Long-term clinical outcomes after single freeze cryoballoon ablation for paroxysmal atrial fibrillation: a 5-year follow-up

Treatment of atrial fibrillation with second-generation cryoballoon followed by contact-sensing radiofrequency catheter ablation for arrhythmia recurrences-results of a 5-year follow-up

INTRODUCTION

The aim of this study was to report the long-term follow-up results of cryoballoon (CB) ablation in patients with atrial fibrillation.

METHODS

All consecutive patients who underwent second-generation CB ablation from February 2015 to December 2017 were included in our study. In all procedures, we used a 28-mm CB placed via a single transseptal puncture guided by intracardiac ultrasound. A 20-mm octapolar intraluminal circular catheter was used for intracardiac recordings. A single 180-s freeze strategy was employed. Repeated procedures were performed with a 3D mapping system and radiofrequency catheters.

RESULTS

A total of 126 patients (69.8% male, mean age 57 ± 11 years), of which 77.0% had paroxysmal atrial fibrillation (PAF), were included in the study. After a 5-year period, 52.4% of patients were in sinus rhythm without AF recurrence, off antiarrhythmic drugs. A total of 61.9% of patients were free of AF recurrence when redo PVI procedures were performed. When accounting for redo pulmonary vein isolation and antiarrhythmic drugs, a total of 73.8% of the patients were without AF recurrence in long-term follow-up. The patients who underwent redo pulmonary vein isolation procedures had statistically significant lower rates of AF recurrence (p = 0.006). In patients with PAF, long-term success rates improved from 62.9 to 79.4% for patients who underwent the redo procedure (p = 0.020). In patients with persistent atrial fibrillation (PersAF), success rates went up from 41.4 to 55.1% for patients with single or repeated PVI procedure (p = 0.071). In the whole cohort, a total of 3 (2.4%) procedure-related major complications occurred which included persistent PNP, arterial pseudoaneurysm, and arteriovenous fistula.

CONCLUSION

Our data suggest a favorable long-term safety and efficacy profile of second-generation CB ablation. In the mixed paroxysmal and persistent population, up to 73.8% of patients remained free of AF recurrence in the 5-year follow-up, when accounting for redo procedures and AADs. Only 2.4% of patients experienced major complications of the ablation procedure, none with permanent sequelae.

Comparison between cryoballoon double stop and single stop in patients with paroxysmal atrial fibrillation

BACKGROUND

Currently, cryoballoon (CB) thawing after single stop is generally performed. Previous research had reported that long thawing time using a single stop affects pulmonary veins tissue injury. However, it is uncertain whether CB thawing after single stop affects clinical outcomes.

OBJECTIVE

This study aimed to clarify clinical significance of CB thawing in patients with paroxysmal atrial fibrillation.

METHODS

Two hundred ten patients with paroxysmal atrial fibrillation who underwent CB from January 2018 to October 2019 were analyzed. We compared the clinical outcomes of patients whose CB applications were completely stopped with only the double stop technique (DS group, n = 99) and patients with single stop (SS group, n = 111). In DS group, we performed double stop technique for all CB application regardless of phrenic nerve injury or the temperature of esophagus.

RESULTS

The atrial arrhythmia free-survival rate at 2 years after CB was significantly lower for the DS group than the SS group (76.8% vs 87.4%; p = 0.045). Complications occurred in 2 patients from the DS group and no complications were observed in patients from the SS group (p = 0.13). Mean procedural time was shorter in the DS group than in the SS group (53.1 vs 58.1 min; p = 0.046) CONCLUSION: DS group had higher recurrence rate than SS group. There was no significant difference regarding safety between both the groups. We found that the thawing process after single stop is very important for CB application.

Freedom from atrial arrhythmia and other clinical outcomes at 5 years and beyond after catheter ablation of atrial fibrillation: a systematic review and meta-analysis

AIMS

Catheter ablation of atrial fibrillation (AF) is now a mainstream procedure although long-term outcomes are uncertain. We performed a systematic review and meta-analysis of procedural outcomes at 5 years and beyond.

METHODS AND RESULTS

We searched PubMed and Embase and after the screening, identified 73 studies (67 159 patients) reporting freedom from atrial arrhythmia, all-cause death, stroke, and major bleeding at ≥5 years after AF ablation. The pooled mean age was 59.7y, 71.5% male, 62.2% paroxysmal AF, and radiofrequency was used in 78.1% of studies. Pooled incidence of freedom from atrial arrhythmia at 5 years was 50.6% (95%CI 45.5-55.7%) after a single ablation and 69.7% [95%CI (confidence interval) 63.8-75.3%) after multiple procedures. The incidence was higher among patients with paroxysmal compared with non-paroxysmal AF after single (59.7% vs. 33.3%, p = 0.002) and multiple (80.8% vs. 60.6%, p < 0.001) ablations but was comparable between radiofrequency and cryoablation. Pooled incidences of other outcomes were 6.0% (95%CI 3.2-9.7%) for death, 2.4% (95%CI 1.4-3.7%) for stroke, and 1.2% (95%CI 0.8-2.0%) for major bleeding at 5 years. Beyond 5 years, freedom from arrhythmia recurrence remained largely stable (52.3% and 64.7% after single and multiple procedures at 10 years), while the risk of stroke and bleeding increased over time.

CONCLUSION

Nearly 70% of patients having multiple ablations remained free from atrial arrhythmia at 5 years, with the incidence slightly decreasing beyond this period. Risk of death, stroke, and major bleeding at 5 years were low but increased over time, emphasizing the importance of long-term thromboembolism prevention and bleeding risk management.

Outcomes of adjunct posterior wall isolation in atrial fibrillation patients with cardiac implantable electronic devices

BACKGROUND

Although pulmonary vein isolation (PVI) remains the cornerstone of catheter ablation of atrial fibrillation (AF), several studies have illustrated clinical benefits associated with PVI with posterior wall isolation (PWI).

METHODS

This retrospective study investigated the outcomes of PVI alone versus PVI+PWI performed using the cryoballoon in patients with cardiac implantable electronic devices (CIEDs) and paroxysmal AF (PAF) or persistent AF (PersAF).

RESULTS

Acute PVI was achieved in all patients using cryoballoon ablation. Compared to PVI alone, PVI+PWI was associated with longer cryoablation, fluoroscopy, and total procedure times. Adjunct radiofrequency was required to complete PWI in 29/77 patients (37.7%). Adverse events were similar with PVI alone versus PVI+PWI. But at 24 ± 7 months of follow-up, not only cryoballoon PVI+PWI was associated with improved freedom from recurrent AF (74.3% vs. 46.0%, P = .007) and all atrial tachyarrhythmias (71.4% vs. 38.1%, P = .001) in patients with PersAF, cryoballoon PVI+PWI also yielded greater freedom from AF (88.1% vs. 63.7%, P = .003) and all atrial tachyarrhythmias (83.3% vs. 60.8%, P = .008) in those with PAF. Additionally, PVI+PWI was associated with higher reductions in atrial tachyarrhythmia burden (97.9% vs. 91.6%, P < .001), need for cardioversion (5.2% vs. 23.6%, P < .001) and repeat catheter ablation (10.4% vs. 26.1%, P = .005), and a longer time-to-arrhythmia recurrence (16 ± 6 months vs. 8 ± 5 months, P < .001) in both PersAF and PAF patients.

CONCLUSION

In CIED patients with PersAF or PAF, cryoballoon PVI+PWI is associated with a greater freedom from recurrent AF and atrial tachyarrhythmias, as compared to PVI alone during long-term follow-up.

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

Objectives

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

Methods

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

Results

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

Conclusion

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

Systematic review registration

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

Cryoballoon Ablation for Treatment of Atrial Fibrillation in a Chinese Population: Five-Year Outcomes and Predictors of Recurrence After a Single Procedure

Background

The 5-year outcomes and predictors of atrial fibrillation (AF) recurrence following cryoballoon (CB) ablation in Chinese population remain scarce. Our aim was to report 5-year outcomes and predictors of AF recurrence following a single CB ablation procedure in a Chinese population.

Methods

From December 2013 to August 2016, we included 256 consecutive patients (mean age: 58 ± 10.9 years old; female: 41.0%) with paroxysmal or persistent AF successfully underwent first-generation CB ablation at Fuwai hospital in this prospective study. All patients were followed at least 5 years or when there was recurrent AF. Independent predictors of AF recurrence were determined by Cox proportional hazards regression analysis.

Results

The 5-year success rate after pulmonary vein isolation (PVI) by a single procedure was 59.4%. The recurrence rate was the highest (14.5%) within the first year after the index procedure, and then stabilized. Patients with paroxysmal AF had a higher incidence of freedom from AF recurrence than patients with persistent AF (63.2% vs. 36.4%, log-rank P &lt; 0.01). The overall incidence of complications related to CB ablation was 7.8%. Phrenic nerve injury (PNI) was the most common complication, with an incidence of 3.5%, and patients with PNI were recovered within the 1-year follow-up. Only persistent AF (HR 1.72, 95%CI 1.028–2.854, P &lt; 0.05) was significantly and independently associated with an increased risk of AF recurrence after adjusting for other factors.

Conclusion

Pulmonary vein isolation using CB ablation was safe and effective with an acceptable complication and 5-year success rate in a Chinese population with AF, and persistent AF was the independent predictor for 5-year AF recurrence after a single CB ablation procedure.

Higher FT4 level within the normal range predicts the outcome of cryoballoon ablation in paroxysmal atrial fibrillation patients without structural heart disease

BACKGROUND

Accumulated evidence has indicated that a high-normal FT4 level is an independent risk factor for the clinical progression of AF. However, the association between elevated FT4 concentration within the normal range and AF recurrence after cryoballoon ablation in China is unknown.

METHODS

This retrospective and observational study included 453 AF patients who underwent cryoballoon ablation from January 2016 to August 2018. Patients were classified into quartiles based on preprocedural serum FT4 concentration. The clinical characteristics of the patients and the long-term rate of AF recurrence after ablation were assessed.

RESULTS

After a mean follow-up period of 17.4 ± 9.0 months, 91 (20.1%) patients suffered from AF recurrence. The AF recurrence rate by FT4 quartile was 17.7%, 19.0%, 21.4%, and 22.3% for participants with FT4 in quartile 1, 2, 3, and 4, respectively (p < .001). On multivariate Cox regression, FT4 concentration (HR: 1.187, 95% CI: 1.093-1.290, p < .001) and left atrial diameter (HR: 1.052, 95% CI: 1.014-1.092, p = .007) were significant predictors of AF recurrence. When stratifying for AF type, the rate of postoperative recurrence was independently increased as FT4 concentration increased in paroxysmal AF, but not in persistent AF (p < .001 in paroxysmal AF and p = .977 in persistent AF).

CONCLUSION

Higher FT4 level within the normal range predicted the outcome of cryoballoon ablation in Chinese paroxysmal AF patients without structural heart disease.

Cardiac Computed Tomography-Derived Left Atrial Volume Index as a Predictor of Long-Term Success of Cryo-Ablation in Patients With Atrial Fibrillation

Patients with symptomatic, drug-refractory atrial fibrillation (AF) are frequently treated with catheter ablation. Cryo-ablation has been established as an alternative to radiofrequency ablation but long-term outcome data are still limited. This study aimed at elucidating the influence of the left atrial volume index (LAVI), derived from cardiac computed tomography (cCT) data, on the long-term outcome of ablation-naïve AF patients, after their first cryo-ablation. 415 patients (n = 290 [69.90%] male, 60.00 [IQR: 53.00 to 68.00] years old) who underwent a cCT and subsequent cryo-ablation index procedure were included in this single centre retrospective data analysis. A composite end point was defined (AF on electrocardiogram and/or electric cardioversion and/or re-do). Patients were closely followed for a year and then contacted for long-term follow-up after a median of 53.00 months (IQR: 34.50 to 73.00). Statistical analyses of the outcome and predictors of AF recurrence were conducted. In 224 patients (53.98%) no evidence of AF recurrence could be found. LAVI differed significantly between the positive and adverse (AF recurrence) outcome group (49.96 vs 56.07 ml/m², p < 0.001). Cox regression analyses revealed cCT LAVI (HR: 1.022, 95% CI: 1.013 to 1.031, p < 0.001), BMI (HR: 1.044, 95% CI: 1.005 to 1.084, p < 0.05) and the type of AF (HR: 1.838 for nonparoxysmal AF, 95% CI: 1.214 to 2.781, p < 0.01) to be effective predictors of AF recurrence. A prognostic cCT LAVI cut-off value of 51.99 ml/m² was calculated and must be validated in future prospective studies. In conclusion, LAVI is an accurate, yet underutilized predictor of AF recurrence after pulmonary vein isolation with cryo-energy and scores for calculating AF recurrence or progression risks might underemphasize the importance of CT-derived LAVI as a predictive factor.