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Thrombosis Research Mar 2023As a major complication of non-valvular atrial fibrillation (NVAF), left atrial appendage (LAA) thrombosis is associated with cerebral ischemic strokes, as well as high...
BACKGROUND
As a major complication of non-valvular atrial fibrillation (NVAF), left atrial appendage (LAA) thrombosis is associated with cerebral ischemic strokes, as well as high morbidity. Due to insufficient incorporation of risk factors, most current scoring methods are limited to the analysis of relationships between clinical characteristics and LAA thrombosis rather than detecting potential risk. Therefore, this study proposes a clinical data-driven machine learning method to predict LAA thrombosis of NVAF.
METHODS
Patients with NVAF from January 2014 to June 2022 were enrolled from Southwest Hospital. We selected 40 variables for analysis, including demographic data, medical history records, laboratory results, and the structure of LAA. Three machine learning algorithms were adopted to construct classifiers for the prediction of LAA thrombosis risk. The most important variables related to LAA thrombosis and their influences were recognized by SHapley Addictive exPlanations method. In addition, we compared our model with CHADS2 and CHADS2-VASc scoring methods.
RESULTS
A total of 713 participants were recruited, including 127 patients with LAA thrombosis and 586 patients with no obvious thrombosis. The consensus models based on Random Forest and eXtreme Gradient Boosting LAA thrombosis prediction (RXTP) achieved the best accuracy of 0.865, significantly outperforming CHADS2 score and CHA2DS2-VASc score (0.757 and 0.754, respectively). The SHAP results showed that B-type natriuretic peptide, left atrial appendage width, C-reactive protein, Fibrinogen and estimated glomerular filtration rate are closely related to the risk of LAA thrombosis in nonvalvular atrial fibrillation.
CONCLUSIONS
The RXTP-NVAF model is the most effective model with the greatest ROC value and recall rate. The summarized risk factors obtained from SHAP enable the optimization of the treatment strategy, thereby preventing thromboembolism events and the occurrence of cardiogenic ischemic stroke.
Topics: Humans; Atrial Fibrillation; Atrial Appendage; Thrombosis; Thromboembolism; Risk Factors; Stroke
PubMed: 36764084
DOI: 10.1016/j.thromres.2023.01.001 -
Heart (British Cardiac Society) Sep 2019We aimed to identify predictors of left atrial appendage (LAA) thrombus in patients with atrial fibrillation (AF) and to enhance the prognostic value of the CHADS-VASc...
OBJECTIVE
We aimed to identify predictors of left atrial appendage (LAA) thrombus in patients with atrial fibrillation (AF) and to enhance the prognostic value of the CHADS-VASc score.
METHODS
Derivation cohort included 1033 consecutive AF patients referred for catheter ablation or direct current cardioversion, in whom transoesophageal echocardiography (TOE) was performed prior to the procedure. Logistic regression analysis was used to identify predictors of LAA thrombus on TOE. Receiver operating characteristic (ROC) curves were constructed to compare the newly developed score with the CHADS and CHADS-VASc scores in the derivation and the validation (n=320) cohort.
RESULTS
On TOE, LAA thrombus was present in 59 (5.7%) patients in the derivation cohort. Aside from variables encompassed by the CHADS-VASc score, LAA thrombus predictors included AF type (persistent/'permanent' vs paroxysmal) and renal dysfunction. These predictors were incorporated into the CHADS-VASc score. In ROC analysis, area under the curve (AUC) for the new score (CHADS-VASc-RAF score) was significantly higher (0.81) than those for the CHADS and CHADS-VASc scores (0.71 and 0.70, respectively). In the validation cohort, the CHADS-VASc-RAF score also performed significantly better (AUC of 0.88) than the CHADS and CHADS-VASc scores (AUC of 0.63 and 0.60, respectively).
CONCLUSION
In real-world AF patients with majority on oral anticoagulation, LAA thrombus was found in approximately 6%. Two variables not included in the CHADS-VASc score (AF type and renal dysfunction) proved strong, independent predictors of LAA thrombus and might improve thromboembolic risk stratification.
Topics: Aged; Anticoagulants; Atrial Appendage; Atrial Fibrillation; Atrial Function, Left; Catheter Ablation; Decision Support Techniques; Echocardiography, Transesophageal; Electric Countershock; Female; Humans; Kidney; Kidney Diseases; Male; Middle Aged; Poland; Predictive Value of Tests; Prevalence; Reproducibility of Results; Retrospective Studies; Risk Assessment; Risk Factors; Thrombosis
PubMed: 31040170
DOI: 10.1136/heartjnl-2018-314492 -
JACC. Cardiovascular Interventions Nov 2021
Topics: Anticoagulants; Atrial Appendage; Atrial Fibrillation; Humans; Thrombosis; Treatment Outcome
PubMed: 34656491
DOI: 10.1016/j.jcin.2021.08.004 -
JACC. Clinical Electrophysiology Jan 2023
Topics: Humans; Atrial Appendage; Thrombosis; Atrial Fibrillation
PubMed: 36697188
DOI: 10.1016/j.jacep.2022.11.029 -
Global Heart 2022There are some evidence suggesting that total bilirubin (TBIL) appears to be associated with stroke in patients with nonvalvular atrial fibrillation (NVAF). The left...
OBJECTIVES
There are some evidence suggesting that total bilirubin (TBIL) appears to be associated with stroke in patients with nonvalvular atrial fibrillation (NVAF). The left atrial appendage (LAA) is the most common orgin of thrombus in patients with NVAF. The purpose of this study was to assess a possible relationship between plasma TBIL levels and LAA thrombus in NVAF patients.
METHODS
We retrospectively screened 459 consecutive hospitalized patients with NVAF at three AF centers, who underwent transesophageal echocardiography or cardiac CT. According to the examination results, the patients were divided into either the LAA thrombosis group (41 cases) or the no LAA thrombosis group (418 cases). Independent sample t test, Mann-Whitney U-test and chi-square test were used to compare and analyze the general clinical data of the two groups. Multivariate Logistic regression was used to analyze whether TBIL was a risk factor for LAA thrombosis in patients with NVAF. Pearson correlation analysis was used to explore the correlation between TBIL and other influencing factors. The predictive value of TBIL for LAA thrombosis in patients with NVAF was evaluated by ROC curve.
RESULTS
A total of 459 patients were enrolled in this study. Compared with the group without LAA thrombosis, the level of TBIL in LAA thrombosis group was significantly increased (21.34 ± 9.34 umol/L vs. 13.98 ± 4.25 umol/L, < 0.001). Multivariate logistic regression showed that TBIL level was a risk factor for LAA thrombosis (, 1.229; 95% , 1.122~1.345; < 0.001). The AUC of the ROC curve is 0.801 (95% , 0.725~0.877; < 0.001). At 17.4 umol/L of TBIL, the patient may have LAA thrombosis (sensitivity 73.2%; specificity 82.1%).
CONCLUSIONS
In patients with NVAF, TBIL level is positively associated with LAA thrombosis, and TBIL level may be an index reflecting LAA thrombosis.
Topics: Humans; Atrial Fibrillation; Atrial Appendage; Retrospective Studies; Thrombosis; Bilirubin
PubMed: 36578911
DOI: 10.5334/gh.1177 -
Cardiac Electrophysiology Clinics Jun 2023Left atrial appendage (LAA) epicardial exclusion has been associated with addressing 2 potential deleterious consequences attributed to the LAA, namely, thrombus... (Review)
Review
Left atrial appendage (LAA) epicardial exclusion has been associated with addressing 2 potential deleterious consequences attributed to the LAA, namely, thrombus formation and an arrhythmogenic contributor in advanced forms of atrial fibrillation. With more than 60 years of history, the surgical exclusion of the LAA has been firmly established. Numerous approaches have been used for surgical LAA exclusion including surgical resections, suture ligation, cutting and non-cutting staples, and surgical clips. Additionally, a percutaneous epicardial LAA ligation approach has been developed. A discussion of the various epicardial LAA exclusion approaches and their efficacy will be discussed, along with the salient beneficial affects on LAA thrombus formation, LAA electrical isolation and neuroendocrine homeostasis.
Topics: Humans; Atrial Appendage; Treatment Outcome; Cardiac Surgical Procedures; Echocardiography, Transesophageal; Atrial Fibrillation; Thrombosis; Sutures
PubMed: 37076232
DOI: 10.1016/j.ccep.2023.01.012 -
Arquivos Brasileiros de Cardiologia Oct 2022In the treatment of atrial fibrillation (AF), the most frequently sustained arrhythmia, with catheter ablation (CA) or electrical cardioversion (ECV), the periprocedural...
BACKGROUND
In the treatment of atrial fibrillation (AF), the most frequently sustained arrhythmia, with catheter ablation (CA) or electrical cardioversion (ECV), the periprocedural period is one of the most critical phases. Currently, the use of new direct action oral anticoagulants (DOAC) is increasingly frequent; however, in the real world, there are still few data on studies on the thrombus incidence in the left atrium (TrLA) or dense spontaneous contrast (DSC) on transesophageal echocardiogram (TEE).
OBJECTIVE
To evaluate the prevalence of events and association with risk factors in patients using DOACs. Primary objective: to analyze the prevalence of thrombus in the LA by TEE in patients using DOAC undergoing ECV/CA. Second, evaluate the association of comorbidities with the presence of thrombi and DSC.
METHODS
Retrospective cohort, single-center study with patients followed at the Arrhythmia Outpatient Unit (InCor-HCFMUSP). Patients indicated for procedures and using DOACs were selected, and their clinical/echocardiographic data were analyzed. A significance level of 5% was considered.
RESULTS
354 patients were included, a total of 400 procedures, from March 2012-March 2018. Thrombus in the LA was found in 11 patients (2.8%), associated with advanced age (p=0.007) and higher CHA2DS2-VASc (p<0.001) score. DSC in the LA before TEE was found in 29 patients (7.3%), with lower LVEF (p<0.038) and greater LA dimension (p<0.0001).
CONCLUSION
The incidence of LA thrombus and DSC in patients using DOC in the context of AF ECV/CA, although small, is not negligible. Patients with higher CHA2DS2-VASc scores, especially older and with larger LA diameter, are more prone to these echocardiographic findings.
Topics: Humans; Atrial Fibrillation; Retrospective Studies; Administration, Oral; Anticoagulants; Thrombosis; Heart Diseases; Echocardiography, Transesophageal; Atrial Appendage
PubMed: 36169450
DOI: 10.36660/abc.20210658 -
BMC Cardiovascular Disorders Sep 2021Thromboembolic events are the most serious complication of atrial fibrillation (AF), and the left atrial appendage (LAA) is the most important site of thrombosis in...
BACKGROUND
Thromboembolic events are the most serious complication of atrial fibrillation (AF), and the left atrial appendage (LAA) is the most important site of thrombosis in patients with AF. During the period of COVID-19, a non-invasive left atrial appendage detection method is particularly important in order to reduce the exposure of the virus. This study used CT three-dimensional reconstruction methods to explore the relationship between LAA morphology, LAA orifice area and its mechanical function in patients with non-valvular atrial fibrillation (NVAF).
METHODS
A total of 81 consecutive patients with NVAF (36 cases of paroxysmal atrial fibrillation and 45 cases of persistent atrial fibrillation) who were planned to undergo catheter radiofrequency ablation were enrolled. All patients were examined by transthoracic echocardiography (TTE), TEE, and computed tomography angiography (CTA) before surgery. The LAA orifice area was obtained according to the images of CTA. According to the left atrial appendage morphology, it was divided into chicken wing type and non-chicken wing type. At the same time, TEE was performed to determine left atrial appendage flow velocity (LAAFV), and the relationship between the left atrial appendage orifice area and LAAFV was analyzed.
RESULTS
The LAAFV in Non-chicken wing group was lower than that in Chicken wing group (36.2 ± 15.0 cm/s vs. 49.1 ± 22.0 cm/s, p-value < 0.05). In the subgroup analysis, the LAAFV in Non-chicken wing group was lower than that in Chicken wing group in the paroxysmal AF (44.0 ± 14.3 cm/s vs. 60.2 ± 22.8 cm/s, p-value < 0.05). In the persistent AF, similar results were observed (29.7 ± 12.4 cm/s vs. 40.8 ± 17.7 cm/s, p-value < 0.05). The LAAFV in persistent AF group was lower than that in paroxysmal AF group (34.6 ± 15.8 cm/s vs. 49.9 ± 20.0 cm/s, p-value < 0.001). The LAAFV was negatively correlated with left atrial dimension (R = - 0.451, p-value < 0.001), LAA orifice area (R= - 0.438, p-value < 0.001) and left ventricular mass index (LVMI) (R= - 0.624, p-value < 0.001), while it was positively correlated with LVEF (R = 0.271, p-value = 0.014). Multiple linear regression analysis showed that LAA morphology (β = - 0.335, p-value < 0.001), LAA orifice area (β = - 0.185, p-value = 0.033), AF type (β = - 0.167, p-value = 0.043) and LVMI (β = - 0.465, p-value < 0.001) were independent factors of LAAFV.
CONCLUSIONS
The LAA orifice area is closely related to the mechanical function of the LAA in patients with NVAF. The larger LAA orifice area and LVMI, Non-chicken wing LAA and persistent AF are independent predictors of decreased mechanical function of LAA, and these parameters might be helpful for better management of LA thrombosis.
Topics: Atrial Appendage; Atrial Fibrillation; Blood Flow Velocity; COVID-19; Catheter Ablation; China; Computed Tomography Angiography; Echocardiography; Female; Heart Atria; Humans; Image Processing, Computer-Assisted; Imaging, Three-Dimensional; Infection Control; Male; Middle Aged; Organizational Innovation; Preoperative Care; Risk Adjustment; SARS-CoV-2; Thromboembolism
PubMed: 34530731
DOI: 10.1186/s12872-021-02242-9 -
Computers in Biology and Medicine Sep 2023Disruptions to left atrial (LA) blood flow, such as those caused by atrial fibrillation (AF), can lead to thrombosis in the left atrial appendage (LAA) and an increased...
Disruptions to left atrial (LA) blood flow, such as those caused by atrial fibrillation (AF), can lead to thrombosis in the left atrial appendage (LAA) and an increased risk of systemic embolism. LA hemodynamics are influenced by various factors, including LA anatomy and function, and pulmonary vein (PV) inflow conditions. In particular, the PV flow split can vary significantly among and within patients depending on multiple factors. In this study, we investigated how changes in PV flow split affect LA flow transport, focusing for the first time on blood stasis in the LAA, using a high-fidelity patient-specific computational fluid dynamics (CFD) model. We use an Immersed Boundary Method, simulating the flow in a fixed, uniform Cartesian mesh and imposing the movement of the LA walls with a moving Lagrangian mesh generated from 4D Computerized Tomography images. We analyzed LA anatomies from eight patients with varying atrial function, including three with AF and either a LAA thrombus or a history of Transient Ischemic Attacks (TIAs). Using four different flow splits (60/40% and 55/45% through right and left PVs, even flow rate, and same velocity through each PV), we found that flow patterns are sensitive to PV flow split variations, particularly in planes parallel to the mitral valve. Changes in PV flow split also had a significant impact on blood stasis and could contribute to increased risk for thrombosis inside the LAA, particularly in patients with AF and previous LAA thrombus or a history of TIAs. Our study highlights the importance of considering patient-specific PV flow split variations when assessing LA hemodynamics and identifying patients at increased risk for thrombosis and stroke. This knowledge is relevant to planning clinical procedures such as AF ablation or the implementation of LAA occluders.
Topics: Humans; Atrial Appendage; Atrial Fibrillation; Pulmonary Veins; Heart Atria; Hemodynamics
PubMed: 37352639
DOI: 10.1016/j.compbiomed.2023.107128 -
Arquivos Brasileiros de Cardiologia Feb 2021Atrial fibrillation is the most common persistent arrhythmia, and is the main factor that leads to thromboembolism.
BACKGROUND
Atrial fibrillation is the most common persistent arrhythmia, and is the main factor that leads to thromboembolism.
OBJECTIVE
To investigate the value of left atrial diameter combined with CHA2DS2-VASc score in predicting left atrial/left atrial appendage thrombosis in non-valvular atrial fibrillation.
METHODS
This is a retrospective study. 238 patients with non-valvular atrial fibrillation were selected and divided into two groups: thrombosis and non-thrombosis. CHA2DS2-VASc score was determined. P<0.05 was considered statistically significant.
RESULTS
Multivariate logistic regression analysis revealed that the history of stroke/transient ischemic attack, vascular disease, CHA2DS2-VASc score, left atrial diameter (LAD), left ventricular end-diastolic dimension (LVEDD) and left ventricular ejection fraction (LVEF) were independent risk factors for left atrial/left atrial appendage thrombosis (p<0.05). Receiver operating characteristic curve analysis revealed that the area under the curve for the CHA2DS2-VASc score in predicting left atrial/left atrial appendage thrombosis was 0.593 when the CHA2DS2-VASc score was ≥3 points, and sensitivity and specificity were 86.5% and 32.6%, respectively, while the area under the curve for LAD in predicting left atrial/left atrial appendage thrombosis was 0.786 when LAD was ≥44.17 mm, and sensitivity and specificity were 89.6% and 60.9%, respectively. Among the different CHA2DS2-VASc groups, the incidence rate of left atrial/left atrial appendage thrombosis in patients with LAD ≥44.17 mm was higher than patients with LAD <44.17 mm (p<0.05).
CONCLUSION
CHA2DS2-VASc score and LAD are correlated with left atrial/left atrial appendage thrombosis in non-valvular atrial fibrillation. For patients with a CHA2DS2-VASc score of 0 or 1, when LAD is ≥44.17 mm, the risk for left atrial/left atrial appendage thrombosis remained high. (Arq Bras Cardiol. 2020; [online].ahead print, PP.0-0).
Topics: Atrial Appendage; Atrial Fibrillation; Humans; Retrospective Studies; Risk Assessment; Risk Factors; Stroke; Stroke Volume; Thrombosis; Ventricular Function, Left
PubMed: 33470330
DOI: 10.36660/abc.20190492