Is CHA2DS2-VASc score a predictor of left atrial thrombus in patients with paroxysmal atrial fibrillation?

Two-dimensional speckle tracking imaging analyses of the correlations between left atrial appendage function and stroke risk in nonvalvular atrial fibrillation patients

Stroke incidence is the most severe complication associated with atrial fibrillation (AF), and the most common site of thrombus formation in AF patients is the left atrial appendage (LAA). This study was developed to use two-dimensional speckle tracking imaging (2D-STI) to explore associations between LAA strain/strain rate and stroke incidence and to evaluate the value of utilizing LAA strain and strain rate values to support the stratification of nonvalvular AF (NVAF) patients based on stroke risk. A total of 486 AF patients who had undergone transesophageal echocardiography to exclude potential intracardiac thrombosis between March 2021 and November 2022 were consecutively enrolled. Patients meeting the inclusion criteria were separated into two groups according to their history of stroke/transient ischemic attack (TIA). LAA strain and strain rate values in these patients were measured via 2D-STI. Multivariable logistic regression analysis was employed to determine independent risk factors for the construction of a combined predictive model. Of the 333 analyzed patients (134 females, aged 65 (56,72) years), 39 (11.71%, 39/333) had a history of stroke at the time of evaluation. Multivariate logistic regression analysis demonstrated that nonparoxysmal AF, CHA2DS2VASc score, LAA thrombus/spontaneous echo contrast (SEC), LAA strain, and strain rate were all predictors of stroke incidence among NVAF patients. The combined predictive model demonstrated excellent discriminative ability, with an AUC of 0.91 (95%CI 0.87-0.95, P < 0.001), and a sensitivity and specificity of 79.49% and 89.46%, respectively. The Hosmer-Lemeshow test confirmed good calibration, yielding a value of 0.98. Comparative decision curve analysis showed that the model provided superior net benefits compared to the CHA2DS2VASc score. Furthermore, the model exhibited improved predictive performance and reclassification for stroke when compared to the CHA2DS2VASc score (AUC 0.91 vs. 0.88, Z = 2.32, P = 0.02), accompanied by a significant increase in the net reclassification index (+ 5.44%, P < 0.001) and integrated discrimination improvement (8.21%, P < 0.001). These data demonstrate that LAA strain and strain rate, as measured via 2D-STI, can offer value when assessing LAA function in AF patients, potentially providing further predictive value to extant clinical risk scoring strategies.

The relationship between incomplete surgical obliteration of the left atrial appendage and thromboembolic events after mitral valve surgery (from the ISOLATE Registry)

Left atrial appendage (LAA) is a common site of thrombus formation especially in patients with atrial fibrillation (AF). Complete surgical LAA closure (cSLC) is the surgical aim, however incomplete surgical LAA closure (iSLC) is not rare. In this study, we aimed to evaluate the risk of thromboembolic complications (TEC) in AF patients with iSLC after mitral valve surgery. A total of 101 AF patients (mean age: 61.8 ± 11.8 years; male:32), who underwent surgical suture ligation during mitral valve surgery were enrolled in this retrospective study. All patients underwent transthoracic and transesophageal echocardiography (TEE) at least 3 months after surgery. The primary outcome was the occurrence of TEC including any ischemic stroke, transient ischemic attack, coronary or peripheral embolism. TEE examination revealed cSLC in 66 (65.3%) and iSLC in 35 patients (34.6%). A total of 12 TECs (11.9%) occurred during a mean follow-up time of 41.1 ± 15.6 months. TECs were found to be significantly higher in the iSLC group (25.7% vs 4.5%, p = 0.002). The prevalence of iSLC was significantly higher in patients with TEC (75 vs. 29.2%, p = 0.002). High CHA₂DS₂-VASc Score and iSLC were found to be independent predictors of TEC. Long term TEC free survival was found to be significantly decreased in patients with iSLC. The presence of iSLC was associated with a significantly increased risk of TEC in AF patients after mitral valve surgery. Routine intraoperative and postoperative screening for iSLC by TEE and long-term strict anticoagulation therapy are recommended in these patients.

CHA2DS2-VASc Score as a Predictor for Left Atrial Thrombus or Spontaneous Echo Contrast in Patients with Nonvalvular Atrial Fibrillation: A Meta-Analysis

Objective

This meta-analysis aimed at exploring the predictive value of CHA₂DS₂-VASc score for the left atrial thrombus (LAT) or left atrial spontaneous echo contrast (LASEC) in patients with nonvalvular atrial fibrillation (NVAF).

Methods

PubMed, Embase, Web of Science, ScienceDirect, Cochrane Library, and Chinese core journals of the CNKI and Wanfang databases were searched to identify all the relevant papers that were published up to January 2020. The data were extracted for pooled odds ratios (ORs) with 95% confidence intervals (CIs), heterogeneity, subgroup, publication bias, and sensitivity analysis.

Results

Overall, 15 studies containing 6223 patients with NVAF were enrolled. All studies were evaluated for LAT, and 12 studies were evaluated for LASEC. The pooled analysis using a random-effects model showed that a high CHA₂DS₂-VASc score was related with LAT/LASEC (pooled OR = 1.59, 95% CI: 1.35–1.88, P < 0.001) with high heterogeneity (I² = 76.9%, P < 0.001) and LAT (pooled OR = 1.83, 95% CI: 1.44–2.33, P < 0.001) with high heterogeneity (I² = 79.4%, P < 0.001). The subgroup analysis demonstrated that the sample size may be the main source of heterogeneity. Although the Begg's funnel plot based on 15 studies for LAT/LASEC (P = 0.029) and 12 studies for LAT (P = 0.046) indicated the presence of publication bias among the included studies, the trim-and-fill method verified the stability of the pooled outcomes. In addition, sensitivity analysis indicated that all effects were stable.

Conclusion

The results of this meta-analysis showed that the CHA₂DS₂-VASc score is related with LAT and LASEC in patients with NVAF. However, more studies are warranted to address this issue.

A novel risk score for predicting left atrial and left atrial appendage thrombogenic milieu in patients with non-valvular atrial fibrillation

BACKGROUND

Although the CHADS2 and CHA2DS2-VASc scoring systems are commonly used as measures of thromboembolic risk in patients with nonvalvular atrial fibrillation (NVAF), data are inconsistent as to their value in predicting the presence of left atrial (LA) and/or left atrial appendage (LAA) thrombogenic milieu (TM). The present study aimed to establish a novel risk score to assess the risk of LA and/or LAATM in NVAF patients.

METHODS

This is a retrospective case-control study that included 125 consecutive patients with NVAF plus TM, as evidenced by transesophageal echocardiography (TEE) during a period from1 January 2010 to 1 February 2017. The controls were 1098 NVAF patients without TM during the same period. Risk factors for LA and/or LAATM were identified using univariable analysis and multivariable logistic regression. The risk score model was developed based on 10-fold validation and multiple regression. Risk model performance was evaluated using receiver operating characteristic (ROC) curves. Net reclassification improvement (NRI) was used for the comparison of C-statistics. The AUCs were compared using the Z test.

RESULTS

Among all 1223 NVAF patients, 125 (10.22%) patients had LA and/or LAATM. A score system (0-12) was developed based on the following 6 independent variables identified by 10-fold validation with sequential methods. Different points were assigned for each variable, according to multivariable regression using relative coefficients (coefficient of the index risk factor divided by the lowest coefficient among the 6 risk factors; rounded to closest integer): 1 for blood type A and N-terminal B-type natriuretic peptide (NT-proBNP) ≥864.85 pg/mL; 2 for LAD ≥43.5 mm and age ≥ 73.5 years old; 3 for previous heart failure and previous stroke or TIA. The present risk score system had a sensitivity of 58.3%, specificity of 91.4 and accuracy of 81.6%. The area under the ROC curve (AUC) was 0.832, (95% CI: 0.784-0.881; P < 0.001). The negative predictive value (NPV) was 92% when we set the cut-off point at 4; when the cut-off point was set at 8, the positive predictive value (PPV) was 85.7%. Compared with CHADS2 and CHA2DS2-VASc score, the present novel risk score has better predictive power [net reclassification improvement (NRI) +96.3% and +66.2%, respectively; all P < 0.001].

CONCLUSION

This study developed a novel risk score to help predicting LA and/or LAATM in NVAF patients, which had higher accuracy than CHADS2 and CHA2DS2-VASc score system.

Diagnosis and Management of Left Atrium Appendage Thrombosis in Atrial Fibrillation Patients Undergoing Cardioversion

Atrial fibrillation is the most common cardiac arrhythmia and is associated with an increased risk of stroke and thromboembolic complications. A rhythm control strategy with both electrical and pharmacological cardioversion is recommended for patients with symptomatic atrial fibrillation. Anticoagulant therapy for 3–4 weeks prior to cardioversion is recommended in order to avoid thromboembolic events deriving from restoring sinus rhythm. Transesophageal echocardiography has a pivotal role in this setting, excluding the presence of left atrial appendage thrombus before cardioversion. The aim of this review is to discuss the epidemiology and risk factors for left atrial appendage thrombosis, the role of echocardiography in the decision making before cardioversion, and the efficacy of different anticoagulant regimens on the detection and treatment of left atrial appendage thrombosis.

Incidence and Predictors of Intracardiac Thrombus on Pre-electrophysiological Procedure Transesophageal Echocardiography

Background

Cerebral thromboembolism is a potentially devastating complication of atrial fibrillation (AF) and atrial flutter (AFl). The use of transesophageal echocardiogram (TEE) before electrophysiological procedures in anticoagulated patients is variable. Our objective was to determine the incidence and identify predictors of intracardiac left atrial appendage (LAA) thrombus on TEE in patients with AF/AFl before electrical cardioversion or ablation.

Methods

We reviewed TEEs of 401 patients undergoing an electrical cardioversion, AF, or AFl ablation from April 2013 to September 2015 at the McGill University Health Center. Clinical and echocardiographic variables were collected at the time of the TEE and follow-up visits. Multivariate logistic regression was used to determine predictors of LAA thrombus.

Results

Of 401 patients, 11.2% had LAA thrombus on TEE. The majority (87%) of patients were anticoagulated for at least 3 weeks before the TEE. The incidence of LAA thrombus was 21% (23/110) in patients taking warfarin vs 6.4% (15/236) in patients taking direct oral anticoagulants. Multivariate analysis identified prior stroke (odds ratio [OR], 2.7; 95% confidence interval [CI], 1.1-6.9) and heart failure (OR, 2.2; 95% CI, 1.0-4.7) as predictors of thrombus, whereas direct oral anticoagulant use (OR, 0.4; 95% CI, 0.2-0.8) was associated with reduced odds of thrombus.

Conclusions

LAA thrombus was identified in a significant proportion of patients undergoing TEE before cardioversion or ablation of AF/AFl despite preprocedural anticoagulation. Patients at increased risk of LAA thrombus (heart failure and prior stroke) may benefit from TEE before cardioversion, AF, or AFl ablation.

ABO blood groups: A risk factor for left atrial and left atrial appendage thrombogenic milieu in patients with non-valvular atrial fibrillation

BACKGROUND

Previous studies have identified ABO blood groups as predictors of thromboembolic diseases. In patients with atrial fibrillation (AF), however, potential association between ABO blood groups and the risk of left atrial (LA) and/or left atrial appendage (LAA) thrombogenic milieu (TM) has not been established.

METHODS

This is a retrospective case-control study that included 125 consecutive patients with non-valvular atrial fibrillation (NVAF) plus TM, as evidenced by transesophageal echocardiography (TEE) during a period from1 January 2010 to 31 December 2016. The controls were selected randomly from 1072 NVAF without TM at a 1:2 ratio. Potential association between ABO blood groups and TM was analyzed using multivariate logistic regression analysis.

RESULTS

The risk of TM was higher in patients with blood group A (33.6% vs. 20.2% in non-A blood groups, P=0.005). After adjusting for age, sex, oral anticoagulant use, AF type and duration, and relevant functional measures (e.g., NT-pro BNP level, left atrium diameter, and left ventricular ejection fraction), blood group A remained associated with an increased risk of TM (OR=2.99, 95% CI 1.4-6.388, P=0.005).

CONCLUSION

Blood group A is an independent risk factor for TM in NVAF patients.

Left atrial thrombi and spontaneous echo contrast in patients with atrial fibrillation : Systematic analysis of a single-center experience

BACKGROUND

Atrial fibrillation is associated with a high risk for thromboembolic events. Thrombi in the left atrial appendage and spontaneous echo contrast (SEC) correlate positively with this embolic risk. We studied the laboratory, echocardiographic, and epidemiologic parameters that could predict left atrial thrombi and the intensity of the SEC.

PATIENTS AND METHODS

Between September 2013 and June 2015 we included 372 patients with atrial fibrillation before planned electrical cardioversion (transesophageal-guided strategy) in this study. After assessing the risk of stroke and bleeding (CHA₂DS₂-VASc and HAS-BLED scores), we measured the concentration of the D-dimer and B-type natriuretic peptide at the time of the transesophageal echocardiography as well as the left atrial volume and the ejection fraction during transthoracic echocardiography.

RESULTS

The ejection fraction and the CHA₂DS₂-VASc score were identified as independent predictors of both left atrial thrombi and SEC, whereas the left atrial volume could only predict the intensity of SEC. In contrast to the results of other studies, the biomarkers in this study failed to predict the outcome.

CONCLUSION

Only the echocardiographic and epidemiologic parameters were predictors of left atrial thrombi and SEC intensity, while the studied biomarkers had no predictive power. Using clinical data and transthoracic echocardiography, we can change the therapeutic strategy in high-risk patients.

Prevalence of left atrial thrombus in patients with non-valvular atrial fibrillation. A systematic review and meta-analysis of the literature

We performed a meta-analysis about the prevalence of left atrial thrombus (LAT) in patients with atrial fibrillation (AF) undergoing trans-esophageal echocardiography (TEE). Studies reporting on LAT presence in AF patients were systematically searched in the PubMed, Web of Science, Scopus and EMBASE databases and the pooled LAT prevalence was evaluated as weighted mean prevalence (WMP). Seventy-two studies (20,516 AF patients) showed a LAT WMP of 9.8 % (95 %CI: 7.6 %-12.5 %). LAT presence was associated with a higher age (mean difference: 2.56, 95 %CI: 1.49-3.62), and higher prevalence of female gender (OR: 1.35, 95 %CI: 1.04-1.75), hypertension (OR: 1.78, 95 %CI: 1.38-2.30), diabetes mellitus (OR: 1.86, 95 %CI: 1.33-2.59) and chronic heart failure (OR: 3.67, 95 %CI: 2.40-5.60). Overall, LAT patients exhibited a higher CHADS2-score (mean difference 0.88, 95 %CI: 0.68-1.07) and a higher risk of stroke/systemic embolism (OR: 3.53, 95 %CI: 2.24-5.56) compared with those without LAT. A meta-regression showed an inverse association between LAT prevalence and the presence of anticoagulation (Z-value: -7.3, p< 0.001). Indeed, studies in which 100 % of patients received oral anticoagulation reported a 3.4 % WMP of LAT (95 %CI: 1.3 %-8.7 %), whereas studies in which 0 % of patients received anticoagulation showed a LAT WMP of 7.4 % (95 %CI: 2.3 %-21.5 %). Our data suggest that LAT is present in ≍10 % of AF patients, and is associated with a 3.5-fold increased risk of stroke/systemic embolism. Interestingly, LAT is also reported in some of patients receiving anticoagulation. The implementation of the screening of LAT in AF patients before cardioversion/ablation could be useful for the prevention of vascular events.

The CHA2DS2-VASc score as a predictor of left atrial thrombus in patients with non-valvular atrial fibrillation

OBJECTIVE

To investigate whether or not the CHA2DS2-VASc score predicts left atrial (LA) thrombus detected on pre-cardioversion transoesophageal echocardiography (TEE).

MATERIALS AND METHODS

The medical records of patients who had undergone TEE were reviewed to assess the presence of LA thrombus prior to direct-current cardioversion for atrial fibrillation (AF). The CHA2DS2-VASc score was calculated for each patient. Clinical TEE reports were reviewed for the presence of LA thrombus. Patients with a valve prosthesis or rheumatic mitral valve disease were excluded from this study.

RESULTS

A total of 309 patients were identified. The mean age was 70.1 ± 9.8 years and 151 (49%) patients were males and 158 (51%) were females. LA thrombus was seen in 32 (10.3%) of the 309 patients. Fifty (16.2%) patients had a low CHA2DS2-VASc score (0-1), 230 (74.4%) had an intermediate score (2-4) and 29 (9.4%) had a high score (5-9). The incidence of LA thrombus in the low, intermediate and high CHA2DS2-VASc score groups was 0, 4.4 and 68.7%, respectively. The LA thrombus risk increased with increasing CHA2DS2-VASc scores. On multivariate logistic analysis, the CHA2DS2-VASc score (OR 3.26, 95% CI 2.3-4.65; p = 0.001) and age (OR 0.93, 95% CI 0.88-0.98; p = 0.004) were independent risk factors for LA thrombus in patients with non-valvular AF.

CONCLUSION

A high CHA2DS2-VASc score was independently associated with the presence of LA thrombus in patients with non-valvular AF.

Review of atrial fibrillation outcome trials of oral anticoagulant and antiplatelet agents

Atrial fibrillation (AF) is strongly associated with cardioembolic stroke, and thromboprophylaxis is an established means of reducing stroke risk in patients with AF. Oral vitamin K antagonists such as warfarin have been the mainstay of therapy for stroke prevention in patients with AF. However, they are associated with a number of limitations, including excessive bleeding when not adequately controlled. Antiplatelet agents do not match vitamin K antagonists in terms of their preventive efficacy. Dual-antiplatelet therapy (clopidogrel and acetylsalicylic acid) or combined antiplatelet-vitamin K antagonist therapy in AF has also failed to provide convincing evidence of their additional benefit over vitamin K antagonists alone. Novel oral anticoagulants, including the direct thrombin inhibitor dabigatran and direct Factor Xa inhibitors such as rivaroxaban, apixaban, and edoxaban, have now been approved or are currently in late-stage clinical development in AF. These newer agents may provide a breakthrough in the optimal management of stroke risk.

Usefulness of transesophageal echocardiography to confirm clinical utility of CHA2DS2-VASc and CHADS2 scores in atrial flutter

The CHA(2)DS(2)-VASc and CHADS(2) risk stratification schemes are used to predict thromboembolism and ischemic stroke in patients with atrial fibrillation. However, limited data are available regarding the utility of these risk stratification schemes for stroke in patients with atrial flutter. A retrospective analysis of 455 transesophageal echocardiographic studies in patients with atrial flutter was performed to identify left atrial (LA) thrombi and/or spontaneous echocardiographic contrast (SEC). The CHA(2)DS(2)-VASc (Congestive heart failure, Hypertension, Age ≥75 years [doubled risk weight], Diabetes mellitus, previous Stroke/transient ischemic attack [doubled risk weight], Vascular disease, Age 65 to 74 years, Sex) and CHADS(2) (Congestive heart failure, Hypertension, Age ≥75 years, Diabetes mellitus, previous Stroke/transient ischemic attack [double risk weight]) scores were calculated to stratify the risk of stroke or transient cerebrovascular ischemic events. Transesophageal echocardiography revealed LA thrombi in 5.3% and SEC in 25.9% of patients. Using CHADS(2), LA thrombus was found in 2.2% of the low-intermediate-risk group and 8.3% of the high-risk group (p = 0.005). SEC was found in 19.8% of the low-intermediate-risk group and 32% of the high-risk group (p = 0.004). Using CHA(2)DS(2)-VASc, LA thrombus was found in 1.7% of the low-intermediate-risk group and 6.5% of the high-risk group (p = 0.053). SEC was found in 11.8% of the low-intermediate-risk group versus 30.9% of the high-risk group (p = 0.004). The sensitivity for LA thrombus/SEC with a high CHADS(2) and CHA(2)DS(2)-VASc score was 64.8% and 88.7%, respectively (p = 0.0001). The specificity for LA thrombus/SEC with high CHADS(2) and CHA(2)DS(2)-VASc scores was 52.6% and 28.9%, respectively (p = 0.0001). In conclusion, both CHA(2)DS(2)-VASc and CHADS(2) scores are useful for stroke risk stratification in patients with atrial flutter. CHA(2)DS(2)-VASc had greater sensitivity for LA thrombus and SEC detection at the cost of reduced specificity.

Early neurological outcomes according to CHADS2 score in stroke patients with non-valvular atrial fibrillation

BACKGROUND AND PURPOSE

A higher CHADS(2) score or CHA(2)DS(2)-VASc score is associated with an increased risk of ischaemic stroke in patients with non-valvular atrial fibrillation (NVAF). However, there are no data regarding early neurological outcomes after stroke according to the risk levels.

METHODS

In this study, a total of 649 stroke patients with NVAF were enrolled and categorized into three groups: low-risk (CHADS(2) score of 0-1), moderate-risk (CHADS(2) score 2-3), or high-risk group (CHADS(2) score ≥4). CHA(2)DS(2)-VASc score was divided into four groups including 0-1, 2-3, 4-5, and ≥6. We investigated whether there were differences in initial stroke severity, early neurological outcome, and infarct size according to CHADS(2) score or CHA(2)DS(2)-VASc score in stroke patients with NVAF.

RESULTS

The initial National Institutes of Health Stroke Scale (NIHSS) score was highest in high-risk group [9.5, interquartile range (IQR) 4-18], followed by moderate-risk (8, IQR 2-17) and low-risk group (6, IQR 2-15) (P=0.012). Likewise, initial stroke severity increased in a positive fashion with increasing the CHA(2)DS(2)-VASc score. During hospitalization, those in the high-risk group or higher CHA(2)DS(2)-VASc score had less improvement in their NIHSS score. Furthermore, early neurological deterioration (END) developed more frequently as CHADS(2) score or CHA(2)DS(2)-VASc score increased. Multivariate analysis showed being in the high-risk group was independently associated with END (OR 2.129, 95% CI 1.013-4.477).

CONCLUSIONS

Our data indicate that patients with NVAF and higher CHADS(2) score or CHA(2)DS(2)-VASc score are more likely to develop severe stroke and a worse clinical course is expected in these patients after stroke presentation.