Immediate and medium-term outcomes of cryoballoon-based pulmonary vein isolation in patients with paroxysmal and persistent atrial fibrillation: single-centre experience

Effects of Inflammatory Cell Death Caused by Catheter Ablation on Atrial Fibrillation

Atrial fibrillation (AF) poses a serious healthcare burden on society due to its high morbidity and the resulting serious complications such as thrombosis and heart failure. The principle of catheter ablation is to achieve electrical isolation by linear destruction of cardiac tissue, which makes AF a curable disease. Currently, catheter ablation does not have a high long-term success rate. The current academic consensus is that inflammation and fibrosis are central mechanisms in the progression of AF. However, artificially caused inflammatory cell death by catheter ablation may have a significant impact on structural and electrical remodeling, which may affect the long-term prognosis. This review first focused on the inflammatory response induced by apoptosis, necrosis, necroptosis, pyroptosis, ferroptosis and their interaction with arrhythmia. Then, we compared the differences in cell death induced by radiofrequency ablation, cryoballoon ablation and pulsed-field ablation. Finally, we discussed the structural and electrical remodeling caused by inflammation and the association between inflammation and the recurrence of AF after catheter ablation. Collectively, pulsed-field ablation will be a revolutionary innovation with faster, safer, better tissue selectivity and less inflammatory response induced by apoptosis-dominated cell death.

Harmful Impact of Tobacco Smoking and Alcohol Consumption on the Atrial Myocardium

Tobacco smoking and alcohol consumption are widespread exposures that are legal and socially accepted in many societies. Both have been widely recognized as important risk factors for diseases in all vital organ systems including cardiovascular diseases, and with clinical manifestations that are associated with atrial dysfunction, so-called atrial cardiomyopathy, especially atrial fibrillation and stroke. The pathogenesis of atrial cardiomyopathy, atrial fibrillation, and stroke in context with smoking and alcohol consumption is complex and multifactorial, involving pathophysiological mechanisms, environmental, and societal aspects. This narrative review summarizes the current literature regarding alterations in the atrial myocardium that is associated with smoking and alcohol.

Efficacy and Safety of Nepcell STM in Achieving Hemostasis After Removal of a 15-Fr Femoral Venous Sheath in Patients Undergoing Cryoballoon Ablation for Atrial Fibrillation

Background: Hemostasis at the femoral venous access site after cryoballoon ablation (CA) for atrial fibrillation (AF) is often prolonged because of aggressive anticoagulation and the use of 15-Fr-caliber sheaths. The Nepcell S^TM (NC) is a newly developed hemostatic pad made of fibrosed calcium alginate extracted from natural seaweed. The calcium ions from the NC accelerate the clotting cascade. This single-center randomized clinical trial assessed the efficacy and safety of the NC in patients undergoing CA for AF.

Methods and Results: In all, 62 patients undergoing CA for non-valvular paroxysmal AF were randomly assigned to either the NC or control group. The primary endpoints of this study were time to hemostasis, internal hemorrhage, and rebleeding. Secondary endpoints were the length of hospital stay (LOS) and vascular complications at 1 month. The time to hemostasis was significantly shorter in NC than control group (mean [±SD] 377±216 vs. 505±241 s; P=0.031). The frequency of internal hemorrhaging (6% vs. 37%; P=0.003) and rebleeding (0% vs. 13%; P=0.033) was lower in the NC than control group, contributing to a decreased LOS in the NC group (3.56±0.67 vs. 4.23±0.73 days; P<0.001). There were no NC-related vascular complications at the 1-month echographic examination.

Conclusions: The use of NC was associated with a shorter hemostasis time and fewer bleeding complications in patients undergoing CA for AF, leading to a shorter LOS.

Repeat procedures for recurrent persistent atrial fibrillation: A propensity-matched score comparison between left atrial linear ablation with radiofrequency and posterior wall isolation with the cryoballoon

AIMS

To evaluate the clinical outcome in patients undergoing repeat procedures for recurrent persistent atrial fibrillation following an index cryoballoon (CB-A) pulmonary vein isolation ablation on a mid-term follow-up of 12 months.

METHODS

In this propensity score-matched comparison, 50 patients undergoing left atrial posterior wall isolation (LAPWI) with the CB-A were matched to 50 patients treated with additional linear ablation using radiofrequency catheter ablation (RFCA).

RESULTS

Meantime to repeat the procedure was 9.74 ± 4.36 months. At 12 months follow-up freedom from atrial tachyarrhythmias (ATas) was achieved in 82% of patients in the LAPWI group and in 62% of patients in the linear ablation group (P = .03). Regression analysis demonstrated that relapses during the blanking period and LA dimensions were independent predictors of ATas recurrences following the repeat procedure.

CONCLUSION

LAPWI using CB-A is associated with a significantly higher freedom from atrial arrhythmias when compared with the RFCA mediated left atrial linear lesions on a mid-term follow-up of 12 months in patients with persAF undergoing a redo procedure.

Is there any Link Between Vitamin D and Recurrence of Atrial Fibrillation after Cardioversion?

Introduction

Atrial fibrillation (AF) is the most common chronic arrhythmia in the elderly population. In symptomatic patients, restoration and maintenance of sinus rhythm improve quality of life. Unfortunately, AF recurrence still occurs in a considerable number of patients after cardioversion (CV). In this study, we aimed to evaluate the association between vitamin D (VitD) and AF recurrence after electrical or medical CV.

Method

A total of 51 patients who underwent CV for symptomatic AF were included in the study. AF recurrence was defined as an AF pattern in 12-lead electrocardiography (ECG) recording after CV within 6 months or ECG Holter recording of AF lasting more than 30 seconds at 6-month follow-up.

Results

Mean vitD level was 21.4 ng/ml in our study population. VitD level was lower in the AF recurrence group than in the non-recurrence group (18 ng/ml vs. 26.3 ng/ml, respectively; P=0.001). Additionally, left atrial diameter was larger in the AF recurrence group compared to the non-recurrence group (4.4 vs. 4.1, P=0.025). Patients with AF recurrence were older than patients without AF recurrence, and, although the prevalence of hypertension is higher in the AF recurrence group, there was no statistically significant difference (P=0.107, P=0.867).

Conclusion

In our study, there is a strong association between vitD level and AF recurrence after CV. VitD deficiency might be a predictor of high risk of AF recurrence after CV and vitD supplementation during the follow-up might help the maintenance of sinus rhythm.

Left atrial structure and function predictors of recurrent fibrillation after catheter ablation: a systematic review and meta-analysis

BACKGROUND

Catheter ablation (CA) has become a conventional treatment for atrial fibrillation (AF), but remains with high recurrence rate. The aim of this meta-analysis was to determine left atrial (LA) structure and function indices that predict recurrence of AF.

METHODS

We systematically searched PubMed-Medline, EMBASE, Scopus, Google Scholar and the Cochrane Central Registry, up to September 2017 in order to select clinical trials and observational studies which reported echocardiographic predictors of AF recurrence after CA. Eighty-five articles with a total of 16 126 patients were finally included.

RESULTS

The pooled analysis showed that after a follow-up period of 21 ± 12 months, patients with AF recurrence had larger LA diameter with weighted mean difference (WMD: 2·99 ([95% CI 2·50-3·47], P<0·001), larger LA volume index (LAVI) maximal and LAVI minimal (P<0·0001 for both), larger LA area (P<0·0001), lower LA strain (P<0·0001) and lower LA total emptying fraction (LA EF) (P<0·0001) compared with those without AF recurrence. The most powerful LA predictors (in accuracy order) of AF recurrence were as follows: LA strain <19% (OR: 3·1[95% CI, -1.3-10·4], P<0·0001), followed by LA diameter ≥50 mm (OR: 2·75, [95% CI 1·66-4·56,] P<0·0001), and LAVmax >150 ml (OR: 2·25, [95% CI, 1.1-5·6], P = 0·0002).

CONCLUSIONS

Based on this meta-analysis results, a dilated left atrium with diameter more than 50 mm and volume above 150 ml or myocardial strain below 19% reflect an unstable LA that is unlikely to hold sinus rhythm after catheter ablation for atrial fibrillation.

Comparison of standard vs modified "figure-of-eight" suture to achieve femoral venous hemostasis after cryoballoon based atrial fibrillation ablation

BACKGROUND

Immediate hemostasis following removal of sheaths is essential to prevent access site complications after atrial fibrillation (AF) ablation. Despite various precautions to achieve complete hemostasis in a safe and effective manner, no standard approach is present yet.

OBJECTIVE

We aimed to compare the efficacy and safety of standard vs modified figure-of-eight (sFoE vs mFoE) suture for immediate venous hemostasis after cryoballoon (CB) AF ablation.

METHODS

A total of 150 patients who underwent CB catheter ablation were sequentially allocated to either sFoE (n = 75) or mFoE (n = 75) suture to achieve immediate venous hemostasis at right femoral access site after 15 Fr sheath removal. A "three-way stopcock" was used in the mFoE group rather than tying the knot as in a sFoE group. Demographics, clinical and procedural data, and access site complications were recorded.

RESULTS

Immediate haemostasis was achieved in all patients (n = 75) with mFoE suture as compared to 90.7% (n = 68) of sFoE suture group (P < .001). Light manual pressure of ≤1 min was required in five patients (6.7%) due to looseness and conventional manual compression because of the snapped silk suture during knotting was required in two patients (2.6%) in the sFoE group. Time to hemostasis was shorter in the mFoE group (P < .001), but time to ambulation and time to discharge were similar in both groups (P > .05). Although no minor or major access site complication has occurred in the mFoE group, in-hospital rebleeding (n = 2, 2.7%) and early local access site infection (n = 2, 2.7%) were observed in the sFoE group.

CONCLUSION

The mFoE suture using three-way stopcock is an available, effective, maybe safe, and time- and cost-saving alternative technique to achieve immediate hemostasis after removal of 15 Fr right femoral venous sheath in patients undergoing cryoablation.

Efficacy of temperature-guided cryoballoon ablation without using real-time recordings - 12-Month follow-up

Background

We sought to evaluate a temperature-guided approach of cryoballoon (CB) ablation without visualization of real-time recordings.

Methods and results

We analysed 166 patients (34.9% female, 60 ± 11 years) with paroxysmal or short-term persistent atrial fibrillation (AF). Comorbidities included diabetes mellitus (n = 28), coronary artery disease (n = 24), hypertension (n = 122), previous stroke or TIA > 3 months (n = 12). Cryoablation of the pulmonary veins (PV) was performed using first-generation (n = 78) and second-generation CB (n = 88). Two 5-minute freezes were performed for the first-generation and two 4-minute freezes for the second-generation CB with the intention to achieve a temperature drop below −40 °C. At 12-month follow-up, we observed overall freedom from AF in 92 patients (56.6%, mean time to AF recurrence 3.4 ± 2.9 months). There was a significant difference in freedom from AF between first-generation CB (45%) and second-generation CB (67%; p < 0.005). Complications were groin hematoma (4.8%) and phrenic nerve palsy (PVP) (2.4%). PVP disappeared after 12 months in all patients. Three patients developed cardiac tamponade (1.8%) that resolved without further sequelae after pericardiocentesis. Multivariate analysis revealed that only the achieved temperature in the right inferior PV (RIPV) was a predictor of long-term freedom from AF (OR 0.9; p = 0.014). Female gender was a predictor of AF recurrence (OR 6.1; p = 0.022).

Conclusion

Temperature-guided CB ablation without real-time recordings is feasible and safe without reducing the efficacy if second-generation CB is used. Deep nadir temperatures especially in the RIPV are necessary for long term-success.

Predictors of the paroxysmal atrial fibrillation recurrence following cryoballoon-based pulmonary vein isolation: Assessment of left atrial volume, left atrial volume index, galectin-3 level and neutrophil-to-lymphocyte ratio

Background

Cryoballoon-based pulmonary vein isolation (PVI) is a treatment option for atrial fibrillation (AF). Left atrial volume (LAV) and left atrial volume index (LAVi) are important parameters for long term success of PVI. Galectin-3 (Gal-3) and neutrophil to lymphocyte ratio (N/L ratio) are biomarkers to demonstrate the cardiac fibrosis and remodelling.

Methods

50 patients with symptomatic PAF despite ≥1 antiarrhythmic drug(s), who underwent PVI were enrolled. LAV, LAVi, Gal-3 and N/L ratio were calculated before ablation and after ablation at 6 and 12 months. According to AF recurrence patients were divided into two groups, recurrent AF (n = 14) and non-recurrent AF (n = 36).

Results

In both groups (recurrent and non-recurrent), initial and 12 months follow-up LAV values were 41.39 ± 18.13 ml and 53.24 ± 22.11 ml vs 48.85 ± 12.89 ml and 42.08 ± 13.85 (p = 0.037). LAVi were 20.9 ± 8.91 ml/m2 and 26.85 ± 11.28 ml/m2 vs 25.36 ± 6.21 and 21.87 ± 6.66 (p = 0.05) for recurrent and non-recurrent AF groups, respectively. In both groups PVI had no significant effect on serum Gal-3 levels and N/L ratio during 12 months follow-up. The comparison between two groups at the end of 12th month showed Gal-3 values of 6.66 ± 4.09 ng/ml and 6.02 ± 2.95 ng/ml (p = 0.516), N/L ratio values of 2.28 ± 1.07 10³/μl and 1.98 ± 0.66 10³/μl (p = 0.674).

Conclusion

LAV and LAVi are useful to predict the remodelling of the left atrium and AF recurrence after cryoballoon-based PVI. However, biomarkers such as Gal-3 and N/L ratio are not associated with AF recurrence.

Impact of the third generation cryoballoon on atrial fibrillation ablation: An useful tool?

BACKGROUND

Third-generation cryoballoon (CB3) is characterized by a 40% shorter distal tip designed to increase the rate of pulmonary veins real-time signal recording in order to measure time necessary to isolate veins, the "Time to effect" (TTE). Few data are currently available on clinical follow up of CB3 treated patients.

METHODS

Sixtyeight consecutive patients (mean age 57.8 ± 9.6 years, 48 male) with paroxysmal or persistent atrial fibrillation (AF) were enrolled. Thirthyfour (25 paroxysmal AF) underwent to a 28 mmCB3 pulmonary veins isolation and were compared to 34 treated (21 paroxysmal AF) with 28 mmCB2.

RESULTS

CB3 use was correlated to significant increase of the possibility to measure TTE in every treated veins (left superior 82,35% vs 23,53%, left inferior 70,59% vs 38,24%, right superior 58,82% vs 14,71%, right inferior 52,94% vs 17,65%). When it is measured, TTE wasn't different between two groups. Higher nadir temperature was observed in CB3 patients (-39.4 ± 5.2 °C vs -43.0 ± 7.2 °C, p = 0.03). CB3 procedures were shorter (91.4 ± 21.7 vs 110.9 ± 31.8 min, p = 0.018), with a significant reduction in cryoenergy delivery time (24.2 ± 8.5 vs 20.3 ± 6.7 min, p < 0.05), and a significant reduction in left atrium dwell time (59.3 ± 9.8 vs 69.3 ± 10.8 min, p = 0.02, p < 0.05). At one year follow up period the Kaplan-Meier curve didn't show any significant difference in AF-free survival (Log p = 0,49).

CONCLUSIONS

Novel CB3 is a useful tool in order to simplify AF cryoballoon ablation when compared to second generation cryoballoon, as observed in our experience. Follow up data seem confirm a clinical CB3 efficacy at least comparable CB2.

Atrial fibrillation ablation using cryoballoon technology: Recent advances and practical techniques

Atrial fibrillation (AF) affects 1-2% of the population, and its prevalence is estimated to double in the next 50 years as the population ages. AF results in impaired patients' life quality, deteriorated cardiac function, and even increased mortality. Antiarrhythmic drugs frequently fail to restore sinus rhythm. Catheter ablation is a valuable treatment approach for AF, even as a first-line therapy strategy in selected patients. Effective electrical pulmonary vein isolation (PVI) is the cornerstone of all AF ablation strategies. Use of radiofrequency (RF) catheter in combination of a three-dimensional electroanatomical mapping system is the most established ablation approach. However, catheter ablation of AF is challenging even sometimes for experienced operators. To facilitate catheter ablation of AF without compromising the durability of the pulmonary vein isolation, "single shot" ablation devices have been developed; of them, cryoballoon ablation, is by far the most widely investigated. In this report, we review the current knowledge of AF and discuss the recent evidence in catheter ablation of AF, particularly cryoballoon ablation. Moreover, we review relevant data from the literature as well as our own experience and summarize the key procedural practical techniques in PVI using cryoballoon technology, aiming to shorten the learning curve of the ablation technique and to contribute further to reduction of the disease burden.

Safety and efficacy of persistent atrial fibrillation ablation using the second-generation cryoballoon

BACKGROUND

The second-generation cryoballoon (CB) is increasingly used for treatment of persistent atrial fibrillation (AF). Data regarding the clinical outcome and mechanism of arrhythmia recurrence following persistent AF ablation using CB is sparse. In this study, we aimed to assess the efficacy of CB and mechanisms of atrial tachyarrhythmia (ATA) recurrence in patients with persistent AF.

METHODS AND RESULTS

A total of 133 patients (66 ± 10 years, 60% male) with symptomatic persistent AF, who were scheduled for PVI using the second-generation CB were enrolled. Follow-up included 24 h Holter recording at 3, 6 and 12 months. Any documented episode of ATA lasting more than 30 s was considered as a recurrent arrhythmic event. All targeted veins were isolated (100%). Phrenic nerve palsy with recovery during follow-up occurred in six patients (4.5%), no patient experienced tamponade or a cerebrovascular event. During 12.6 ± 5.4 months of follow-up, 89/133 (67%) patients were free of ATA recurrences. Multivariable analysis revealed recurrence in the blanking period (HR 11.46, 0.95 CI 3.92-33.49, p < 0.001), presence of cardiomyopathy (HR 2.75, 0.95 CI 1.09-6.96, p = 0.032) and PV abnormality (HR 3.56, 0.95 CI 1.21-10.43, p = 0.021) as predictors for late recurrence.

CONCLUSION

In patients with persistent AF, second-generation cryoballoon use is associated with an excellent safety profile and favorable outcomes. Arrhythmia recurrence during the blanking period, presence of cardiomyopathy and PV abnormality were independent predictors of long-term AF recurrence.

Practical Techniques in Cryoballoon Ablation: How to Isolate Inferior Pulmonary Veins

Catheter ablation is the most effective treatment option for patients suffering from symptomatic atrial fibrillation. Electrical isolation of the pulmonary veins is the procedural cornerstone. Point-by-point radiofrequency current energy ablation in combination with a 3D electro-anatomical mapping system is the established approach to ablation. In contrast, cryoballoon ablation uses a single-shot approach to facilitate pulmonary vein isolation. However, fixed cryoballoon diameters (28 mm or 23 mm) and non-balloon compliance can lead to technical difficulties in isolating variable pulmonary vein anatomies. This review focuses on key procedural aspects and illustrates practical techniques in cryoballoon pulmonary vein isolation to shorten the learning curve without compromising safety and efficacy. It has a special emphasis on inferior pulmonary veins.

The Impact of Advances in Atrial Fibrillation Ablation Devices on the Incidence and Prevention of Complications

The number of patients with atrial fibrillation currently referred for catheter ablation is increasing. However, the number of trained operators and the capacity of many electrophysiology labs are limited. Accordingly, a steeper learning curve and technical advances for efficient and safe ablation are desirable. During the last decades several catheter-based ablation devices have been developed and adapted to improve not only lesion durability, but also safety profiles, to shorten procedure time and to reduce radiation exposure. The goal of this review is to summarise the reported incidence of complications, considering device-related specific aspects for point-by-point, multi-electrode and balloon-based devices for pulmonary vein isolation. Recent technical and procedural developments aimed at reducing procedural risks and complications rates will be reviewed. In addition, the impact of technical advances on procedural outcome, procedural length and radiation exposure will be discussed.

Cryoballoon ablation in atrial fibrillation: Advantages and drawbacks

Pulmonary vein isolation is the cornerstone of atrial fibrillation ablation and is effective for preventing arrhythmias recurrences, especially in patients with paroxysmal atrial fibrillation. During the last years, cryoballoon ablation has emerged as an unquestionable alternative approach to radiofrequency ablation. Many non-randomized and randomized trials have proven undoubtedly that cryoballoon ablation displays similar efficacy and overall safety profile, when compared to radiofrequency ablation for the treatment of patients with drug-refractory paroxysmal atrial fibrillation. These results have been obtained in all types of pulmonary veins anatomical subsets, which confirms that there is no need to select patients according to the latter. The value of cryoablation in the setting of short persistent atrial fibrillation still needs more evidence. Importantly, cryoballoon ablation seems to be less operator-dependent and more reproducible than radiofrequency for the isolation of pulmonary veins.

Relationship between vitamin D level and left atrial fibrosis in patients with lone paroxysmal atrial fibrillation undergoing cryoballoon-based catheter ablation

BACKGROUND

Left atrial (LA) fibrosis is known as the hallmark for arrhythmogenic substrate in atrial fibrillation (AF). Quantification of LA fibrosis by using delayed-enhanced magnetic resonance imaging (DE-MRI) in AF patients is a pioneering noninvasive technique. Vitamin D (vitD) negatively regulates the renin-angiotensin system, binds to vitD receptors on cardiac myocytes, and has antioxidant properties that may ameliorate the inflammation and proarrhythmic substrate formation. However, its role in LA fibrosis is unclear. We aimed to investigate the association of serum 25(OH)D level with the extent of LA fibrosis by using DE-MRI and also predictors for AF recurrence after cryoablation was assessed in patients with paroxysmal AF.

METHODS

A total of 48 patients with lone paroxysmal AF (41.7% female; age: 48.5±8.4 years) who underwent DE-MRI at 1.5T and initial cryoballoon-based catheter ablation along with 48 healthy control subjects were enrolled. Fibrosis degree was categorized according to Utah class defined in the DECAAF study.

RESULTS

Serum 25(OH)D levels were significantly lower in AF group compared to control group (25.8±7.6ng/ml vs. 31.0±9.5ng/ml, p=0.004). Serum 25(OH)D levels were associated with moderate-severe LA fibrosis independent of other measures (OR: 0.72, 95% CI: 0.54-0.97, p=0.028). At a mean 16.5±2.6 months follow-up, late recurrence was observed in 10 (20.8%) patients. In multivariable Cox regression analysis, LA volume index (HR: 1.42, 95% CI: 1.01-2.01, p=0.045) and the extent of LA fibrosis (HR: 1.14, 95% CI: 1.01-1.28, p=0.034) were found as independently associated with late AF recurrence during follow-up.

CONCLUSION

Lower levels of serum 25(OH)D are significantly associated with more extensive LA fibrosis in patients with lone paroxysmal AF and may be implicated in the pathophysiology of AF recurrence after cryoablation. Further large-scale studies are needed to elucidate the exact role of vitD deficiency and replacement on LA fibrosis.

Results from a multicentre comparison of cryoballoon vs. radiofrequency ablation for paroxysmal atrial fibrillation: is cryoablation more reproducible?

AIM

Cryoballoon ablation (Cryoballoon) has emerged as a new alternative for the treatment of symptomatic drug-refractory atrial fibrillation (AF). Whether the results of Cryoballoon are more reproducible than those of radiofrequency (RF) ablation remains to be proved.

METHODS AND RESULTS

A total of 860 consecutive patients undergoing a first ablation procedure for paroxysmal AF (467 treated with RF and 393 treated with Cryoballoon) were selected from a prospective multicentre survey of AF ablation (FrenchAF). Radiofrequency and Cryoballoon were compared regarding mid-term efficacy and safety. During a median follow-up of 14 months (interquartile range 8-23), patients treated with Cryoballoon displayed similar rates of freedom from atrial arrhythmia relapse in centres performing this technique (68-80% at 18 months). However, in centres performing RF, a greater heterogeneity in procedural results was observed (46-79% were free from atrial arrhythmia relapse at 18 months). On multivariate analysis, Cryoballoon (HR = 0.47, 95% CI 0.35-0.65, P < 0.001) and annual AF ablation caseload (HR = 0.87 per every 100 AF ablation procedures per year; 95% CI 0.80-0.96, P = 0.003) were independent predictors of procedural success. However, on sensitivity analysis, according to the ablation method, annual AF ablation caseload predicted only sinus rhythm maintenance in the subgroup of patients treated with RF. Analysis of interoperator results with Cryoballoon and RF confirmed lower reproducibility of RF, but suggested that besides caseload, other operator-related factors may play a role.

CONCLUSION

Cryoballoon seems to be less operator-dependent and more reproducible than RF in the setting of paroxysmal AF ablation.

Efficacy of Short-Term Antiarrhythmic Drugs Use after Catheter Ablation of Atrial Fibrillation-A Systematic Review with Meta-Analyses and Trial Sequential Analyses of Randomized Controlled Trials

Background

The efficacy of short-term antiarrhythmic drugs (AADs) use compared with no-AADs prescription after catheter ablation of atrial fibrillation (AF) in preventing atrial arrhythmia recurrence is uncertain.

Methods

We searched PubMed, Embase, and the Cochrane Library through December 2015 to identify randomized controlled trials (RCTs) which evaluated the efficacy of short-term AADs use compared with no-AADs prescription after AF ablation in preventing atrial arrhythmia recurrence. The primary outcome was labeled as early atrial arrhythmia recurrence within 3 months after ablation. Secondary outcome was defined as late recurrence after 3 months of ablation. Random-effects model or fixed-effects model was used to estimate relative risks (RRs) with 95% confidence intervals (CIs).

Results

Six RCTs with 2,667 patients were included into this meta-analysis. Compared with no-AADs administration after AF ablation, short-term AADs use was associated with significant reduction of early atrial arrhythmia recurrence (RR, 0.68; 95% CI, 0.52–0.87; p = 0.003). Trial sequential analysis (TSA) showed that the cumulative Z-curve crossed the trial sequential monitoring boundary for benefit, establishing sufficient and conclusive evidence. However, compared with no-AADs prescription, short-term AADs use after AF ablation didn’t significantly reduce the risk of late atrial arrhythmia recurrence (RR, 0.92; 95% CI, 0.83–1.03; p = 0.15). TSA supported this result; meanwhile the estimated required information size (1,486 patients) was also met.

Conclusion

Short-term use of AADs after AF ablation can significantly decrease the risk of early atrial arrhythmia recurrence but not lead to corresponding reduction in risk of late atrial arrhythmia recurrence.

Characterization of Electrical Reconnection Following Pulmonary Vein Isolation Using First- and Second-Generation Cryoballoon

BACKGROUND

Second-generation cryoballoon (CB-2) is associated with improved outcomes for pulmonary vein isolation (PVI) compared to first generation (CB-1). However, data regarding the predictors of pulmonary vein (PV) electrical reconnection are limited. In this study, we aimed to characterize the predilection sites and predictors of reconnection in patients with recurrent atrial tachyarrhythmia (ATa) after PVI using CB-1 and CB-2.

METHODS

A total of 59 patients (mean age: 62 ± 11 years and 66% male) with recurrent ATa after previous CB-PVI, using either a 28-mm CB-1 or CB-2, underwent repeat ablation. PV reisolation was performed by irrigated radiofrequency ablation using three-dimensional electroanatomical mapping systems.

RESULTS

Electrical PV reconnection was detected in 10 of 11 (91%) of CB-1 patients compared to 41 of 48 (85%) of CB-2 patients. Time to redo procedure after index CB-1 was 8.9 ± 10.2 months and 11.2 ± 7.0 months in CB-2. Bonus freeze was applied in all patients with CB-1 and 41% of the patients with CB-2. Superior quadrants of both superior PVs and inferior quadrants of the both inferior PVs exhibited higher predilection for conduction compared to other quadrants (P < 0.001). Multivariate binary logistic analysis revealed that right inferior PV (RIPV; odds ratio [OR]: 1.52, 95% confidence interval [CI]: 1.09-2.13, P = 0.014) and minimum temperature (OR: 1.09, 95% CI: 1.03-1.15, P = 0.004) were the independent predictors of electrical reconnection after CB-2 ablation.

CONCLUSION

Conduction gaps after CB-1 and CB-2 were higher in inferior PVs compared to superior PVs. The RIPV and minimum CB temperature were independent predictors of PV electrical reconnection after CB-2.

Outcomes Of Cryoballoon Ablation Of Atrial Fibrillation: A Comprehensive Review

Over the last decade, cryoballoon ablation has emerged as an effective alternate strategy to point-by-point radiofrequency ablation for treatment of symptomatic atrial fibrillation. There are several reasons for this. First, the acute and long-term safety and efficacy associated with cryoablation appear comparable to that of radiofrequency ablation in patients with both paroxysmal and also persistent atrial fibrillation. Second, cryoablation offers certain advantages over conventional radiofrequency ablation including a gentler learning curve, shorter ablation and procedure times as well as lack of need for costly electroanatomical mapping technologies commonly utilized with radiofrequency ablation. Lastly, with the recent advent of the second-generation cryoballoon, the effectiveness of cryoablation has further improved dramatically. This comprehensive review examines the gradual evolution of the cryoablation tools as well as the rationale and data in support of the currently-available cryoballoon technologies for catheter ablation of atrial fibrillation.

Effect of Pulmonary Vein Anatomy and Pulmonary Vein Diameters on Outcome of Cryoballoon Catheter Ablation for Atrial Fibrillation

BACKGROUND

In this study, we aimed to determine pulmonary vein (PV) variation patterns in patients undergoing cryoballoon ablation for atrial fibrillation (AF) and their impacts on procedural success and recurrence and also to identify predictors for recurrence.

METHODS

We enrolled 54 patients with AF and having symptoms despite medical therapy. Prior to the procedure, PV variation and left atrium (LA) size were evaluated in all patients by computed tomography scan. Ablation procedure was performed with single balloon and predictors for AF recurrence were determined.

RESULTS

The study population consisted of 54 patients (male: 50 [27%], mean age: 53 ± 12) with AF. Paroxysmal AF and persistent AF were detected in 55.6% (30) and 44.4% (24) of the patients, respectively. Mean procedural and fluoroscopy times were 73 ± 19 minutes and 16 ± 4 minutes, respectively. The number of the patients with PV variation of right pulmonary vein (RPV) with >2 ostia and accessory PV was 27.8% (15) and 18.5% (10). During the follow-up, 20.4% (11) of patients had AF recurrence. Patients with recurrence had greater transverse LA size (62 ± 6 mm vs 57 ± 5 mm, P: 0014), longitudinal LA size (65 ± 5 mm vs 61 ± 6 mm, P: 0025), LA volume (78 ± 17 mL vs 65 ± 14 mL, P: 0011), fluoroscopy time (20.4 ± 4.6 minutes vs 15.7 ± 3.5 minutes, P: 0001), RPV with >2 ostia (72.7% vs 27.3%, P: 0001), right upper pulmonary vein (RUPV) diameter (21.6 ± 2.8 cm vs 15.8 ± 2.1 cm; P < 0001), and persistent AF (33.3% vs 66.7%, P: 0046). In multivariate analysis, RUPV diameter (β: 1006; P: 0010; odds ratio [OR]: 2736; 95% confidence interval [CI]: [1267-5906]) and fluoroscopy time (β: 0327; P: 0050; OR: 1386; 95% CI: [1000-1921]) were determined as independent predictors for AF recurrence.

CONCLUSIONS

Transverse and longitudinal LA size, LA volume, fluoroscopy time, presence of persistent AF, RUPV size, and the number of RPV ostia are associated with AF recurrence following cryoballoon-based ablation. RUPV size and fluoroscopy time are predictors for recurrence.

Circumferential pulmonary vein isolation as index procedure for persistent atrial fibrillation: a comparison between radiofrequency catheter ablation and second-generation cryoballoon ablation

AIMS

To assess the 1 year efficacy of pulmonary vein isolation (PVI) as index procedure for persistent atrial fibrillation (PersAF) comparing conventional radiofrequency irrigated-tip catheter ablation (RFCA) using contact-force technology and ablation using the second-generation cryoballoon (CB-AdvA).

METHODS AND RESULTS

One hundred consecutive patients (74 male, 74%; mean age 62.4 ± 9.6 years) with drug-refractory PersAF undergoing PVI using RFCA and CB-AdvA were enrolled. Follow-up was based on outpatient clinic visits including Holter-electrocardiograms. Recurrence of atrial tachyarrhythmias (ATas) was defined as a symptomatic or documented episode >30 s. Among 100 patients, 50 underwent RFCA whereas 50 CB-AdvA. Mean procedure and fluoroscopy times were 90.5 ± 41.7 vs. 140.2 ± 46.9 min and 14.5 ± 6.6 vs. 19.8 ± 6.8 min in the CB-Adv and in the RFCA group, respectively (P < 0.01). At 1 year follow-up, after a 3 months blanking period (BP), freedom from ATas off-drugs after a single procedure was 60% (28/50 patients) in the CB-Adv and 56% (27/50 patients) in the RFCA group (P = 0.71). Multivariate analysis demonstrated that PersAF duration (P = 0.01) and relapses during BP (P = 0.02) were independent predictors of ATa recurrences following the index procedure.

CONCLUSION

Freedom from ATas following PersAF ablation with RFCA and CB-Adv is comparable at 1 year follow-up after a single procedure. Ablation with the CB-Adv is associated with shorter procedure time and radiation exposure as compared with RFCA. Atrial tachyarrhythmias occurrence during BP and longer time of PersAF seem to be significant predictors of arrhythmia recurrences after the index procedure.

Red blood cell distribution width predicts outcome of cryoballoon-based atrial fibrillation ablation

PURPOSE

Elevated red blood cell distribution width (RDW) has been associated with atrial fibrillation (AF) in cross-sectional and prospective studies. In this study, we aim to evaluate the relation of preablation RDW levels to late AF recurrence following cryoablation.

METHODS

A total of 299 patients with symptomatic paroxysmal or persistent AF despite ≥ 1 antiarrhythmic drug(s) who were scheduled for cryoballoon-based AF ablation were enrolled in this prospective study.

RESULTS

A total of 299 patients (55.40 ± 10.60 years, 49.20 % male) were involved and followed up at a median time of 24 (6-44) months. Patients with late AF recurrence had higher RDW levels (14.30 ± 0.93 vs. 13.52 ± 0.93 %, p < 0.001). Multivariate Cox proportional hazard regression analysis showed that RDW level was an independent predictor for late AF recurrence (HR 1.88, 95 % CI 1.41-2.50, p < 0.001) along with left atrial (LA) diameter (HR 3.09, 95 % CI 1.81-5.27, p < 0.001), duration of AF (HR 1.04, 95 % CI 1.01-1.07, p = 0.02), and early AF recurrence (HR 6.39, 95 % CI 3.41-11.97, p < 0.001). A cut-off level of 13.75 % for RDW predicted late AF recurrence following cryoballoon-based pulmonary vein isolation (PVI) with a sensitivity and specificity of 78.00 and 70.00 %, respectively.

CONCLUSION

These findings suggest that elevated RDW may be a predictor of late recurrence following cryoballoon-based AF ablation. Further studies are needed to establish its exact pathophysiologic and prognostic roles.

The Optimal Treatment For Atrial Fibrillation In Less Developed Countries

Atrial fibrillation (AF) is the most common arrhythmia and is a major cardiovascular challenge due to its close association with increased morbidity and mortality. Although the incidence and prevalence of AF is slightly lower in developing countries than in developed countries, the AF-associated risk of stroke is similar. Treatment of AF is far from satisfactory in developing countries, which may be due to limited health-care resources and social and racial characteristics that differ from Western populations. Chronic rate control is still the main treatment strategy of persistent AF because anti-arrhythmic drugs have only a modest long-term effect on maintenance of sinus rhythm, and no superior impact in terms of cardiovascular outcomes. With the development of ablation techniques and strategies, more AF patients received catheter ablation, although the benefit, complications, and high recurrence rate associated with AF ablation remain under investigation. Improvement in antithrombotic therapy of AF has been observed, although still fewer patients receive oral anticoagulants in developing countries than in Western countries. Novel treatment for the prevention of thromboembolism, such as new oral anticoagulants with different mechanisms of action or the percutaneous transcatheter closure of the left atrial appendage, has recently been introduced in developing countries as an alternative option for the prevention of AF-associated strokes. More data are needed regarding upstream therapy.

Pulmonary vein isolation as index procedure for persistent atrial fibrillation: One-year clinical outcome after ablation using the second-generation cryoballoon

BACKGROUND

No data are available about the clinical outcome of pulmonary vein isolation (PVI) as an index procedure for persistent atrial fibrillation (PersAF) ablation using the second-generation cryoballoon (CB-Adv).

OBJECTIVE

The purpose of this study was to assess the 1-year efficacy of PVI as an index procedure for PersAF ablation using the novel CB-Adv.

METHODS

Sixty-three consecutive patients (45 male [71.4%], mean age 62.7 ± 9.7 years) with drug-refractory PersAF undergoing PVI using the novel CB-Adv were enrolled. Follow-up was based on outpatient clinic visits including Holter ECGs. Recurrence of atrial tachyarrhythmias (ATas) was defined as a symptomatic or documented episode >30 seconds.

RESULTS

A total of 247 PVs were identified and successfully isolated with a mean of 1.7 ± 0.4 freezes. Mean procedural and fluoroscopy times were 87.1 ± 38.2 minutes and 14.9 ± 6.1 minutes, respectively. Among 26 of 63 patients (41.3%) presenting with AF at the beginning of the procedure, 7 of 26 (26.9%) converted to sinus rhythm during ablation. Phrenic nerve palsy occurred in 4 of 63 patients (6.3%). At 1-year follow-up, after a 3-month blanking period (BP), 38 of 63 patients (60.3%) were in sinus rhythm. Because of ATa recurrences, 9 patients underwent a second procedure with radiofrequency ablation showing a pulmonary vein reconnection in 4 right-sided PVs (44.4%) and 3 left-sided PVs (33.3%). Multivariate analysis demonstrated that PersAF duration (P = .01) and relapses during BP (P = .04) were independent predictors of AT recurrences.

CONCLUSION

At 1-year follow-up, freedom from ATas following PersAF ablation with the novel CB-Adv is 60%. Phrenic nerve palsy is the most common complication. PersAF duration and relapses during the BP appear to be significant predictors of arrhythmic recurrences.