Predictors of late recurrence of atrial fibrillation after catheter ablation

Clinical implication of the patient's disease awareness and adherence to medications in patients undergoing atrial fibrillation ablation

Background

The effects of the patient's disease awareness on the management of postablation of atrial fibrillation (AF) are unknown.

Methods

One hundred thirty-three AF patients undergoing an initial ablation were given a disease awareness questionnaire with a score of 16 points (8 points about AF in general and 8 points about oral anticoagulants) for the Jessa Atrial Fibrillation Knowledge Questionnaire (JAKQ) before and 1-year-after ablation. We divided them into the poor disease awareness group and good disease awareness group according to the median value (75%) of the total JAKQ score about AF in general, and compared the baseline patient characteristics and the 1-year changes in the JAKQ score, medication adherence, blood pressure, laboratory data, echocardiographic parameters, and AF/atrial tachycardia (AT) recurrence rate between the two groups.

Results

Forty-two (31.6%) patients were classified as having poor disease awareness (<75% of the total JAKQ score), which was closely associated with poor medication adherence, hypertension, diabetes, dyslipidemia, and greater left atrial volume (LAV). These trends in the poor disease awareness group remained unchanged 1 year after the ablation. During the 25.3-month follow-up, the AF/AT recurrence rate was significantly higher in the poor disease awareness than the good disease awareness group (23.8% vs. 7.7%; p = .003 by the log-rank test).

Conclusions

Poor disease awareness was linked to poor medication adherence, lifestyle-related diseases, and greater LAV before and even 1 year after the ablation, making it a potential surrogate marker for AF/AT recurrence. These findings highlight the clinical significance of disease awareness in AF management.

Long-term efficacy of sodium-glucose cotransporter 2 inhibitor therapy in preventing atrial fibrillation recurrence after catheter ablation in type 2 diabetes mellitus patients

Background

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) reduce new-onset atrial fibrillation (AF) in patients with type 2 diabetes mellitus (T2DM). We aimed to determine the long-term effects of SGLT2i on atrial tachyarrhythmia recurrence after catheter ablation (CA) in T2DM patients.

Methods

This retrospective study enrolled consecutive patients with T2DM undergoing CA for AF between January 2016 and December 2021. Patient baseline demographic characteristics and use of anti-diabetic and anti-arrhythmic medications were analyzed. Echocardiographic parameters were obtained one day and 6 months after CA.

Results

Our study population comprised 122 patients (70% paroxysmal AF). The baseline patient characteristics were similar between the SGLT2i-treated group (n = 45) and the non-SGLT2i-treated group (n = 77) except for stroke. At 6-month follow-up, body-mass index (BMI) was significantly decreased and left ventricular ejection fraction (LVEF) was significantly increased only in the SGLT2i group. E/e' was decreased 6 months after CA in both groups. During a mean follow-up of 33.7 ± 21.6 months, 22 of 122 patients had atrial tachyarrhythmia recurrence. The long-term atrial tachyarrhythmia-free survival rate was significantly higher in the SGLT2i-treated patients, and multivariate analysis revealed that AF type and SGLT2i use were independently associated with atrial tachyarrhythmia recurrence after CA.

Conclusion

The use of SGLT2i and AF type were independent risk factors associated with atrial tachyarrhythmia recurrence after CA in T2DM patients with AF. This result was at least partly due to the pleiotropic effects of SGLT2i on BMI reduction and left ventricular function improvement.

Effect of Prolonged Use of Dronedarone on Recurrence in Patients with Non-Paroxysmal Atrial Fibrillation After Radiofrequency Ablation (DORIS): Rationale and Design of a Randomized Multicenter, Double-Blinded Placebo-Controlled Trial

BACKGROUND

Prolonged use of anti-arrhythmic drugs (AAD) beyond the post-ablation blanking period to maintain sinus rhythm has been adopted in clinical practice but without sufficient evidence. Dronedarone is an AAD valid for maintaining sinus rhythm with fewer side effects than other AAD for long-term use.

OBJECTIVE

We sought to investigate the effect of prolonged use of dronedarone on the recurrence of non-paroxysmal AF patients beyond 3 months within the first year after ablation.

METHODS

Non-paroxysmal AF patients will receive dronedarone for 3 months after radiofrequency ablation. Patients without drug side effects and atrial tachyarrhythmia (AT) recurrence will then be randomly divided into dronedarone and placebo groups and followed up until 1 year after ablation. The primary endpoint is the cumulative nonrecurrence rate post 3 months to 1 year after ablation. Patients will receive 7-day Holter monitoring (ECG patch) at 6, 9, and 12 months after ablation to evaluate AT recurrence. Secondary endpoints include dronedarone withdrawal due to side effects or intolerance of AT recurrence, time to the first recurrence, repeat ablation, electrical cardioversion, unscheduled emergency room visit, or re-hospitalization.

CONCLUSION

This trial will evaluate whether prolonged use of dronedarone effectively reduces the recurrence rate after ablation in non-paroxysmal AF patients. The result of this trial will provide evidence for optimizing post-ablation anti-arrhythmic therapy.

TRIAL REGISTRATION

ClinicalTrials.gov ; NCT05655468, 19-December-2022.

Self-reported sleep pattern and recurrence of atrial fibrillation after catheter ablation

BACKGROUND

Increasing evidence has shown the relationship between sleep and the recurrence of atrial fibrillation (AF). However, the association of different sleep patterns with AF recurrence after catheter ablation was rarely studied. We aimed to assess the role of different sleep behaviors in the risk of AF recurrence after catheter ablation.

METHODS AND RESULTS

A total of 416 consecutive participants from Zhongda hospital of Southeast University were finally analyzed. Sleep patterns were defined by chronotype, sleep duration, insomnia, snoring, and daytime sleepiness. A total of 208 patients (50.0%) had a healthy sleep pattern within a mean follow-up of 32.42 ± 18.18 months. The observed number of patients with AF recurrence was 10 (50.0%), 80 (42.6%), and 40 (19.2%) in unhealthy, intermediate and healthy sleep groups, respectively (p < .01). After adjusting covariates, unhealthy sleep pattern was significantly associated with AF recurrence [hazard ratio = 3.47 (95% confidence interval CI: 1.726-6.979, p < .001)]. Sleep disorders such as inadequate sleep time (time <7 h or >8 h), insomnia and excessive sleepiness during daytime were associated with a higher risk of recurrence. Otherwise, improvement in sleep seemed to be associated with decreased risk of AF recurrence.

CONCLUSION

This retrospective study indicates that adherence to a healthy sleep pattern is associated with a lower risk of AF recurrence. Also, improved sleep before ablation is associated with a lower risk of AF recurrence.

Body mass index and atrial fibrillation recurrence post ablation: A systematic review and dose-response meta-analysis

Objectives

The aim of this study was to evaluate the shape of the dose-response relationship between body mass index (BMI) and atrial fibrillation (AF) recurrence in patients who have undergone radiofrequency ablation.

Methods

Studies investigating BMI and AF recurrence in patients with AF after ablation were identified through electronic searches in the PubMed, EMBASE, and Cochrane Library databases. The potential non-linear relationship was fitted using robust error meta-regression. Our study was registered with PROSPERO (CRD42019121373).

Results

Twenty-six cohort studies with 7,878 cases/26,450 individuals were included, and a linear dose-response relationship between BMI and AF recurrence (P _{non-linearity} = 0.12) was found. The risk of AF recurrence in patients with a BMI over 28 was significantly increased. Specifically, for each 5 kg/m² increase in BMI, the risk of AF recurrence increased by 15% (95% CI: 1.08-1.22) with moderate heterogeneity (I ² = 53%). Subgroup analyses showed that the pooled risk ratio was not significantly changed in subgroup analysis adjustment for the following important potential intermediate factors: left atrial diameter and obstructive sleep apnea.

Conclusion

This study showed that there is a borderline positive linear association between BMI and AF recurrence post ablation. Overweight and obesity are significantly associated with AF recurrence.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42019128770.

Mechanisms of late arrhythmia recurrence after initially successful pulmonary vein isolation in patients with atrial fibrillation

BACKGROUND

Catheter ablation is an effective treatment for atrial fibrillation (AF,) but arrhythmia recurrence occurs in a relevant number of patients. Mechanisms of late occurring arrhythmias after ablation procedures are not fully understood. We analyzed electrophysiological mechanisms of early and late arrhythmia recurrences in patients who underwent radiofrequency-based catheter ablation of AF.

METHODS AND RESULTS

Consecutive patients who underwent repeat ablation procedures after initial pulmonary vein isolation (PVI) for symptomatic arrhythmia recurrence were analyzed. A total of 110 consecutive patients who underwent catheter ablation for paroxysmal (79%) or persistent AF (21%) were included. Forty-seven patients suffered from early arrhythmia recurrence (group #1: 3-24 months), 29 patients from mid-term arrhythmia recurrences (group #2: 2-5 years), and 34 patients from late arrhythmia recurrences (group #3: > 5 years). Electrical PV reconnection was found in 98% in group #1, 72% in group #2 and 56% in group #3 (p < .001). Mode of arrhythmia recurrence was organized tachycardia in 25%, 28%, and 65% of patients in groups #1, #2, and #3 (p = .001), respectively. Patients with late arrhythmia recurrence had more pronounced left atrial low voltage as compared to patients with early arrhythmia recurrence based on two published scoring system.

CONCLUSION

Electrical PV reconnection was found in the majority of patients with early AF recurrence after PVI. In patients with late arrhythmia recurrences this mechanism may play an inferior role, with many patients presenting without PV reconnection, but with LA structural alterations. Thus, early and late occurring arrhythmia recurrence after catheter ablation may be the same symptom of different diseases.

Risk Factors of Early Atrial Fibrillation Recurrence Following Electrical Cardioversion When Left Ventricular Ejection Fraction Is Preserved

Background and objectives: To identify clinical, echocardiographic, and laboratory parameters that affect the early recurrence of atrial fibrillation (AF) after restoring sinus rhythm (SR) by electrical cardioversion (ECV), and to determine whether left atrial (LA) strain, as a noninvasive indicator reflecting fibrosis, is associated with laboratory indicators affecting the development of fibrosis, interleukin 6 (IL-6) or tumor necrosis factor α (TNF-α). Materials and Methods: The study included 92 persistent AF patients who underwent elective ECV. The effective maintenance of SR was evaluated after 40 ± 10 days of ECV. Echocardiography, inflammatory markers (high-sensitivity c-reactive protein (hs-CRP), IL-6, and TNF-α), and natriuretic peptides (N-terminal pro b-type natriuretic peptide (NT-proBNP) and N-terminal pro a-type natriuretic peptide (NT-proANP)) were assessed. Results: After a 40 ± 10 days observation period, 51 patients (55.4%) were in SR. Patients with AF recurrence had a significantly longer duration of AF (p = 0.008) and of arterial hypertension (p = 0.035), lower LA ejection fraction (p = 0.009), lower LA strain (p < 0.0001), higher left ventricular global longitudinal strain (p = 0.001), and a higher E/e‘ ratio (p < 0.0001). LA strain was an independent predictor of early AF recurrence (OR: 0.65; 95% Cl 0.5−0.9, p = 0.004). LA strain < 11.85% predicted AF recurrence with 70% sensitivity and 88% specificity (AUC 0.855, 95% CI 0.77−0.94, p < 0.0001). LA strain demonstrated the association with NT-proBNP (r = −0.489, p < 0.0001) and NT-proANP (r = −0.378, p = 0.002), as well as with hs-CRP (r = −0.243, p = 0.04). Conclusions: LA strain appeared to be the most accurate predictor of early AF recurrence after ECV in patients with persistent AF. LA strain inversely correlated with NT-proBNP and NT-proANP, but no significant association with any of the inflammatory markers was identified.

Late arrhythmia recurrence after atrial fibrillation ablation: incidence, mechanisms and clinical implications

Background and objectives

Catheter ablation of atrial fibrillation (AF) has become a well-established and widely used therapy, with pulmonary vein isolation (PVI) being the key modality of ablation. However, arrhythmia recurrences after PVI are common, with a relevant number of patients undergoing repeat ablation. Arrhythmia recurrence after PVI may vary regarding time point and mode of recurrence. While early arrhythmia recurrences of AF after PVI are mostly found to be the product of electrical reconnection of the pulmonary veins, the exact mechanisms of very late arrhythmia recurrence, occurring later than 12 months after successful PVI, remain unclear. This review provides an overview on the current evidence on time point and mechanisms of arrhythmia recurrence after PVI focussing on late arrhythmia recurrence.

Recent findings

The incidence of late arrhythmia recurrence after PVI can lie at a rate of up to 30% according to long-term follow-up studies. Mechanisms of recurrence include electrical reconnection of previously isolated pulmonary veins and development of atrial fibrosis. The use of cryoballoon ablation is likely to be more effective in reducing late arrhythmia recurrences compared to radiofrequency ablation. Novel scores such as the MB-LATER score or the APPLE score may become useful tools in predicting arrhythmia recurrence after PVI.

Results and conclusion

Late arrhythmia recurrence after PVI is common and leads to a relevant impairment of long-term success. Relevant data are currently limited and exact mechanisms of arrhythmia recurrence remain unclear. Further studies are needed to elucidate pathogenetic mechanisms of late arrhythmia recurrence after PVI in order to improve treatment strategies.

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.

Short coupling interval with high burden of atrial ectopy predicts recurrence after atrial fibrillation ablation

Atrial ectopy (AE) with a short coupling interval (S-AE) causes atrial fibrillation (AF). A higher burden of AE is associated with recurrence after AF ablation. However, a few reports have evaluated the prognostic impact of both AE burden and S-AE after the acute phase of ablation. This study aimed to assess the characteristics of AE beyond the blanking period in predicting the recurrence. We retrospectively analyzed 173 patients who underwent first catheter ablation for AF and 24-h Holter recording following a 3-month blanking period. AE was defined as a narrow QRS complex occurring < 75% earlier than the prior reference R-R interval. We investigated the relationship between the AE's characteristics in Holter recordings and atrial arrhythmia recurrence. Forty-two patients (24%) had a recurrence during a median 488-day follow-up. Patients with S-AE (minimum coupling interval ratio of AE ≤ 45%) had a higher recurrence rate than those without S-AE (44.9% vs. 16.1%, p < 0.001). Moreover, patients with AE ≥ 241/day exhibited a significantly higher recurrence rate than those with AE < 241/day (44.3% vs. 10.7%, p < 0.001). In multivariate analysis, S-AE with a higher AE burden was an independent predictor of recurrence (hazard ratio 5.82, 95% confidence interval: 2.64-12.82, p < 0.001). Kaplan-Meier analysis showed that patients with S-AE and a higher AE burden had the worst prognosis for recurrence (p < 0.001). The combination of a higher AE burden with S-AE could be an efficient predictor of recurrence. These results can help to develop follow-up strategies after AF ablation.

Impact of Midregional N-Terminal Pro-Atrial Natriuretic Peptide and Soluble Suppression of Tumorigenicity 2 Levels on Heart Rhythm in Patients Treated With Catheter Ablation for Atrial Fibrillation: The Biorhythm Study

Background

We assessed the impact of preprocedural plasma levels of MRproANP (midregional N‐terminal pro–atrial natriuretic peptide) and sST2 (soluble suppression of tumorigenicity 2) on recurrence of atrial fibrillation (AF) at 1 year after catheter ablation of AF.

Methods and Results

This was a prospective, multicenter, observational study including patients undergoing catheter ablation of AF. MRproANP and sST2 were measured in a peripheral venous blood preprocedure, and MRproANP was assessed in the right and left atrial blood during ablation. The primary end point was recurrent AF between 3 and 12 months postablation, defined as a documented (>30 seconds) episode of AF, flutter, or atrial tachycardia. We included 106 patients from December 2017 to March 2019; 105 had complete follow‐up, and the mean age was 63 years with 74.2% males. Overall, 34 patients (32.1%) had recurrent AF. In peripheral venous blood, MRproANP was significantly higher in patients with recurrent AF (median, 192.2; [quartile 1–quartile 3, 155.9–263.9] versus 97.1 [60.9–150.7] pmol/L; P<0.0001), as was sST2 (median, 30.3 [quartile 1–quartile 3, 23.3–39.3] versus 23.4 [95% CI, 17.4–33.0] ng/mL; P=0.0033). In the atria, MRproANP was significantly higher than in peripheral blood and was higher during AF than during sinus rhythm. Receiver operating characteristic curve analysis identified a threshold of MRproANP>107.9 pmol/L to predict AF recurrence at 1 year and a threshold of >26.7 ng/mL for sST2. By multivariate analysis, MRproANP>107.9 pmol/L was the only independent predictor of recurrent AF (OR, 24.27; 95% CI, 4.23–139.18). MRproANP<107.9 pmol/L identified subjects at very low risk of recurrence (negative predictive value >95%).

Conclusions

Elevated MRproANP level independently predicts recurrent AF, whereas sST2 levels do not appear to have any prognostic value in assessing the risk of recurrence of AF up to 1 year after catheter ablation.

Registration

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03351816.

Prediction of arrhythmia recurrence after atrial fibrillation ablation in patients with normal anatomy of the left atrium

BACKGROUND

Enlarged left atrium is an established predictor of atrial fibrillation recurrence after pulmonary vein isolation but arrhythmia recurrence is also observed in patients with normal anatomy of the left atrium. The aim of the study is to evaluate arrhythmia recurrence predictors in patients with normal anatomy of the left atrium.

METHODS

The study included 182 patients with normal anatomy of the left atrium who underwent pulmonary vein isolation using catheter ablation. Various parameters were also compared, including age, gender, history of arrhythmia, arterial hypertension, concomitant coronary pathology, echocardiography findings, such as mitral valve and tricuspid valve regurgitation and procedure parameters, between patients with and without relapses. Statistical analysis was performed using the IBM SPSS Statistics-19 software.

RESULTS

Transthoracic echocardiography was performed by independent specialists with extensive experience. Trans-esophageal echocardiography was performed before each ablation procedure. Standard trans-septal puncture was performed under fluoroscopic control. Radiofrequency ablation was performed in the ipsilateral pulmonary vein antrum with a wide capture of nearby lung tissue.

CONCLUSIONS

It was concluded that the tricuspid valve regurgitation and arterial hypertension correlate with atrial fibrillation recurrence after pulmonary vein isolation in patients with normal left atrial anatomy.

[Success rate of one-stop procedure for atrial fibrillation ablation and its impact on cardiac function: a propensity-matched study]

OBJECTIVE

To investigate the effect of the combination of atrial fibrillation (AF) ablation and left atrial appendage closure (LAAC) on cardiac function and the success rate of AF ablation.

METHODS

We retrospectively analyzed the data of 56 patients with AF undergoing a one-stop procedure for AF ablation and LAAC in our hospital between May, 2015 and May, 2019. Propensity score matching (PSM) at the ratio of 1:1 was used to select 56 control patients undergoing AF ablation at high risk of stroke, for matching with the hybrid procedure group. The perioperative complications, thromboembolic events, recurrence of atrial arrhythmia and cardiac function were compared between the groups.

RESULTS

The two groups of patients were comparable for age, gender, BMI, duration and type of AF, concomitant diseases, CHA2DS2-VASc and HAS-BLED scores (P > 0.05). The incidence of complications did not differ significantly between the hybrid procedure group and AF ablation group (17.9% vs 12.5%, P=0.430). Compared with the control patients with AF ablation alone, the patients undergoing the hybrid procedure had a lowered incidence of thromboembolic events, but the difference was not statistically significant (1.8%vs 3.6%, P=1.000). The hybrid procedure did not improve the success rate of AF ablation (OR: 1.338, 95%CI: 0.451-3.973, P= 0.600) but significantly improved the cardiac function parameters including NT-pro BNP (945.3±1401.6 pg/mL vs 1520.7±2089.1 pg/mL, P=0.010), LVEF[(60.8±7.0)% vs (58.6±7.8)%, P=0.044], and left atrial diameter (43.9±7.5 mm vs 45.6±6.3 mm, P=0.076); but the improvement of cardiac function was more obvious in the control patients undergoing AF ablation alone (P < 0.039).

CONCLUSIONS

The combination of AF ablation and LAAC is safe but does not improve the success rate of AF ablation. The one-stop procedure can improve cardiac function of the patients, but AF ablation alone can achieve better improvement of cardiac function.

Frequency of postoperative atrial fibrillation and related parameters in patients who underwent sleeve gastrectomy for obesity

BACKGROUND

In this study, we planned to determine the frequency of postoperative AF and its related parameters in morbidly obese patients who underwent bariatric surgery.

METHODS

The study included 300 patients with morbidly obese who had no history of AF and underwent successful bariatric surgery. Routine anamnesis, physical examination and laboratory parameters of the patients were recorded. Patients with postoperative AF were detected. The participants were grouped as patients with and without AF.

RESULTS

Postoperative AF occurred in 19 (6.3%) patients. Age, BMI and LAd diameter parameters independently determined the presence of AF. When the ROC curve was performed to identify patients with AF, the area under the ROC curve was found to be 0.841, 0.785 and 0.902 for age, BMI and LAd diameter, respectively. According to this analysis, 50 years for age, 43 kg/m² for BMI and 40 mm for LAd were used to determine patients with AF with acceptable sensitivity and specificity (>70% each).

CONCLUSIONS

The most important determinants of postoperative AF are age, LAd and basal BMI. Therefore, morbidly obese patients with LAd >40 mm, BMI >43 kg/m² and >50 years of age should be followed up more closely for postoperative AF development and preoperative precautions should be taken to prevent AF development.

Epicardial Fat Volume as a New Imaging-Based Feature Associated with Risk of Recurrence after Pulmonary Veins Ablation in Atrial Fibrillation

Background: Atrial fibrillation (AF), a common arrhythmia in clinical practice, is associated with a high rate of complications and an increased risk for thromboembolic events. Pulmonary vein ablation is a new therapeutic option to cure AF; however, it remains associated with a high rate of recurrence. In this study we aimed to identify the clinical characteristics and imaging-based features that may predict the risk of recurrence after pulmonary veins ablation in atrial fibrillation.

Materials and method: Twenty-four patients with paroxysmal and persistent AF, who underwent radiofrequency catheter ablation and a 12-month follow-up were included in the study. Group 1 included 8 patients with AF recurrence, and group 2 included 16 patients with no AF recurrence. In all cases, cardiovascular risk factors, ejection fraction, left atrial diameter, atrial volumes, and epicardial fat volume were analyzed.

Results: CT analysis revealed that patients with AF recurrence presented a significantly larger mean index of left atrial volume (59.57 ± 8.52 mL/m2 vs. 49.99 ± 10.88 mL/m2, p = 0.04), right atrial volume (58.94 ± 8.37 mL/m2 vs. 43.21 ± 6.4 mL/m2, p<0.0001), and indexed bi-atrial volume (118.5 ± 15.82 mL/m2 vs. 93.19 ± 16.42 mL/m2, p = 0.005). At the same time, CT analysis of the epicardial adipose tissue volume indicated that patients with AF recurrence have a larger amount of epicardial fat than those without AF recurrence (176.4 ± 100.8 mL vs. 109.8 ± 40.73 mL, p = 0.02).

Conclusion: Left atrial diameter, indexed atrial volumes, and epicardial fat volume may be used as factors to identify patients at risk for developing recurrence after pulmonary vein ablation.

Long-term results of monopolar versus bipolar radiofrequency ablation procedure for atrial fibrillation

Background

In this study, we aimed to evaluate the long-term outcomes of monopolar or bipolar radiofrequency ablation concomitant to mitral valve surgery in patients with atrial fibrillation.

Methods

We retrospectively evaluated a total of 167 patients (67 males, 100 females; mean age 56.8±6.9 years; range, 48 to 65 years) with atrial fibrillation who underwent monopolar or bipolar radiofrequency ablation concomitant to mitral valve surgery between September 2001 and January 2015. The patients were divided into two groups according to the procedure applied as those undergoing monopolar ablation (group 1, n=68) and those undergoing bipolar ablation (group 2, n=99). All patients were followed by electrocardiogram and 24-h Holter monitoring. Echocardiography was performed before discharge, at three and 12 months postoperatively, and annually thereafter. Left atrial volume index, left atrial diameter, and left ventricular ejection fraction were recorded.

Results

There was no significant correlation between the procedure applied and hypertension, hyperlipidemia, diabetes mellitus, chronic obstructive pulmonary disease, history of the cerebrovascular events (p>0.05). The mean preoperative left atrial diameter decreased from 5.3±0.5 cm to 4.9±0.5 cm postoperatively in all patients (p=0.0001). The mean preoperative left atrial volume index decreased from 53.8±0.4 mL/m2 t o 43.7±6.2 m L/m2 i n t he postoperative period (p=0.0001). During follow-up, 61.8% (n=42) of the patients in group 1 and 62.6% (n=62) of the patients in group 2 remained in sinus rhythm. One patient (1.5%) in group 1 and two patients (2.0%) in group 2 developed early postoperative cerebrovascular accident.

Conclusion

Monopolar and bipolar ablation methods are safe and effective methods to ensure long-term sinus rhythm. Both procedures do not increase the morbidity risk with very low thromboembolic complication rates.

Predictors of Recurrence of AF in Patients After Radiofrequency Ablation

Catheter ablation is a well-known treatment for patients with AF. Despite the growing knowledge in the field, the identification of predictors of recurrence of AF after catheter ablation is one of the primary goals and is of major importance to improve long-term results of the procedure. The aim of this article is to provide an overview of what has been published in recent years and to summarise the major predictors, helping cardiac electrophysiologists in the selection of the right candidates for catheter ablation.

Genetics of Atrial Fibrillation

Background

Atrial fibrillation (AF) is a common arrhythmia seen in clinical practice. Occasionally, no common risk factors are present in patients with this arrhythmia. This suggests the potential underlying role of genetic factors associated with predisposition to developing AF.

Methods and Results

We conducted a comprehensive review of the literature through large online libraries, including PubMed. Many different potassium and sodium channel mutations have been discussed in their relation to AF. There have also been non–ion channel mutations that have been linked to AF. Genome‐wide association studies have helped in identifying potential links between single‐nucleotide polymorphisms and AF. Ancestry studies have also highlighted a role of genetics in AF. Blacks with a higher percentage of European ancestry are at higher risk of developing AF. The emerging field of ablatogenomics involves the use of genetic profiles in their relation to recurrence of AF after catheter ablation.

Conclusions

The evidence for the underlying role of genetics in AF continues to expand. Ultimately, the role of genetics in risk stratification of AF and its recurrence is of significant interest. No established risk scores that are useful in clinical practice are present to date.

Impact of Body Mass Index on the Outcomes of Catheter Ablation of Atrial Fibrillation: A European Observational Multicenter Study

Background Outcomes of catheter ablation of atrial fibrillation (AF) are variable and the predictors of success require further elucidation since the identification of correctable risk factors could help to optimize therapy. We aimed to assess the impact of body mass index (BMI) in the overall safety and efficacy of catheter ablation of AF, with emphasis on the use of cryoballoon ablation and novel oral anticoagulants. Methods and Results There were 2497 consecutive patients undergoing catheter ablation of AF in 7 European high volume centers were stratified according to BMI (normal weight <25 kg/m2, pre-obese 25-30 kg/m2, obesity 30-35 kg/m2, and morbid obesity ≥35 kg/m2) and comparisons of procedural outcomes evaluated. Pre-obese and obese patients presented more comorbidities (hypertension, diabetes mellitus, and sleep apnea), and had higher rates of non-paroxysmal AF ablation procedures. The rate of atrial 12-month arrhythmia relapse increased alongside with BMI (35.2%, 35.7%, 43.6%, and 48.0% P<0.001). During a median follow-up of 18.8 months (interquartile range 11-28), after adjusting for all baseline differences, BMI was an independent predictor of relapse (hazard ratio=1.01 per kg/m2; 95% CI 1.01-1.02; P=0.002), adding incremental predictive value to obstructive sleep apnea. BMI was not a predictor for any of the reported complications. Using novel oral anticoagulants and cryoballoon ablation was safe and efficacy was comparable with vitamin-K antagonists and radiofrequency ablation. Conclusions Obese patients present with a more adverse comorbidity profile, more advanced forms of AF, and have lower chances of being free from AF relapse after ablation. Use of novel oral anticoagulants and cryoballoon ablation may be an option in this patient group.

Association Between Pre-Ablation Glycemic Control and Outcomes Among Patients With Diabetes Undergoing Atrial Fibrillation Ablation

OBJECTIVES

The aim of this study was to investigate the impact of improved glycemic control on atrial fibrillation (AF) recurrence rates after ablation.

BACKGROUND

Diabetes is associated with increased rates of AF. The impact of improved pre-ablation glycemic control remains unknown.

METHODS

The 12-month pre-ablation trends in glycemic control were studied in 298 patients with diabetes undergoing AF ablation. Recurrence data were obtained during a mean follow-up period of 25.92 ± 20.26 months post-ablation.

RESULTS

Higher glycated hemoglobin (HbA_1c) at the time of ablation was associated with higher post-ablation recurrence rates. More than two-thirds (68.75%) of patients with HbA_1c >9% at the time of ablation developed recurrent AF, compared with 32.4% of those with HbA_1c <7% (p < 0.0001). On multivariate analysis, only the 12-month trend in HbA_1c was significantly associated with AF recurrence. Although 91.1% of patients with a worsening trend in HbA_1c during the 12 months prior to ablation developed recurrent AF, only 2% of patients with improvements in HbA_1c of 10% or more experienced AF recurrence (p < 0.0001).

CONCLUSIONS

The trend in glycemic control prior to ablation predicts arrhythmia recurrence after ablation. A multidisciplinary approach to reduce HbA_1c is imperative in patients with diabetes with AF to reduce recurrence rates after ablation.

Association between gene variants and the recurrence of atrial fibrillation: An updated meta-analysis

BACKGROUND

Studies showed the controversial results about the effect of common genetic polymorphisms on the atrial fibrillation (AF) recurrence. We performed the systematic review and meta-analysis to qualify the association between common genetic polymorphisms and AF recurrence.

METHODS

Articles were systematically retrieved PubMed, Web of Science, EMBASE, Wanfang, and CNKI database and 9 studies including 3204 patients were enrolled in our meta-analysis.

RESULTS

Results showed that the associations were significant under rs2200733 3 genetic models (TT vs CC: odds ratio [OR] [confidence interval [CI]] = 1.336 [1.061-1.683], P = .014; CT vs CC: OR [CI] = 0.759 [0.614-0.937], P = .01; TT vs CT + CC: OR [CI] = 2.308 [1.440-3.700], P = .001). The association was significant under rs10033464 genetic model (TT vs GG: OR [CI] = 1.517 [1.165-1.976], P = .002).

CONCLUSIONS

Rs13376333 on chromosome 1q21 (in KCNN3), rs7193343 and rs2106261 on chromosome 16q22 (in ZFHX3) were not associated with AF recurrence in our meta-analysis. In total, our meta-analysis found that rs2200733 and rs10033464 on chromosome 4q25 (near PITX2) were associated with the risk of AF recurrence.

Serum relaxin level predicts recurrence of atrial fibrillation after radiofrequency catheter ablation

Relaxin, an emerging biomarker in heart failure, is involved in fibrosis and inflammation. The value of relaxin in predicting recurrence of atrial fibrillation (AF) after radiofrequency catheter ablation (RFCA) is unknown and the subject of this study. We prospectively enrolled 248 consecutive patients with AF (paroxysmal in 127 and persistent in 121) who underwent RFCA at our center after measurement of circulating levels of relaxin by ELISA. Kaplan-Meier analysis with log-rank test and multivariate analysis were used to assess the association between pre-RFCA relaxin levels and post-RFCA AF recurrence at 18 months follow-up. At mean 16.3 ± 3.8 months post-RFCA, 195 (78.6%) patients maintained sinus rhythm, and their pre-RFCA relaxin level was lower than that in patients with AF recurrence (P < 0.001). From lowest to highest pre-RFCA relaxin level tertiles (T1; 82.10-< 234.36; T2; 234.36-< 342.26; and T3; 342.26-740.63 ng/L), AF recurrence rate increased significantly (8.5%, 20.5% and 34.9%, respectively; Kaplan-Meier analysis with log-rank test, χ² = 18.44, P < 0.001). Using a cutoff of 285.4 ng/L, pre-RFCA relaxin level predicted AF recurrence during follow-up with sensitivity of 77.4% and specificity of 55.9% (area under the receiver operating characteristic curve = 0.71). On multivariate Cox proportional hazard model, relaxin level by tertile (T2, hazard ratio 2.678; 95% confidence interval 1.110-6.460; P = 0.028, and T3, hazard ratio 4.745; 95% confidence interval 2.075-10.854; P < 0.001, respectively compared with the T1) was the independent factor predicting recurrence. Elevated pre-RFCA relaxin level is associated with post-RFCA AF recurrence. A simple measurement of relaxin level therefore might help identify patients at high risk of AF recurrence after RFCA.Clinical Trial Registration chictr.org.cn identifier: ChiCTR-OOC-15006130.

Prediction and Management of Recurrences after Catheter Ablation in Atrial Fibrillation and Heart Failure

Catheter ablation is recommended in patients with symptomatic atrial fibrillation (AF) refractory to pharmacologic therapy. AF recurrence is common postablation, particularly in patients with heart failure, because of multiple structural and functional changes that can occur. Determining predictors of AF recurrence has become increasingly important. These include increased left atrial volume, termination of AF during the index ablation, electrocardiogram parameters, and serum biomarkers. Cardiac MRI can also determine the degree of scarring and left atrial sphericity, which is used in risk prediction scores. In patients with recurrence, further treatment options include pharmacologic therapy and atrioventricular nodal ablation with pacing.

Radiofrequency catheter ablation for paroxysmal atrial fibrillation: outcomes during a 3-year follow-up period

Objective

This study was performed to observe the effect of radiofrequency catheter ablation (RFCA) in patients with paroxysmal atrial fibrillation (PAF) and to explore the risk factors for late recurrence of atrial fibrillation (LRAF) after a single RFCA session.

Methods

In this retrospective study, 243 patients with PAF underwent RFCA and were followed up regularly.

Results

At a median follow-up of 37 months after a single procedure, 60.5% of patients maintained sinus rhythm (SR), and at a median follow-up of 42 months after multiple procedures, 74.9% of patients maintained SR. The statistically significant risk factors for LRAF after a single RFCA session were the left atrial diameter (LAD), left inferior pulmonary vein superior–inferior diameter (LIPV SID), PV number variation, circumferential pulmonary vein isolation (CPVI) combined with additional ablation, and early recurrence of atrial fibrillation (ERAF). The best cut-off value for LAD was 35.5 mm.

Conclusions

During a 3-year follow-up, about 70% of the patients with PAF maintained SR. LRAF after a single procedure was associated with the LAD, LIPV SID, PV number variation, CPVI combined with additional ablation, and ERAF.

Predictors of Short and Long Term Recurrences of Paroxysmal AF after Radiofrequency Ablation. Is Blanking Period Really Benign?

Background

Following pulmonary vein isolation for paroxysmal atrial fibrillation (PAF), early recurrences of atrial arrhythmias (ERAA) are frequent, classified benign as a part of a blanking period. But recently it seems that there is increased incidence of late recurrences in patients with ERAA but mechanism is still unknown.

Purpose

To assess the incidence and risk factors for early and late AF recurrences post AF ablation and the impact of these ERAA on long-term success.

Methods

Thirty-six consecutive patients (age 45 ± 11 years, 72% males) undergoing RF ablation for PAF. They were followed up in hospital for 2 days post ablation then every week for one month. Subsequent follow-up visits consisted of clinical interview, ECGs, and 24h Holter monitoring every 3 months were done for one year. Extended Holter monitoring was done for patients with palpitations. Any episode of symptomatic or asymptomatic documented atrial tachyarrhythmia > 30 seconds was considered recurrence.

Results

Prevalence of ERAA during first 3 months was 47.2%, while late AF recurrence was 25%. 35% of patients with ERAA had late AF recurrence. ≥ 2 attacks of ERAA during the blanking period had significant diagnostic performance in prediction of late AF with sensitivity 44% and specificity 100% (p value=0.05) and also long procedural time ( with sensitivity 89% and specificity 63% (p value=0.049). Multivariate logistic regression showed that frequent ERAA attacks was the only significant factor that increases the risk of late AF recurrence (p value =0.008, OR= 4.39, 95% CI=1.48-12.99).

Conclusion

ERAA in blanking period may be associated with increased risk for late AF recurrence. Frequent episodes of early recurrences (≥ 2 attacks) is a strong predictor for late AF recurrence. These data should be considered during follow up of the patients with paroxysmal AF after ablation.

Effect of epicardial fat and metabolic syndrome on reverse atrial remodeling after ablation for atrial fibrillation

BACKGROUND

Metabolic syndrome/epicardial adipose tissue (EAT) plays an important role in atrial fibrillation (AF). Although reverse atrial remodeling (RAR) often occurs after AF ablation, the effects of EAT on RAR remain unknown.

METHODS

Study subjects were 104 patients in whom transthoracic echocardiography (TTE) was performed before AF ablation and 3, 6, and 12 months afterward. EAT was assessed in terms of its thickness adjacent to the right ventricular anterior wall in the TTE parasternal view. RAR was defined as >10% reduction in the left atrial volume (LAV) index by the 3-month follow-up examination.

RESULTS

Postablation RAR occurred in 57/104 (55%) patients. RAR absence was associated with a relatively thick EAT (4.92 ± 1.65 vs. 3.92 ± 1.17 mm, P = 0.0005), small LAV index (24.6 ± 7.5 vs. 28.8 ± 10.6 mL/m2, P = 0.0233), and metabolic syndrome (62% vs. 28%, P = 0.0006). Metabolic syndrome and EAT were shown to be independent predictors of RAR absence. Thick EAT was significantly associated with AF recurrence after ablation (5.05 ± 2.19 mm vs. 4.17 ± 1.16 mm for no AF recurrence group, P = 0.0116), but metabolic syndrome was not (48% vs. 42%, P = 0.6189). Despite no change in body weight, EAT thickness decreased significantly by 12 months in patients without AF recurrence (4.17 ± 1.16 vs. 3.65 ± 1.16 mm, P < 0.0001).

CONCLUSIONS

EAT and metabolic syndrome appear to be strongly associated with RAR absence, but only the thick EAT was significantly associated with the postablation AF recurrence. Our findings, especially the thinning of EAT, suggest that thick EAT lead to AF vulnerability but that EAT reduction favorably affects ablation outcome.

Clinical significance of the timing of early recurrence of atrial arrhythmia after pulmonary vein isolation: a two-institution clinical study

Early recurrence of atrial arrhythmia (ERAA) after ablation frequently occurs, but there is limited evidence about ERAA-timing. This study aimed to investigate the association between ERAA-timing and late recurrence. We retrospectively investigated 332 patients who underwent PVI for paroxysmal atrial fibrillation at Nagoya University Hospital and Komaki City Hospital. Seventy-six patients (23%) had ERAA. The cutoff value of the first ERAA for late recurrence was set as 3 days, with a specificity of 77% and sensitivity of 43%. On multivariate analysis, first ERAA beyond 3 days (hazard ratio, 2.477; 95% confidence interval, 1.168-5.25; p = 0.018) and large left atrial diameter (LAD) (hazard ratio, 1.101; 95% confidence interval, 1.024-1.184; p = 0.009) were independent predictors for late recurrence. Patients who had first ERAA within 3 days and no ERAA beyond 3 days showed a significantly higher recurrence-free rate than those who had first ERAA beyond 3 days and those who had ERAA both within 3 days and beyond 3 days (89% versus 39%, 44%; p  < 0.001). Moreover, the patients with ERAA within 3 days and LAD ≤ 37.7 mm showed a significantly higher recurrence-free rate than those with ERAA beyond 3 days and LAD > 37.7 mm, and as compared with the other patients (100% versus 26% and 60%, respectively; p < 0.001). ERAA beyond 3 days after ablation was a predictor for late recurrence. Among patients with ERAA, those with ERAA within 3 days and smaller LAD showed favorable prognosis after ablation.

Apelin: A novel prognostic predictor for atrial fibrillation recurrence after pulmonary vein isolation

Apelin, the ligand for the APJ receptor, is involved in the pathogenesis of atrial fibrillation (AF). However, whether serum apelin can predict the recurrence of AF after pulmonary vein isolation (PVI) has not been determined.A prospective cohort study was performed in patients with AF (but without structural heart disease) who were undergoing first-time PVI. Serum apelin-12 was measured by enzyme-linked immunosorbent assay. Echocardiographic examination was performed at baseline, 3 months, and 6 months after PVI. Patients were followed up for 6 months after PVI, and the association between baseline apelin-12 and AF recurrence (early recurrence: within 3 months after ablation; late recurrence: 3-6 months after ablation) was analyzed.A total of 61 patients were included in the study. Baseline serum level of apelin-12 was significant lower in patients with early (median [interquartile range]: 1844 [1607-2061] vs 2197 [1895-2455] ng/L, P = .01) and late (1639 [1524-1853] vs 1923 [1741-2303] ng/L, P = .02) AF recurrence compared with patients without these events. Results of Cox stepwise multivariate analysis demonstrated that lower baseline apelin-12 (<2265 ng/L) was independently associated with increased AF recurrence within 6 months after PVI (P < .05). The specificity and positive predictive value of apelin-12 for AF recurrence were significantly higher than those of baseline N-terminal brain proBNP (60.4% vs 28.6%, P < .001; 58.8% vs 34.4%, P = .01), although the sensitivity and negative predictive value were similar.Reduced baseline serum apelin-12 may be an independent risk factor for the recurrence of AF after PVI in patients without structural heart disease.

Predictors of atrial fibrillation early recurrence following cryoballoon ablation of pulmonary veins using statistical assessment and machine learning algorithms

Inflammation, oxidative stress, myocardial injury biomarkers and clinical parameters (longer AF duration, left atrial enlargement, the metabolic syndrome) are factors commonly related to AF recurrence. This study aims to assess the predictive value of laboratory and clinical parameters responsible for early recurrence of atrial fibrillation (ERAF) following cryoballoon ablation (CBA) using statistical assessment and machine learning algorithms. This study group comprised 118 consecutive patients (mean age, 62.5 ± 7.8 years; women 36%) with paroxysmal (54.1%) and persistent (45.9%) AF who underwent their first pulmonary vein isolation (PVI) performed by CBA (Arctic Front Advance 2nd generation 28 mm). The biomarker concentrations were measured at baseline and after CBA in a 24-h follow-up. ERAF was defined as at least a 30-s episode of arrhythmia registered by a 24 h-Holter monitor within the 3 months following the procedure. 56 clinical, laboratory and procedural variables were collected from each patient. We used two classification algorithms: support vector machines, gradient boosted tree. The synthetic minority over-sampling technique (SMOTE) was used to provide a balanced training data set. Within a period of 3 months 21 patients (17.8%) experienced ERAF. The statistical analysis indicated that the lowered levels of post-ablation TnT (p = 0.043) and CK-MB (p = 0.010) with the TnT elevation (p = 0.044) were the predictors of ERAF following CBA. In addition, diabetes and statin treatment were significantly associated with ERAF after CBA (p < 0.05). The machine learning algorithms confirmed the results obtained in the univariate analysis.

Long-term outcome of radiofrequency catheter ablation for persistent atrial fibrillation

Catheter ablation has been wildly used to treat atrial fibrillation (AF) and has achieved a better efficacy for paroxysmal AF (PAF) but not for persistent AF (PerAF). Furthermore, a few data on the efficacy and safety of catheter ablation for PerAF were reported. This study aimed to investigate long-term efficacy of radiofrequency catheter ablation (RFCA) for PerAF and explore predictors of late recurrence of atrial fibrillation (LRAF).A total of 92 consecutive patients with PerAF (64 males, aged 56.42 ± 11.24 years) were enrolled in this study and accepted circumferential pulmonary vein isolation (CPVI) alone or CPVI combined additional ablation.Maintenance rate of sinus rhythm (SR) was 40.2% after a single procedure with median follow-up of 15 months and 52.2% after mean 1.3 ± 0.6 procedures with median follow-up of 26 months. Long-term SR maintenance rate was no statistical difference between patients with CPVI alone and with CPVI combined additional ablation (48.6% vs 35.1%, log rank test, P = .152). Patients with AF duration < 24 months had a higher long-term SR maintenance rate than those with AF duration ≥ 24 months (55.6% vs 30.4%, log rank test, P = .022). AF duration (OR = 1.015, 95%CI 1.001-1.030, P = .015), and early recurrence of AF (ERAF) (OR = 10.654, 95%CI 3.853-29.460, P < .001) were predictors of LRAF after a single procedure.In conclusion, long-term maintenance SR rate was 52.2% in patients with PerAF after multiple procedures with a median over 2-year follow-up. Patients with AF duration < 24 months had better outcome. AF duration and ERAF were predictors of LRAF after a single procedure.

Atrial Fibrillation Burden: Moving Beyond Atrial Fibrillation as a Binary Entity: A Scientific Statement From the American Heart Association

Our understanding of the risk factors and complications of atrial fibrillation (AF) is based mostly on studies that have evaluated AF in a binary fashion (present or absent) and have not investigated AF burden. This scientific statement discusses the published literature and knowledge gaps related to methods of defining and measuring AF burden, the relationship of AF burden to cardiovascular and neurological outcomes, and the effect of lifestyle and risk factor modification on AF burden. Many studies examine outcomes by AF burden classified by AF type (paroxysmal versus nonparoxysmal); however, quantitatively, AF burden can be defined by longest duration, number of AF episodes during a monitoring period, and the proportion of time an individual is in AF during a monitoring period (expressed as a percentage). Current guidelines make identical recommendations for anticoagulation regardless of AF pattern or burden; however, a review of recent evidence suggests that higher AF burden is associated with higher risk of stroke. It is unclear whether the risk increases continuously or whether a threshold exists; if a threshold exists, it has not been defined. Higher burden of AF is also associated with higher prevalence and incidence of heart failure and higher risk of mortality, but not necessarily lower quality of life. A structured and comprehensive risk factor management program targeting risk factors, weight loss, and maintenance of a healthy weight appears to be effective in reducing AF burden. Despite this growing understanding of AF burden, research is needed into validation of definitions and measures of AF burden, determination of the threshold of AF burden that results in an increased risk of stroke that warrants anticoagulation, and discovery of the mechanisms underlying the weak temporal correlations of AF and stroke. Moreover, developments in monitoring technologies will likely change the landscape of long-term AF monitoring and could allow better definition of the significance of changes in AF burden over time.

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

Atrial fibrillation (AF), the most common form of arrhythmia, is associated with the prevalence of many common cardiovascular and cerebrovascular diseases. Catheter ablation is considered the first-line therapy for AF; however, AF recurrence is very common after catheter ablation. Studies have been performed to analyze the factors associated with AF recurrence, but none have reached a consistent conclusion on whether left ventricular ejection fraction (LVEF) and left atrial diameter (LA diameter) affect AF recurrence after catheter ablation.The databases PubMed, Embase, and the Cochrane Library were used to search for relevant studies up to September 2017. RevMan 5.3.5 software provided by the Cochrane Collaboration Network was used to conduct this meta-analysis.Thirteen studies involving 2825 patients were included in this meta-analysis. Overall, the results revealed that elevated LA diameter values were significantly associated with AF recurrence in patients after catheter ablation (MD = 2.19, 95% CI: 1.63-2.75, P < .001), while baseline LVEF levels were not significantly positively associated with AF recurrence in patients after catheter ablation (MD = -0.91, 95% CI: -1.18 to 1.67, P = .14).Overall, elevated LA diameter may be associated with AF recurrence after catheter ablation; however, there was no direct relationship between LVEF values and AF recurrence after catheter ablation when baseline LVEF values are normal or mildly decreased. Besides, because of publication bias, further studies should be performed to explore the mechanisms underlying AF recurrence.

The correlation of pulmonary arterial hypertension with late recurrence of paroxysmal atrial fibrillation after catheter ablation

Background

Paroxysmal atrial fibrillation (PAF) is one of the most common clinical arrhythmias. Although radiofrequency catheter ablation (RFCA) for the treatment of atrial fibrillation has continuously matured and developed in recent years, some patients treated with RFCA continued to have atrial fibrillation recurrence, and the recurrence rate was high. Determining indicators to predict the recurrence of PAF after RFCA is significantly important for improving the surgical success rate and guiding clinical work. This study aimed to investigate the influence of pulmonary arterial hypertension (PAH) on the late recurrence of PAF after RFCA.

Methods

A total of 300 patients with PAF, who underwent RFCA for the first time at the Department of Cardiology of Fujian Union Medical College Hospital from January 2013 to October 2016, were retrospectively studied. These patients were regularly followed-up from 3 months at least to 3 years and clinical data were collected. In order to observe the 100 PAF patients with PAH were assigned into the observation group, and 200 PAF patients without PAH were assigned as the control group. PAH and its related clinical characteristics were evaluated by univariate analysis of variance (ANOVA) and logistic regression analysis.

Results

The follow-up results revealed that 34 patients had early recurrence, and the early arrhythmia recurrence rate was 11.3%. Furthermore, 22 patients had late recurrence, including 19 patients with atrial fibrillation and three patients with atrial flutter; and the late recurrence rate was 7.3%. The univariate ANOVA revealed that PAH (P=0.001), early recurrence (P=0.014) and Left atrial diameter (LAD) (P=0.023) had significant effects on late recurrence after PAF ablation. Furthermore, logistic regression analysis revealed that PAH (P=0.049, OR =1.053, 95% CI: 1.000-1.109) was independently correlated to late recurrence of PAF.

Conclusions

PAH is a predictive factor for late recurrence of PAF after RFCA.

A Chromosome 4q25 Variant is Associated with Atrial Fibrillation Recurrence After Catheter Ablation: A Systematic Review and Meta-Analysis

Background

Recent studies suggested that variants on chromosome loci 4q25, 1q21, and 16q22 were associated with atrial fibrillation recurrence after catheter ablation. In this study, we performed a systematic review and meta-analysis to explore the association between variants on chromosome loci 4q25, 1q21, and 16q22 and atrial fibrillation recurrence after catheter ablation.

Methods

We comprehensively searched the databases of MEDLINE and EMBASE from inception to January 2017. Included studies were published prospective or retrospective cohort and case control studies that compared the risk of atrial fibrillation recurrence after catheter ablation in AF patients with chromosome 4q25, 1q21, and 16q22 variants versus no variants. Single-nucleotide polymorphism rs1906617, rs2106261, rs7193343, rs2200733, rs10033464, rs13376333, and rs6843082 were included in this analysis. Data from each study were combined using the random-effects, generic inverse variance method of DerSimonian and Laird to calculate the risk ratios and 95% confidence intervals.

Results

Seven studies from January 2010 to June 2017 involving 3,322 atrial fibrillation patients were included in this meta-analysis. According to the pooled analysis, there was a strong independent association between chromosome 4q25 variant (rs2200733) and the risk of atrial fibrillation recurrence after catheter ablation (risk ratio 1.45 [95% confidence interval 1.15-1.83], P = 0.002). No association was found in other variants.

Conclusion

Our meta-analysis demonstrates a statistically significant increased risk of atrial fibrillation recurrence after catheter ablation in 4q25 variant (only in rs2200733) but not in 1q21 or 16q22 variants.

Left atrial emptying fraction predicts recurrence of atrial fibrillation after radiofrequency catheter ablation

Background

Compared with left atrial (LA) dimension, LA emptying fraction (LAEF) has received less emphasis as a predictor of atrial fibrillation (AF) recurrence after radiofrequency catheter ablation (RFCA). In addition, patients experiencing post-RFCA AF recurrence may respond to previously ineffective antiarrhythmic drugs (AADs). Classifying these patients into a third RFCA outcome category is recommended.

Objective

To identify predictors of RFCA outcome classified into three categories, and to build proportional odds logistic regression models for clinical applicability to predict AF recurrence.

Methods

Data were retrospectively collected from 483 consecutive patients with drug-refractory AF undergoing RFCA (328 men; age 58.4 ± 11.5 years; 383 paroxysmal). Patients were classified into 3 groups based on the last RFCA outcome: group 1, free from AF without AADs; group 2, free from AF with AADs; and group 3, recurrence of AADs-refractory atrial tachyarrhythmia.

Results

After a mean follow-up duration of 64.5 ± 43.2 months and mean ablation procedure number of 1.37 ± 0.68, the RFCA outcome showed 76.0%, 9.5% and 14.5% of patients in groups 1, 2, and 3, respectively. In multivariate analysis, LAEF was the most stable and important predictor of AF recurrence, followed by body mass index, stroke, AF duration, mitral regurgitation, and LA linear ablation. For patients undergoing repeat RFCA, LAEF was the only independent predictor (cutoffs: 43% and 35% for groups 1 and 3, respectively).

Conclusion

LAEF provides optimal prognostic information regarding the risk stratification of AF patients undergoing RFCA.

QTc interval predicts outcome of catheter ablation in paroxysmal atrial fibrillation patients with type 2 diabetes mellitus

Catheter ablation has been recommended as a treatment option for paroxysmal atrial fibrillation (PAF) patients complicated with type 2 diabetes mellitus (T2DM). PAF patients with T2DM have a higher recurrence rate after catheter ablation. Prolongation of corrected QT (QTc) interval has been linked to poor outcomes in T2DM patients. Whether the abnormal QTc interval is associated with the ablation outcome in the PAF patients with T2DM remains unknown. In this study, 134 PAF patients with T2DM undergoing primary catheter ablation were retrospectively enrolled. Pre-procedural QTc interval was corrected by using the Bazett's formula. Cox proportional hazards models were constructed to assess the relationship between QTc interval and the recurrence of AF. After a 29.1-month follow-up period, 61 patients experienced atrial tachyarrhythmia recurrence. Recurrent patients had a longer QTc interval than non-recurrent patients (425.2±21.5 ms vs. 414.1±13.4 ms, P=0.002). Multivariate Cox regression analysis revealed that QTc interval [hazard ratio (HR)=1.026, 95% confidence interval (CI) 1.012-1.040, P=0.005] and left atrial diameter (LAD) (HR=1.125, 95% CI 1.062-1.192, P=0.003) were independent predictors of recurrent atrial tachyarrhythmia. Receiver operating characteristic analysis demonstrated that the cut-off value of QTc (418 ms) predicted arrhythmia recurrence with a sensitivity of 55.7% and a specificity of 69.9%. A combination of LAD and QTc was more effective than LAD alone (P<0.001) in predicting arrhythmia recurrence after the procedure. QTc interval could be used as an independent predictor of arrhythmia recurrence in T2DM patients undergoing AF ablation, thus providing a simple method to identify those patients who likely have a better outcome following the procedure.

Pulmonary Vein Antrum Isolation in Patients With Paroxysmal Atrial Fibrillation: More Than a Decade of Follow-Up

BACKGROUND

We report the outcome of pulmonary vein (PV) antrum isolation in paroxysmal atrial fibrillation (AF) patients over more than a decade of follow-up.

METHODS AND RESULTS

A total of 513 paroxysmal AF patients (age 54±11 years, 73% males) undergoing catheter ablation at our institutions were included in this analysis. PV antrum isolation extended to the posterior wall between PVs plus empirical isolation of the superior vena cava was performed in all. Non-PV triggers were targeted during repeat procedure(s). Follow-up was performed quarterly for the first year and every 6 to 9 months thereafter. The outcome of this study was freedom from recurrent AF/atrial tachycardia. At 12 years, single-procedure arrhythmia-free survival was achieved in 58.7% of patients. Overall, the rate of recurrent arrhythmia (AF/atrial tachycardia) was 21% at 1 year, 11% between 1 and 3 years, 4% between 3 and 6 years, and 5.3% between 6 and 12 years. Repeat procedure was performed in 74% of patients. Reconnection in the PV antrum was found in 31% of patients after a single procedure and in no patients after 2 procedures. Non-PV triggers were found and targeted in all patients presenting with recurrent arrhythmia after ≥2 procedures. At 12 years, after multiple procedures, freedom from recurrent AF/atrial tachycardia was achieved in 87%.

CONCLUSIONS

In patients with paroxysmal AF undergoing extended PV antrum isolation, the rate of late recurrence is lower than what previously reported with segmental or less extensive antral isolation. However, over more than a decade of follow-up, nearly 14% of patients developed recurrence because of new non-PV triggers.

Clinical significance of nutritional status in patients with atrial fibrillation: An overview of current evidence

BACKGROUND

Obesity is a well-known atherosclerosis risk factor; however, its role and the importance of undernutrition in atrial fibrillation (AF) pathogenesis are still not well understood. The aim of this study was to present the current state of knowledge on this issue in different groups of patients.

METHODS

Systematic review of papers published between 1980 and 2016.

RESULTS

The literature shows contradicting views regarding the impact of nutritional status on the risk, course, and complications of AF. On the one hand, it has been revealed that overweight, obesity, and high birth mass increase the risk of AF, and that their reduction is linked to an improved course of AF and reduced all-cause and cardiovascular mortality. On the other hand, a so-called obesity paradox has been found, which shows lower all-cause mortality in overweight patients with AF compared to those of normal weight or who are underweight. It has also been shown, although based on a small number of studies, that the relationship between nutritional status and risk of AF and its complication may be U-shaped, which means that not only patients with obesity, but also individuals with underweight, cachexia, and low birth weight may have an increased risk and poor outcome of AF.

CONCLUSIONS

The relationship between patients' nutritional status and the course of AF has become clearer but it requires further studies examining the importance of weight reduction on AF course.

Short-term Antiarrhythmic Drugs After Catheter Ablation for Atrial Fibrillation: A Meta-analysis of Randomized Controlled Trials

BACKGROUND

The incidence of recurrent arrhythmia after catheter ablation (CA) for atrial fibrillation (AF) is unacceptable. Short-term antiarrhythmic drug (AAD) treatment following CA was presumed to be effective in reducing recurrent arrhythmia.

OBJECTIVE

To fully evaluate the efficacy of short-term use of AADs following CA for AF in preventing recurrence of atrial tachyarrhythmias.

METHODS

PubMed, Embase, Cochrane Library, and ClinicalTrials.gov were searched up until May 1, 2016. We enrolled randomized controlled trials (RCTs) that evaluated the efficacy of short-term use of AADs following CA for AF in preventing early and/or late recurrence of atrial tachyarrhythmias. The statistical analyses were performed using Review Manager Version 5.3.

RESULTS

Six RCTs were included in this analysis, involving a total of 2764 patients. The frequency of early recurrence of atrial tachyarrhythmias was 39.5% in the AAD group (556 of 1407) and 47.2% (640 of 1357) in the control group. The pooled risk ratio of the AAD group to the control group was 0.78 (95% CI = 0.62-0.98). Regarding late recurrence of AF (LRAF), the incidence in the AAD group and the control group was 32.5% (420 of 1293) and 34.6% (450 of 1300), respectively. No significant difference was identified between the 2 groups (relative risk = 0.94, 95% CI = 0.85-1.05).

CONCLUSIONS

Short-term use of AADs following CA for AF reduced the incidence of early recurrent atrial tachyarrhythmias but did not prevent LRAF.

Administration of antiarrhythmic drugs to maintain sinus rhythm after catheter ablation for atrial fibrillation: a meta-analysis

BACKGROUND

Whether the short-term administration of antiarrhythmic drugs (AADs) to maintain sinus rhythm following catheter ablation (CA) for atrial fibrillation (AF) can prevent the recurrence of AF is still a matter of debate. We searched the PubMed database and the Cochrane Library, and compiled a list of retrieved articles. We included only randomised controlled trials(RCTs) that compared any AADs against control (placebo or no treatment) or other AADs following CA for AF. Statistical analysis of the odds ratio (OR) and corresponding 95% confidence interval (CI) were used to determine the overall effect of both outcomes. The Mantel-Haenszel method was used to pool data of the outcomes of AF recurrence into fixed effect model meta-analyses.

AIMS

We performed a systematic review to determine the effectiveness of short-term treatment with AADs on the recurrence of AF after CA.

RESULTS

Six RCTs were included in this study, with a total of 814 patients. Post-procedural temporary administration of AADs in patients after CA for AF reduced the early recurrence of AF (antiarrhythmic drug 103 patients [25.3%], control 162 patients [39.8%]; OR 0.47 [95% CI 0.34-0.64]; χ(2)  = 3.77; P = 0.58; I(2)  = 0%). No significant difference in patients after CA for AF in the late recurrence of AF (antiarrhythmic drug 148 patients [36.5%], control 171 patients [42.5%]; OR 0.77 [95% CI 0.57-1.03]; χ(2)  = 3.15; P = 0.68; I(2)  = 0%). The heterogeneity was zero in both analyses.

CONCLUSION

Although the continued administration of AADs after CA for AF can decrease early atrial tachycardias (ATa), this treatment does not prevent late ATa.

Analysis of Bipolar Radiofrequency Ablation in Treatment of Atrial Fibrillation Associated with Rheumatic Heart Disease

Background

Among patients with rheumatic heart disease (RHD), 45% to 60% present with atrial fibrillation (AF), which is associated with increased rates of thromboembolism, heart failure, and even death. The bipolar radiofrequency ablation (BRFA) combining with mitral valve procedure has been adopted in patients of AF associated with RHD, but evaluations about its effectiveness are still limited.

Methods

A total of 87 patients with RHD and long persistent AF who had accepted mitral valve replacement concomitant with BRFA were studied. Clinical data were collected to analyze the midterm results of BRFA and evaluate its efficiency. Univariate and multivariate analyses were used to identify the independent factors associated with late AF recurrence.

Results

Sixty-six (75.9%) patients maintained sinus rhythm after a mean follow-up of 13.4 ± 5.2 months. Late AF recurrence had been detected in 21 (24.1%) patients, 11 (12.6%) patients were confirmed to be AF, 8 (9.2%) patients were atrial flutter and 2 (2.3%) patients were junctional rhythm. In Multivariate logistic regression analysis, body mass index (BMI) (OR = 1.756, 95% CI = 1.289–2.391, p = 0.000) and early AF recurrence (OR = 5.479, 95% CI = 1.189–25.254, p = 0.029) were independent predictors of late AF recurrence. In addition, left ventricular ejection fraction (LVEF) and New York Heart Association class showed a greater improvement in patients who maintained sinus rhythm than those who experienced late AF recurrence.

Conclusion

BRFA is an effective technique for the treatment of long persistent AF associated with RHD during mitral valve replacement. The BMI and early AF recurrence are independent predictors for late AF recurrence. Patients with long-term restoration of sinus rhythm experienced a greater improvement of left ventricular function after BRFA.

MicroRNA profiling in the left atrium in patients with non-valvular paroxysmal atrial fibrillation

Background

We aimed to identify the miRNA expression profiles in left atrial appendage, with the intention of identifying miRNAs that were significantly associated with non-valvular paroxysmal AF.

Methods

The RNA samples were isolated from healthy controls (n = 5) and patients with atrial fibrillation (n = 8). To confirm the findings obtained by analyzing the miRNA profile, we measured the expression of selected miRNAs in the entire cohort by quantitative PCR.

Results

Ten specific miRNAs were found to be differentially expressed between atrial fibrillation and healthy controls with more than a 2-fold change (P < 0.05). Consistent with the data obtained for the profile, expression levels of miRNA-155, miRNA-146b-5p and miRNA-19b were significantly increased in patients with atrial fibrillation. Interestingly, levels of miRNA-146b-5p and miRNA-155, which are known to be associated with inflammation, were independently and positively associated with left atrium dimension, atrial fibrillation duration and high sensitivity C-reactive protein levels. By using four Databases (TargetScan, miRanda, Starbase Clip-seq and miRDB) to perform target gene prediction, there were four genes were related to the inflammatory response and fibrosis, and three others encoding cardiac ion channel proteins. As a result of TaqMan qPCR and Western analysis, the relative mRNA and protein expression level of three target genes (DIER-1, TIMP-4 and CACNA1C) were significantly lower in the atrial fibrillation group than that in the healthy control group.

Conclusions

Expression of inflammation-associated miRNAs is significantly up-regulated in the left atrial appendage of patients with non-valvular paroxysmal atrial fibrillation, which may play a significant role in electrical and structural remodeling.

Electronic supplementary material

The online version of this article (doi:10.1186/s12872-015-0085-2) contains supplementary material, which is available to authorized users.