Can transesophageal echocardiography be safely omitted in patients scheduled for elective ablation of atrial arrhythmias? Data based on the LATTEE registry.

BACKGROUND: According to the present guidelines, transesophageal echocardiography (TEE) before scheduled catheter ablation (CA) for atrial arrhythmias (atrial fibrillation [AF] or atrial flutter [AFL]) is not deemed obligatory for optimally anticoagulated patients. However, daily clinical practice significantly differs from the recommendations. AIMS: That study aimed to identify transthoracic echocardiographic parameters that could be useful in revealing patients without left atrial thrombus (LAT), thereby contributing to avoiding unnecessary TEE before scheduled CA. METHODS: This is a sub-analysis of a multicenter, prospective, observational study - LATTEE registry. A total of 1346 patients referred for TEE before scheduled CA of AF/AFL were included. RESULTS: LAT was present in 44 patients (3.3%) and absent in the remaining 1302, who were younger, more likely to have paroxysmal AF, and displayed sinus rhythm during TEE. Additionally, they exhibited a lower incidence heart failure, diabetes, systemic connective tissue disease, and chronic obstructive pulmonary disease. Furthermore, they had a lower CHA2DS2-VASc score and a higher prevalence of direct oral anticoagulants. Echocardiographic parameters, including left ventricular ejection fraction (LVEF) > 65%, left atrial diameter (LAD) < 40 mm, left atrial area (LAA) < 20 cm2, left atrial volume (LAV) < 113 ml, and left atrial volume index (LAVI) < 51 ml/m2, demonstrated 100% sensitivity and 100% negative predictive value for the LAT absence, and weremet by 417 patients. Additional echocardiographic indices: LVEF/LAD > 1.4, LVEF/LAVI > 1.6 and LVEF/LAA > 2.7 identified an additional 57 patients, bringing the total predicted LAT-free patients to 474 (35%). CONCLUSIONS: Simple echocardiographic parameters could help identify individuals for whom TEE could be safely omitted before scheduled for elective CA due to atrial arrhythmias.

Artificial intelligence in detecting left atrial appendage thrombus by transthoracic echocardiography and clinical features: the Left Atrial Thrombus on Transoesophageal Echocardiography (LATTEE) registry.

AIMS: Transoesophageal echocardiography (TOE) is often performed before catheter ablation or cardioversion to rule out the presence of left atrial appendage thrombus (LAT) in patients on chronic oral anticoagulation (OAC), despite associated discomfort. A machine learning model [LAT-artificial intelligence (AI)] was developed to predict the presence of LAT based on clinical and transthoracic echocardiography (TTE) features. METHODS AND RESULTS: Data from a 13-site prospective registry of patients who underwent TOE before cardioversion or catheter ablation were used. LAT-AI was trained to predict LAT using data from 12 sites (n = 2827) and tested externally in patients on chronic OAC from two sites (n = 1284). Areas under the receiver operating characteristic curve (AUC) of LAT-AI were compared with that of left ventricular ejection fraction (LVEF) and CHA2DS2-VASc score. A decision threshold allowing for a 99% negative predictive value was defined in the development cohort. A protocol where TOE in patients on chronic OAC is performed depending on the LAT-AI score was validated in the external cohort. In the external testing cohort, LAT was found in 5.5% of patients. LAT-AI achieved an AUC of 0.85 [95% confidence interval (CI): 0.82-0.89], outperforming LVEF (0.81, 95% CI 0.76-0.86, P < .0001) and CHA2DS2-VASc score (0.69, 95% CI: 0.63-0.7, P < .0001) in the entire external cohort. Based on the proposed protocol, 40% of patients on chronic OAC from the external cohort would safely avoid TOE. CONCLUSION: LAT-AI allows accurate prediction of LAT. A LAT-AI-based protocol could be used to guide the decision to perform TOE despite chronic OAC.

Echocardiographic predictors of thrombus in left atrial appendage-The role of novel transthoracic parameters.

Introduction: The left atrium appendage thrombus (LAAT) formation is a complex process. A CHA2DS2-VASc scale is an established tool for determining the thromboembolic risk and initiation of anticoagulation treatment in patients with atrial fibrillation or flutter (AF/AFL). We aimed to identify whether any transthoracic echocardiography (TTE) parameters could have an additional impact on LAAT detection. Methods: That is a sub-study of multicenter, prospective, observational study LATTEE (NCT03591627), which enrolled 3,109 consecutive patients with AF/AFL referred for transesophageal echocardiography (TEE) before cardioversion or ablation. Results: LAAT was diagnosed in 8.0% of patients. The univariate logistic regression analysis [based on pre-specified in the receiver operating characteristic (ROC) analysis cut-off values with AUC ≥ 0.7] identified left ventricular ejection fraction (LVEF) ≤ 48% and novel TTE parameters i.e., the ratios of LVEF and left atrial diameter (LAD) ≤ 1.1 (AUC 0.75; OR 5.64; 95% CI 4.03-7.9; p < 0.001), LVEF to left atrial area (LAA) ≤ 1.7 (AUC 0.75; OR 5.64; 95% CI 4.02-7.9; p < 0.001), and LVEF to indexed left atrial volume (LAVI) ≤ 1.1 (AUC 0.75, OR 6.77; 95% CI 4.25-10.8; p < 0.001) as significant predictors of LAAT. In a multivariate logistic regression analysis, LVEF/LAVI and LVEF/LAA maintained statistical significance. Calculating the accuracy of the abovementioned ratios according to the CHA2DS2-VASc scale values revealed their highest predictive power for LAAT in a setting with low thromboembolic risk. Conclusion: Novel TTE indices could help identify patients with increased probability of the LAAT, with particular applicability for patients at low thromboembolic risk.

Risk factors for left atrial thrombus in younger patients (aged < 65 years) with atrial fibrillation or atrial flutter: Data from the multicenter left atrial thrombus on transesophageal echocardiography (LATTEE) registry.

Background: Our aim was to assess the characteristics and to identify predictors of left atrial thrombus (LAT) in patients under age 65 with atrial fibrillation (AF) or atrial flutter (AFl). Methods: We conducted a subanalysis of a multicenter, prospective, observational study [the LATTEE registry]. Consecutive AF/AFl patients referred for cardioversion or ablation were enrolled. Results: Of the 3,109 patients included in the study, 1,276 were under age 65 (41%). Compared to non-LAT patients, those with LAT (n = 76) had higher CHA2DS2-VASc score (p < 0.001), more frequently had non-paroxysmal AF/AFl (p < 0.001), heart failure (p < 0.001), history of diabetes mellitus (p = 0.001), transient ischemic attack (p = 0.04), coronary artery disease (p = 0.02), and chronic kidney disease (p < 0.001). The LAT patients were also more often smokers (p = 0.004) and were more frequently treated with vitamin K antagonists (VKAs) (p < 0.001). Transthoracic echocardiography revealed a higher left atrial area (p < 0.001), lower left ventricular ejection fraction (LVEF) (p < 0.001), and lower value of LA appendage emptying volume in LAT than in non-LAT patients (p < 0.001). LVEF (OR 2.95; 95% CI: 1.32-6.59, p = 0.008), non-paroxysmal AF/AFl (OR 7.1; 95% CI: 2.05-24.63, p = 0.002) and treatment with VKAs (OR 4.92; 95% CI: 2.48-9.75, p < 0.001) were identified as independent predictors of LAT in younger patients. Conclusions: Our study, which focused on younger patients with AF/AFl, indicated substantial clinical and echocardiographic differences between participants with and without LAT. In the AF/AFl patients younger than age 65, the independent predictors of LAT included non-paroxysmal AF/AFl, lower LVEF, and treatment with VKAs.

Increased Body Mass Index and Risk of Left Atrial Thrombus in Nonvalvular Atrial Fibrillation Patients-Data from the Left Atrial Thrombus on Transesophageal Echocardiography (LATTEE) Registry.

An increased body mass index (BMI) is associated with a higher incidence of atrial fibrillation (AF) and a higher risk of thromboembolic complications in AF patients. The aim of this study was to investigate the effect of BMI on the risk of left atrial thrombi (LATs) in patients with nonvalvular AF/atrial flutter (AFl) (NV AF/AFl). Patients diagnosed with NVAF/AFl (between November 2018 and May 2020) were selected from the multicenter, prospective, observational Left Atrial Thrombus on Transesophageal Echocardiography (LATTEE) registry that included AF/AFl patients referred for cardioversion or ablation followed by transesophageal echocardiography. A total of 2816 AF/AFl patients (63.6% males; mean age 65.8 years; mean BMI 29.8 kg/m2) were included in the study. Two hundred and twenty-two of them (7.9%) had LATs. Compared with normal-weight patients, those with BMIs ≥ 25 kg/m2 more frequently presented clinical factors potentially provoking LATs, such as non-paroxysmal AF/AFl (p = 0.04), hypertension (p < 0.001), and diabetes (p < 0.001); had higher CHA2DS2 scores (p < 0.001); and had larger LA dimensions (LA diameter and LA area) (p < 0.001 for both parameters). On the other hand, they showed some features negatively related to thromboembolic risk; for example, they were younger (p < 0.001) and were more often male (p = 0.002). In addition, patients with abnormal BMIs were more likely to be smokers (p = 0.006) and to be treated with oral anticoagulants (p = 0.005). Despite these differences in the prevalence of thromboembolic risk factors, the incidence of LATs was not increased in patients with abnormal body weight (overweight and obese compared to normal-weight patients) in this large real-life cohort of AF/AFl patients. This is probably due to the balanced composition regarding the prevalence of positive and negative thromboembolic risk factors.

Heart failure and the risk of left atrial thrombus formation in patients with atrial fibrillation or atrial flutter.

AIMS: The aim of the study was to evaluate the prevalence of left atrial thrombus (LAT) on transoesophageal echocardiography (TOE) in patients with atrial fibrillation or atrial flutter (AF/AFl) with reference to the presence of heart failure (HF) and its subtypes. METHODS AND RESULTS: The research is a sub-study of the multicentre, prospective, observational Left Atrial Thrombus on Transoesophageal Echocardiography (LATTEE) registry, which comprised 3109 consecutive patients with AF/AFl undergoing TOE prior to direct current cardioversion or catheter ablation. TOE parameters, including presence of LAT, were compared between patients with and without HF and across different subtypes of HF, including HF with preserved (HFpEF), mid-range (HFmrEF), and reduced ejection fraction (HFrEF). HF was diagnosed in 1336 patients (43%). HF patients had higher prevalence of LAT than non-HF patients (12.8% vs. 4.4%; P < 0.001). LAT presence increased with more advanced type of systolic dysfunction (HFpEF vs. HFmrEF vs. HFrEF: 7.4% vs. 10.5% vs. 20.3%; P < 0.001). Univariate analysis revealed that HFrEF (odds ratio [OR] 4.13; 95% confidence interval [95% CI]: 3.13-5.46), but not HFmrEF or HFpEF, was associated with the presence of LAT. Multivariable logistic regression indicated that lower left ventricular ejection fraction (OR per 1%: 0.94; 95% CI 0.93-0.95) was an independent predictor of LAT formation. Receiver operator characteristic analysis showed LVEF ≤48% adequately predicted increased risk of LAT presence (area under the curve [AUC] 0.74; P < 0.0001). CONCLUSION: The diagnosis of HFrEF, but neither HFmrEF nor HFpEF, confers a considerable risk of LAT presence despite widespread utilization of adequate anticoagulation.

Left Atrial Thrombus in Atrial Fibrillation/Flutter Patients in Relation to Anticoagulation Strategy: LATTEE Registry.

Background: Atrial fibrillation (AF) and flutter (AFl) increase the risk of thromboembolism. The aim of the study was to assess the prevalence of left atrial thrombus (LAT) in AF/AFl in relation to oral anticoagulation (OAC). Methods: LATTEE (NCT03591627) was a multicenter, prospective, observational study enrolling consecutive patients with AF/AFl referred for transesophageal echocardiography before cardioversion or ablation. Results: Of 3109 patients enrolled, 88% were on chronic, 1.5% on transient OAC and 10% without OAC. Of patients on chronic OAC, 39% received rivaroxaban, 30% dabigatran, 14% apixaban and 18% vitamin K antagonists (VKA). Patients on apixaban were oldest, had the worst renal function and were highest in both bleeding and thromboembolic risk, and more often received reduced doses. Prevalence of LAT was 8.0% (7.3% on chronic OAC vs. 15% without OAC; p < 0.01). In patients on VKA, prevalence of LAT was doubled compared to patients on non-VKA-OACs (NOACs) (13% vs. 6.0%; p < 0.01), even after propensity score weighting (13% vs. 7.5%; p < 0.01). Prevalence of LAT in patients on apixaban was higher (9.8%) than in those on rivaroxaban (5.7%) and dabigatran (4.7%; p < 0.01 for both comparisons), however, not after propensity score weighting. Conclusions: The prevalence of LAT in AF is non-negligible even on chronic OAC. The risk of LAT seems higher on VKA compared to NOAC, and similar between different NOACs.

Risk of Death and Ischemic Stroke in Patients with Atrial Arrhythmia and Thrombus or Sludge in Left Atrial Appendage at One-Year Follow-Up.

Thrombus in the left atrial appendage is a contraindication for cardioversion. Sludge is considered similarly as threatening as thrombus; however, the risk of death and ischemic stroke in patients with atrial arrhythmia and thrombus or sludge is not well-known. This study focused on assessing the risk of death and ischemic stroke at one-year follow-up in patients with atrial arrhythmia and thrombus or sludge, as well as the effectiveness of anticoagulation in thrombus resolution. 77 out of 267 (29%) of patients who were scheduled for cardioversion were diagnosed with thrombus or sludge. The annual mortality in patients with thrombus or sludge was 23%. In the group without thrombus, the annual mortality was 1.6%. Overall, 17% of patients with thrombus or sludge experienced ischemic stroke. In patients without thrombus, the risk of stroke was 1%. Sludge increased risk of stroke compared to those without thrombus or sludge by 11% vs. 1%, respectively. No differences in mortality or stroke prevalence were observed between sludge and thrombus. Thrombus or sludge in the LAA have a poor prognosis. A diagnosis of sludge has a similar impact on risk of ischemic strokes as does a diagnosis of thrombus.

Hemodynamic Effects of Permanent His Bundle Pacing Compared to Right Ventricular Pacing Assessed by Two-Dimensional Speckle-Tracking Echocardiography.

We compared the effects of right ventricular (RVP; n = 26) and His bundle (HBP; n = 24) pacing in patients with atrioventricular conduction disorders and preserved LVEF. Postoperatively (1D), and after six months (6M), the patients underwent global longitudinal strain (GLS) and peak systolic dispersion (PSD) evaluation with 2D speckle-tracking echocardiography, assessment of left atrial volume index (LAVI) and QRS duration (QRSd), and sensing/pacing parameter testing. The RVP threshold was lower than the HBP threshold at 1D (0.65 ± 0.13 vs. 1.05 ± 0.20 V, p < 0.001), and then it remained stable, while the HBP threshold increased at 6M (1.05 ± 0.20 vs. 1.31 ± 0.30 V, p < 0.001). The RVP R-wave was higher than the HBP R-wave at 1D (11.52 ± 2.99 vs. 4.82 ± 1.41 mV, p < 0.001). The RVP R-wave also remained stable, while the HBP R-wave decreased at 6M (4.82 ± 1.41 vs. 4.50 ± 1.09 mV, p < 0.02). RVP QRSd was longer than HBP QRSd at 6M (145.0 ± 11.1 vs. 112.3 ± 9.3 ms, p < 0.001). The absolute value of RVP GLS decreased at 6M (16.32 ± 2.57 vs. 14.03 ± 3.78%, p < 0.001), and HBP GLS remained stable. Simultaneously, RVP PSD increased (72.53 ± 24.15 vs. 88.33 ± 30.51 ms, p < 0.001) and HBP PSD decreased (96.28 ± 33.99 vs. 84.95 ± 28.98 ms, p < 0.001) after 6 months. RVP LAVI increased (26.73 ± 5.7 vs. 28.40 ± 6.4 mL/m2, p < 0.05), while HBP LAVI decreased at 6M (30.03 ± 7.8 vs. 28.73 ± 8.7 mL/m2, p < 0.01). These results confirm that HBP does not disrupt ventricular synchrony and provides advantages over RVP.

Usefulness of transesophageal echocardiography before cardioversion in atrial arrhythmias.

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Delayed presentation of left main coronary artery dissection due to catheter ablation in a patient with bicuspid aortic valve. Coincidence or manifestation of inherent vulnerability?

Left main coronary artery (LMCA) injury is an uncommon complication of catheter ablation. Due to the large myocardial area at risk, its presentation is usually acute with a dramatic course and life-threatening sequelae. Increased susceptibility to spontaneous coronary artery dissection has recently been implied in patients with bicuspid aortic valve (BAV). We present the first case of iatrogenic coronary dissection in a BAV patient, with an atypically delayed manifestation. The patient sustained ablation catheter-induced mechanical damage of LMCA due to its inadvertent penetration during the attempts to cross the aortic valve. After three days of recurring chest pain, he was readmitted with anterior myocardial infarction and imminent cardiogenic shock, and underwent emergent coronary stenting. Literature review suggests that in BAV inherent susceptibility to both spontaneous and iatrogenic coronary dissection may exist. Therefore, we advocate that in BAV extreme caution should be exercised during electrophysiological procedures involving the coronary artery cannulation for tagging or pace mapping, or when the left ventricle is to be entered retrogradely, and likewise in percutaneous coronary interventions. Such patients may be doubly predisposed to iatrogenic injury; firstly, by more difficult catheter manipulation in the malformed aortic cusps, and secondly, by the underlying vulnerability of coronary ostia. .