Prevention of atrial fibrillation recurrence with corticosteroids after radiofrequency catheter ablation: a randomized controlled trial

2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society expert consensus statement on catheter and surgical ablation of atrial fibrillation

In the last three decades, ablation of atrial fibrillation (AF) has become an evidence-based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society, the Asia Pacific Heart Rhythm Society, and the Latin American Heart Rhythm Society.

Long-term clinical impact of early recurrence of atrial tachyarrhythmia after cryoballoon ablation in patients with atrial fibrillation

INTRODUCTION

The impact of early recurrence of atrial tachyarrhythmia (ERAT) within the 90-day blanking period on long-term outcomes in atrial fibrillation (AF) patients undergoing cryoballoon ablation (CBA) is controversial. This study aimed to assess the relationship between ERAT and late recurrence of atrial tachyarrhythmia (LRAT) post-CBA.

METHODS

Utilizing data from a multicenter registry in Korea (May 2018 to June 2022), we analyzed the presence and timing of ERAT (<30, 30-60, and 60-90 days) and its association with LRAT risk after CBA. LRAT was defined as any recurrence of AF, atrial flutter, or atrial tachycardia lasting more than 30 s beyond the 90 days.

RESULTS

Out of 2636 patients, 745 (28.2%) experienced ERAT post-CBA. Over an average follow-up period of 21.2 ± 10.3 months, LRAT was observed in 874 (33.1%) patients. Patients with ERAT had significantly lower 1-year LRAT freedom compared to those without ERAT (42.6% vs. 85.5%, p < .001). Multivariate analysis identified ERAT as a potential predictor of LRAT, with a hazard ratio (HR) of 3.98 (95% confidence interval [CI], 3.47-4.57). Significant associations were noted across all examined time frames (HR, 3.84; 95% CI, 3.32-4.45 in <30 days, HR, 5.53; 95% CI, 4.13-7.42 in 30-60 days, and HR, 4.29; 95% CI, 3.12-5.89 in 60-90 days). This finding was consistently observed across all types of AF.

CONCLUSION

ERAT during the 90-day blanking period strongly predicts LRAT in AF patients undergoing CBA, indicating a need to reconsider the clinical significance of this period.

2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society expert consensus statement on catheter and surgical ablation of atrial fibrillation

In the last three decades, ablation of atrial fibrillation (AF) has become an evidence-based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society (HRS), the Asia Pacific HRS, and the Latin American HRS.

The efficacy of colchicine in preventing atrial fibrillation recurrence and pericarditis post-catheter ablation for atrial fibrillation - A systematic review and meta-analysis of prospective studies

Introduction

Catheter ablation (CA) initiates a proinflammatory process responsible for atrial fibrillation (AF) recurrence (25-40%) and pericarditis (0.8%). Due to its anti-inflammatory properties, colchicine, a microtubule inhibitor, is explored for the prevention of early AF recurrence and pericarditis after pulmonary vein isolation. We performed a pooled analysis to determine the rates of AF recurrence and pericarditis after CA in patients receiving colchicine.

Methods

A comprehensive literature review was conducted on PubMed and SCOPUS from inception to December 2023 using medical subject headings and keywords, followed by a citation and reference search. We identified prospective studies reporting recurrent AF and pericarditis outcomes after catheter ablation in patients taking colchicine versus placebo. A binary random effects model was used to estimate pooled odds ratios and 95% confidence intervals. Sensitivity analysis was conducted using the leave-one-out method, and heterogeneity was assessed using the I2 statistic.

Results

Of the 958 identified studies, 4 met our inclusion criteria. A total of 1,619 patients were analyzed; 743 received colchicine, and 875 were in the placebo group. Recurrent AF after CA occurred in 192 (29.0 %) of the colchicine group and 318 (39.5 %) of the placebo group. Post-ablation pericarditis occurred in 34 (5.3 %) of the colchicine group and 128 (16.5 %) of the placebo group. Pooled analysis of prospective studies showed that colchicine decreased the odds of recurrent AF [OR: 0.63 (95 % CI: 0.50-0.78), p < 0.01, I2  = 8 %] and post-ablation pericarditis [OR: 0.34 (95 % CI: 0.16-0.75), p < 0.01, I2  = 57 %]. Odds of GI disturbance were increased with colchicine use in our analysis [OR: 2.77 (95 % CI: 1.17-6.56), p = 0.02, I2  = 84 %].

Conclusion

Colchicine use is associated with decreased odds of recurrent AF and pericarditis post-CA from the analysis of prospective studies. These results underscore the potential for colchicine therapy for future exploration with randomized and controlled research with different dosages.

DNA Framework-Enabled 3D Organization of Antiarrhythmic Drugs for Radiofrequency Catheter Ablation

Preorganizing molecular drugs within a microenvironment is crucial for the development of efficient and controllable therapeutic systems. Here, the use of tetrahedral DNA framework (TDF) is reported to preorganize antiarrhythmic drugs (herein doxorubicin, Dox) in 3D for catheter ablation, a minimally invasive treatment for fast heartbeats, aiming to address potential complications linked to collateral tissue damage and the post-ablation atrial fibrillation (AF) recurrence resulting from incomplete ablation. Dox preorganization within TDF transforms its random distribution into a confined, regular spatial arrangement governed by DNA. This, combined with the high affinity between Dox and DNA, significantly increases local Dox concentration. The exceptional capacity of TDF for cellular internalization leads to a 5.5-fold increase in intracellular Dox amount within cardiomyocytes, effectively promoting cellular apoptosis. In vivo investigations demonstrate that administering TDF-Dox reduces the recurrence rate of electrical conduction after radiofrequency catheter ablation (RFCA) to 37.5%, compared with the 77.8% recurrence rate in the free Dox-treated group. Notably, the employed Dox dosage exhibits negligible adverse effects in vivo. This study presents a promising treatment paradigm that strengthens the efficacy of catheter ablation and opens a new avenue for reconciling the paradox of ablation efficacy and collateral damage.

Association between inflammation markers and all-cause mortality in critical ill patients with atrial fibrillation: Analysis of the Multi-Parameter Intelligent Monitoring in Intensive Care (MIMIC-IV) database

Background

Inflammation is related to cardiovascular disease. Among the many inflammatory markers, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and systemic immune-inflammatory index (SII) were considered as novel predictors for atherosclerosis outcomes. We aimed to investigate the impact of these inflammatory markers on the prognosis of patients with atrial fibrillation (AF).

Methods

We obtained data on AF patients from the Medical Information Mart for Intensive Care (MIMIC)-IV database. These patients were classified into two groups based on their survival status within 30 days. Then, they were divided into three groups based on the tertile of baseline NLR, PLR, and SII, respectively. We comprehensively explored the relationship between those inflammatory indicators and all-cause mortality in patients with AF by Kaplan-Meier analysis, multivariate Cox regression analysis, receiver operating characteristic (ROC) analyses, restricted cubic spline regression (RCS), and subgroup analysis.

Results

A total of 4562 patients with AF were included. Statistically significant differences were found between survivor and non-survivor groups for NLR, PLR and SII. Patients in the high tertile of the NLR had a higher mortality rate than those in the low and intermediate tertiles, as did patients in the PLR and the SII. NLR, PLR and SII were independently associated with increased risk of all-cause mortality. RCS showed that the 30-day and 365-day risk of death were linearly associated with increases in NLR, PLR, and SII, respectively.

Conclusion

NLR, PLR, and SII have the potential to be used as indicators for stratifying the risk of mortality in critically ill patients with AF.

2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society expert consensus statement on catheter and surgical ablation of atrial fibrillation

In the last three decades, ablation of atrial fibrillation (AF) has become an evidence-based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society, the Asia Pacific Heart Rhythm Society, and the Latin American Heart Rhythm Society .

Reconsideration of the definition of blanking period and significance of early recurrences after catheter ablation of atrial fibrillation

PURPOSE OF REVIEW

Early recurrence of atrial tachyarrhythmia (ERAT) during blanking period (BP) is not uncommon after catheter ablation of AF. Current guidelines and consensus statements recommend conservative treatment of ERAT. This review summarized recent studies, underlying mechanism and clinical managements of ERAT, and proposed a reconsideration of the definition and clinical significance of BP.

RECENT FINDINGS

Recent studies have shown that the entity of ERAT in the very early phase of BP (i.e., first 4 weeks of the 3-month period) is different from those ERATs occurring late which is strongly associated with the late recurrence of atrial tachyarrhythmia. The optimal BP duration suggested by clinical observation ranges from 21 to 58 days. Using antiarrhythmic drugs and early electrical cardioversion are the effective management for ERAT, whereas re-ablation is a reasonable strategy although remains controversial.

SUMMARY

The definition of BP with a shorter duration, that is, 1 month instead of 3 months post AF ablation, is supported by the observations of latest clinical studies. Recurrent atrial tachyarrhythmia beyond the 1-month time frame is associated with higher risk of late recurrence and may warrant repeat ablation. A revisit to the guideline recommendation on management of ERAT is needed to change clinical practice.

Early recurrence of atrial tachyarrhythmia indicates pulmonary vein reconduction independent of blanking period duration in the RACE-AF trial

INTRODUCTION

Atrial tachyarrhythmia recurrence during the blanking period (early ATA) after pulmonary vein isolation (PVI) is associated with an increased risk of later recurrence, but its relationship with pulmonary vein reconduction (PVR) is poorly understood. The objective of the present study was to evaluate the relationship between early ATA and PVR. Second, to provide data on the optimal blanking period by (a) evaluating how the predictive values of ATA for PVR are affected by blanking period duration, and (b) assessing the temporal development in atrial fibrillation (AF) burden.

METHODS

In this RACE-AF substudy, 91 patients with paroxysmal AF undergoing PVI randomized to radiofrequency or cryoballoon ablation were included. All patients received an implantable cardiac monitor and underwent a protocol-mandated repeat procedure after 4-6 months for assessment of PVR. ATA ≥ 30 s. ≤ 90 days after PVI constituted early ATA.

RESULTS

PVR was found in 37/54 (69%) patients with early ATA and in 11/37 (30%) patients without (p < .001). The positive predictive value of ATA for PVR was independent of blanking period duration (range 0-90 days). In both patients with and without PVR, AF burden was higher in the first month after PVI, but AF burden from the second month was similar to AF burden after the conventional blanking period.

CONCLUSION

Early ATA indicates PVR, and the positive predictive value is independent of the blanking period duration. Altogether, the results of this study support substantially shortening the blanking period after PVI for paroxysmal AF.

Colchicine for the Prevention of Recurrent Arrhythmia After Catheter Ablation of Atrial Fibrillation: Results of a Single-Center, Retrospective Study

BACKGROUND

There is evidence to suggest that colchicine reduces the risk of recurrent atrial fibrillation (AF) after catheter ablation; however, the tolerability and safety of colchicine in routine practice is unknown.

METHODS

Patients undergoing catheter ablation for AF who received colchicine after ablation were matched 1:1 to patients who did not by age, sex, and renal function. Recurrent AF was compared between groups categorically at 12 months and via propensity weighted Cox proportional hazards models with and without a 3-month blanking period.

RESULTS

Overall, 180 patients (n = 90 colchicine and n = 90 matched controls) were followed for a median (Q1, Q3) of 10.3 (7.0, 12.0) months. Mean age was 65.3 ± 9.1 years, 33.9% were women, mean CHA2DS2-VASc score was 2.9 ± 1.5, and 51.1% had persistent AF. Most patients (70%) received colchicine 0.6 mg daily for a median of 30 days. In the colchicine group, 55 patients (61.1%) were receiving at least one known interacting medication with colchicine. After ablation, one patient required colchicine dose reduction and four patients required discontinuation. After adjusting for covariate imbalance using propensity weighting, no significant association between colchicine use and AF recurrence was identified (adjusted hazard ratio 0.94, 95% confidence interval [CI] 0.48-1.85; p = 0.853). No significant association was found between colchicine use and all-cause hospitalizations (adjusted odds ratio 0.74, 95% CI 0.28-1.96; p = 0.548).

CONCLUSION

Despite the frequent presence of drug-drug interactions, a 30-day course of colchicine is well-tolerated after AF ablation; however, we did not observe any association between colchicine and lower rates of AF recurrence or hospitalization.

Prevalence, Associated Factors, and Echocardiographic Estimation of Left Atrial Hypertension in Patients With Atrial Fibrillation

Background Elevated left atrial (LA) pressure predisposes individuals to the initiation and persistence of atrial fibrillation (AF), and LA hypertension is associated with AF recurrence after catheter ablation (CA). However, the exact frequency and factors associated with LA hypertension are unknown, and its noninvasive estimation is challenging. This study aimed to investigate the prevalence and determinants of LA hypertension in patients with AF who underwent first CA. Methods and Results We examined 183 patients with AF who underwent conventional and speckle-tracking echocardiography before CA to assess LA size, reservoir strain, and stiffness. Direct LA pressure was measured at the time of CA, and LA hypertension was defined as mean LA pressure >15 mm Hg. Thirty-three (18.0%) patients exhibited LA hypertension. Patients with LA hypertension had a significantly larger LA volume index (40.2 [28.4-52.1] versus 34.1 [26.9-42.4] mL/m2, P=0.025), reduced LA reservoir strain (15.1 [10.4-21.7] versus 22.7 [14.4-32.3] %, P=0.002) and increased LA stiffness (0.69 [0.34-0.99] versus 0.36 [0.24-0.54], P<0.001). Multivariable analyses showed that waist circumference, C-reactive protein level, LA reservoir strain, and LA stiffness were independently associated with LA hypertension (all P<0.05), while LA volume and E/e' ratio were not. Among echocardiographic parameters, receiver operating characteristic curve analysis identified LA stiffness as the best predictor of LA hypertension. Conclusions Approximately 20% of patients with AF who underwent CA had LA hypertension. Central obesity and inflammation might be involved in the pathophysiological mechanisms of LA hypertension, and echocardiography-derived LA stiffness may have clinical utility for the detection of LA hypertension before CA.

Blanking period antiarrhythmic drugs after catheter ablation for atrial fibrillation: a meta-analysis of randomized controlled trials

Background

Antiarrhythmic drugs (AADs) are frequently prescribed following catheter ablation (CA) for atrial fibrillation (AF). However, to date, there is a lack of large-scale, multicenter controlled studies that have confirmed the efficacy of AADs in reducing the incidence of late recurrence of AF after CA. Furthermore, the optimal duration of short-term use of AADs after CA remains a controversial topic.

Methods

PubMed, Embase, Cochrane Library, CNKI, and ClinicalTrials.gov were searched until April 25, 2022. We conducted a meta-analysis of randomized controlled trials (RCTs) to assess the efficacy of blanking period AADs in predicting both early and late recurrence of AF. In addition, Grading of Recommendations Assessment, Development and Evaluation (GRADE) was used to assess the quality of evidence in this meta-analysis.

Results

12 RCTs with 3,625 patients were included in this meta-analysis. Short-term use of AADs after AF ablation reduced the risk of early recurrence of AF compared with the no-AADs group. In the subgroup analysis of AADs use time, it was found that only using AADs for more than 2 months can reduce the early recurrence of AF after CA. However, when compared with the no-AADs group, short-term use of AADs after CA did not reduce the incidence of late recurrence of AF.

Conclusions

Short-term use of AADs (more than 2 months) can reduce the early recurrence but not the late recurrence of AF after CA.

Spirometry in atrial fibrillation: what's the catch?

INTRODUCTION

People with COPD rarely have COPD alone, and the commonest co-morbidities occurring with COPD are cardiovascular. Whilst multiple studies have explored the association between major cardiovascular events and COPD, less attention has been paid to arrhythmias, specifically atrial fibrillation (AF). AF and COPD frequently occur together, posing challenges in diagnosis and management. In this review, we describe the relationship between AF and COPD epidemiologically and physiologically, demonstrating the role of spirometry as a diagnostic and disease management tool.

AREAS COVERED

We provide epidemiological evidence that COPD and AF are independent risk factors for one another, that either disease is highly prevalent amongst people with the other, and that they have shared risk factors; all of which contribute to adverse prognostic. We elucidated common pathophysiological mechanisms implicated in AF-COPD. We ultimately present the epidemiological and physiological evidence with a view to highlight specific areas where we feel spirometry is of value in the management of AF-COPD.

EXPERT OPINION

AF and COPD commonly co-occur, there is often diagnostic delay, increased risk of reduced cardioversion success, and missed opportunity to intervene to reduce stroke risk. Greater awareness and timelier diagnosis and guideline directed management may improve outcomes for people with both diseases.

Comparison of Radiofrequency and Cryoballoon Pulmonary Vein Ablation for the Early and Late Recurrence of Atrial Fibrillation

Objective Early recurrence (ER) after pulmonary vein isolation (PVI) for atrial fibrillation (AF) is expected to resolve within the recommended 3-month blanking period, irrespective of the ablation device used. To compare the occurrence and relationship of AF within the blanking period and subsequent late recurrence (LR) with radiofrequency (RF) and cryoballoon (CB) ablation. Methods A retrospective analysis of 294 patients (mean age=62±9, 70.0% male) undergoing PVI for drug-refractory paroxysmal AF was done. After categorizing the patients into the RF group (n=152) and the CB group (n=142), a group-wise comparison was done to investigate the impact of ER on LR throughout a 2-year follow-up. Results The groups were similar regarding the occurrence of ER (RF=22.4%, CB=24.6%, p=0.62), while LR was significantly higher in the RF group (p=0.003). ER was associated with LR in the RF group (p<0.01) but not in the CB group (p=0.08), while a significant independent association with an increased LR risk was observed [hazard ratio (HR) 6.12; 95% confidence interval (CI) 3.56-10.51, p<0.01]. RF ablation also significantly increased the risk of LR (HR=2.93; 95% CI=1.64-5.23, p<0.01). Conclusion A recurrence of atrial arrhythmia is more frequent with RF-PVI than with CB-PVI for patients with paroxysmal AF. ER and RF-ablation are strong predictors for LR after the 3-month blanking period.

The atrial fibrillation burden during the blanking period is predictive of time to recurrence after catheter ablation

Objective

This study aimed to assess whether atrial fibrillation (AF) occurrence or its corresponding daily mean burden (in minutes/day) during the mid to late blanking period after pulmonary vein isolation (PVI), predicts AF recurrence.

Methods

Analysis of consecutive first PVI ablation patients undergoing prolonged electrocardiogram (ECG) monitoring during the second and third months after PVI. The clinical variables, total AF burden, and their relationship with time to recurrence were studied.

Results

477 patients with a mean age of 56.9 (SD = 12.3) years (63.7 % male; 71.7 % paroxysmal AF), from which 317 (66.5 %) had an external event recorder between 30 and 90 days after ablation. Median follow-up of 16.0 (P 25:12.0: P 75:33.0) months, 177 (37 %) patients had an AF recurrence, with 106 (22.2 %) having the first episode after 12 months of follow-up. In the group of patients with an event recorder, 80 (25.2 %) had AF documented during the blanking period. Multivariable analysis showed that AF during the blanking period was associated with a 4-fold higher risk of recurrence (HR: 3.98; 95 %CI: 2.95–5.37), and, compared to patients in sinus rhythm, those with an AF burden ≥ 23 min/day had an approximately 7-fold higher risk of recurrence (HR estimate: 6.79; 95 %CI: 4.56–10.10).

Conclusions

The probability of experiencing AF recurrence can be predicted by atrial tachyarrhythmia episodes during the second and third months after PVI. Atrial arrhythmias burden > 23 min/day has a high predictive ability for recurrence.

Early recurrence after cryoballoon versus radiofrequency ablation for paroxysmal atrial fibrillation: mechanism and implication in long-term outcome

Background

Early recurrence (ER) after catheter ablation for atrial fibrillation (AF) has been considered as a common phenomenon but its mechanism and implication in long-term outcome has not been fully elucidated. We aimed to clarify the relation between post-ablation inflammation and ER after cryoballoon ablation (CBA) or radio-frequency ablation (RFA) and evaluate the clinical significance of ER.

Methods

A total of 154 patients with paroxysmal AF undergoing ablation were consecutively recruited, including 90 patients undergoing RFA (RF group) and 64 patients undergoing CBA (CB group). Myocardial injury and inflammation biomarkers were analyzed before and 6 h, 24 h and 48 h after ablation. Acute early recurrence (AER), non-acute early recurrence (NAER) and late recurrence (LR) was defined as recurrence of atrial tachyarrhythmia during 0–3, 4–90 days and beyond a 90-day blanking period after ablation.

Results

Cardiac troponin I was significantly higher in CB group while C reactive protein (CRP) and Ratio Neutrophil/Lymphocyte were more elevated in RF group. Higher CRP level after RFA was significantly associated with AER in RF group and lower CRP level after CBA was predictive of AER in CB group. In addition, average cryoablation duration was positively correlated with CRP level after CB group. Cox regression revealed that NAER and left atrial diameter were associated with LR in RF group, while AER and NAER were predictive of LR after CBA.

Conclusions

Post-ablation inflammation was greater in RFA than in CBA. Excessive inflammatory response may be an important factor of AER after RFA. AER after CBA was related with lower inflammation and predictive of LR. Further investigations are still warranted to address on these findings.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-022-02816-1.

Localized Myocardial Anti-Inflammatory Effects of Temperature-Sensitive Budesonide Nanoparticles during Radiofrequency Catheter Ablation

Radiofrequency (RF) catheter ablation has emerged as an effective alternative for the treatment of atrial fibrillation (AF), but ablation lesions will result in swelling and hematoma of local surrounding tissue, triggering inflammatory cell infiltration and increased release of inflammatory cytokines. Some studies have shown that the inflammatory response may be related to the early occurrence of AF. The most direct way to inhibit perioperative inflammation is to use anti-inflammatory drugs such as glucocorticoids. Here, we prepared polylactic-co-glycolic acid (PLGA) nanoparticles loaded with budesonide (BUD) and delivered them through irrigation of saline during the onset of ablation. Local high temperature promoted local rupture of PLGA nanoparticles, releasing BUD, and produced a timely and effective local myocardial anti-inflammatory effect, resulting in the reduction of acute hematoma and inflammatory cell infiltration and the enhancement of ablation effect. Nanoparticles would also infiltrate into the local myocardium and gradually release BUD ingredients to produce a continuous anti-inflammatory effect in the next few days. This resulted in a decrease in the level of inflammatory cytokine IL-6 and an increase of anti-inflammatory cytokine IL-10. This study explored an extraordinary drug delivery strategy to reduce ablation-related inflammation, which may prevent early recurrence of AF.

Prednisone Ameliorates Atrial Inflammation and Fibrosis in Atrial Tachypacing Dogs

Atrial inflammation and fibrosis have long been considered culprits in the development of atrial fibrillation (AF). Prior clinical studies showed that corticosteroid therapy is beneficial in patients with AF. Here we sought to determine whether prednisone treatment prevents atrial tachypacing (ATP) induced atrial fibrosis.Dogs were randomized into the sham, ATP, ATP + low-dose prednisone (ALP), and ATP + high-dose prednisone (AHP) groups. After 6 days of recovery from surgery, dogs were subjected to ATP at 400 beats per minute for 4 weeks while being treated with prednisone (15 or 40 mg/day) or a placebo. Pacemakers were not activated in the sham group.Compared with the ATP group, the expression of collagen I, collagen III, α-smooth muscle actin, transforming growth factor-β1 and connective tissue growth factor were significantly reduced in the ALP and AHP groups. Fluorescence assays showed that reactive oxygen species formation in the right atrium was suppressed in the ALP and AHP groups compared with the ATP group. The protein level of NADPH oxidase 2 was reduced in the ALP and AHP groups' versus ATP group, while NOX4 and NOX5 were unchanged. ATP-induced downregulation of BH4 and eNOS uncoupling in the atria was partially restored in the prednisone-treated groups.Our study demonstrated that atrial fibrosis induced by ATP were suppressed by prednisone. Low-dose prednisone was also effective in suppressing the development of atrial fibrosis.

The role of inflammation in the pathogenesis and treatment of arrhythmias

The pathogenesis of arrhythmias is complex and multifactorial. The role of inflammation in the pathogenesis of both atrial and ventricular arrhythmias (VA) has been explored. However, developing successful pharmacotherapy regimens based on those pathways has proven more of a challenge. This narrative review provides an overview of five common arrhythmias impacted by inflammation, including atrial fibrillation (AF), myocardial infarction, arrhythmogenic cardiomyopathy, cardiac sarcoidosis, and QT prolongation, and the potential role for anti-inflammatory therapy in their management. We identified arrhythmias and arrhythmogenic disease states with the most evidence linking pathogenesis to inflammation and conducted comprehensive searches of United States National Library of Medicine MEDLINE^® and PubMed databases. Although a variety of agents have been studied for the management of AF, primarily in an effort to reduce postoperative AF following cardiac surgery, no standard anti-inflammatory agents are used in clinical practice at this time. Although inflammation following myocardial infarction may contribute to the development of VA, there is no clear benefit with the use of anti-inflammatory agents at this time. Similarly, although inflammation is clearly linked to the development of arrhythmias in arrhythmogenic cardiomyopathy, data demonstrating a benefit with anti-inflammatory agents are limited. Cardiac sarcoidosis, an infiltrative disease eliciting an immune response, is primarily treated by immunosuppressive therapy and steroids, despite a lack of primary literature to support such regimens. In this case, anti-inflammatory agents are frequently used in clinical practice. The pathophysiology of arrhythmias is complex, and inflammation likely plays a role in both onset and duration, however, for most arrhythmias the role of pharmacotherapy targeting inflammation remains unclear.

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.

The Blinding Period Following Ablation Therapy for Atrial Fibrillation: Proarrhythmic and Antiarrhythmic Pathophysiological Mechanisms

Atrial fibrillation (AF) causes heart failure, ischemic strokes, and poor quality of life. The number of patients with AF is estimated to increase to 18 million in Europe in 2050. Pharmacological therapy does not cure AF in all patients. Ablative pulmonary vein isolation is recommended for patients with drug-resistant symptomatic paroxysmal AF but is successful in only about 60%. In patients in whom ablative therapy is successful on the long term, recurrence of AF may occur in the first weeks to months after pulmonary vein ablation. The early recurrence (or delayed cure) of AF is not understood but forms the basis for the generally accepted 3-month blinding (or blanking) period after ablation therapy, which is not included in the evaluation of the eventual success rate of the procedures. The underlying pathophysiological processes responsible for early recurrence and the delayed cure are unknown. The implicit assumption of the blinding period is that the AF mechanism in this period is different from the ablation-targeted AF mechanism (ectopy from the pulmonary veins). In this review, we evaluate the temporary and long-lasting pro- and antiarrhythmic effects of each of the pathophysiological processes and interventions (necrosis, ischemia, oxidative stress, edema, inflammation, autonomic nervous activity, tissue repair, mechanical remodeling, and use of antiarrhythmic drugs) occurring in the blinding period that can modulate AF mechanisms. We propose that stretch-reducing ablation scar is a permanent antiarrhythmic mechanism that develops during the blinding period and is the reason for delayed cure.

Inflammation, atrial fibrillation, and the potential role for colchicine therapy

Increasing evidence suggests that the "NACHT-LRR and PYD domain-containing protein 3" (NLRP3) inflammasome plays an important role in atherosclerotic cardiovascular disease (ASCVD). Recent preclinical evidence has suggested that the NLRP3 inflammasome may play a prominent role in the pathogenesis of atrial fibrillation (AF). As such, the therapies that have shown efficacy in reducing ASCVD events may also prove beneficial in AF. In this article, we review the findings that implicate the NLRP3 inflammasome in the pathogenesis of AF, discuss existing evidence behind the use of anti-inflammatory agents for AF, and discuss the future role that colchicine and other anti-inflammatory agents may play in the prevention and treatment of AF.

Impact of myocardial injury and inflammation due to ablation on the short-term and mid-term outcomes: Cryoballoon versus laser balloon ablation

BACKGROUND

Cryoballoon ablation (CBA) and laser balloon ablation (LBA) were developed as alternatives to conventional radiofrequency ablation for paroxysmal atrial fibrillation (PAF). Pathological findings after ablation such as myocardial injury and inflammation are thought to be different between CBA and LBA. However, the different impact of myocardial injury and inflammation after ablation on short- and mid-term outcomes remains unclear.

METHODS

Consecutive PAF patients who underwent CBA and LBA were enrolled from the Osaka Rosai Atrial Fibrillation ablation (ORAF) registry. The difference of the acute myocardial injury marker (hs-TnI), and changes of inflammation markers (C reactive protein; ΔCRP, and white blood cell; ΔWBC) after catheter ablation and the difference of the short-term (within 3 months after ablation) and mid-term (from 3 months to 6 months after ablation) outcomes were evaluated between the two groups.

RESULTS

The CBA and LBA groups consisted of 55 and 56 patients, respectively. After propensity score matching, CBA and LBA groups consisted of 37 patients, respectively. Hs-TnI value was significantly higher in CBA than LBA group, while ΔCRP and ΔWBC were significantly higher in LBA than CBA group. In the propensity score-matched pairs, the LBA group had a significantly greater risk of short-term arrhythmia recurrence than the CBA group, whereas no significant difference of mid-term arrhythmia recurrence were found between the two groups.

CONCLUSION

Myocardial injury and inflammation status differ between CBA and LBA groups. LBA group had stronger inflammation after ablation and had a significantly greater risk of short-term arrhythmia recurrence after PVI than CBA group.

Impact of bisoprolol transdermal patch on early recurrence during the blanking period after atrial fibrillation ablation

BACKGROUND

Early recurrences of atrial arrhythmias (ERAAs) after ablation may require therapeutic intervention. The optimal medical therapy that prevents ERAAs requires clarification. This study aimed to compare the incidence of ERAAs between patients who received or did not receive bisoprolol transdermal patches (BTPs) at 3 months postablation.

METHODS

This single-center retrospective study enrolled 203 consecutive patients with paroxysmal atrial fibrillation (AF) who had undergone their first ablation, comprising 59 in the BTP group and 144 in the non-BTP group. Follow-up assessments were conducted monthly for 3 months. We evaluated the incidence of ERAAs.

RESULTS

During the initial 1-week observational period, the rate of ERAAs was lower in the BTP group (5.0%) than that in the non-BTP group (18.8%) (P = .013). At 3 months postablation, the rate of ERAAs was lower in the BTP group (6.8%) than that in the non-BTP group (25.7%) (P = .002). The cumulative freedom from ERAAs was significantly lower in the BTP group than in the non-BTP group (log-rank: P = .003). Administering BTPs was an independent factor that protected against ERAAs (odds ratio 0.181, [95% confidence interval 0.059-0.559], P = .003).

CONCLUSION

BTPs may prevent ERAAs after ablation.

The effect of concomitant chronic kidney disease on the recurrence of atrial fibrillation after catheter ablation: A protocol for systematic review and meta-analysis

BACKGROUND

Some new trials have reported the effectiveness of chronic kidney disease on recurrence of atrial fibrillation following catheter ablation. Limited by small number of studies and insufficient outcomes, previous meta-analyses also failed to draw a consistent conclusion on this topic. We thus conducted a new meta-analysis to systematically analyze the effect of chronic kidney disease on recurrence of atrial fibrillation following catheter ablation.

METHODS

Two independent investigators followed The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting guidelines to conduct the present meta-analysis. From the inception to June 2021, the EMBASE, PubMed, Web of Science, and Cochrane Library electronic databases were searched using the key phrases "atrial fibrillation," "chronic kidney disease," "catheter ablation," "renal failure," "renal function," "renal insufficiency," "end-stage renal disease," and "dialysis" for all relevant English-language trials. Observational or randomized controlled trial focusing on assessing the effectiveness of chronic kidney disease on recurrence of atrial fibrillation following catheter ablation was included. P < .05 was set as the significance level.

RESULTS

Our hypothesis was that chronic kidney disease is associated with increased atrial fibrosis and a higher risk of arrhythmia recurrence and that restoration of normal rhythm through catheter ablation is associated with improved kidney function.

REGISTRATION NUMBER

10.17605/OSF.IO/3WJAE.

The Efficacy of Anti-inflammatory Agents in the Prevention of Atrial Fibrillation Recurrences

Several studies have indicated an association between inflammation and the recurrence of Atrial Fibrillation (AF), especially after ablation, which is a therapeutic option leading to local inflammation. On the other hand, each AF can lead to another AF, as a general rule. Thus, preventing recurrences of AF is extremely important for patient outcomes. In this paper, we attempted to review the effect of medicinal agents with anti-inflammatory properties on the prevention of AF recurrence. There are several randomized controlled trials (RCTs) and meta-analyses on the prevention of AF recurrence using agents with anti-inflammatory properties, which include steroids, colchicine, statins, and n-3 fatty acids (n-3 FA). Clinical trials evaluating the efficacy of anti-inflammatory drugs in preventing the recurrence of AF led to inconsistent results for corticosteroids, statins and n-3 FAs. These results may be related to the fact that inflammation is not the only factor responsible for triggering recurrences of AF. For example, the presence of structural, mechanical and electrical remodeling could potentially be the most important factors that trigger recurrences of AF but these factors have not been addressed in most of the reported studies. Therefore, future clinical trials are needed to compare the efficacy of anti-inflammatory drugs in AF patients with, or without other factors. For colchicine, a potent anti-inflammatory drug, there are limited studies. However, all the studies investigating colchicine in the context of AF were consistent and promising, especially when colchicine was used on a short-term basis following ablation in patients with paroxysmal AF. Therefore, colchicine could be a promising candidate for further clinical studies involving recurrent AF.

Atrial fibrillation type modulates the clinical predictive value of neutrophil-to-lymphocyte ratio for atrial fibrillation recurrence after catheter ablation

BACKGROUND

The neutrophil-to-lymphocyte ratio (NLR) has been proposed as an indicator of a systemic inflammatory response. There are baseline differences in the inflammation status between paroxysmal atrial fibrillation (PAF) and persistent AF (PerAF). The NLR changes and late recurrences of AF (LRAF) after ablation depending on the AF type remain unknown.

METHODS

Consecutive AF patients undergoing pulmonary vein isolation (PVI) by radiofrequency catheter ablation were enrolled from September 2014 to June 2018. The peripheral blood leukocyte NLR 1 day before and 36-48 h after PVI were measured. First, the relationship between NLR changes after to before ablation (ΔNLR) and ERAFs/LRAFs in PAF and PerAF patients were investigated to exclude the baseline inflammation status and evaluate catheter ablation induced inflammation. Second, the clinical impact of the NLR for predicting LRAFs was evaluated.

RESULTS

There hundred sixty-nine PAF and 264 PerAF patients from Osaka Rosai AF registry were enrolled. The ratio of ERAFs/LRAFs in PAF and PerAF patients were 26.8%/22.5% and 39.4%/29.9%, respectively. In PAF and PerAF patients, the ΔNLR was significantly higher with ERAF than no-ERAF (p = 0.022 and p = 0.010, respectively). In PAF patients, the ΔNLR was significantly higher with LRAF than no-LRAF (p = 0.017), while with PerAF, the ΔNLR did not significantly differ between LRAFs and no-LRAFs. In PAF, the ΔNLR was independently and significantly associated with LRAFs after PVI (p = 0.029).

CONCLUSION

The ΔNLR was significantly higher only in PAF patients with LRAFs than no-LRAFs, but not in PerAF patients. The ΔNLR was useful for predicting LRAFs after PVI in PAF patients.

C-reactive protein for prediction of atrial fibrillation recurrence after catheter ablation

BACKGROUND

Inflammation plays an important role in the initiation and progression of atrial fibrillation (AF), but data about the relationship between subclinical inflammation and recurrence of AF after catheter ablation remains poorly studied. We aimed to assess whether plasma levels of C-reactive protein (CRP) are associated with long-term AF recurrence following catheter ablation.

METHODS

Prior to the intervention, plasma CRP concentrations were measured in patients who underwent first catheter ablation for AF. AF recurrence was evaluated after 12 months and defined as any AF episode longer than 30 s recorded on either 12-lead electrocardiogram, 24-h Holter or 7-day Holter monitoring. Multivariable adjusted Cox models were constructed to examine the association of CRP levels and AF recurrence.

RESULTS

Of the 711 patients (mean age: 61 years, 25% women) included in this study, 247 patients (35%) experienced AF recurrence after ablation. Patients who were in the highest CRP quartile had a higher rate of recurrent AF compared to those who were in the lowest quartile (53.4 vs. 33.1% at 1 year of follow-up; P = 0.004). The adjusted hazard ratios (aHR) of recurrent AF across increasing quartiles of CRP were 1.0 (reference), 1.26 (95% confidence interval [CI], 0.86-1.84), 1.15 (95% CI, 0.78-1.70) and 1.60 (95% CI, 1.10-2.34) (P trend = 0.015). A similar effect was observed when CRP was analyzed as continuous variable (aHR per unit increase, 1.21; 95% CI, 1.05-1.39; P = 0.009). When a predefined CRP cut-off of 3 mg/l was applied, patients with CRP levels of 3 mg/l or above had a higher risk of AF recurrence than those with levels below (aHR, 1.44; 95% CI, 1.06-1.95; P = 0.019).

CONCLUSIONS

Increasing pre-interventional CRP levels are associated with a higher risk of AF recurrence in patients undergoing catheter ablation for AF.

TRAIL REGISTRATION

ClinicalTrials.gov identifier, NCT03718364.

Contemporary Surgical Management of Atrial Fibrillation

Atrial fibrillation is a common arrhythmia which may cause symptoms that significantly impact quality of life and is associated with increased risk of stroke, heart failure, and sudden death. Over the past three decades many surgical techniques as well as catheter-bases procedures have been developed to treat atrial fibrillation. In this review we describe the indications, treatments, outcomes, surgical techniques, and technical advances reported in the literature.

Recurrent Atrial Fibrillation After Radiofrequency Ablation: What to Expect

Recurrent atrial fibrillation after radiofrequency ablation is observed in up to 50% of patients within 3 months. Early and multiple recurrences predict late recurrences within 1 year, which occurs in 20% to 50% of patients. Although no consensus exists regarding patient selection and timing of redo ablation, we refer symptomatic patients with multiple recurrences and persistent atrial fibrillation for ablation. Reisolation of reconnected pulmonary veins and ablation of nonpulmonary vein triggers is the primary ablation strategy. In addition to repeat ablation, we recommend weight loss, treatment of sleep-disordered breathing, and management of comorbid conditions for durable maintenance of sinus rhythm.

Inflammatory and Infectious Processes Serve as Links between Atrial Fibrillation and Alzheimer's Disease

Atrial fibrillation (AF) is one of the most prevalent forms of arrhythmia that carries an increased risk of stroke which, in turn, is strongly associated with cognitive decline. The majority of dementia cases are caused by Alzheimer's disease (AD) with obscure pathogenesis. While the exact mechanisms are unknown, the role of inflammatory processes and infectious agents have recently been implicated in both AD and AF, suggesting a common link between these maladies. Here, we present the main shared pathways underlying arrhythmia and memory loss. The overlapping predictive biomarkers and emerging joint pharmacological approaches are also discussed.

Genetic Susceptibility for Atrial Fibrillation in Patients Undergoing Atrial Fibrillation Ablation

BACKGROUND

Ablation is a widely used therapy for atrial fibrillation (AF); however, arrhythmia recurrence and repeat procedures are common. Studies examining surrogate markers of genetic susceptibility to AF, such as family history and individual AF susceptibility alleles, suggest these may be associated with recurrence outcomes. Accordingly, the aim of this study was to test the association between AF genetic susceptibility and recurrence after ablation using a comprehensive polygenic risk score for AF.

METHODS

Ten centers from the AF Genetics Consortium identified patients who had undergone de novo AF ablation. AF genetic susceptibility was measured using a previously described polygenic risk score (N=929 single-nucleotide polymorphisms) and tested for an association with clinical characteristics and time-to-recurrence with a 3 month blanking period. Recurrence was defined as >30 seconds of AF, atrial flutter, or atrial tachycardia. Multivariable analysis adjusted for age, sex, height, body mass index, persistent AF, hypertension, coronary disease, left atrial size, left ventricular ejection fraction, and year of ablation.

RESULTS

Four thousand two hundred seventy-six patients were eligible for analysis of baseline characteristics and 3259 for recurrence outcomes. The overall arrhythmia recurrence rate between 3 and 12 months was 44% (1443/3259). Patients with higher AF genetic susceptibility were younger (P<0.001) and had fewer clinical risk factors for AF (P=0.001). Persistent AF (hazard ratio [HR], 1.39 [95% CI, 1.22-1.58]; P<0.001), left atrial size (per cm: HR, 1.32 [95% CI, 1.19-1.46]; P<0.001), and left ventricular ejection fraction (per 10%: HR, 0.88 [95% CI, 0.80-0.97]; P=0.008) were associated with increased risk of recurrence. In univariate analysis, higher AF genetic susceptibility trended towards a higher risk of recurrence (HR, 1.08 [95% CI, 0.99-1.18]; P=0.07), which became less significant in multivariable analysis (HR, 1.06 [95% CI, 0.98-1.15]; P=0.13).

CONCLUSIONS

Higher AF genetic susceptibility was associated with younger age and fewer clinical risk factors but not recurrence. Arrhythmia recurrence after AF ablation may represent a genetically different phenotype compared to AF susceptibility.

Comparing between second-generation cryoballoon vs open-irrigated radiofrequency ablation in elderly patients: Acute and long-term outcomes

Background

Limited comparative data are available regarding catheter ablation (CA) of atrial fibrillation (AF) using second‐generation cryoballoon (CB‐2) vs radiofrequency (RF) ablation in elderly patients (>75‐year‐old).

Hypothesis

CB‐2 ablation may demonstrate different outcomes compared with that using RF ablation for elderly patients with AF.

Method

Elderly patients with symptomatic drug‐refractory AF were included in the study. Pulmonary vein isolation was performed in all patients.

Results

A total of 324 elderly patients were included (RF: 176, CB‐2:148) from September 2016 to April 2019. The CB‐2 was associated with shorter procedure time and left atrial dwell time (112.9 ± 11.1 vs 135.1 ± 9.9 minutes, P < .001; 53.7 ± 8.9 vs 65.1.9 ± 9.0 minutes, P < .001), but marked fluoroscopy utilization (22.1 ± 3.3 vs 18.5 ± 3.6 minutes, P < .001). Complications occurred in 3.3% (CB‐2) and 6.2% (RF) of patients with no significant different (P = .307). The length of stay after ablation was shorter, but the costs were higher in the CB‐2 group (1.94 vs 2.53 days, P < .001 and 91 132.6 ± 3723.5 vs 81 149.4 ± 6824.1 CNY, P < .001) compared to the RF group. Additionally, the rate of early recurrence of atrial arrhythmia was lower in the CB‐2 group (14.2 vs 23.3%, P = .047), but the long‐term success rate was similar between two groups.

Conclusions

CB‐2 is associated with shorter procedure time, left atrial dwell time, and length of stay after ablation, but its costs and fluoroscopy time are greater than the RF group. Moreover, the rate of complications and long‐term success are similar between the two groups.

Laryngeal mask versus facemask in the respiratory management during catheter ablation

BACKGROUND

The purpose of this study is to investigate if a laryngeal mask could improve respiratory condition during radiofrequency catheter ablation (RFCA).

METHODS

Twenty-four consecutive patients who underwent RFCA for atrial fibrillation were divided into two groups (Facemask group; n = 10, Laryngeal mask group; n = 14). All patients were completely sedated under intravenous anesthesia and fitted with artificial respirators during the RFCA. The capnography waveforms and their differential coefficients were analyzed to evaluate the changes of end-tidal CO₂ (ETCO₂) values, respiratory intervals, expiratory durations, and inspiratory durations.

RESULTS

During the RFCA, ETCO₂ values of the laryngeal mask group were higher than those of the facemask group (36.0 vs. 29.2 mmHg, p = 0.005). The respiratory interval was significantly longer in the laryngeal mask group than those in the facemask group (4.28 s vs.5.25 s, p < 0.001). In both expiratory and inspiratory phases, the mean of the maximum and minimum values of CO₂ was significantly higher when using a laryngeal mask than when using a facemask. The inspiratory-expiratory ratio of the laryngeal mask group was significantly larger than that of the facemask group (1.59 vs. 1.27, p < 0.001). The total procedure duration, fluoroscopic duration and the ablation energy were significantly lower in the laryngeal mask group than in the facemask group. The ETCO₂ value is the most influential parameter on the fluoroscopic duration during the RFCA procedure (β = - 0.477, p = 0.029).

CONCLUSIONS

The use of a laryngeal mask could stabilize respiration during intravenous anesthesia, which could improve the efficiency of RFCA.

Costs and long-term outcomes following pulmonary vein isolation for atrial fibrillation in elderly patients using second-generation cryoballoon vs. open-irrigated radiofrequency in China

Purpose

Limited comparative data are available regarding catheter ablation (CA) of atrial fibrillation (AF) using second-generation cryoballoon (CB-2) vs. radiofrequency (RF) ablation in elderly patients (> 75 years old). The present study aimed to compare the costs and clinical outcomes in elderly patients using these two strategies.

Methods

Elderly patients with symptomatic drug-refractory paroxysmal/short-lasting persistent AF were included in the study. Pulmonary vein isolation (PVI) was performed in all patients.

Results

A total of 324 elderly patients were included (RF,176; CB-2,148) from September 2016 to April 2019. The CB-2 was associated with shorter procedure time and left atrial dwell time (112.9 ± 11.1 vs. 135.1 ± 9.9 min, P < 0.001; 53.7 ± 8.9 vs. 65.1.9 ± 9.0 min, P < 0.001) but marked fluoroscopy utilization (22.1 ± 3.3 vs. 18.5 ± 3.6 min, P < 0.001). Complications occurred in 3.3% (CB-2) and 6.2% (RF) of patients with no significant different (p = 0.307). The length of stay after ablation was shorter, but the costs were higher in the CB-2 group (1.94 vs. 2.53 days, P < 0.001 and 91,132.6 ± 3723.5 vs. 81,149.4 ± 6824.1 CNY, P < 0.001) compared to the RF group. Additionally, the rate of early recurrence of atrial arrhythmia (ERAA) was lower in the CB-2 group (14.2 vs. 23.3%, P = 0.047), but the long-term success rate was similar between two groups.

Conclusions

CB-2 is associated with shorter procedure time, left atrial dwell time, and length of stay after ablation, as well as lower ERAA, but its costs and fluoroscopy time are greater than the RF group. Moreover, the rate of complications and long-term success is similar between the two groups.

Simple hematological predictors of AF recurrence in patients undergoing atrial fibrillation ablation

Backgound

Red cell distribution width (RDW) and neutrophil-to-lymphocyte ratio (NLR) are simple hematologic indices that have been used to predict adverse outcomes in different clinical settings. The aim of our study is to determine whether RDW and NLR can predict atrial fibrillation (AF) recurrence in patients undergoing AF ablation.

Methods

Consecutive patients, without known hematological disorders, who underwent AF catheter ablation between January 2014 and April 2017 were enrolled into this study. Blood samples were taken one day before and five hours after the ablation procedure.

Results

A total of 346 patients (224 males (65%), mean age: 59 ± 11 years old) were included. After a mean follow up of 26.2 ± 12.1 months, 80 (23.1%) patients experienced late AF recurrence (defined as any recurrence after the blanking period of three months), while 97 (28%) patients experienced early AF recurrence during the blanking period. Univariate analysis showed that early arrhythmia recurrence, type of AF and NLR after the procedure were significantly associated with late AF recurrence, while early arrhythmia recurrence and NLR remained significant in multivariate analysis. RDW was not associated with late AF recurrence. None of the parameters above predicted early arrhythmia recurrence.

Conclusions

Simple and inexpensive hematological indices such as NLR should be evaluated for their ability to predict AF recurrence in patients undergoing catheter ablation in larger prospective studies.

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.

Catheter ablation of atrial fibrillation-A key role in heart failure therapy?

Atrial fibrillation (AF) and heart failure (HF) are epidemic cardiac diseases and are often detected in the same patient. Recent evidence suggests that this is not a mere coincidence but that the strategy of AF treatment may impact HF development. This review comprehensively summarizes current trial data on rhythm and rate control strategies in atrial fibrillation with a special focus on catheter ablation of AF in HF patients. For a long time, rate and rhythm control strategies for AF have been regarded as equal regarding long term mortality. Decision making has been based on the symptoms of patients. Current trials, however, show that the treatment strategy of AF and its effectiveness may significantly impact survival of HF patients. The benefits of rhythm control in HF patients may have been masked by side effects of antiarrhythmic drugs. If rhythm control, however, is achieved by catheter ablation, a reduction of HF related mortality can be observed. As catheter ablation of AF may reduce mortality in HF patients, AF ablation should be preferred over medical treatment in HF patients. In general, HF patients may profit most from rigorous AF treatment.

Effect of Postablation Statin Treatment on Arrhythmia Recurrence in Patients With Paroxysmal Atrial Fibrillation

BACKGROUND

Statins have been proposed as a means to prevent postablation atrial fibrillation (AF) recurrences, mainly on the basis of their pleiotropic effects. The objective of this subanalysis of a prospectively randomized controlled study population of patients undergoing radiofrequency ablation for paroxysmal AF was to test the hypothesis that statin treatment is associated with longer time to recurrence.

METHODS AND RESULTS

This is a subanalysis over an extended follow-up period of a prospective randomized study (ClinicalTrials.gov Identifier NCT01791699). Among 291 patients, 2 propensity score-matched subgroups of patients who received or did not receive statins after pulmonary vein isolation were created. In the unmatched cohort, there was no difference in the rate of recurrence between statin-treated and not treated patients, with a 1-year recurrence estimate of 19% and 23%, respectively (Gehan statistic 0.59, P = 0.443). In the propensity-matched cohort (N = 166, 83 per group), recurrence-free survival did not differ significantly between groups (839 days, 95% confidence interval 755-922 days, in the no statin group vs. 904 days, 95% confidence interval 826-983 in the statin group; P = 0.301). The 1-year recurrence rate estimate was 30% in the no statin group versus 27% in the statin group (Gehan statistic 0.56, P = 0.455).

CONCLUSION

Statin treatment does not seem to affect AF recurrence in following radiofrequency ablation for paroxysmal AF, over a follow-up time of about 2.5 years.

Steroids prevent early recurrence of atrial fibrillation following catheter ablation: a systematic review and meta-analysis

Previous studies have reported that steroids may reduce the risk of atrial fibrillation (AF) recurrence after catheter ablation, but data regarding this issue have been controversial. Therefore, we conducted a meta-analysis of randomized clinical trials (RCTs) and observational studies to ascertain the association of steroids and AF recurrence after ablation. PubMed, Embase, and Cochrane online databases were searched from inception to December 2017. The primary outcome of the meta-analysis was short-term or long-term AF recurrence following a single ablation procedure with or without the use of steroids. Both fixed- and random-effects models were used to calculate the overall effect estimates. Eight studies (four RCTs and four observational studies), with a total 992 patients, were included in the present study. Our meta-analysis shows that steroid use was associated with reduced AF occurrence at 3 months (odd ratio (OR) = 0.53, 95% confidence interval (CI) = 0.31–0.90, P=0.02) and 12–14 months (OR = 0.67, 95% CI = 0.47–0.95, P=0.02) after radiofrequency (RF) catheter ablation (RFCA). No clear benefit was observed for AF recurrence at 2–3 days, 1 or 24 months of follow-up. Steroid use was associated with decreased risk of early AF recurrence 3 and 12–14 months after ablation. No clear relationship was observed for 2–3 days, 1 and 24 months of follow-up and further data are needed to clarify these results.

Effect of corticosteroids on atrial fibrillation after catheter ablation: a meta-analysis. J Zhejiang Univ Sci B 2018;19:57-64. [PMID: 29308608 DOI: 10.1631/jzus.b1600529]

OBJECTIVE

The purpose of this meta-analysis was to explore the effect of corticosteroids on atrial fibrillation (AF) following catheter ablation.

METHODS

We searched PubMed, Embase, and the Cochrane Central Register of Controlled Trials for published articles describing the effect of corticosteroids in preventing AF recurrence after catheter ablation. Data on study and patient were extracted. Risk ratios (RRs) and 95% confidence intervals (CIs) were calculated by use of a random-effect model, and P values of <0.05 were considered significant.

RESULTS

Two randomized controlled trials (RCTs) and three cohort studies involving 846 patients were included in this meta-analysis. Within one month of catheter ablation, corticosteroid use was associated with a declined risk of recurrence of AF in RCT (RR 0.57, 95% CI 0.39 to 0.85, P=0.005), but without significant effect in cohort studies (RR 1.01, 95% CI 0.79 to 1.30, P=0.94). After three months of catheter ablation, corticosteroids did not have a significant effect in the prevention of late recurrence of AF in either RCT (RR 0.78, 95% CI 0.38 to 1.59, P=0.49) or cohort studies (RR 0.96, 95% CI 0.70 to 1.31, P=0.78).

CONCLUSIONS

Our meta-analysis suggested that periprocedural administration of corticosteroids of catheter ablation was associated with reduction of early but not late recurrence of AF.

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.

Early Recurrences During the Blanking Period after Atrial Fibrillation Ablation

Early recurrences of atrial arrhythmias (ERAA) after ablation are common and predict late recurrences and ablation failure.However,becausea proportion of patients with ERAA will have no subsequent arrhythmias after the blanking period, consensus guidelines recommend against immediate repeat ablation for ERAA episodes occurring during the first 3 months post-ablation. In this review, we summarize the predictors, significance, and treatment of ERAA after AF ablation.

Association of pre-ablation level of potential blood markers with atrial fibrillation recurrence after catheter ablation: a meta-analysis

Aims

The meta-analysis was aimed to search for candidate blood markers whose pre-ablation level was associated with atrial fibrillation (AF) recurrence after radiofrequency catheter ablation (RFCA).

Methods and results

A systematic literature search of PubMed, EMBASE, Springer Link, Web of Science, Wiley-Cochrane library, and supplemented with Google scholar search engine was performed. Thirty-six studies covering 11 blood markers were qualified for this meta-analysis. Compared with the nonrecurrence group, the recurrence group had increased pre-ablation level of atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), N-terminal pro-brain natriuretic peptide (NT-pro-BNP), interleukin-6 (IL-6), C-reactive protein, low density lipoprotein (LDL), and tissue inhibitor of metal loproteinase-2 (TIMP-2) [standardized mean difference (95% confidence interval): 0.37 (0.13-0.61), 0.77 (0.40-1.14), 1.25 (0.64-1.87), 0.37 (0.21-0.52), 0.35 (0.10-0.60), 0.24 (0.07-0.42), 0.17 (0.00-0.34), respectively], while no statistical difference of pre-ablation level of white blood cell, total cholesterol, triglyceride, and transforming growth factor-β1 was found. Subgroup analysis demonstrated that ANP was associated with AF recurrence in participants who had no concomitant structural heart diseases (SHD); however, not in participants who had SHD, C-reactive protein was associated with AF recurrence in Asian studies, whereas not in European studies.

Conclusion

Increased pre-ablation level of ANP, BNP, NT-pro-BNP, IL-6, C-reactive protein, LDL, and TIMP-2 was associated with greater risk of AF recurrence after RFCA.