Transesophageal echocardiography measures left atrial appendage volume and function and predicts recurrence of paroxysmal atrial fibrillation after radiofrequency catheter ablation

An effective prediction model based on XGBoost for the 12-month recurrence of AF patients after RFA

BACKGROUND

Atrial fibrillation (AF) is a common heart rhythm disorder that can lead to complications such as stroke and heart failure. Radiofrequency ablation (RFA) is a procedure used to treat AF, but it is not always successful in maintaining a normal heart rhythm. This study aimed to construct a clinical prediction model based on extreme gradient boosting (XGBoost) for AF recurrence 12 months after ablation.

METHODS

The 27-dimensional data of 359 patients with AF undergoing RFA in the First Affiliated Hospital of Soochow University from October 2018 to November 2021 were retrospectively analysed. We adopted the logistic regression, support vector machine (SVM), random forest (RF) and XGBoost methods to conduct the experiment. To evaluate the performance of the prediction, we used the area under the receiver operating characteristic curve (AUC), the area under the precision-recall curve (AP), and calibration curves of both the training and testing sets. Finally, Shapley additive explanations (SHAP) were utilized to explain the significance of the variables.

RESULTS

Of the 27-dimensional variables, ejection fraction (EF) of the left atrial appendage (LAA), N-terminal probrain natriuretic peptide (NT-proBNP), global peak longitudinal strain of the LAA (LAAGPLS), left atrial diameter (LAD), diabetes mellitus (DM) history, and female sex had a significant role in the predictive model. The experimental results demonstrated that XGBoost exhibited the best performance among these methods, and the accuracy, specificity, sensitivity, precision and F1 score (a measure of test accuracy) of XGBoost were 86.1%, 89.7%, 71.4%, 62.5% and 0.67, respectively. In addition, SHAP analysis also proved that the 6 parameters were decisive for the effect of the XGBoost-based prediction model.

CONCLUSIONS

We proposed an effective model based on XGBoost that can be used to predict the recurrence of AF patients after RFA. This prediction result can guide treatment decisions and help to optimize the management of AF.

Impact of pre-ablation left appendage flow velocities on long term recurrence of catheter ablation for paroxysmal atrial fibrillation

BACKGROUND

Despite undergoing a single ablation, many patients with paroxysmal atrial fibrillation (PAF) experience a gradually increasing recurrence rate. This study aims to examine the relationship between left atrial appendage emptying velocity (LAAeV) and filling velocity (LAAfV) profiles and 3-year recurrence of AF after ablation.

METHODS

We conducted a prospective study of 658 consecutive PAF patients who underwent their first ablation between January 2018 and December 2019. We collected the clinical and echocardiographic characteristics of the patients. LAAeV and LAAfV were obtained from a transesophageal echocardiogram (TEE) before catheter ablation. Patients were followed at regular intervals to monitor for the primary outcome of AF recurrence.

RESULTS

After a median follow-up period of 35.3 months (range, 10.7-36.3), 288 patients (43.8%) experienced AF recurrence after catheter ablation. Patients who experienced AF recurrence had decreased LAAeV and LAAfV (LAAeV: 56.5 ± 21.2 vs. 59.6 ± 20.7 cm/s, p = .052; LAAfV: 47.5 ± 17.9 vs. 51.7 ± 18.2, p = .003). Kaplan-Meier analysis showed that patients in the low LAAeV (<55 cm/s) group had a poorer event-free survival rate than those in the high LAAeV (≥55 cm/s) group (log-rank p = .012). Patients with LAAfV <48 cm/s had a significantly higher risk of AF recurrence than those with LAAfV ≥48 cm/s (log-rank p = .003). In the multivariable model, low LAAfV pre-ablation in TEE-guided was significantly independently associated with 3-year recurrence after single radiofrequency ablation in patients with PAF, along with LA dimension and duration of AF.

CONCLUSION

This study found an independent association between low LAAfV pre-ablation in TEE-guided and 3-year recurrence after single radiofrequency ablation in patients with PAF.

Comparison of left atrial and left atrial appendage mechanics in the recurrence of atrial fibrillation after radiofrequency catheter ablation

OBJECTIVES

Although radiofrequency catheter ablation (RFCA) has become an important treatment strategy for paroxysmal or persistent atrial fibrillation (AF), AF recurrence after RFCA remains an important issue that plagues clinicians and patients. This study aimed to investigate the association of left atrial (LA) and left atrial appendage (LAA) mechanics with AF recurrence after RFCA and to compare their prognostic values in patients with AF undergoing RFCA.

METHODS

A total of 160 patients with non-valvular AF who underwent RFCA for the first time were included in this study. All patients underwent transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE) before the procedure. All patients were followed up for one year after RFCA, and AF recurrence was recorded. Speckle-tracking echocardiography was used to measure LA and LAA global longitudinal strain (GLS). LA and LAA mechanical dispersion (MD) were defined as the standard deviation of time to peak strain at each segment standardized by the R-R interval. Logistic regression analysis was used to analyze independent contributors for AF recurrence after RFCA. The prediction efficiency of factors associated with the presence of AF recurrence was evaluated by the receiver operating characteristic (ROC) curve with area under curve (AUC).

RESULTS

During 1-year follow-up, 45 (28%) patients had recurrence, and 115 (72%) patients had no recurrence. The age, CHA2 DS2 -VASc score, NT-proBNP, LA volume index (LAVI), LA MD, and LAA MD of patients in recurrence group were significantly higher than those in no recurrent group (p < .05). The LAA emptying fraction (LAAEF), LA GLS, and LAA GLS in recurrence group were significantly lower than those in no recurrent group (p < .05). Logistic regression analysis showed that LA and LAA GLS were independent contributors for AF recurrence (p < .05), providing incremental values. The AUCs of LA and LAA GLS in predicting AF recurrence were higher than that of other factors, and the LA GLS+LAA GLS joint model had higher prediction efficiency.

CONCLUSION

This study demonstrated the LA and LAA GLS were independent contributors for AF recurrence after RFCA and provided incremental values. LA and LAA GLS can be used as the predictor of AF recurrence after RFCA, and they may be beneficial for the risk stratification of AF recurrence.

Incremental predictive utility of a radiomics signature in a nomogram for the recurrence of atrial fibrillation

Background

Recurrence of atrial fibrillation (AF) after catheter ablation (CA) remains a challenge today. Although it is believed that evaluating the structural and functional remodeling of the left atrium (LA) may be helpful in predicting AF recurrence, there is a lack of consensus on prediction accuracy. Ultrasound-based radiomics is currently receiving increasing attention because it might aid in the diagnosis and prognosis prediction of AF recurrence. However, research on LA ultrasound radiomics is limited.

Objective

We aim to investigate the incremental predictive utility of LA radiomics and construct a radiomics nomogram to preoperatively predict AF recurrence following CA.

Methods

A training cohort of 232 AF patients was designed for nomogram construction, while a validation cohort (n = 100) served as the model performance test. AF recurrence during a follow-up period of 3-12 months was defined as the endpoint. The radiomics features related to AF recurrence were extracted and selected to create the radiomics score (rad score). These rad scores, along with other morphological and functional indicators for AF recurrence, were included in the multivariate Cox analysis to establish a nomogram for the prediction of the likelihood of AF recurrence within 1 year following CA.

Results

In the training and validation cohorts, AF recurrence rates accounted for 32.3% (75/232) and 25.0% (25/100), respectively. We extracted seven types of radiomics features associated with AF recurrence from apical four-chamber view echocardiography images and established a rad score for each patient. The radiomics nomogram was built with the rad score, AF type, left atrial appendage emptying flow velocity, and peak atrial longitudinal strain. It outperformed the nomogram building without the rad score in terms of the predictive efficacy of CA outcome and showed favorable performance in both cohorts.

Conclusion

We revealed the incremental utility of a radiomics signature in the prediction of AF recurrence and preliminarily developed and validated a radiomics nomogram for identifying patients who were at high risk of post-CA recurrence, which contributed to an appropriate management strategy for AF.

Clinical features of ischemic stroke in patients with nonvalvular atrial fibrillation combined with intracranial atherosclerotic stenosis

BACKGROUND

Nonvalvular atrial fibrillation (NVAF) and intracranial atherosclerotic stenosis (ICAS) are major causes of ischemic stroke. Relatively few studies have focused on the risk factors and clinical features of ischemic stroke caused by NVAF combined with ICAS.

METHOD

We retrospectively evaluated NVAF and/or ICAS in patients with acute ischemic stroke admitted within 72 h after stroke. All patients with acute ischemic stroke underwent diffusion-weighted magnetic resonance imaging (DWI), magnetic resonance angiography (MRA), computed tomography angiography (CTA), and/or digital subtraction angiography (DSA). NVAF was detected by routine electrocardiogram or 24-h Holter examination, Doppler echocardiography, and contrast echocardiography of the right heart.

RESULTS

Among the 635 enrolled patients, NVAF, ICAS, and NVAF+ICAS were diagnosed in 170 (26.77%), 255 (40.16%), and 210 (33.07%) patients, respectively. Patients in the NVAF+ICAS group were older (p < .001), specifically aged ≥75 years (p < .001). The admission time of the NVAF+ICAS group was shorter (p < .001) than that of the ICAS group. The admission NIHSS score of the NVAF group was higher than that of the NVAF+ICAS group (p < .001). HsCRP, NTpro-BNP, and LEVF levels were significantly different among the three groups (p < .001). NVAF+ICAS ischemic stroke occurred mainly in the right hemisphere (52.4%).

CONCLUSION

NVAF with ICAS ischemic stroke is more likely to occur in older patients. Infarctions occurred mainly in the right cerebral hemisphere. Neurological deficits in NVAF are more severe than those in NVAF combined with ICAS and in simple ICAS ischemic strokes. HsCRP, LEVF, andNTpro-BNP seem to be closely associated with NVAF+ICAS ischemic stroke.

Left atrial appendage morphofunctional indices could be predictive of arrhythmia recurrence post-atrial fibrillation ablation: a meta-analysis

BACKGROUND

Left atrium changes are implicated in atrial fibrillation (AF) substrate and are predictive of AF outcomes. Left atrial appendage (LAA) is an integral component of left atrial structure and could be affected by atrial cardiomyopathy. We aimed to elucidate the association between LAA indices and late arrhythmia recurrence after atrial fibrillation catheter ablation (AFCA).

METHODS

The MEDLINE database, ClinicalTrials.gov, medRxiv and Cochrane Library were searched for studies evaluating LAA and late arrhythmia recurrence in patients undergoing AFCA. Data were pooled by meta-analysis using a random-effects model. The primary endpoint was pre-ablation difference in LAA anatomic or functional indices.

RESULTS

A total of 34 studies were found eligible and five LAA indices were analyzed. LAA ejection fraction and LAA emptying velocity were significantly lower in patients with AF recurrence post-ablation [SMD = - 0.66; 95% CI (- 1.01, - 0.32) and SMD = - 0.56; 95% CI (- 0.73, - 0.40) respectively] as compared to arrhythmia free controls. LAA volume and LAA orifice area were significantly higher in patients with AF recurrence post-ablation (SMD = 0.51; 95% CI 0.35-0.67, and SMD = 0.35; 95% CI 0.20-0.49, respectively) as compared to arrhythmia free controls. LAA morphology was not predictive of AF recurrence post-ablation (chicken wing morphology; OR 1.27; 95% CI 0.79-2.02). Moderate statistical heterogeneity and small case-control studies are the main limitations of our meta-analysis.

CONCLUSIONS

Our findings suggest that LAA ejection fraction, LAA emptying velocity, LAA orifice area and LAA volume differ between patients suffering from arrhythmia recurrence post-ablation and arrhythmia free counterparts, while LAA morphology is not predictive of AF recurrence.

Development and Validation of a Novel Prognostic Tool to Predict Recurrence of Paroxysmal Atrial Fibrillation after the First-Time Catheter Ablation: A Retrospective Cohort Study

There is no gold standard to tell frustrating outcomes after the catheter ablation of paroxysmal atrial fibrillation (PAF). The study aims to construct a prognostic tool. We retrospectively analyzed 315 patients with PAF who underwent first-time ablation at the Second Xiangya Hospital of Central South University. The endpoint was identified as any documented relapse of atrial tachyarrhythmia lasting longer than 30 s after the three-month blanking period. Univariate Cox regression analyzed eleven preablation parameters, followed by two supervised machine learning algorithms and stepwise regression to construct a nomogram internally validated. Five factors related to ablation failure were as follows: female sex, left atrial appendage emptying flow velocity ≤31 cm/s, estimated glomerular filtration rate <65.8 mL/(min·1.73 m²), P wave duration in lead aVF ≥ 120 ms, and that in lead V1 ≥ 100 ms, which constructed a nomogram. It was correlated with the CHA₂DS₂-VASc score but outperformed the latter evidently in discrimination and clinical utility, not to mention its robust performances in goodness-of-fit and calibration. In addition, the nomogram-based risk stratification could effectively separate ablation outcomes. Patients at risk of relapse after PAF ablation can be recognized at baseline using the proposed five-factor nomogram.

Left Atrial Appendage Volume Predicts Atrial Fibrillation Recurrence after Radiofrequency Catheter Ablation: A Meta-Analysis

BACKGROUND

The influence of left atrial appendage volume (LAAV) on the recurrence of atrial fibrillation (AF) following radiofrequency catheter ablation remains unclear.

OBJECTIVES

We performed a meta-analysis to assess whether LAAV is an independent predictor of AF recurrence following radiofrequency catheter ablation.

METHODS

The PubMed and the Cochrane Library databases were searched until March 2022 to identify publications evaluating LAAV in association with AF recurrence after radiofrequency catheter ablation. Seven studies that fulfilled the specified criteria of our analysis were found. We used the Newcastle-Ottawa Scale to evaluate the quality of the studies. The pooled effects were evaluated depending on standardized mean differences (SMDs) or hazard ratios (HRs) with 95% confidence intervals (CIs). P values < 0.05 were considered statistically significant.

RESULTS

A total of 1017 patients from 7 cohort studies with a mean follow-up 16.3 months were included in the meta-analysis. Data from 6 studies (943 subjects) comparing LAAV showed that the baseline LAAV was significantly higher in patients with AF recurrence compared to those without AF (SMD: -0.63; 95% CI: -0.89 to -0,37; all p values < 0.05; I2= 62.6%). Moreover, higher LAAV was independently associated with a significantly higher risk of AF recurrence after radiofrequency catheter ablation (HR: 1.10; 95% CI: 1.02 to 1.18).

CONCLUSIONS

The meta-analysis showed that there is a significant correlation between LAAV and AF recurrence after radiofrequency catheter ablation, and the role of LAAV in AF patients should not be ignored in clinical practice.

A prediction model based on functional mitral regurgitation for the recurrence of paroxysmal atrial fibrillation (PAF) after post-circular pulmonary vein radiofrequency ablation (CPVA)

AIM

To construct a prediction model based on functional mitral regurgitation (FMR) in patients with paroxysmal atrial fibrillation (PAF) to predict atrial fibrillation recurrence after the post-circular pulmonary vein radiofrequency ablation (CPVA).

METHODS

We retrospectively analyzed 289 patients with PAF who underwent CPVA for the first time. The patients were randomly divided into modeling group and verification group at the ratio of 75:25. In the modeling group, the multivariate logistic regression was used to analyze and construct a prediction model for post-CPVA recurrence in PAF patients, which was then validated in the verification group.

RESULTS

(1) After 3-6 months of follow-up, the patients were divided into sinus rhythm group (252 cases) and recurrence group (24 cases); (2) In the modeling group, the age, left atrial diameter (LAD), and the degree of MR (mild, moderate, severe) were higher in recurrence group than that of the sinus rhythm group, and the left atrial appendage emptying velocity (LAAV) was lower in recurrence group (all p < .05). (3) A model for predicting the recurrence of PAF after radiofrequency ablation was constructed in the modeling group. The equation was: Logit(P) = -3.253 + .092 × age + 1.263 × mild MR + 2.325 × moderate MR + 5.111 × severe MR -.113 × LAAV. The area under the curve (AUC) of the model was .889 in modeling group and .866 in verification group, and the difference was not statistically significant (p > .05).

CONCLUSION

The prediction model of atrial fibrillation (AF) recurrence after CPVA in PAF patients has good predictive efficacy, specificity, and accuracy.

Left atrial appendage function and structure predictors of recurrent atrial fibrillation after catheter ablation: A meta-analysis of observational studies

Background

The results of studies evaluating the left atrial appendage (LAA) function and structure as predictors of atrial fibrillation (AF) recurrence after catheter ablation (CA) are contradictory. Therefore, we performed a meta-analysis to assess whether the LAA function and structure can predict the recurrence of AF after CA.

Methods

The PubMed, EMBASE, Web of Science, and Cochrane library databases were used to conduct a comprehensive literature search. Finally, 37 studies encompassing 11 LAA parameters were included in this meta-analysis.

Results

Compared with those in the non-recurrence group, the recurrence group had increased LAA volume (SMD 0.53, 95% CI [0.36, 0.71] p < 0.00001), LAA volume index, LAA orifice area, and LAA orifice short/long axis and decreased LAA emptying flow velocity (SMD -0.54, 95% CI [-0.68, -0.40], P < 0.00001), LAA filling flow velocity, and LAA ejection fraction, while there was no significant difference in LAA morphology or LAA depth.

Conclusion

Large LAA structure of pre-ablation (LAA volume, orifice area, orifice long/short axis, and volume index) and decreased LAA function of pre-ablation (LAA emptying flow velocity, filling flow velocity, ejection fraction, and LASEC) increase the odds of AF recurrence after CA.

Systematic review registration

[https://www.crd.york.ac.uk/prospero/], identifier [CRD42022324533].

Left atrial appendage flow velocity predicts recurrence of atrial fibrillation after catheter ablation: A systematic review and meta-analysis

Purpose

There is increasing evidence that left atrial appendage flow velocity (LAAFV) is linked to the recurrence of atrial fibrillation (AF) after catheter ablation (CA), suggesting the potential predictable significance of LAAFV in this setting. We performed a systematic review and meta-analysis to assess whether LAAFV is association with AF recurrence after CA.

Methods

Up to May 1, 2022, six databases (PubMed, EMBASE, Web of Science, Cochrane Library, Scopus, and CINAHL) were searched for literature reporting the association between LAAFV and AF recurrence after CA. All statistical analyses were carried out using STATA version 16 software. Heterogeneity was determined by the Cochrane’s Q test and I² statistics. The Newcastle-Ottawa Scale (NOS) was used to assess the methodological quality of each included study, and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) method was adopted to evaluate the quality of evidence.

Result

Sixteen studies with 5,006 AF patients after CA (1,479 patients with AF recurrence, 3,527 without AF recurrence) were included in the meta-analysis. The meta-analysis of 15 studies (16 data sets) showed that patients with recurrence exhibited lower LAAFV values than those without recurrence [standardized mean difference (SMD): −0.65, 95% CI: −0.88 to −0.42, P < 0.01]. Moreover, we evaluated the association of LAAFV and the risk of AF recurrence after CA. Nine studies (11 data sets) defined LAAFV as continuous variables, and the pooled analysis suggested that for every 1 cm/s rise in LAAFV values, the risk of AF recurrence after CA decreased by 3% [Odds Ratio (OR): 0.97, 95% CI: 0.95 to 0.99, P < 0.01]. Seven studies defined LAAFV as categorical variables, and the pooled analysis showed that lower LAAFV were associated with an increased risk of AF recurrence after CA [OR: 2.28, 95% CI: 1.46 to 3.57, P < 0.01]. The subgroup analyses showed that the association between LAAFV and AF recurrence after CA was not significantly affected by the AF type and ablation procedure. The NOS indicated that included studies were moderate to high quality, while the GRADE assessment suggested a low certainty of the evidence.

Conclusion

Lower LAAFV may be associated with an increased risk of AF recurrence after CA. Further studies with well designed and randomized studies for LAAFV should be conducted.

Systematic review registration

[https://www.crd.york.ac.uk/PROSPERO/], identifier [CRD42022333627].

The Long-Term Results of Three Catheter Ablation Methods in Patients With Paroxysmal Atrial Fibrillation: A 4-Year Follow-Up Study

Aims: Catheter ablation of paroxysmal atrial fibrillation (PAF) has been shown to be effective and safe. However, recurrence of PAF varies between 10 and 30% for radiofrequency ablation. There have been no reports comparing long-term recurrence rates following radiofrequency ablation, cryoablation, and three-dimensional guided cryoablation plus radiofrequency ablation. The aim of this study was to observe the long-term recurrence rate of PAF when treated by these three catheter ablation methods, and to explore clinical factors that can potentially predict PAF recurrence following catheter ablation. Methods: There were 238 patients involved in this study, including 106 radiofrequency (RF) ablation cases (RF group), 66 cryoablation cases (Freeze group), and 66 cases treated by three-dimensional guided cryoablation combined with radiofrequency ablation (Freeze-plus-RF group). All patients underwent standardized follow-up. The recurrence rate of atrial fibrillation (AF) in the three groups was calculated. Predictive factors for the recurrence of AF were also investigated. Results: At 48 months (the median follow-up period), the sinus rhythm maintenance rate was 77.4% in the RF group, 72.7% in the Freeze group, and 81.8% in the Freeze-plus-RF group. The maintenance rate of sinus rhythm was highest in the Freeze-plus-RF group, but differences among the three groups were not statistically significant. Further analysis found that the preoperative left atrial appendage emptying velocity (LAAEV) (recurrence vs. no recurrence, 56.58 ± 18.37 vs. 65.59 ± 18.83, respectively, p = 0.003), left atrial (LA) anteroposterior dimension (recurrence vs. no recurrence, 36.56 ± 4.65 vs. 35.00 ± 4.37, respectively; p = 0.028), and LA vertical dimension (recurrence vs. no recurrence, 56.31 ± 6.96 vs. 53.72 ± 6.52, respectively; p = 0.035) were related to postoperative recurrence. Multiple Cox regression analysis showed that only LAAEV was predictive of postoperative recurrence of PAF (hazard ratio: 0.979; 95% confidence interval: 0.961-0.997). Conclusion: Our study found that there was no statistically significant difference in long-term recurrence rates among the RF, Freeze, and Freeze-plus-RF groups. Preoperative LAAEV is an independent predictor of postoperative recurrence of PAF.

Value of Left Atrial Appendage Function Measured by Transesophageal Echocardiography for Prediction of Atrial Fibrillation Recurrence after Radiofrequency Catheter Ablation

Atrial fibrillation (AF) recurrence after radiofrequency catheter ablation (RFCA) remains a challenging issue. This study aims to explore the left atrial appendage function by transesophageal echocardiography (TEE) and assess its value in predicting AF recurrence following RFCA in paroxysmal AF patients. Eighty-one patients with paroxysmal AF that underwent RFCA were recruited. TEE was performed before ablation with the assessment of left atrial appendage emptying flow velocity (LAAeV). AF recurrence occurred in 24 patients (29.6%) within 12 months after RFCA. The left atrium diameter (LAD) and left atrium volume index (LAVI) were both significantly higher in the recurrence group compared to the non-recurrence group, while the LAAeV was significantly lower in the recurrence group. LAD, LAVi and LAAeV were univariately significant risk factors for AF recurrence after ablation. Based on receiver operating curve (ROC), LAAeV < 40.5 cm/s, LAVi > 40.5 mL and LAD > 41 mm were identified as cut-off values for predicting AF recurrence. In multivariate regression analysis LAAeV < 40.5 cm/s (HR 8.194, 95% CI 2.980–22.530, p < 0.001) was identified as the only statistically significant independent predictor of AF recurrence, as the statistical significance threshold was not achieved for LAVI > 40.5 mL and LAD > 41 mm (p = 0.319; p = 0.507, respectively). A low LAAeV was the only important independent predictor of AF recurrence within 1 year after first RFCA.

Atrial appendages’ mechanics assessed by 3D transoesophageal echocardiography as predictors of atrial fibrillation recurrence after pulmonary vein isolation

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Data on atrial appendages' mechanics as predictors of AF recurrence after PVI is scarce.

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3D and 2D-TEE have potential to provide additional data on LAA function.

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Patients with AFR had significantly lower LAA tissue velocity and ostium surface area.

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RAA tissue velocity and SVC ostium surface area were not correlated to AF recurrence.

Background

Although there are numerous studies reflecting predictors of atrial fibrillation (AF) recurrence (AFR) after pulmonary vein isolation (PVI), data on atrial appendages' mechanics is scarce. This study aimed to assess atrial appendages' mechanics by 2-dimensional (2D) and 3-dimenssional (3D) transoesphageal echocardiography (TEE) and to explore its value to predict AFR after PVI.

Methods

Consecutive patients with paroxysmal AF undergoing first PVIwere analysed. 3D and 2D-TEE with tissue Doppler imaging (TDI) and strain analysis was obtained prior to the PVI, including: left atrial appendage (LAA) TDI and strain analysis, LAA ostium surface area, right atrial appendage’s TDI velocity and superior vena cava (SVC) ostium surface area. The primary end-point was freedom from any documented recurrence of atrial arrhythmia lasting > 30 s.

Results

This single-centre, prospective study included 74 patients with paroxysmal AF (median age 59 years; 36% female; BMI 27.4 ± 4.1 kg/m², LA volume index 32 ± 11 mL/m²). After a median follow-up of 14 (IQR 10–22) months, 21 (28%) patients had AFR. In a univariate and multivariate Cox-regression analysis LAA TDI velocity (HR 1.48, 95%CI 1.28–1.62, p < 0.001) and LAA ostium surface area(HR 1.58, 95%CI 1.06–1.81, p = 0.033) both independently predicted AFR after single PVI. RAA TDI velocity and SVC ostium surface area were not correlated to AFR.

Conclusion

Paroxysmal AF patients with lower LAA TDI tissue velocity and LAA ostium surface area have higher risk of developing AFR after PVI. To our knowledge, this is the first study assessing atrial appendages’ mechanics in predicting AFR after PVI.

Clinical trial registration: www.drks.de(Identifier: DRKS00010495)

The Predictive Value of Growth Differentiation Factor-15 in Recurrence of Atrial Fibrillation after Catheter Ablation

The mechanisms underlying the recurrence of atrial fibrillation (AF) after radiofrequency catheter ablation (RFCA) are not well concerned. The study sought to explore the association between growth differentiation factor-15 (GDF-15) and the incidence of recurrent events among AF patients after the ablation procedure. We prospectively included 150 consecutive AF patients who underwent RFCA. Clinical information about the patients was collected. Blood samples on the second morning of hospital admission and three months after RFCA were collected, and enzyme-linked immunosorbent assay (ELISA) was used to measure the concentration of GDF-15. All participants were followed up at specific times (1st/3rd/6th/12th/18th/24th months) after RFCA to record recurrences events. During a median follow-up of 14.0 months, AF recurrence occurred in 37(24.7%) patients. Baseline serum GDF-15 level in the persistent AF group was significantly higher than the paroxysmal AF group [1140(854~1701)ng/L vs. 1062(651~1374)ng/L, P = 0.039]. Baseline serum GDF-15 level in the recurrence group was significantly higher than the nonrecurrence group [1287(889~1768) ng/L vs. 1062(694~1373)ng/L, P = 0.022]. Serum GDF-15 level at three months after RFCA was significantly lower than the baseline [870 (579~1270) ng/L vs. 1155 (735~1632)ng/L, P < 0.001]. The baseline GDF-15 correlated significantly with LAP (r = 0.296, P < 0.001) and LAAV(r = −0.235, P = 0.003). Kaplan-Meier analysis showed a significantly lower event-free survival time in the high baseline GDF-15 (≥1287.3 ng/L) group than the low baseline GDF-15 (<1287.3 ng/L) group (17.1 months vs. 20.4 months, Log Rank P = 0.017). In the multivariate Cox regression, baseline GDF-15(HR 1.053, 95% CI 1.007-1.100, P = 0.022) and LAD (HR 1.124, 95% CI 1.011-1.250, P = 0.030) were independent predictors of AF recurrence after RFCA. Our study indicated increased preprocedural GDF-15 is associated with left atrial remodeling and acts as a predictor of AF recurrence after ablation.

Morphological and functional parameters of left atrial appendage play a greater role in atrial fibrillation relapse after radiofrequency ablation

This study was to quantitatively investigate the role of morphological and functional parameters of the left atrium (LA) and left atrial appendage (LAA) with 256-slice spiral computed tomography (CT) in the recurrence of atrial fibrillation (AF) after radiofrequency ablation (RFA). Eighty-three patients with AF who underwent RFA for the first time were divided into the recurrence (n = 27) and non-recurrence (n = 56) groups. All patients underwent a 256-slice spiral CT examination before the operation. The clinical data and quantitative measurement of the morphology and functional parameters of the LA and LAA were analyzed, including the maximal and minimal volume, ejection fraction and volume, and volume strain of LAA and LA (LAAVmax, LAAVmin, LAAEF, LAAEV, and LAA-VS, LAVmax, LAVmin, LAEF, LAEV and LA-VS, respectively). The CHA2DS2-VASc score and the proportion of patients with heart failure were significantly (P < 0.05) higher in the recurrence than non-recurrence group. The LAAVmax, LAAVmin, LAVmax, LAVmin, LAAV and LAV were all significantly greater in the recurrence than non-recurrence group (P < 0.05), and the perimeter, major and minor axes of LAA orifice and LAA depth were also significantly greater in the recurrence than non-recurrence group. The LAAEF, LAEF and LAA-VS were significantly (P < 0.05) lower in the recurrence than non-recurrence group (P < 0.05). Heart failure, CHA2DS2-VASC score, LAEF, LAV, LAAEF and LAA-VS were univariately significant (P < 0.05) risk factors for AF recurrence after ablation. Multivariate analysis revealed LAAEF (HR: 0.790, 95% CI: 0.657–0.950, P = 0.012) and LAAV (HR: 1.160, 95% CI: 1.095–1.229, P <0.001) to be two significant independent predictors of recurrence. ROC curve analysis showed that LAAEF <44.68% had the highest predictive value for recurrence after radiofrequency ablation, with the sensitivity of 90% and specificity of 67.4%, whereas LAA volume >9.25 ml had the highest predictive value for AF recurrence after RFA, with the sensitivity of 85.2% and specificity of 67.9%. In conclusion, the volume of left atrium, volume and morphology of left atrial appendage have all significantly increased while the ejection fraction and volume strain of left atrium and left atrial appendage have both significantly decreased in recurrence than in non-recurrence after radiofrequency ablation. The ejection fraction and volume of left atrial appendage are significant independent predictors of atrial fibrillation recurrence after radiofrequency ablation.

A lower left atrial appendage peak emptying velocity in the acute phase of cryptogenic stroke predicts atrial fibrillation occurrence during follow-up

BACKGROUND

Silent atrial fibrillation is a frequent etiology of cryptogenic stroke. Spontaneous conversion of atrial fibrillation to sinus rhythm results in atrial stunning.

OBJECTIVE

To evaluate if the presence of a lower left atrial appendage peak emptying velocity (LAAV) after a cryptogenic stroke is associated with the occurrence of atrial fibrillation (AF).

METHODS

We retrospectively selected consecutive patients with an acute ischemic stroke that had a transoesophageal echocardiogram (TEE) performed in the first 30 days of the acute event. Documented AF or potential cardioembolic sources in the TEE were considered exclusion criteria. We assessed the LAAV. During follow-up, we evaluated the occurrence of new-onset AF and the combined endpoint of death or new ischemic stroke.

RESULTS

We studied 73 consecutive patients, during a mean follow-up period of 54.9 ± 19.3 months. Seven developed AF, and 13 had the combined endpoint. LAAV was independently associated with AF occurrence (HR: 0.93, 95% CI: 0.88-0.99; P = .016). Patients with a LAAV ≤ 46.5 cm/s (AUC: 0.766, 95% CI: 0.579-0.954; P = .021) had a lower survival rate free from AF occurrence (Log-rank, P < .001) and free from the combined endpoint of death or ischemic stroke (Log-rank, P = .010).

CONCLUSION

A lower LAAV was associated with AF occurrence and the combined endpoint of death or ischemic stroke after an initial episode of cryptogenic stroke. Patients with this finding could eventually benefit from long-term cardiac rhythm monitoring.