Left Atrial Appendage Dysfunction Research Articles

Does Left Atrial Appendage Dysfunction Predict Recurrent Atrial Fibrillation Post Radiofrequency Ablation? And, If So, Why?

Does Left Atrial Appendage Dysfunction Predict Recurrent Atrial Fibrillation Post Radiofrequency Ablation? And, If So, Why?

Comparison of left atrial and left atrial appendage mechanics in patients with ischaemic strokes of different aetiologies

Abstract Background Left atrial (LA) and left atrial appendage (LAA) mechanical dysfunction account for an increase in cardioembolic stroke risk in atrial fibrillation (AF), and more recently in individuals in sinus rhythm (SR). However, the exact contribution of LA and LAA to the pathogenesis of thromboembolic events is not fully understood. Here, we aimed to assess the alterations of LA and LAA mechanics in different stroke subtypes. Methods We recruited three groups of participants: patients with paroxysmal or persistent AF with a history of stroke (AF-stroke, n=69,respectively), individuals in SR with no history of AF but with acute ischaemic stroke(non-AF stroke,n=46); individuals with no history of AF or stroke(control group,n=17). Patients with AF were further categorized into sinus rhythm group (AF-stroke-SR,n=24) and AF rhythm group(AF-stroke-AF, n=45) according to the rhythm at the time of echocardiography. Using speckle-tracking echocardiography, global longitudinal strain (GLS) and mechanical dispersion (MD) of LA and LAA were measured in all patients. Mechanical dispersion was defined as the standard deviation of the time to peak of the regional strain corrected by R-R interval. Results Patients with AF-stroke demonstrated prominently impaired LA and LAA mechanics(LA GLS: 20±6%(AF-stroke-SR),11±4%(AF-stroke-AF); LA MD: 9±3%,11±3%; LAA GLS: 15±3%,11±4% ; LAA MD: 11±4%,12±3% ,respectively) compare with those with non-AF stroke and controls (LA GLS:35±8%, 41±11%;LA MD,6±2%, 4±2%; LAA GLS:21±5%, 23±7%; LAA MD:8±4%, 7±3%,respectively) (all p<0.01). Interestingly, LA and LAA mechanical function was not significantly different between patients with non-AF strokes and the control group. In multivariable analysis, only AF-strokes were independently associated with LA and LAA GLS after adjusting for age and comorbidities (both P<0.01). Conclusions Mechanical dysfunction of LA and LAA might play a greater role in pathogenesis of strokes related to AF rather than non-AF strokes.

Left atrial strain time integral evaluated by two-dimensional speckle tracking predicts left atrial appendage dysfunction in patients with acute ischemic stroke.

Cardioembolic stroke is a serious disease with poor prognosis, whose main embolic source is the left atrial appendage (LAA). Left atrial (LA) strain evaluated by the two-dimensional (2D) speckle tracking technique has been proposed. However, the commonly used peak LA strain reflects only LA reservoir function. The LA strain also includes indicators of the other LA functions, such as booster pump function, which reflects active contraction of the LA. This study aimed to investigate whether a newly developed parameter, the left atrial strain time integral (LASTI), can evaluate LAA dysfunction more accurately in patients with acute stroke. We measured LA strain using a 2D speckle tracking method in 168 patients with acute stroke and 20 age-matched control subjects. LASTI was calculated as the area under the LA strain curve in one cardiac cycle. LAA dysfunction was defined as LAA thrombus and/or severe spontaneous echo contrast by transesophageal echocardiography. LASTI was significantly lower in patients with LAA dysfunction than those without. LASTI was a better correlation with LAA blood flow velocity measured by transesophageal echocardiography than peak LA strain. Multivariate logistic regression analysis showed that LASTI was an independent predictor of LAA dysfunction after adjustment for conventional risk factors. LASTI can be a feasible parameter for predicting LAA dysfunction in patients with acute stroke.

Comparison of the Appendicular Emptying Velocity of Left Atrium in patient with moderate versus severe chronic rheumatic mitral stenosis measured by pulsed wave Doppler in Transesophageal echocardiography

Background: Left atrial appendage (LAA) is considered the “most lethal human appendage” as it causes significant mortality and morbidity in chronic rheumatic mitral stenosis patients due to cardiogenic cerebral infract. Presence of LAA dysfunction has been shown to be a strong predictor of thrombus formation and the risk of embolic event, even if no clot is found at the time of initial examination. LAA emptying velocity are measured by trans esophageal echocardiography (TEE) represent as a surrogate marker for left atrial(LA) function .LAA emptying velocities (contraction velocity) < 20cm/s are associated with risk of spontaneous echo contrast(SEC), LAA thrombus, and subsequent cardio embolic events. So early detection of low emptying velocity without SEC or LA thrombus can reduce mortality & morbidity related to cardio embolic stroke and also helps in further management procedure like cardio version etc. So we will compare LAA emptying velocity moderate versus severechronic rheumatic mitral stenosis patients in our population for further attention.
 Objective: To assess emptying velocity of LAA in patient with moderate versus severe chronic rheumatic mitral stenosis, from a Bangladesh health service perspective.
 Method: This was a cross sectional study which was conducted in UCC, BSMMU during the period of from February 2019 to September 2019 in Echo lab .
 Study Procedure: We were enrolled 33 CRHD with MS (moderate to severe) patients who underwent TEE and met inclusion & exclusion criteria. The purpose of the study was explained to each subject & informed written consent was obtained. After getting consent relevant history, physical examination and preprocedural investigation was obtained in predesigned structured data collection sheet. TEE was done with Vivid E9® machine. Pulse wave Doppler was position at the tip of the LAA and then emptying velocity of LAA moderate and severe were compared.
 Outcome measure: Among 33 patients, 3 patients were excluded due to outlier and inadequate data.. In chronic rheumatic mitral stenosis in moderate versus severe cases average LAA emptying velocities were significantly higher moderate CRHD with MS compare to severe CRHD with MS,(26.57±4.91;31.12±5.04), P=0.018.
 Conclusion:Appendicular emptying velocity of LAA significantly lower in severe CRHD with MS compare to moderate CRHD with MS and it has temporal relation with MS severity. It can be used as a reliable, simple and sami-invasive tool to early predict severity and prevent complication in CRHD with MS as well as for prophylactic measured taken.
 University Heart Journal 2022; 18(2): 73-79

NO CLOT, NO PROBLEM? NOT EXACTLY

NO CLOT, NO PROBLEM? NOT EXACTLY

Transesophageal Echocardiography Following Left Atrial Appendage Electrical Isolation: Diagnostic Pitfalls and Clinical Implications.

Following left atrial appendage (LAA) electrical isolation, the decision on whether to continue oral anticoagulation after successful atrial fibrillation ablation is based on the study of its mechanical function on transesophageal echocardiography (TEE). In this cohort, LAA contraction is absent and the incorrect interpretation of emptying flow velocities can lead to unwanted clinical sequelae. One hundred and sixty consecutive TEE exams performed to evaluate the LAA mechanical function following its electrical isolation were reviewed by an experienced operator blinded to the original diagnosis of LAA dysfunction. The rate of diagnostic discrepancy in the assessment LAA dysfunction and its clinical implications were evaluated. Diagnostic discrepancy with misclassification of the LAA mechanical function occurred 36% (58/160) of TEE exams. In most cases (57/58), such discrepancy was observed in the setting of an incorrect original diagnosis of a normal LAA mechanical function despite absent/reduced or inconsistent LAA contraction. This main source of this wrong diagnosis was the wrong interpretation of passive LAA flows (34/57; 60%), followed by failure to identify dissociated firing (15/57; 26%). In rare cases (8/57; 14%), velocities of surrounding structures were interpreted as LAA flow due to misplacement of the pulsed-wave Doppler sample volume. Following LAA isolation, the proportion of patients who experienced a cerebrovascular event while off oral anticoagulation due to the misclassification of their LAA mechanical function was 70% (7/10 [95% CI, 40%-89%]). Underdiagnosis of LAA mechanical dysfunction is common in TEEs performed following LAA electrical isolation, and it is associated with an increased risk of cerebrovascular events owing to oral anticoagulation discontinuation despite absent/reduced LAA contraction. Careful review of the TEE exam by an operator with specific expertise in LAA imaging and familiar with the functional implications of LAA isolation is necessary before interrupting oral anticoagulation in this cohort.

Evaluating left atrial appendage function in a subtype of non-valvular atrial fibrillation using transesophageal echocardiography combined with two-dimensional speckle tracking

The use of transesophageal echocardiography (TEE) is a clinically feasible method for quantitative analysis of left atrial appendage (LAA) function. LAA dysfunction is closely associated with atrial fibrillation (AF)-related stroke. However, there are few studies on the changes in LAA function in patients with different types of AF. This study aimed to observe changes in LAA systolic motion and function in patients with different types of AF by using speckle-tracking echocardiography (STE). A retrospective study of 216 patients with non-valvular AF was conducted. The LAA was divided into three parts: the basal segment (B), middle segment (M), and top segment (A). Speck -racking technology was used to measure and record the forward strain values of the basal segment (B), middle segment (M), and top segment (A) of the LAA, and the peak positive strain dispersion of the LAA was calculated. The left atrial appendage mechanical dispersion (LAAMD) was defined as the standard deviation (SD) of the peak positive strain at each segment of the R-R interval. Partial speckle-tracking parameters of the LAA showed statistical significance between the two groups. The peak strain on the top segment of the LAA was reduced in the persistent atrial fibrillation (per-AF) group compared to the paroxysmal atrial fibrillation (par-AF) group [11.87 (6.47-20.12) vs. 16.02 (9.76-24.50); 12.66 (6.66-21.22) vs. 20.16 (14.16-30.56); both P<0.01]. In the group with lower LAAMD, the proportion of patients with persistent AF (per-AF) was higher (66.3% vs. 33.7%; P<0.001), the left atrial dilatation was more significant (45.80±5.656 vs. 42.85±4.867; P<0.001), the LAA filling velocity and LAA empty velocity were lower (42.35±20.354 vs. 51.0±20.599; 38.71±24.39 vs. 51.62±21.282; both P<0.001), the LAA ejection fraction was significantly lower (52.16±25.538 vs. 70.85±20.741; P=0.000), and the peak positive strains of the M and A of the LAA were lower than those in the higher LAAMD group. The deformability of the LAA is decreased diffusely in per-AF, especially in the A of the LAA. Compliance with LAA was worse in patients with per-AF than in those with par-AF.

Impact of COVID-19 Pandemic and Lockdown on the Management of Upper Gastrointestinal Relationship between Mitral Annular Velocities and Left Atrial Appendage Emptying Velocity

Background: Mitral stenosis (MS) is a prevalent kind of valvular heart disease. Thromboembolism is one of the most severe complications, particularly when it is accompanied with atrial fibrillation (AF). When associated with Left atrial appendage (LAA) dysfunction, patients with sinus rhythm (SR) are also at risk for this condition. In mitral stenosis, LAA dysfunction is an independent predictor of thromboembolism. The aim of the study was to see if there is an association between mitral annular velocities measured with Doppler tissue imaging (DTI) and LAA function measured with transesophageal echocardiography (TEE), and to see if annular velocities can predict the presence of an inactive LAA in MS. Methods: This was an observational study carried out by the department of cardiology of the National Institute of Cardiovascular Diseases (NICVD). From January 2006 to December 2007, 60 MS patients were evaluated using transthoracic echocardiography and transesophageal echocardiography. The systolic (S-wave) and diastolic (Em- and Am-waves) annular velocities were measured. Inactive LAA was defined as a velocity of &lt;25 cm/sec for LAA emptying. Patients were divided into three groups. Group A (I) (n = 18): Sinus rhythm (SR) and LAA emptying velocity ≥25 cm/sec, group A (II) (n =22): SR and LAA emptying velocity &lt;25cm/sec and group B (n = 20): atrial fibrillation. Results: Thrombus was found in 14 patients, and spontaneous echo contrast (SEC) was found in 43. From group A to group B, S-wave and peak LAA emptying velocities decreased while SEC frequency and density increased. There was a positive correlation between LAA emptying versus S-wave &amp; Am wave velocity (p&lt;0.001, r= 0.708 and p&lt;0.001, r=0.495, respectively). Only S-wave was found to be an independent predictor of inactive LAA in multivariate regression analysis (p = 0.001, odds ratio = 0.133, 95%ci =0.032-0.556). The cutoff value of S-wave in patients with SR for predicting the presence of inactive LAA was.........

Filling defects in the left atrial appendage restricted to the early phase of cardiac computed tomography as a potential risk of left atrial appendage dysfunction

BackgroundFilling defects within the left atrial appendage (LAA) restricted to the early phase of computed tomography (CT) are not highly specific to the presence of thrombosis. The true significance of LAA early filling defects without thrombus remains uncertain. We evaluated the predictors of LAA early filling defects on echocardiography and cardiac CT findings in patients with atrial fibrillation (AF). MethodsCardiac CT findings of 641 patients with AF who underwent transesophageal echocardiography prior to pulmonary vein isolation from 6 January 2013 to 16 December 2019 at our institution were retrospectively analyzed. We investigated potential predictors of LAA early filling defects and computed the receiver operator characteristics, choosing a threshold value at which the likelihood of LAA early filling defects could be predicted. ResultsEarly filling defects within the LAA correlated significantly with a history of persistent AF [p = 0.014; odds ratio (OR), 2.36; 95% confidence interval (CI), 1.19–4.66), low left ventricular ejection fraction (p = 0.009; OR, 2.62; 95% CI, 1.28–5.38), diminished LAA flow velocity (p < 0.001; OR, 0.97; 95% CI, 0.96–0.99) below 45.3 cm/s (sensitivity, 63.6%; specificity, 72.4%), and increased indexed LAA volume (p = 0.001; OR, 1.18; 95% CI, 1.07–1.30) ≥7.64 cm3/m2 (sensitivity, 70.5%; specificity, 69.0%). ConclusionEarly filling defects within the LAA on cardiac CT were associated with LAA function including risk factors for thrombus development, which could lead to noninvasive estimation of LAA function and additional information for risk stratification of thromboembolic events in patients with AF.

Prone-position computed tomography in the late phase for detecting intracardiac thrombi in the left atrial appendage before catheter ablation for atrial fibrillation.

BackgroundContrast computed tomography (CT) is a useful tool for the detection of intracardiac thrombi. We aimed to assess the accuracy of the late‐phase prone‐position contrast CT (late‐pCT) for thrombus detection in patients with persistent or long‐standing persistent atrial fibrillation (AF).MethodsEarly and late‐phase pCT were performed in 300 patients with persistent or long‐standing AF. If late‐pCT did not show an intracardiac contrast defect (CD), catheter ablation (CA) was performed. Immediately before CA, intracardiac echocardiography (ICE) from the left atrium was performed to confirm thrombus absence and the estimation of the blood velocity of the left atrial appendage (LAA). For patients with CDs on late‐pCT, CA performance was delayed, and late‐pCT was performed again after several months following oral anticoagulant alterations or dosage increases.ResultsOf the 40 patients who exhibited CDs in the early phase of pCT, six showed persistent CDs on late‐pCT. In the remaining 294 patients without CDs on late‐pCT, the absence of a thrombus was confirmed by ICE during CA. In all six patients with CD‐positivity on late‐pCT, the CDs vanished under the same CT conditions after subsequent anticoagulation therapy, and CA was successfully performed. Furthermore, the presence of residual contrast medium in the LAA on late‐pCT suggested a decreased blood velocity in the LAA ( ≤ 15 cm/s) (sensitivity = 0.900 and specificity = 0.621).ConclusionsLate‐pCT is a valuable tool for the assessment of intracardiac thrombi and LAA dysfunction in patients with persistent or long‐standing persistent AF before CA.

Left Atrial Appendage Flow Velocity and Multiple Infarcts in Cryptogenic Stroke

Background: To validate the hypothesis that cryptogenic stroke with multiple infarcts included embolic stroke due to left atrial appendage (LAA) dysfunction, the present retrospective observational study was aimed to clarify the association between LAA flow velocity (LAA-FV) and multiple infarcts in patients with cryptogenic stroke. Methods: From consecutive patients with cryptogenic stroke admitted to our hospital within 7 days after onset, patients without brain magnetic resonance imaging (MRI) on admission or without transesophageal echocardiography (TEE) during acute hospitalization were excluded, and the remaining patients were enrolled. Multiplicity of fresh infarcts was assessed using diffusion-weighted images from brain MRI. LAA-FV was defined as LAA peak emptying flow velocity on TEE. Results: Of 786 enrolled patients, 522 patients (66%) had a single infarct, and the remaining 264 patients (34%) had multiple infarcts. The percentage of multiple infarcts decreased with increasing quartiles of LAA-FV (p for trend <0.001). The adjusted odds ratio for multiple infarcts decreased with increasing quartiles of LAA-FV (adjusted odds ratio in the fourth quartile, 0.39; 95% confidence interval, 0.25–0.60; compared with the first quartile). LAA-FV as a continuous variable was negatively associated with multiple infarcts (adjusted odds ratio per 10 cm/s, 0.87; 95% confidence interval, 0.81–0.92). Conclusions: Reduced LAA-FV on TEE was associated with multiple infarcts in patients with cryptogenic stroke. The present findings indicate that cryptogenic stroke with multiple infarcts includes embolic stroke due to LAA dysfunction.

Comparison of left atrial and left atrial appendage mechanics in the risk stratification of stroke in patients with atrial fibrillation

BackgroundLeft atrial (LA) and left atrial appendage (LAA) dysfunction has been demonstrated to contribute to atrial fibrillation (AF)-related stroke. However, usefulness of LA and LAA mechanics has not been fully compared. We sought to investigate the association of LA and LAA mechanics with stroke and to compare their diagnostic values in the risk stratification of stroke in patients with nonvalvular AF.MethodsA total of 208 consecutive patients with AF (63.58 ± 10.37 years, 63.9% male,57.7% persistent AF) who underwent echocardiography before catheter ablation were prospectively enrolled. Speckle-tracking was used to measure LA and LAA global longitudinal strain (GLS). LA and LAA mechanical dispersions (MD) were defined as the standard deviation (SD) of time to peak positive strain corrected by the R-R interval.ResultsPatients with prior stroke/ transient ischemic attack (TIA) (n = 31) had significantly higher LA and LAA MD than those without (n = 177) (11.56 ± 4.38% vs. 8.43 ± 3.44%, 15.15 ± 5.46% vs. 10.94 ± 4.40%, both P < 0.01). In multivariable analysis, LA and LAA MD were independently associated with stroke/TIA (odds ratio, 1.18–1.29, 1.19–1.22, respectively, both P < 0.01), providing incremental values over clinical and standard echocardiographic parameters. In a subgroup analysis, LA MD was more useful than LAA MD in patients with normal LA volumes, while LAA MD was superior to LA MD in patients with LA enlargement.ConclusionsHigher LA and LAA mechanical dispersion are independently associated with stroke/TIA in AF patients and had incremental values over clinical and conventional echocardiographic parameters. What’s more, priorities of dispersion assessment are different depending on patients’ LA size.

Evaluating the novel parameters for assessing the LAA function and thrombus formation with nonvalvular atrial fibrillation.

The dysfunction of left atrial appendage (LAA) is prone to form thrombus when atrial fibrillation (AF) sustained more than 48 h. Traditional 2D-TEE (transesophageal echocardiography) can not accurate evaluate the function of LAA. The purpose of this study is to analyze the relationship of LAA function parameters and thrombus formation in patients with non-valvular atrial fibrillation (NVAF) by real-time three-dimensional transesophageal echocardiography (RT-3D-TEE). High risk patients can be identified according to the characteristics of ultrasonic index in patients with left atrial appendage thrombosis, which has important clinical value and significance in the risk assessment, guiding treatment and judging prognosis. We examined the relationship between the echocardiographic parameters of LAA function and the incidence of thrombus in 102 NVAF patients. They underwent RT-3D-TEE and left atrial appendage thrombus (LAAT)/severe spontaneous echocardiographic contrast (SSEC) was found in 67 patients (thrombus group) but absent in the remaining 35 patients (non-thrombus group). After measured by QLAB software, the LAA functional parameters were significantly associated with LAAT/SEC formation. Univariate analysis indicated that AF time, LAD, LVEF, LAA-OAmax, LAAVmax, LAAVI and LAAEF demonstrated a positive association (P < 0.05). However, logistic regression analysis identified that AF time (OR:1.73, P < 0.05)、LAAEF (OR:4.09, P < 0.01)and LAAVI (OR:3.28, P < 0.01) were independent predictors of LAAT/SSEC. In patients with nonvalvular atrial fibrillation, echocardiographic parameters of LAA function are significantly associated with LAAT/SSEC.

P1360Association between left atrial appendage dysfunction and thromboembolic risk in nonvalvular atrial fibrillation

Abstract Background/Introduction: Atrial fibrillation (AF) is associated with higher risk for thromboembolism , and the discriminative ability of the widely used CHA2DS2-VASc scores for risk stratification is modest. Although the presence of thrombus in the LAA is the most powerful predictors for thromboembolic risk, they are often absent in patients with AF and prior stroke. AF may be related to myocardial fibrosis, and even though left atrial fibrosis is associated with mechanical dispersion, this phenomenon is not well studied in LAA. We hypothesized that detection of LAA dysfunction and mechanical dispersion using strain echocardiography is useful in the identification of cardiac thromboembolism. Purpose The aim of this study was to determine the association of LAA mechanics assessed using strain analysis with previous thromboembolic events in patients with nonvalvular AF and to assess the potential incremental significance of LAA mechanical dispersion over the traditional risk stratification scheme. Methods A group of 116 patients with AF referred for TEE was prospectively analyzed. LAA strain and mechanical dispersion in parallel with other conventional TEE parameters were analyzed in terms of their association with previous embolic stroke and peripheral embolization. Results Patients with embolic events had a higher mean CHA2DS2-VASc score, higher incidence of LAA dense SEC or thrombi, and other clinical data were comparable. Patients with embolic events had greater impairment in the LA standard parameters, and lower global and regional LAA longitudinal strain than those of the controls. LAA MD was significantly higher in patients with embolization than in those without it (18.91 ± 7.19 %vs 13.8 ± 5.54%; P &amp;lt; .001). In ROC analysis, cut-off values for LAA MD,LAEF, LAA GLS for the presence of dense SEC/ thrombus were &amp;gt;20.21 % (p = 0.0076), ≤31.11 % (p = 0.017), and ≤ 7.31 % (p = 0.014), respectively. LAA MD, LAEF, LAA thrombus and CHA2DS2-VASc scores were independently associated with the presence of thromboembolism in multivariate analyses, and LAA MD had additional significance over the CHA2DS2-VASc score. Conclusion LAA MD, LAA thrombi and LAEF had statistically significant meaning for the presence of prior embolism that was independent of the standard planimetric and volumetric measurements. What’s more, LAA MD had an incremental value over CHA2DS2-VASc score in risk stratification and warrants testing in a larger study. Abstract Figure. ROC curves for LAA parameters

Study of immediate and late effects of successful PTMC on left atrial appendage function in patients with severe rheumatic mitral stenosis IN SINUS rhythm

IntroductionSince its introduction in 1984, Percutaneous Transvenous Mitral Commissurotomy (PTMC) has become established as a safe and effective treatment for rheumatic Mitral Stenosis (MS).( Ben Farhat et al., 1998) 1 Chronic pressure and volume overload imposed by MS causes left atrial (LA) and Left Atrial Appendage (LAA) dysfunction. Risk of cerebrovascular accident (CVA) is increased approximately 17-fold in patients of MS in Atrial Fibrillation (AF) and is present even in patients of MS in sinus rhythm (SR). This study was undertaken to evaluate the effect of PTMC on LAA function by Trans-esophageal echocardiography (TEE) Doppler and Doppler Tissue Imaging (DTI). MethodsTotal 70 cases were enrolled in this study. Patients with symptomatic severe MS (Mitral Valve Area <1.5cm2), in SR, who underwent a successful PTMC during the period from May 2016 to May 2019 were selected. All the patients underwent Clinical examination, ECG, detailed TTE and TEE before, immediately after (within 24 h) & after 6 months of PTMC. ResultsThere was non significant improvement in Left Atrial appendage fractional area change {LAAAC (%)} immediately Post PTMC but there was significant improvement at 6 months Post PTMC. There was significant increase in LAA PW Doppler velocities (LAAEDE, LAALDE and LAAF velocity) immediately Post PTMC which got further improved significantly at 6 months of follow up. There was significant increase in LAA DTI velocities (ELAA, ALAA and SLAA velocity) immediately Post PTMC which got further improved significantly at 6 months of follow up. ConclusionPTMC improves left atrial appendage function in patients with mitral stenosis.

Left Atrial Strain as Evaluated by Two-Dimensional Speckle Tracking Predicts Left Atrial Appendage Dysfunction in Chinese Patients with Atrial Fibrillation.

Left atrial appendage (LAA) dysfunction identified by transesophageal echocardiography (TEE) is a powerful predictor of stroke in patients with atrial fibrillation (AF). The aim of our study is to assess if there is a correlation between the left atrial (LA) functional parameter and LAA dysfunction in the AF patients. This cross-sectional study included a total of 249 Chinese AF patients who did not have cardiac valvular diseases and were undergoing cardiac ablation. TEE was performed in all the patients who were categorized into two groups according to their left atrial appendage (LAA) function. A total of 120 of the 249 AF patients had LAA dysfunction. Univariate and multivariate logistic regression was conducted to assess the independent factors that correlated with the LAA dysfunction. Different predictive models for the LAA dysfunction were compared with the receiver operating characteristic (ROC) curve. The final ROC curve on the development and validation datasets was drawn based on the calculation of each area under the curves (AUC). Univariate and multivariate analysis showed that the peak left atrial strain (PLAS) was the most significant factor that correlated with the LAA dysfunction. PLAS did not show inferiority amongst all the models and revealed strong discrimination ability on both the development and validation datasets with AUC 0.818 and 0.817. Our study showed that a decrease in PLAS is independently associated with LAA dysfunction in the AF patients.

Study of Left Atrial Appendage Function in Patients of Severe Rheumatic Mitral Stenosis and Effect of Successful PTMC on SEC Grading

Background: Left Atrial Appendage (LAA) dysfunction is common in patients of Mitral stenosis (MS). In the present study we compared the LAA function amongst patients of severe rheumatic MS with particular reference to spontaneous echo contrast (SEC) and evaluated the effect of successful Percutaneous Transvenous Mitral Commissurotomy (PTMC) on SEC grading. Methods: It was a single centre prospective descriptive type of study. Total 75 cases were included during the study period from 2016 to 2020. Symptomatic patients with severe rheumatic mitral stenosis (MVA<1.5cm2) in sinus rhythm fulfilling the elective PTMC intervention criteria and those who had a successful intervention only were included. All the patients underwent Clinical examination, ECG, detailed TTE and TEE before, Immediately after (within 24hrs) & after 6 months of PTMC. Results: In the present study mean LAAAC% and LAA PW Doppler velocities were significantly less in patients of severe rheumatic Mitral Stenosis having SEC than patients without SEC, implying more severe LAA dysfunction in patients with SEC. LAA Tissue Doppler velocities were also less in patients with SEC compared to patients without SEC but it was statistically not significant. There was a significant negative correlation between SEC grading and LAAAC (%) and LAA PW Doppler velocities (LAAEDE Velocity, LAALDE Velocity and LAAF velocity), i.e. greater the degree of SEC lesser was the LAAAC (%), LAAEDE Velocity, LAALDE Velocity and LAAF velocity, suggesting more severe LAA dysfunction in patients with greater degree of SEC. There was also negative correlation between SEC grading and LAA Tissue Doppler velocities (ELAA Velocity, ALAA Velocity, SLAA Velocity) but it was statistically not significant. Successful PTMC resulted in significant decrease in SEC grading. Conclusion: Among the patients of severe rheumatic mitral stenosis, presence of SEC implies severe LAA dysfunction, greater the intensity of SEC, greater would be the severity of LAA dysfunction and successful PTMC results in improvement of SEC grading.

Sacubitril/Valsartan Improves Left Atrial and Left Atrial Appendage Function in Patients With Atrial Fibrillation and in Pressure Overload-Induced Mice.

LCZ696 (sacubitril/valsartan) is an angiotensin receptor-neprilysin inhibitor and has shown beneficial effects in patients with heart failure. However, whether LCZ696 protects against left atrial (LA) and LA appendage (LAA) dysfunction is still unclear. The present study aimed to assess the efficacy of LCZ696 for improving the function of LA and LAA. We performed both a retrospective study comparing LCZ696 with angiotensin receptor blockers (ARBs) to assess the efficacy of LCZ696 in patients with atrial fibrillation and an animal study in a mouse model with pressure overload. LA peak systolic strain, LAA emptying flow velocity, and LAA ejection fraction (LAAEF) were significantly increased in patients with LCZ696 as compared with ARBs (p = 0.024, p = 0.036, p = 0.026, respectively). Users of LCZ696 had a lower incidence of spontaneous echocardiography contrast (p = 0.040). Next, patients were divided into two groups (LAAEF ≤ 20% and > 20%). Administration of LCZ696 in patients with LAAEF > 20% was more frequent than LAAEF ≤ 20% (p = 0.032). Even after controlling for LAA dysfunction-related risk factors (age, atrial fibrillation type, old myocardial infarction, hypertension, congestive heart failure, and prior stroke or transient ischemic attack), use of LCZ696 remained significantly associated with reduced probability of LAAEF ≤ 20% [odds ratio = 0.011; 95% confidence interval (0.000–0.533), p = 0.023]. To further confirmed effect of LCZ696 in LA function, we constructed a post-transverse aortic constriction model in mice. Mice with LCZ696 treatment showed lower LA dimension and higher left ventricular ejection fraction and LAA emptying flow velocity as compared with mice with vehicle or valsartan treatment. Meanwhile, as compared with vehicle or valsartan, LCZ696 significantly decreased LA fibrosis in mice. In summary, we provide evidence that LCZ696 may be more effective in improving LA and LAA function than ARBs in both humans and mice, which suggests that LCZ696 might be evaluated as a direct therapeutic for atrial remodeling and AF.

P2462Left atrial appendage wall velocity evaluated by transthoracic echocardiography is a feasible parameter for predicting cardiac prognosis in patients with heart failure

Abstract Background It was reported that left atrial (LA) remodeling is occurred in patients with heart failure (HF), and increased LA volume index (LAVI) is a feasible predictor for poor prognosis of HF. It was reported that LA remodeling is associated with LA appendage (LAA) dysfunction. We previously reported that LAA wall motion velocity (LAWV) obtained by transthoracic echocardiography (TTE) can noninvasively evaluate LAA dysfunction. However, it remains to be determined whether LAWV is useful for predicting poor prognosis in patients with HF. Purpose We investigated whether LAA dysfunction assessed by LAWV is associated with poor prognosis in patients with HF. Methods We performed TTE at discharge in 217 consecutive patients who hospitalized for HF (126 males, 71±13 years) and prospectively followed them up. LAWV was measured using Doppler tissue imaging at the LAA tip from the parasternal short-axis view on TTE imaging. Results There were 86 patients with cardiac events including 14 cardiac deaths and 72 rehospitalizations for HF during a median follow-up period of 404 days (interquartile range 168–748 days). LAWV was significantly lower in patients with cardiac events than in those without. LAWV was significantly decreased with advancing left ventricular diastolic dysfunction grade. Kaplan-Meier analysis demonstrated that significantly higher cardiac event rate was observed in patients with low LAWV (log-rank test, P=0.004). Cox multivariate hazard analysis revealed that LAWV was an independent predictor for cardiac events after adjusting for confounding factors (hazard ratio 0.57, 95% confidence interval 0.40–0.82, P&lt;0.05). Further, we categorized the patients into 3 groups based on the median of LAWV and left atrial volume index (LAVI), and Kaplan-Meier analysis showed that patients with both low LAWV and high LAVI had the highest rate of cardiac events among 3 groups (log-rank test, P&lt;0.001; Figure). Figure 1 Conclusion LAWV may be a feasible parameter for predicting cardiac prognosis in patients with HF.

Left atrial remodeling index is a feasible predictor of poor prognosis in patients with acute ischemic stroke.

Left atrial (LA) functional remodeling as well as LA structural remodeling are associated with incident LA appendage (LAA) thrombus formation. This study aimed to elucidate whether combined assessment of LA functional and structural remodeling can predict LAA dysfunction and recurrent cerebrovascular events in patients with acute ischemic stroke. We performed transthoracic and transesophageal echocardiography in 196 patients within 7days after acute ischemic stroke. Peak systolic LA strain was evaluated using 2D speckle tracking imaging. We defined the ratio of LA peak systolic strain to LA volume index (LAVI) as the LA remodeling index (LARI). All patients were prospectively followed for recurrent cerebrovascular events. We divided patients into four groups according based on the LARI quartile. LAA dysfunction increased with decreasing LARI. In total, 52 recurrent cerebrovascular events were noted during the median follow-up period of 700days. Patients with recurrent cerebrovascular events had lower LARI than those without recurrent events (0.50 ± 0.45 vs. 1.10 ± 0.95, P < 0.001). Kaplan-Meier analysis showed that patients with lower LARI were more susceptible to recurrent cerebrovascular events than those with higher LARI. Multivariate Cox proportional hazard regression analysis showed that LARI was an independent predictor of recurrent cerebrovascular events after adjustment for confounding factors. Net reclassification index improved with the addition of LARI to basic predictors. LARI is a novel feasible parameter for LAA dysfunction and can predict recurrent cerebrovascular events in patients with acute ischemic stroke.