Dense Spontaneous Echo Contrast Research Articles

Radiomics prediction models of left atrial appendage hypercoagulability based on machine learning algorithms: an exploration about cardiac computed tomography angiography imaging.

Transesophageal echocardiography (TEE) is the standard method for diagnosing left atrial appendage (LAA) hypercoagulability in patients with atrial fibrillation (AF), which means LAA thrombus/sludge, dense spontaneous echo contrast and slow LAA blood flow velocity (< 0.25m/s). Based on machine learning algorithms, cardiac computed tomography angiography (CCTA) radiomics features were adopted to construct prediction models and explore a suitable approach for diagnosing LAA hypercoagulability and adjusting anticoagulation. This study included 652 patients with non-valvular AF. The univariate analysis were used to select meaningful clinical characteristics to predict LAA hypercoagulability. Then 3D Slicer software was adopted to extract radiomics features from CCTA imaging. The radiomics score was calculated using the least absolute shrinkage and selection operator logistic regression analysis to predict LAA hypercoagulability. We then combined clinical characteristics and radiomics scores to construct a nomogram model. Finally, we got prediction models based on machine learning algorithms and logistic regression separately. The area under the receiver operating characteristic curve of radiomics score was 0.8449 in the training set and 0.7998 in the validation set. The nomogram model had a concordance index of 0.838. The final machine-learning based prediction models had good performances (best f1 score = 0.85). Radiomics features of long maximum diameter and high uniformity of Hounsfield unit in left atrial were significant predictors of the hypercoagulable state in LAA, with better predictive efficacy than clinical characteristics. Our combined models based on machine learning were reliable for hypercoagulable state screening and anticoagulation adjustment.

Relationship of inflammatory indices with left atrial appendage thrombus or spontaneous echo contrast in patients with atrial fibrillation.

Inflammatory indices derived from complete blood tests have been reported to be associated with poor outcomes in patients with atrial fibrillation (AF). The data about the relationship between inflammatory indices and left atrial appendage thrombus (LAAT) or dense spontaneous echo contrast (SEC) are limited. To explore the value of inflammatory indices for predicting the presence of LAAT or dense SEC in nonvalvular AF patients. A total of 406 patients with nonvalvular AF who underwent transesophageal echocardiography were included and divided into two groups based on the presence (study group) or absence (control group) of LAAT or dense SEC. Inflammatory indices, including the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and lymphocyte-to-monocyte ratio (LMR), were calculated from complete blood analysis. The associations of inflammatory indices with LAAT/dense SEC were analyzed using logistic regression. LAAT and dense SEC were detected in 11 (2.7%) and 42 (10.3%) patients, respectively. The PLR only showed an association with LAAT/dense SEC in the univariate model. Elevated NLR (odds ratio [OR] = 1.48, 95% confidence interval [CI]: 1.11-1.98, P = 0.007) and reduced LMR (OR = 0.59, 95%CI: 0.41-0.83, P = 0.003) were found to be independent risk factors for the presence of LAAT/dense SEC. The areas under the NLR and LMR curves for predicting LAAT/dense SEC were 0.73 (95%CI: 0.66-0.80, P < 0.001) and 0.73 (95%CI: 0.65-0.81, P < 0.001), respectively, while the cutoff values were 2.8 (sensitivity: 69.8%; specificity: 64.0%) and 2.4 (sensitivity: 71.7%; specificity: 60.6%), respectively. Increased NLR and decreased LMR may predict LAAT/dense SEC in patients with nonvalvular AF.

Development and validation of a nomogram superior to CHADS2 and CHA2DS2-VASc models for predicting left atrial appendage dense spontaneous echo contrast/left atrial appendage thrombus.

Atrial fibrillation (AF) is one of the most frequently encountered arrhythmias in clinical practice, with stroke triggered by detachment of left atrial appendage thrombus (LAAT) after AF being its most critical complication. The purpose of this study was to construct a nomogram model for forecasting left atrial appendage (LAA) dense spontaneous echo contrast (SEC) and LAAT to accurately identify patients at high risk for stroke. A retrospective analysis was conducted on 433 patients with AF receiving transesophageal echocardiography (TEE) in the First Affiliated Hospital of Soochow University from October 2019 to July 2022. These patients were assigned into a non-dense SEC/LAAT group or a dense SEC/LAAT group. We constructed a nomogram model dependent on the odds ratios (ORs) of logistic regression and subsequently compared its performance with two models, CHADS2 and CHA2DS2-VASc. Female gender, high D-dimer level, low left ventricular ejection fraction, low left atrial ejection fraction, and low left atrial reservoir strain rate were found to be independent factors for predicting LAA SEC/LAAT, with OR values and 95% confidence intervals of 2.811 (1.445-5.469), 2.460 (1.230-4.921), 0.961 (0.927-0.996), 0.950 (0.932-0.967), and 0.173 (0.035-0.848), respectively. The consistency statistic of the nomogram based on these given predictive factors was 0.921, and the calibrated consistency statistic was 0.903. According to receiver operation curve analysis and decision curve analysis, the nomogram was demonstrated to be superior to the CHADS2 and CHA2DS2-VASc models in predicting LAA dense SEC/LAAT. The net reclassification improvement and integrated discrimination improvement of the nomogram were 0.449 (0.324-0.575) and 0.461 (0.408-0.515), when compared with the CHADS2 model, and were 0.521 (0.411-0.632), and 0.432 (0.400-0.504), respectively, when compared with the CHA2DS2-VASc models. The nomogram model constructed in this study demonstrated excellent performance in predicting LAA dense SEC/LAAT, displaying a superior ability to that of the CHADS2 and CHA2DS2-VASc models.

Efficacy of Low-Dose Isoproterenol Infusion for the Exclusion of a Left Atrial Appendage Thrombus in Patients With Dense Spontaneous Echo Contrast Caused by Atrial Fibrillation.

In patients with atrial fibrillation (AF) and severe blood stasis in the left atrial appendage (LAA), dense spontaneous echo contrast (SEC) disturbs the distinct visualization of the LAA interior, thus making thrombus diagnosis inconclusive. We aimed to prospectively assess the efficacy and safety of a protocol for a low-dose isoproterenol (ISP) infusion to reduce SEC to exclude an LAA thrombus.Methods and Results: We enrolled 17 patients with AF and dense SEC (Grade 4 or sludge). ISP was infused with gradually increasing doses of 0.01, 0.02, and 0.03 μg/kg/min at 3-min intervals. After increasing the dose to 0.03 μg/kg/min for 3 min, or when the LAA interior was visible, the infusion was terminated. We reassessed the SEC grade, presence of an LAA thrombus, LAA function, and left ventricular ejection fraction (LVEF) within 1 min of ISP termination. Compared with baseline, ISP significantly increased LAA flow velocity, the LAA emptying fraction, LAA wall velocities, and LVEF (all P<0.01). ISP administration significantly reduced the SEC grade (median) from 4 to 1 (P<0.001). The SEC grade decreased to ≤2 in 15 (88%) patients, and the LAA thrombus was excluded. There were no adverse events. Low-dose ISP infusion may be effective and safe to reduce SEC and exclude an LAA thrombus by improving LAA function and LVEF.

Left atrial enlargement and high uric acid level are risk factors for left atrial thrombus or dense spontaneous echo contrast in atrial fibrillation patients with low to moderate embolic risk assessed by CHA2DS2-VASC score.

To investigate the correlation and predictive value of left atrial diameter and blood uric acid levels with the occurrence of left atrial thrombus or dense spontaneous echo contrast in atrial fibrillation patients with low to moderate CHA2DS2-VASc scores. A total of 849 inpatients diagnosed with atrial fibrillation who had low to moderate CHA2DS2-VASc scores and complete transesophageal echocardiography were included in this study. Among them, 66 patients had left atrial thrombus or dense spontaneous echo contrast. When different models were used to correct other known risk factors, acid levels and abnormal left atrial diameter were identified as additional risk factors for left atrial thrombus or dense spontaneous echo contrast. The incidence of left atrial thrombus or dense spontaneous echo contrast was higher in patients with abnormal serum uric acid levels than in the control group (12.4% vs. 5.6%, p < 0.05), and this difference persisted after correcting the baseline data with propensity score matching (10.6% vs. 4.1%, p < 0.05). Abnormal left atrial diameter was another risk factor suggested by regression analysis, with an increased incidence of left atrial thrombus or dense spontaneous echo contrast in the abnormal left atrial diameter group compared to the control group, both before (18.0% vs. 3.5%, p < 0.05) and after (15.5% vs. 5.2%, p < 0.05) propensity score matching. The best predictive value was obtained by adding both abnormal serum uric acid levels and abnormal left atrial diameter. Left atrial enlargement and high uric acid levels increase the risk of left atrial thrombus or dense spontaneous echo contrast in atrial fibrillation patients with low to moderate CHA2DS2-VASc scores.

Identifying Patients at High Risk of Left Atrial Appendage Thrombus Before Cardioversion: The CLOTS-AF Score.

Background Transesophageal echocardiography-guided direct cardioversion is recommended in patients who are inadequately anticoagulated due to perceived risk of left atrial appendage thrombus (LAAT); however, LAAT risk factors remain poorly defined. Methods and Results We evaluated clinical and transthoracic echocardiographic parameters to predict LAAT risk in consecutive patients with atrial fibrillation (AF)/atrial flutter undergoing transesophageal echocardiography before cardioversion between 2002 and 2022. Regression analysis identified predictors of LAAT, combined to create the novel CLOTS-AF risk score (comprising clinical and echocardiographic LAAT predictors), which was developed in the derivation cohort (70%) and validated in the remaining 30%. A total of 1001 patients (mean age, 62±13 years; 25% women; left ventricular ejection fraction, 49.8±14%) underwent transesophageal echocardiography, with LAAT identified in 140 of 1001 patients (14%) and dense spontaneous echo contrast precluding cardioversion in a further 75 patients (7.5%). AF duration, AF rhythm, creatinine, stroke, diabetes, and echocardiographic parameters were univariate LAAT predictors; age, female sex, body mass index, anticoagulant type, and duration were not (all P>0.05). CHADS2VASc, though significant on univariate analysis (P<0.001), was not significant after adjustment (P=0.12). The novel CLOTS-AF risk model comprised significant multivariable predictors categorized and weighted according to clinically relevant thresholds (Creatinine >1.5 mg/dL, Left ventricular ejection fraction <50%, Overload (left atrial volume index >34 mL/m2), Tricuspid Annular Plane Systolic Excursion (TAPSE) <17 mm, Stroke, and AF rhythm). The unweighted risk model had excellent predictive performance with an area under the curve of 0.820 (95% CI, 0.752-0.887). The weighted CLOTS-AF risk score maintained good predictive performance (AUC, 0.780) with an accuracy of 72%. Conclusions The incidence of LAAT or dense spontaneous echo contrast precluding cardioversion in patients with AF who are inadequately anticoagulated is 21%. Clinical and noninvasive echocardiographic parameters may identify patients at increased risk of LAAT better managed with a suitable period of anticoagulation before undertaking cardioversion.

The novel left atrial appendage strain parameters are associated with thrombosis risk in patients with non-valvular atrial fibrillation.

We sought to explore a novel left atrial appendage (LAA) strain parameter which could represent the cumulative adverse impact of chronic Atrial fibrillation (AF) on the LAA function, and the relationship between the LAA strain parameter and thrombosis risk in patients with non-valvular AF. We enrolled 268 patients with non-valvular AF and 58 sinus rhythm subjects who underwent transesophageal echocardiography in the study. LAA longitudinal strain amplitude (LAA LSA) was defined as the sum of the value of the maximum positive peak strain (LAA PLS) and the absolute value of the minimum negative peak strain (LAA NLS). Dense spontaneous echo contrast (SEC) was defined as grade 3 or 4 SEC. Compared to sinus rhythm group, the global LAA strain parameters were significantly lower in paroxysmal AF (n = 148), and the lowest of them were found in persistent AF (n = 120), which suggested that the global LAA strain parameters could evaluate LAA function in sinus rhythm, paroxysmal AF and persistent AF. Compared with patients in AF without SEC/thrombus (n = 113), the regional and global LAA strain parameters were significantly depressed in AF with SEC/thrombus (n = 155). Multivariate logistic regression analyses showed that LAA global LSA (OR 0.768; 95% CI:0.569, 0.970; p = 0.027) was an independent predicter of the SEC/thrombus. Compared with patients in AF without dense SEC or thrombus (n = 210), the regional and global LAA strain parameters were significantly impaired in the patients with dense SEC/thrombus(n = 58). LAA global LSA (AUC 0.884) had the best predictable accuracy for dense SEC or thrombus, and outperformed LAA PLS, LAA NLS, CHA2DS2-VASc score and conventional LAA functional parameters that have been used in the evaluation blood flow stasis in LAA. LAA LSA showed excellent interobserver and intra-observer agreement beyond LAA PLS and LAA NLS. The novel LAA strain parameters, which were feasible and reproducible parameters for evaluation LAA mechanic function, had good predictive accuracy for blood flow stasis in LAA beyond conventional LAA functional parameters.

The value of left atrial longitudinal strain in evaluating left atrial appendage spontaneous echo contrast in non-valvular atrial fibrillation.

Spontaneous echo contrast (SEC) observed in transesophageal echocardiography (TEE) is a reliable predictor of the risk of future ischemic stroke in patients with non-valvular atrial fibrillation (NVAF). Left atrial strain globally reflects atrial function, remodeling and distensibility. The left atrial appendage (LAA) is a myogenic remnant of the left atrium, which can actively relax and contract. The left atrial appendage (LAA) is an important part of releasing the pressure of the left atrium. The key role of the left atrium is to regulate the left ventricular filling pressure, act as a reservoir for pulmonary venous return during ventricular contraction, and act as a conduit, transferring blood to the Left ventricle during early ventricular diastole. The purpose of this study was to explore the relationship between left atrial function and left atrial appendage spontaneous echo contrast (LAASEC). A retrospective study of 338 patients with non-valvular AF was conducted. Two-dimensional speckle-tracking echocardiography provided the following metrics of LA strain: LA strain during the reservoir phase (LASr), LA strain during the conduit phase (LAScd). LA or LAA has the dense SEC of more than grade 3, which is defined as mud like change or pre thrombosis. Patients with level 3 SEC (n = 81) has lower LASr than those with lower grades of SEC (n = 257) (7.20 ± 3.70 vs. 17.48 ± 8.67, P < 0.001). Multivariate logistic regression model showed that the type of atrial fibrillation (persistent∼), increased heart rate, decreased LASr were independently associated with the dense LAASEC (OR (CI 95%), 5.558 (1.618-19.09), 1.016 (1.006-1.026) 0.002, 1.224 (1.085-1.381), both P < 0.01). Venn Diagram showed that lower CHADVASC2 score groups had dense SEC cases. Receiver operating characteristic (ROC) curve was used for analyzing results and selecting cut off values. The cut off point for LASr < 8.85% and CHADVASC2 score was >2 scores with sensitivity and specificity were 79% and 85%. Lower LASr is independently associated with the dense LAASEC in NVAF and has incremental values superior to clinical scores. The decrease of LASr may be a potential non-invasive parameter for evaluating the higher risk of LAA thrombosis.

106 A CASE OF COMPLETE ATRIOVENTRICULAR BLOCK AND ALTERNATING BUNDLE BRANCH BLOCK DUE TO FULMINANT MYOCARDITIS

Abstract A 41-year-old man, without previous cardiological history, presented at the emergency department with hypotension and multi-organ failure. Laboratory testing showed elevated white cell blood count (16780/mcL; normal value 4000-11000/mcL; 90% neutrophils), high-sensibility troponin I (23247 ng/L; normal value &amp;lt;18 ng/L) and NT-pro-BNP (21914 pg/mL; normal value &amp;lt;300 pg/mL). At electrocardiogram (EKG) there was sinus rhythm with complete atrioventricular block and alternating right and left bundle branch block. Echocardiography revealed a moderate left ventricular (LV) dilatation, mild LV hypertrophy, severe biventricular dysfunction (LV Ejection Fraction - EF - 30%) with dense spontaneous echo contrast and moderate pulmonary hypertension (systolic pulmonary artery pressure 51 mmHg). After positioning a temporary pacemaker, the patient was transferred to our Cardiac Intensive Care Unit. After initial hemodynamic stabilization with endovenous inotropes, diuretics, and mechanical circulatory support (intra-aortic balloon pump), coronary angiography was performed showing normal coronary arteries. Since fulminant myocarditis was suspected and magnetic resonance was not feasible due to the patient's instability, an endomyocardial biopsy (EMB) was performed with the evidence of myocardial edema, initial myocardial fibrosis, and the concomitant presence of lymphocytic and eosinophilic endo-myocarditis (despite normal eosinophilic blood count) without evidence of active viral replication. After careful exclusion of latent or active infections, high doses of corticosteroids and azathioprine were initiated, with rapid laboratoristic and clinical response. EKG showed AV block regression and QRS width's normalization, so the pacemaker was removed. LVEF rapidly improved and was completely normalized at discharge after two weeks. In the early follow-up, a cardiac magnetic resonance (CMR) was performed with evidence of persistency of mildly dilated LV, normalization of LV wall thickness and biventricular function, a diffuse increase of T1 relaxation time, increased T2 signal of the anterior and septal walls, and intramural anteroseptal late gadolinium enhancement (LGE). Fulminant myocarditis is a rare presentation of acute myocarditis, with low incidence but high mortality. The inflammation of the myocardium itself leads to acute heart failure, cardiogenic shock, and cardiac arrhythmias, including sinus arrest, AV block, ventricular tachycardia, and ventricular fibrillation during the acute phase. In our case, AV block could be an expression of anteroseptal involvement, documented at CMR. This localization has already been associated with worse clinical presentation and could be a marker of poor prognosis. Diagnosis and treatment of fulminant myocarditis require EMB, to obtain information about the etiology and active viral replication in the heart tissue. In our case, the florid inflammatory state and the absence of viral replication allowed prompt treatment with immunosuppressors, with a quick and full recovery of biventricular function in only two weeks.

Left atrial appendage mechanical dispersion assessed by speckle-tracking echocardiography as a determinant of left atrial appendage stasis in patients with non-valvular atrial fibrillation

Abstract Background We sought to investigate the relationship of left atrial appendage (LAA) mechanical dispersion (MD) with LAA dense spontaneous echo contrast (SEC) or thrombus, and to compare its usefulness in the identification of thrombogenesis with left atrial (LA) MD or LA/LAA strain parameters in patients with nonvalvular atrial fibrillation (AF). Methods We conducted a cross-sectional study of 493 consecutive patients with AF (median age 65, male 66.9%) who underwent echocardiography prior to catheter ablation. We measured the LAA and LA global longitudinal strain (GLS) using speckle-tracking echocardiography (STE). LAA MD and LA MD was defined as the standard deviation (SD) of time to peak positive strain corrected by the R-R interval. Results Patients with LAA dense SEC/thrombus (n=70) had significantly higher LAA MD than controls (n=423) (median 14.20% vs 9.35%). Areas under the receiver-operating curve for CHA2DS2-VASc score plus LAA MD, LAA GLS or LA GLS were comparable (0.830, 0.843 and 0.809) and superior to that combined with LA MD (0.762, all p&amp;lt;0.01). Multivariable analysis showed that LAA MD was an independent determinant of LAA dense SEC/thrombus in four different models (Odds ratio, 1.23–1.24; P&amp;lt;0.001), and provided additional diagnostic value over clinical and standard echocardiographic parameters. Whereas LA MD was not independently associated with LAA dense SEC/thrombus and had no incremental predictive value. Conclusion LAA mechanical dispersion provided incremental information over conventional risk factors in the identification of LAA dense SEC or thrombus in AF patients and is superior to LA mechanical dispersion. Funding Acknowledgement Type of funding sources: None.

Clinical risk prediction for left atrial appendage thrombus among patients with atrial fibrillation

Abstract Background Exclusion of left atrial appendage thrombus (LAAT) by transoesophageal echocardiography (TOE) is recommended in patients with inadequate anticoagulation prior to direct cardioversion (DCR) or catheter ablation for atrial fibrillation/flutter (AF/AFL). LAAT risk factors in this population remain poorly defined. Purpose Determine LAAT predictors in AF/AFL patients undergoing pre-procedural TOE. Methods We evaluated available clinical and transthoracic echocardiographic (TTE) parameters in AF/AFL patients undergoing TOE between 1999–2022 in our institution in Melbourne, Australia. Regression analysis identified predictors of LAAT, which were applied to a weighted score developed in the derivation cohort (70%) and validated in the remaining 30%. Results Of 627 patients (age 62±12 years, 27% female, AF 84%,AFL 16%, left ventricular ejection fraction (LVEF) 44±20%), 24% had LAAT and 13.8% dense spontaneous echo contrast precluding DCR. Anticoagulation was NOAC 56.5%, warfarin 32.1% and none in 11.4%. In the LAAT cohort, thrombus resolution occurred in 39% on serial transoesophageal imaging with a median time to resolution of 131 days (IQR 54–398). Diabetes (p=0.004), prior stroke (p=0.009), coronary disease (p=0.015), renal impairment (p&amp;lt;0.001) and CHADS2VASc &amp;gt;2 (73% vs. 55%, p&amp;lt;0.001) were higher in the LAAT cohort. Age (p=0.093), gender (p=0.689), BMI (p=0.828), anticoagulant type (p=0.316) and diabetes (p=0.107) were not univariate predictors, whereas anticoagulation duration (&amp;lt;30 days), creatinine and TTE markers of remodeling (LVEF, LAVI, RVSP and TAPSE) were independent predictors on univariate and multivariate regression; CHADS2VASc was not significant after adjustment (p=0.090). The weighted risk model included continuous (age, creatinine, LVEF, LAVI, TAPSE and RVSP) and categorical (anticoagulation duration) variables with excellent predictive performance: AUC 0.872 (95% CI 0.798–0.946), PPV 91%, NPV 70% and accuracy 80%. Conclusion A novel LAAT risk model comprising clinical and echocardiographic parameters enhances risk prediction over CHADS2VASc in AF/AFL and may guide the need for pre-procedural TOE imaging. Funding Acknowledgement Type of funding sources: None.

Left Atrial Appendage Mechanical Dispersion Assessed by Speckle-Tracking Echocardiography as a Determinant of Left Atrial Appendage Blood Stasis in Patients With Atrial Fibrillation.

AimsWe sought to investigate the relationship of left atrial appendage (LAA) mechanical dispersion (MD) with LAA dense spontaneous echo contrast (SEC) or thrombus, and to compare its usefulness in the identification of thrombogenesis with left atrial (LA) MD or LA/LAA strain parameters in patients with atrial fibrillation (AF).MethodsWe conducted a cross-sectional study of 493 consecutive patients with AF [65(58.5–71.0) years, male 66.9%] who underwent echocardiography prior to catheter ablation. We measured the LAA and LA global longitudinal strain (GLS) using speckle-tracking echocardiography (STE). LAA MD and LA MD was defined as the standard deviation (SD) of time to peak positive strain corrected by the R-R interval.ResultsPatients with LAA dense SEC/thrombus (n = 70) had significantly higher LAA MD than controls (n = 423) [median 14.2(11.6–16.8)% vs 9.4(6.2–12.1)%, p < 0.01]. Multivariable analysis showed that LAA MD was independently associated with LAA dense SEC/thrombus in four different models (Odds ratio, 1.23–1.24; p < 0.01), and provided additional diagnostic value over clinical and standard echocardiographic parameters. Whereas, LA MD was not independently associated with LAA dense SEC/thrombus and had no incremental value over other LA/LAA mechanical parameters.ConclusionLAA mechanical dispersion was an independent determinant of LAA dense SEC/thrombus in AF patients, incremental to conventional risk factors and superior to LA mechanical dispersion.

Comparison of left atrial and atrial appendage mechanics to stratify the risk of left atrial/atrial appendage stasis in patients with non-valvular atrial fibrillation

Abstract Funding Acknowledgements Type of funding sources: None. Background Left atrial appendage (LAA) and left atrial (LA) dysfunction are associated with the presence of thrombus and spontaneous echo contrast (SEC) within LAA. However, the role of LAA mechanical dispersion (MD) in contributing to thrombogenesis has not been fully addressed and compared with LA MD or LA/LAA GLS. We sought to investigate the relationship of LAA MD with LAA dense SEC or thrombus, and to compare its additional value with other LA/LAA mechanical parameters in patients with nonvalvular atrial fibrillation (AF). Methods We conducted a cross-sectional study of 493 consecutive patients with AF (median age 65, male 66.9%) who underwent echocardiography prior to catheter ablation. Of these, 70(14.2%) patients had dense SEC or thrombus in LAA. We measured the LAA and LA longitudinal strain using speckle-tracking echocardiography (STE). LAA MD and LA MD was defined as the standard deviation (SD) of time to peak positive strain corrected by the R-R interval. Results Patients with LAA dense SEC/thrombus (n=70) had significantly higher LAA MD (median 14.20% (11.60%,16.80%) vs 9.35 % (6.23%,12.07%)) than controls (n = 423). Areas under the receiver-operating curve (AUC) for CHA2DS2-VASc score plus LAA MD, LAA GLS or LA GLS were comparable (0.843,0.830 and 0.809) and superior to that combined with LA MD (0.762, p&amp;lt;0.01). Multivariable analysis showed that LAA MD was an independent determinant of LAA dense SEC/thrombus in four different models (Odds ratio, 1.23-1.24; P &amp;lt; 0.001), and provided additional diagnostic value over clinical and standard echocardiographic parameters. Whereas LA MD was not significantly associated with LAA dense SEC/thrombus and had no incremental predictive value. Conclusion LAA mechanical dispersion provided incremental information over conventional risk factors in the identification of LAA dense SEC or thrombus in AF patients and is superior to LA mechanical dispersion.

The Prognostic Nutritional Index May Predict Left Atrial Appendage Thrombus or Dense Spontaneous Echo Contrast in Patients With Atrial Fibrillation.

ObjectivesThe prognostic nutritional index (PNI) is an independent predictor of adverse outcomes in patients with cardiovascular diseases. The presence of left atrial appendage thrombus (LAAT) or spontaneous echo contrast (SEC) is associated with ischemic stroke. The present study aimed to investigate the relationship between the PNI and LAAT/dense SEC in patients with non-valvular atrial fibrillation (AF).MethodsIn patients with non-valvular AF, we compared demographics, clinical characteristics, and prevalence of LAAT/dense SEC according to the levels of the PNI. The relationship between the PNI and LAAT/dense SEC was observed.ResultsA total of 406 patients with non-valvular AF were consecutively included from March 2015 to February 2019. Of the study population, 53 patients had LAAT/dense SEC. The percentages of LAAT/dense SEC were 20.4, 14.1, and 4.5% in subjects from the lowest to the highest tertile of the PNI, respectively. Multivariate logistic analysis demonstrated that the PNI was an independent predictor for LAAT/dense SEC (OR 0.89; 95% CI, 0.82–0.97; P = 0.007). Receiver operating characteristic curve analysis revealed that the optimal cutoff value of the PNI for predicting LAAT/dense SEC was 48.0 (area under the curve: 0.68; 95% CI, 0.61–0.75; P < 0.001). The sensitivity and specificity were 83.0 and 47.6%, respectively. The risk of LAAT/dense SEC in patients with a PNI ≤ 48.0 was 2.57-fold higher than that in those with a PNI > 48.0.ConclusionThe PNI, calculated based on serum albumin and lymphocyte count, was inversely correlated with LAAT/dense SEC in patients with non-valvular AF. Therefore, it may be considered a predictor for LAAT/dense SEC.

Relationship of warfarin versus DOACs with thrombogenic milieu in the left atrium among patients with nonvalvular atrial fibrillation

AbstractBackgroundThrombogenic milieu (TM) within the left atrium plays a pivotal role in the pathogenesis of thromboembolic events, for which anticoagulation treatment is indicated typically on the mandatory basis. Little is known, however, about which regimen of anticoagulation, warfarin or direct oral anticoagulants (DOACs), is more likely associated with TM. We evaluated relative relationship of the two treatment options with concurrently‐observed TM in patients with nonvalvular atrial fibrillation (AF) who underwent transesophageal echocardiography.MethodsTM was defined as the presence of either left atrial spontaneous echo contrast (SEC) or thrombus, or both. To determine which regimen was more likely related to TM, we firstly compared the prevalence of TM in 208 patients taking warfarin (Warfarin group) versus 486 patients taking DOACs (DOAC group); and secondly, did the same analysis after propensity score matching.ResultsWarfarin group was more likely associated with TM compared with DOAC group (46% vs 29%, p &lt; 0.001). Similar findings were observed for dense SEC (18% vs 7%, p &lt; 0.001) and thrombus (4% vs 1%, p = 0.057). The propensity score matching (198 patients for each group), where several baseline parameters were matched including age, gender, chronicity of AF, estimated glomerular filtration rate and B‐type natriuretic peptide as well as the left ventricular ejection fraction, resulted in similar findings to the original groups (TM, 47% vs 32%, p = 0.002; dense SEC, 18% vs 7%, p = 0.001; thrombus, 4% vs 1%, p = 0.047).ConclusionsThis study may strengthen the data on randomized trials that DOACs are superior to warfarin in preventing thromboembolic events in nonvalvular AF patients. Further studies are required to elucidate the details behind this difference.

Porphyromonas gingivalis and left atrial appendage spontaneous echo contrast in atrial fibrillation ablation candidates.

Atrial fibrillation (AF) is associated with a fivefold risk of stroke and thrombotic embolism, which are usually derived from the left atrial appendage (LAA). Spontaneous echo contrast (SEC) is known as a risk factor for thrombosis. Porphyromonas gingivalis (P. gingivalis) has some prothrombotic effects and plays a key role in periodontitis and oral-systemic disease connection. We aimed to clarify the relationship between P. gingivalis and LAA SEC among AF patients. A total of 569 AF ablation candidates were enrolled in the present study. LAA SEC was categorized into nondense SEC and dense SEC based on transesophageal echocardiography. Serum immunoglobulin G antibody titers of P. gingivalis fimA subtypes (types I-IV) were measured with an enzyme-linked immunosorbent assay. The levels of antibody titers were categorized into high (> mean + 3 standard deviation) and low values. A total of 513 (90%) patients were included in the nondense SEC group, and 56 (10%) were included in the dense SEC group. Multivariate regression analysis revealed that the high-value serum antibody titers of P. gingivalis types II and IV were independently associated with dense SEC [type II: adjusted odds ratio (OR) 2.220; 95% confidence interval (CI) 1.062-4.643; P = 0.02; and type IV: adjusted OR 3.169; 95% CI 1.058-6.657; P = 0.002]. The results revealed that P. gingivalis types II and IV are related to LAA SEC severity among AF patients who receive appropriate anticoagulation therapy.

Usefulness of transesophageal echocardiography before cardioversion in atrial arrhythmias.

Although many thromboembolism risk factors are well defined, formation of thrombus or dense spontaneous contrast (sludge) in the left atrium remains enigmatic and confounding. Exclusion of the thrombus is extremely important with respect to planned reversal of sinus rhythm. Data regarding the routine transesophagal echocardiography (TEE) before cardioversion are inconclusive. The authors focused on analyzing the usefulness of TEE before cardioversion by assessment of factors influencing the risk of thrombus and/or dense spontaneous echo contrast with the intention of extending indications for TEE in the group with a high risk of thrombus or to forgo TEE in the low risk group. Two hundred sixty-nine consecutive patients with persistent (> 48 h) atrial fibrillation or atrial flutter, in whom a direct current cardioversion was planned, were undergoing TEE for the detection of the left atrial thrombus or dense spontaneous echo contrast. Additional clinical and echocardiographic data were collected. The relationship between both thrombus and dense spontaneous echo contrast and covariates was analyzed with the use of binary logistic regression. Left atrium (LA) appendage (LAA) thrombus and/or sludge were detected in 79 (29%) patients. Signs of dementia in mini-mental state examination (hazard ratio [HR]: 1.16; p = 0.005), low velocities in LAA (HR: 3.38; p = 0.032); presence of spontaneous echo contrast in LA (HR: 3.38; p = 0,003) consecutive episode of AF (HR: 2.27; p = 0,046); longer duration of atrial fibrillation (HR: 1.009; p = 0.022); were significant predictors of thrombus and/or dense spontaneous echo contrast. None of the patients with a CHA2DS2VASc score ≤ 1 had thrombus or sludge in the LAA. Among patients with a CHA2DS2VASc score > 1, the prevalence of thrombus or sludge in LAA was independent of the CHA2DS2VASc score value. Amongst many factors, including an established as risk for thromboembolism only a few of them increased the risk for the presence of thrombus in LAA: low velocities in LAA, presence of spontaneous echo contrast, longer duration of arrhythmia, consecutive (not first) arrhythmia episode and signs of dementia from a mini-mental state examination questionnaire. It was believed that there could be a need for an extension of indications of TEE in vast majority of the patients with atrial arrhythmias, due most often to an unpredictable occurrence of thrombus and potentially disastrous thromboembolism. The only exception could have been the group of the patients with a CHA2DS2VASc score ≤ 1.

Presence of Spontaneous Echo Contrast on Point-of-Care Vascular Ultrasound and the Development of Major Clotting Events in Coronavirus Disease 2019 Patients.

This was a retrospective cohort study of 39 adult patients admitted to the ICU with a confirmed coronavirus disease 2019 diagnosis at a large tertiary-care academic medical center. Patients were included if they had undergone a vascular ultrasound examination during their ICU admission. Overall, 48 venous ultrasound studies among the 39 patients were reviewed in blinded fashion by two reviewers for the presence of venous spontaneous echo contrast, and charts were analyzed for laboratory data and outcomes. pontaneous echo contrast correlated with serum viscosity (mean values of 2.64, 2.54, and 2.04 cP for dense spontaneous echo contrast, spontaneous echo contrast , and no spontaneous echo contrast, respectively, with a p value of 0.0056 for spontaneous echo contrast compared with negative spontaneous echo contrast) and hyperfibrinogenemia (mean values of 726.6, 668.5, and 566.6 mg/dL for dense spontaneous echo contrast, positive spontaneous echo contrast, and negative spontaneous echo contrast, respectively, with a p value of 0.0045 for dense spontaneous echo contrast compared with negative spontaneous echo contrast). About 36% of patients with dense spontaneous echo contrast and 33% of individuals with positive spontaneous echo contrast experienced significant clotting events compared with 17% of those with negative spontaneous echo contrast. A total of 19% of patients with spontaneous echo contrast suffered a cardiac arrest following a major clotting event, and there were no cardiac arrests from clotting events in the negative spontaneous echo contrast group. There was no association with the presence of spontaneous echo contrast and right or left cardiac function or other laboratory values such as d-dimer, external thromboelastometry - maximum lysis, platelet counts, C-reactive protein, or interleukin-6. Point-of-care venous ultrasonography is easily performed and reliably interpreted for visualization of spontaneous echo contrast. The presence of spontaneous echo contrast in patients with coronavirus disease 2019 is associated with hyperviscosity and increased rates of thrombotic events and complications.

Incidence, predictors and outcomes of device-related thrombus after left atrial appendage closure with the WATCHMAN device-Insights from the EWOLUTION real world registry.

In this analysis of the EWOLUTION registry, we evaluated the incidence, relevance and predictors of device-related thrombus in a large multi-center real-world cohort undergoing LAAc with the WATCHMAN device. We analyzed the 835 patients who underwent percutaneous LAA closure with the WATCHMAN device in the EWOLUTION registry in whom at least one TEE follow up was performed. Patients were 74 ± 9 y/o and were at high risk for stroke and bleeding (CHA2DS2-VASC-Score 4.3± 1.7; HAS-BLED-Score 2.3± 1.2). Device-related thrombus was detected in 4.1% (34/835) after a median of 54 days (IQR 42-111 days) with 91.2% (31/34) being detected within 3months after the procedure or at the time of first TEE. Hereby DRT occurred irrespective of postprocedural anticoagulation. Patients with DRT more frequently had long-standing, non-paroxysmal atrial fibrillation (82.4 vs. 64.9%, p< .01), evidence of dense spontaneous echo contrast (26.5 vs. 11.9%, p= .03) and larger LAA diameters at the ostium (22.8± 3.5 vs. 21.1± 3.5 mm, p< .01) compared to patients without DRT. Left ventricular ejection fraction, device compression ratio and the incidence of renal dysfunction did not differ between the two groups. In a multivariate analysis, only non-paroxysmal atrial fibrillation identified as an independent predictor of developing DRT. Specific treatment of DRT was initiated in 62% (21/34) of patients whereas resolution was confirmed in 86% (18/21) of cases. Overall, no significant differences in annual rates of stroke/TIA or systemic embolism were observed in patients with or without DRT (DRT 1.7 vs. No-DRT 2.2%/year, p= .8). In real-world patients undergoing LAAc with the WATCHMAN device, DRT is rare. DRT was most frequently detected within the first 3months after LAAc regardless of post-procedural regimen and was not associated with an increased risk of stroke or SE. While long-standing atrial fibrillation was the only independent factor associated with DRT, medical treatment of DRT resulted in a resolution of thrombi in most cases.

Association betweenLeft Atrial Appendage function assessed by speckle-tracking echocardiography and the presence ofLeft Atrial Appendage stasis in patients with atrial fibrillation

Abstract Objectives The aim of this study was to determine the association of LAA left atrial appendage funtion as assessed by speckle-tracking imaging with LAA stasis and thrombus in patients with nonvalvular atrial fibrillation (AF). Methods A total of 154 consecutive patients with AF referred for transesophageal echocardiography (TEE) were prospectively enrolled. Of these, 29 (18.8%) patients had LAA dense spontaneous echo contrast (SEC) and/or thrombus. Besides standard echocardiography we assessed global, basal, middle and apical LAA longitudinal strain (LS) in mid-esophageal TEE views obtained at 0°, 45°, 90° and 135° by using speckle-tracking echocardiography (STE). Results Patients were comparable with regard to the clinical data. A subgroup with LAA stasis or thrombus had enlarged LAA size, impaired LAA emptying fraction (LAAEF) and reduced LAA emptying velocity than control group.LAA global and segmental LS were significantly decreased in patients with dense SEC or thrombus. Receiver operating characteristic curve analysis revealed that the LAAEF of 61.5%, the LAA GLS of 8.02%, LAA segmental LS of (basal) 8.07%, (middle) 9.08%, (apical) 8.43% (P&amp;lt;0.0001) were the optimal cutoff values for distinguishing both subgroups. All the LAA strain parameters as well as LAAEF were independently associated with the presence of LAA stasis or thrombus in multivariate analyses, with additional significance over the CHA2DS2-VASc score. Conclusion Speckle-tracking echocardiography may be used to describe LAA function during AF, allowing identification of patients with higher risk of LAA stasis or thrombus and providing incremental value over the CH2ADS2-VASc Score. Figure 1 Funding Acknowledgement Type of funding source: None