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.

Temporary transvenous cardiac pacing in cathlab - myocardial infarction versus other causes - differences, complications, and prognosis. Data from a single-center retrospective analysis.

BACKGROUND: Transvenous temporary cardiac pacing (TTCP) is a lifesaving procedure, but the incidence of complications and prognosis depends on the underlying cause. The aim of this study was to compare the characteristics, complications, and prognosis in patients with myocardial infarction (MI) requiring TTCP vs. patients with TTCP due to other causes. METHODS: The present analysis involved 244 cases in whom TTCP was performed between 2017 and 2021 in a high-volume cathlab. All the procedures were performed by an interventional cardiologist. MI constituted 46.3% of the patients (n = 113), including 63 ST-segment elevation MI patients (55.75%). Non-MI patients (control group) consisted of patients with any cause of bradycardia requiring TTCP. RESULTS: Myocardial infarction patients requiring TTCP are younger and have a higher prevalence of hypertension and heart failure. The pacing lead is more frequently inserted during asystole/resuscitation, and pacing was needed for a longer time. MI patients required cardiac implantable electronic device implantation less frequently than in other causes (22% vs. 82%, p < 0.01). The incidence of TTCP complications did not differ. The incidence of in-hospital death was 6.5-fold higher in TTCP patients with MI. Logistic regression showed MI to be a strong predictor of in-hospital death (odds ratio: 8.1; 95% confidence interval: 1.3-57.9). CONCLUSIONS: In-hospital mortality in MI patients requiring TTCP is 6.5-fold higher than in other patients with bradycardia. The complication rate of TTCP is similar in MI and non-MI patients. It is not TTCP but the severity of MI itself and the fact that a pacing lead is frequently implanted in asystole or during resuscitation that is responsible for the higher mortality rate.

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: We aimed to identify transthoracic echocardiographic parameters that could be useful in identifying patients without left atrial thrombus (LAT), which makes it possible to avoid unnecessary TEE before scheduled CA. METHODS: This is a sub-analysis of a multicenter, prospective, observational study - the 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 of 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 absence of LAT and were met by 417 patients. Additional echocardiographic indices: LVEF/LAD ≥1.4, LVEF/LAVI ≥1.6, and LVEF/LAA ≥2.7 identified 57 additional patients, bringing the total of predicted LAT-free patients to 474 (35%). CONCLUSIONS: Simple echocardiographic parameters could help identify individuals for whom TEE could be safely omitted before elective CA due to atrial arrhythmias.

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.

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.

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.

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.