complete discontinuation at week 8 of tacrolimus (MSC group)-or standard tacrolimus dose (control group) were evaluated with transthoracic echocardiography at weeks 4 and 24 after kidney transplantation. The changes in echocardiographic parameters were compared between the randomization arms using an analysis of covariance model adjusted for baseline variable. Fifty-four participants (MSC therapy=27; tacrolimus therapy=27) were included. There was no significant interaction between the allocated treatment and the changes of indexed maximal LA volume (LAVImax) over the study period. Conversely, between 4 and 24weeks post-transplantation, an increase in indexed minimal LA volume (LAVImin) was observed in control subjects, while it remained unchanged in the MSC group, leading to a significant difference between groups (P=.021). Additionally, patients treated with MSC therapy showed a benefit in LA function, assessed by a significant interaction between changes in LA emptying fraction and LA reservoir strain and the randomization arm (P=.012 and P=.027, respectively). The combination of MSC therapy and CNIs withdrawal prevents progressive LA dilation and dysfunction in the first 6months after kidney transplantation. LAVImin and LA reservoir strain may be more sensitive markers of LA reverse remodeling, compared with LAVImax.

Evaluation of Atrial Electromechanical Delay and Left Atrial Phasic Function in Individuals with Electrocardiographic Early Repolarization Pattern.

Atrial electromechanical delay (EMD) and left atrial (LA) phasic function have been demonstrated to be predictors for the development of atrial fibrillation (AF). In the present study, we aimed to evaluate atrial EMD and LA phasic function in individuals with electrocardiographic early repolarization pattern (ERP). Eighty consecutive individuals with ERP and 40 age- and gender-matched control subjects without ERP were compared in this cross-sectional study. Atrial electromechanical coupling (Pa') was measured from lateral mitral annulus (Pa'lateral), septal mitral annulus (Pa'septal), and lateral tricuspid annulus (Pa'tricuspid) using tissue Doppler echocardiography to calculate intra- and inter-atrial EMD. LA maximal volume, LA minimal volume, and LA volume before atrial contraction were calculated using the biplane area-length method to assess LA phasic function. LA diameter, LA volume index, Pa'lateral, Pa'septal, Pa'tricuspid electrical activity and intra-left atrial EMD were significantly increased in the ERP patients. Mitral lateral, septal, tricuspid lateral annular tissue Doppler s' and e' waves were significantly decreased in the ERP patients. There were no significant difference between the groups in terms of interatrial EMD, intra-right atrial EMD, LA total emptying volume and LA total emptying fraction indicating LA reservoir function, LA passive emptying volume and LA passive emptying fraction indicating LA conduit function, LA active emptying volume and LA active emptying fraction indicating LA pump function. Left atrial EMD parameters are affected in individuals with ERP, but LA phasic functions are not affected. Further prospective studies are needed to clarify whether individuals with ERP have an increased susceptibility to AF.