Are left ventricular ejection fraction and left atrial diameter related to atrial fibrillation recurrence after catheter ablation?: A meta-analysis

Pre-procedural TMAO as a predictor for recurrence of atrial fibrillation after catheter ablation

BACKGROUND

Numerous studies have demonstrated the significance of trimethylamine-N-oxide (TMAO) in the progression of atrial fibrillation (AF). However, the association between TMAO and AF recurrence (RAF) post-catheter ablation is not yet fully understood. This study aims to elucidate the predictive capability of pre-procedural TMAO levels in determining RAF following catheter ablation (CA).

METHODS

This study was conducted as a prospective, single-center observational study. Between June 2021 and June 2022, 152 patients from the Department of Cardiology at The Affiliated Huaian No. 1 People's Hospital of Nanjing Medical University were enrolled. Baseline characteristics and serum TMAO levels were assessed for all participants. Patients with AF who underwent CA were monitored for recurrences of AF using electrocardiography (ECG) or 24-hour Holter monitoring during the follow-up period.

RESULTS

The study found that serum TMAO levels were significantly higher in persistent AF (PeAF) patients compared to those in sinus rhythm (SR) and paroxysmal AF (PaAF) patients (3.96 ± 1.69 vs. 1.81 ± 0.59, 3.02 ± 1.50 µM, P < 0.001 and P < 0.01, respectively). After a one-year follow-up, 29 (21.2%) AF patients experienced recurrence after CA. Multivariate Cox proportional hazards regression analysis revealed that pre-procedural serum TMAO was an independent predictor of recurrent AF (HR = 1.78, 95% CI = 1.43-2.21, P < 0.001). The receiver operating characteristic (ROC) curve analysis identified a cut-off value of 4.3µM for serum TMAO levels in predicting recurrent AF (area under the curve: 0.835, P < 0.001). The Kaplan-Meier plot demonstrated that patients with TMAO levels greater than 4.3µM had a significantly higher rate of recurrent AF (HR = 13.53, 95% CI = 6.19-29.56, P < 0.001).

CONCLUSION

Patients with AF exhibited elevated levels of circulating TMAO compared to patients with SR. The findings suggest a potential role of TMAO in the development of AF, with pre-procedural serum TMAO levels serving as a reliable predictor of recurrence of AF CA.

The predictive value of monocyte count to high-density lipoprotein cholesterol ratio combined with left atrial diameter for post-radiofrequency ablation recurrence of paroxysmal atrial fibrillation in patients

BACKGROUND

Paroxysmal atrial fibrillation (PAF) usually recurs after radiofrequency ablation (RFA). This study probed the predictive value of monocyte count to high-density lipoprotein cholesterol (HDL-C) ratio (MHR) with left atrial diameter (LAD) for post-RFA recurrence in PFA patients.

METHODS

Totally 210 RFA-treated PAF patients were selected and assigned into Recurrence and Non-Recurrence groups, with clinical baseline data recorded. Preoperative HDL-C, hypersensitive C-reactive protein, interleukin-6, tumor necrosis factor alpha, brain natriuretic peptide, low-density lipoprotein cholesterol, total cholesterol, and total cholesterol were determined. Monocyte count and MHR were examined. The effects of preoperative MHR and LAD on post-RFA PAF recurrence was analyzed by COX regression analysis. Patients were arranged into high and low MHR and high and low LAD groups. The recurrence of PAF patients with different preoperative MHR and LAD within 12 month was analyzed by Kaplan-Meier (KM) analysis. The predictive value of preoperative MHR, LAD, and their combination for post-RFA recurrence in PAF patients was analyzed.

RESULTS

MHR and LAD were independent risk factors for post-RFA recurrence in PAF patients. KM curve shift left in the high MHR and LAD groups versus the low MHR and LAD groups. MHR and LAD could help predict post-RFA recurrence in PAF patients, and the combined predictive value of MHR and LAD was greater than that of either factor alone.

CONCLUSION

MHR and LAD are independent risk factors for post-RFA PAF recurrence, and can help predict post-RFA recurrence in PAF patients, with their combined predictive value higher than that of each factor individually.

Factors predicting the recurrence of atrial fibrillation after catheter ablation: A review

Atrial fibrillation (AF) is the most common and clinically significant type of cardiac arrhythmia. Although catheter ablation (CA) can restore sinus rhythm in patients with AF, some patients experience recurrence after the procedure. This requires us to find a simple and effective way to identify patients at a high risk of recurrence and to intervene early in the high-risk population to improve patient prognosis. The mechanism of AF recurrence is unclear, but it involves several aspects including patient history, inflammation, myocardial fibrosis, and genes. This article summarizes the current predictors of AF recurrence after CA, including myocardial fibrosis markers, inflammatory markers, MicroRNAs, Circular RNAs, AF recurrence scores, and imaging indicators. Each predictor has its own scope of application, and the predictive capacity and joint application of multiple predictors may improve the predictive power. In addition, we summarize the mechanisms involved in AF recurrence. We hope that this review will assist researchers understand the current predictors of AF recurrence and help them conduct further related studies.

Deep learning of left atrial structure and function provides link to atrial fibrillation risk

Increased left atrial volume and decreased left atrial function have long been associated with atrial fibrillation. The availability of large-scale cardiac magnetic resonance imaging data paired with genetic data provides a unique opportunity to assess the genetic contributions to left atrial structure and function, and understand their relationship with risk for atrial fibrillation. Here, we use deep learning and surface reconstruction models to measure left atrial minimum volume, maximum volume, stroke volume, and emptying fraction in 40,558 UK Biobank participants. In a genome-wide association study of 35,049 participants without pre-existing cardiovascular disease, we identify 20 common genetic loci associated with left atrial structure and function. We find that polygenic contributions to increased left atrial volume are associated with atrial fibrillation and its downstream consequences, including stroke. Through Mendelian randomization, we find evidence supporting a causal role for left atrial enlargement and dysfunction on atrial fibrillation risk.

Left Atrium Volume Measured with Multislice Computed Tomography as a Prognostic Predictor for Atrial Fibrillation Catheter Ablation Outcomes

Background: Current guidelines consider atrial fibrillation (AF) type as the prognostic factor for a recommendation of catheter ablation. We aimed to determine whether LA and LA appendage (LAA) volumes measured using multislice computed tomography (MSCT) were related to long-term outcomes in AF following radiofrequency catheter ablation (RFCA). Methods: We evaluated 152 consecutive patients with drug-refractory AF (median age, 55.8 ± 9.6 years), including 110 male patients, who underwent RFCA in a single center. All patients underwent MSCT imaging for anatomical assessment. The endpoint of this study was documented AF recurrence after RFCA. Results: The overall procedure success rate was 77.6% (n = 118) during a mean follow-up period of 12.6 months. The LA volume was significantly larger for those who experienced AF recurrence after RFCA than for the patients without recurrent AF after the procedure (153.8 ± 29.9 mL vs. 139.2 ± 34.1 mL, p = 0.025). However, LAA volumes were nearly equivalent between the patients with and without AF recurrence after RFCA (16.2 ± 6.3 mL and 14.7 ± 6.5 mL, respectively; p = 0.235). LA volume ≥ 153.2 mL was the optimal cutoff value for estimating AF recurrence after RFCA, with 94% sensitivity and 66% specificity. LA volume remained an independent predictor of both AF recurrence and permanent AF. Conclusions: LA volume as assessed by MSCT might be helpful for identifying patients likely to achieve successful AF ablation. LA volume ≥ 153.2 mL, but not LAA volume, showed good accuracy in predicting AF recurrence after RFCA.

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.

Prediction model of atrial fibrillation recurrence after Cox-Maze IV procedure in patients with chronic valvular disease and atrial fibrillation based on machine learning algorithm

OBJECTIVES

Atrial fibrillation (AF) is a prevalent cardiac arrhythmia, and Cox-maze IV procedure (CMP-IV) is a commonly employed surgical technique for its treatment. Currently, the risk factors for atrial fibrillation recurrence following CMP-IV remain relatively unclear. In recent years, machine learning algorithms have demonstrated immense potential in enhancing diagnostic accuracy, predicting patient outcomes, and devising personalized treatment strategies. This study aims to evaluate the efficacy of CMP-IV on treating chronic valvular disease with AF, utilize machine learning algorithms to identify potential risk factors for AF recurrence, construct a CMP-IV postoperative AF recurrence prediction model.

METHODS

A total of 555 patients with AF combined with chronic valvular disease, who met the criteria, were enrolled from January 2012 to December 2019 from the Second Xiangya Hospital of Central South University and the Affiliated Xinqiao Hospital of the Army Medical University, with an average age of (57.95±7.96) years, including an AF recurrence group (n=117) and an AF non-recurrence group (n=438). Kaplan-Meier method was used to analyze the sinus rhythm maintenance rate, and 9 machine learning models were developed including random forest, gradient boosting decision tree (GBDT), extreme gradient boosting (XGBoost), bootstrap aggregating, logistic regression, categorical boosting (CatBoost), support vector machine, adaptive boosting, and multi-layer perceptron. Five-fold cross-validation and model evaluation indicators [including F1 score, accuracy, precision, recall, and area under the curve (AUC)] were used to evaluate the performance of the models. The 2 best-performing models were selected for further analyze, including feature importance evaluation and Shapley additive explanations (SHAP) analysis, identifying AF recurrence risk factors, and building an AF recurrence risk prediction model.

RESULTS

The 5-year sinus rhythm maintenance rate for the patients was 82.13% (95% CI 78.51% to 85.93%). Among the 9 machine learning models, XGBoost and CatBoost models performed best, with the AUC of 0.768 (95% CI 0.742 to 0.786) and 0.762 (95% CI 0.723 to 0.801), respectively. Feature importance and SHAP analysis showed that duration of AF, preoperative left ventricular ejection fraction, postoperative heart rhythm, preoperative neutrophil-to-lymphocyte ratio, preoperative left atrial diameter, preoperative heart rate, and preoperative white blood cell were important factors for AF recurrence. Conclusion: Machine learning algorithms can be effectively used to identify potential risk factors for AF recurrence after CMP-IV. This study successfuly constructs 2 prediction model which may enhance individualized treatment plans.

Machine learning-based analysis of risk factors for atrial fibrillation recurrence after Cox-Maze IV procedure in patients with atrial fibrillation and chronic valvular disease: A retrospective cohort study with a control group

Objectives

To evaluate the efficacy of the Cox-Maze IV procedure (CMP-IV) in combination with valve surgery in patients with both atrial fibrillation (AF) and valvular disease and use machine learning algorithms to identify potential risk factors of AF recurrence.

Methods

A total of 1,026 patients with AF and valvular disease from two hospitals were included in the study. 555 patients received the CMP-IV procedure in addition to valve surgery and left atrial appendage ligation (CMP-IV group), while 471 patients only received valve surgery and left atrial appendage ligation (Non-CMP-IV group). Kaplan-Meier analysis was used to calculate the sinus rhythm maintenance rate. 58 variables were selected as variables for each group and 10 machine learning models were developed respectively. The performance of the models was evaluated using five-fold cross-validation and metrics including F1 score, accuracy, precision, and recall. The four best-performing models for each group were selected for further analysis, including feature importance evaluation and SHAP analysis.

Results

The 5-year sinus rhythm maintenance rate in the CMP-IV group was 82.13% (95% CI: 78.51%, 85.93%), while in the Non-CMP-IV group, it was 13.40% (95% CI: 10.44%, 17.20%). The eXtreme Gradient Boosting (XGBoost), LightGBM, Category Boosting (CatBoost) and Random Fores (RF) models performed the best in the CMP-IV group, with area under the curve (AUC) values of 0.768 (95% CI: 0.742, 0.786), 0.766 (95% CI: 0.744, 0.792), 0.762 (95% CI: 0.723, 0.801), and 0.732 (95% CI: 0.701, 0.763), respectively. In the Non-CMP-IV group, the LightGBM, XGBoost, CatBoost and RF models performed the best, with AUC values of 0.738 (95% CI: 0.699, 0.777), 0.732 (95% CI: 0.694, 0.770), 0.724 (95% CI: 0.668, 0.789), and 0.716 (95% CI: 0.656, 0.774), respectively. Analysis of feature importance and SHAP revealed that duration of AF, preoperative left ventricular ejection fraction, postoperative heart rhythm, preoperative neutrophil-lymphocyte ratio, preoperative left atrial diameter and heart rate were significant factors in AF recurrence.

Conclusion

CMP-IV is effective in treating AF and multiple machine learning models were successfully developed, and several risk factors were identified for AF recurrence, which may aid clinical decision-making and optimize the individual surgical management of AF.

BNP combined with echocardiographic parameters to predict the risk of cardioembolic stroke

BACKGROUND

Previous studies have found that BNP and some indicators of cardiac structure and function are closely associated with atrial fibrillation, so we aim to investigate the potential role of BNP and echocardiographic parameters to identify the acute ischemic stroke with atrial fibrillation patients who have high risks of cardioembolic stroke based on it.

METHODS

436 AIS patients were divided into an AF group and non-AF group on the basis of the electrocardiogram and Holter results. Then we compared vascular risk factors, laboratory test indicators, and echocardiographic parameters among different groups.

RESULTS

AIS with AF group had significantly higher age, CHD, previous medication, creatinine, d-dimer, fibrinogen, CRP, BNP, LAD, LVDd, LVDs and lower cholesterol, triglyceride, LDL and ejection fraction than the non-AF group (P < 0.05). Increased BNP, LAD, LVDd, LVDs and ejection fraction reduction were independent risk factors to predict cardioembolic stroke. BNP and LAD could be the two most effective indicators of the high risk of cardioembolic stroke. The area under the curve (AUC) of BNP and LAD were 0.791 [95%CI (0.743-0.838), p < 0.001), 0.786 [95%CI (0.739-0.833), p < 0.001]. The combined score we designed improved the prediction effect of single-indicator. The AUC of it was 0.822 with a sensitivity of 69.5% and specificity of 83.9%.There was an apparent positive correlation between BNP and LAD in AIS patients (r = 0.327, P < 0.001).

CONCLUSION

BNP combined with echocardiographic parameters has outstanding value to predict the risk of cardioembolic stroke, especially for BNP and LAD.

Approach to recurrence of atrial fibrillation after catheter ablation

Atrial fibrillation (AF) is the most commonly observed sustained rhythm disorder during adult ages. Since it has been shown that the ectopic beat initiating AF is usually caused by pulmonary veins, AF ablation has become the mainstay of therapy worldwide. Cryoballoon and radiofrequency ablation are the most commonly used methods in today's technologies. However, despite technological advances, the success of a single procedure in AF ablation is still limited and multiple procedures may be required for the majority of patients. In cases in which a redo ablation is required, pulmonary vein isolation is still the main target, but non-pulmonary vein targets should also be considered in AF episodes that continue despite multiple ablations. Many issues are still unclear as to which energy to choose in the first procedure, and what ablation strategy will be utilized when a redo ablation is required. The studies on this subject are very limited but, it still seems feasible and a rational approach to utilize a customized treatment strategy in each specific patient subgroup.

hsa-miR-4443 inhibits myocardial fibroblast proliferation by targeting THBS1 to regulate TGF-β1/α-SMA/collagen signaling in atrial fibrillation

Fibrosis caused by the increase in extracellular matrix in cardiac fibroblasts plays an important role in the occurrence and development of atrial fibrillation (AF). The aim of this study was to investigate the role of hsa-miR-4443 in AF, human cardiac fibroblast (HCFB) proliferation, and extracellular matrix remodeling. TaqMan Stem-loop miRNA assay was used to measure hsa-miR-4443 expression in patients with persistent AF (n=123) and healthy controls (n=100). Patients with AF were confirmed to have atrial fibrosis by late gadolinium enhancement. At the cellular level, after hsa-miR-4443 mimic and inhibitor were transfected with HCFBs, proliferation, apoptosis, migration, and invasion were analyzed. Lastly, hsa-miR-4443-targeted gene and transforming growth factor (TGF)-β1/α-SMA/collagen pathway were evaluated by dual-luciferase reporter assay and western blot, respectively. In patients with AF, hsa-miR-4443 decreased significantly and collagen metabolism level increased significantly. Logistic regression analysis showed that low hsa-miR-4443 level was a risk factor of AF (P<0.001). The receiver operating characteristic curve revealed that hsa-miR-4443 was useful for predicting AF (area under the curve: 0.828, sensitivity: 0.71, specificity: 0.78, P<0.001). In HCFBs, hsa-miR-4443 targeted thrombospondin-1 (THBS1) and downregulated TGF-β1/α-SMA/collagen pathway. The inhibition of hsa-miR-4443 expression promoted HCFB proliferation, migration, invasion, myofibroblast differentiation, and collagen production. The significant reduction of hsa-miR-4443 can be used as a biomarker for AF. hsa-miR-4443 protected AF by targeting THBS1 and regulated TGF-β1/α-SMA/collagen pathway to inhibit HCFB proliferation and collagen synthesis.

A Model Incorporating Left Ventricular Impedance Index may be Explanatory for Late Pulmonary Vein Isolation Failure

OBJECTIVE

To study the influence of a flow-based Impedance Index to attempt to explain the persistent late failure rate of Pulmonary Vein Isolation (PVI) in patients with Atrial Fibrillation (AF).

BACKGROUND

We recently described a flow-based Impedance Index for left ventricular ejection into the aorta and noted an association with Major Adverse Cardiovascular Event Rate (MACE). While the Impedance Index is not routinely measured in PVI patients it approximates to measures derivable from the left ventricular ejection fraction (EF). We sought to assess the Impedance Index's influence on PVI failure rate in combination with indices of left atrial size.

METHODS

In AF patients (n=100) undergoing a Cardiovascular Magnetic Resonance (CMR) imaging examination prior to undergoing PVI we assessed baseline characteristics for their influence on the PVI failure rate at 3-12 months. Uni-variable and multi-variable binary logistic models were performed to find predictors of the PVI failure rate at follow-up.

RESULTS

All patients underwent PVI and CMR imaging. A total of 26 (26%) patients had late AF recurrence at 3-12 months follow-up. Multi-variable models that predicted PVI failure were: 1) the baseline Impedance Index and LA volume index (p<0.05) and 2) the baseline Impedance Index and the degree of mitral valve regurgitation (MR) (p<0.001). While the Impedance Index was derived from EF, EF per se was not a predictor of PVI failure (p=0.28).

CONCLUSIONS

We have provided evidence of the influence of a flow-based Impedance Index on the PVI late failure rate which is significant and remains explanatory when adjusting for measures of atrial size, MR grade and LA volume index. Direct measure of the Impedance Index was not available here and was derived from EF measures. Further work is needed to directly measure the Impedance Index in a PVI population and determine the mechanism for the influence on PVI failure, which may lead to modification of the ablation procedure to improve the success rate.

Elevated β1-Adrenergic Receptor Autoantibody Levels Increase Atrial Fibrillation Susceptibility by Promoting Atrial Fibrosis

Objective

Beta 1-adrenergic receptor autoantibodies (β1ARAbs) have been identified as a pathogenic factor in atrial fibrillation (AF), but the underlying pathogenetic mechanism is not well understood. We assessed the hypothesis that elevated β1ARAb levels increase AF susceptibility by promoting atrial fibrosis.

Methods

A total of 70 patients with paroxysmal AF were continuously recruited. The serum levels of β1ARAb and circulating fibrosis biomarkers were analyzed by ELISA. Linear regression was used to examine the correlations of β1ARAb levels with left atrial diameter (LAD) and circulating fibrosis biomarker levels. Furthermore, we established a rabbit β1ARAb overexpression model. We conducted electrophysiological studies and multielectrode array recordings to evaluate the atrial effective refractory period (AERP), AF inducibility and electrical conduction. AF was defined as irregular, rapid atrial beats > 500 bpm for > 1000 ms. Echocardiography, hematoxylin and eosin staining, Masson's trichrome staining, and picrosirius red staining were performed to evaluate changes in atrial structure and detect fibrosis. Western blotting and PCR were used to detect alterations in the protein and mRNA expression of TGF-β1, collagen I and collagen III.

Results

Patients with a LAD ≥ 40 mm had higher β1ARAb levels than patients with a smaller LAD (8.87 ± 3.16 vs. 6.75 ± 1.34 ng/mL, P = 0.005). β1ARAb levels were positively correlated with LAD and circulating biomarker levels (all P < 0.05). Compared with the control group, the rabbits in the immune group showed the following: (1) enhanced heart rate, shortened AERP (70.00 ± 5.49 vs. 96.46 ± 3.27 ms, P < 0.001), increased AF inducibility (55% vs. 0%, P < 0.001), decreased conduction velocity and increased conduction heterogeneity; (2) enlarged LAD and elevated systolic dysfunction; (3) significant fibrosis in the left atrium identified by Masson's trichrome staining (15.17 ± 3.46 vs. 4.92 ± 1.72%, P < 0.001) and picrosirius red staining (16.76 ± 6.40 vs. 4.85 ± 0.40%, P < 0.001); and (4) increased expression levels of TGF-β1, collagen I and collagen III.

Conclusion

Our clinical and experiential studies showed that β1ARAbs participate in the development of AF and that the potential mechanism is related to the promotion of atrial fibrosis.

Efficacy and safety of cryoballoon ablation for Chinese patients over 75 years old: A comparison with a younger cohort

INTRODUCTION

Cryoballoon ablation (CBA) results in satisfactory outcomes for drug-resistant atrial fibrillation (AF) patients. However, the efficacy and safety of CBA have not yet been tested in the Chinese elderly population. Therefore, this study compared the recurrence of AF and complications of CBA in patients ≥75 years and <75 years.

METHODS

A total of 677 patients (<75 years, n = 550; ≥ 75 years, n = 127) with paroxysmal (n = 603) or persistent (n = 74) non-valvular drug-resistant AF were included. The efficacy was assessed by the recurrence of AF, and the safety was evaluated by peri- and post-procedural complications.

RESULTS

The CHA2DS2-VASc (2.6 ± 1.7 vs 4.8 ± 1.6, P < .01) and HAS-BLED (1.8 ± 0.8 vs 2.0 ± 0.8, P = .01) scores were significantly higher in the elderly group. The instant pulmonary vein isolation success rate was comparable (99.11% younger vs 98.98% older, P = .99). After a mean follow-up time of 12.8 ± 9.6 months, the 1-year freedom from AF rate was 80.6% vs 85.8% in the older and younger groups, respectively, while the survival analysis showed a nonsignificant difference in the rate of freedom from AF (log-rank P = .46). Cox regression showed that age was not a predictive factor for AF recurrence and was not dichotomized (hazard ratio [HR] = 0.868, 95% confidence interval [CI] 0.509-1.481; P = .6046) or continuous (HR = 0.990, 95% CI, 0.968-1.012, P = .3642). Similar complications rates were observed, including stroke (1.0% younger vs 0.93% older, P = .95) and major hemorrhagic events (1.2% younger vs 0% elder, P = .25).

CONCLUSIONS

The efficacy and safety profiles of CBA in patients older than 75 years are comparable with those in younger patients.

Electrophysiological and clinical characteristics of catheter ablation for isolated left side atrial tachycardia over a 10-year period

AIMS

Most left atrial tachycardia (LAT) is associated with atrial fibrillation (AF). The clinical and electrophysiological characteristics and outcomes of LAT without AF have not been investigated. This study sought to determine the long-term ablation outcomes and predictors of recurrence of isolated LAT.

METHODS

This is a single-center study of consecutive patients with isolated LAT. Atrial arrhythmia recurrence was determined from follow-up records of patients who underwent LAT ablation from 2008 to 2017. Clinical and electrophysiologic characteristics associated with atrial arrhythmia recurrence were identified.

RESULTS

A total of 50 patients (53 ± 19 years, 46% male) with 59 LAT (1.16 ± 0.47 per patient) were enrolled. Over a mean follow-up of 37 ± 33 months, atrial arrhythmia recurrence occurred in 22 (44%) patients, 11 with atrial tachycardia (AT) only, five with AF only, and six with concurrent AT and AF. The incidence of pulmonary vein (PV) origins increased significantly in the repeat procedure (P = 0.036). Multivariate analysis identified left ventricular ejection fraction (LVEF) as the only predictor of any atrial arrhythmia recurrence and LAT recurrence, while smoking and identified macroreentrant LAT in the index procedure predicted AF recurrence.

CONCLUSION

This study demonstrated a higher rate of atrial arrhythmia recurrence, including AF, among patients with initially isolated LAT. A lower LVEF predicted any atrial arrhythmia and LAT recurrence, whereas smoking and index macroreentrant AT mechanism predicted long-term AF. PV ATs were frequently observed in recurrent patients irrespective of index procedure origin.