Pulmonary Vein Anatomy is Associated with Cryo Kinetics during Cryoballoon Ablation for Atrial Fibrillation

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 < 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 < 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.

The influence of metabolic syndrome on atrial fibrillation recurrence: five-year outcomes after a single cryoballoon ablation procedure

BACKGROUND

Metabolic syndrome (MetS) has been reported as a risk factor of atrial fibrillation (AF) recurrence after radiofrequency catheter ablation. This study aimed to investigate the long-term influence of MetS on paroxysmal AF recurrence after a single cryoballoon ablation procedure, which was scarcely investigated yet in Chinese population.

METHODS

In total, 137 paroxysmal AF patients who had successfully completed a single cryoballoon ablation procedure at Fuwai Hospital, Beijing, China from December 2013 to October 2015 were enrolled. Excepting for patients with AF recurrence, all patients were followed up for no less than five years. Independent predictors of AF recurrence were determined by Cox proportional hazards regression analysis.

RESULTS

Among 137 paroxysmal AF patients, 91 patients (66.4%) had successfully achieved overall five-year follow-up after a single cryoballoon ablation procedure, and 44 patients (32.1%) had MetS. Patients with MetS had a significant lower incidence of freedom from AF recurrence than those without MetS (50.0% vs. 74.2%, log-rank P < 0.01) during the five-year follow-up. MetS (HR = 1.95, 95% CI: 1.069−3.551, P = 0.030) was an independent predictor of AF recurrence after adjusting for multiple factors. After the second year post cryoballoon ablation procedure, the recurrence rate of AF gradually increased in patients with MetS, in contrast, decreased recurrence rate of AF in patients without MetS.

CONCLUSIONS

MetS is an independent predictor for five-year AF recurrence after a single cryoballoon ablation procedure in paroxysmal AF patients. Combination therapy of AF and MetS may improve the long-term outcomes of AF patients.

Impact of pulmonary vein ovality index on cooling kinetics and acute success of atrial fibrillation ablation with the third-generation cryoballoon catheter

INTRODUCTION

Atrial fibrillation (AF) is the most common arrhythmia, increasing the risk of stroke and all-cause mortality. Pulmonary vein isolation (PVI) with cryoballoon ablation (CBA) is a widely accepted approach for invasive treatment of patients with AF. CBA effectiveness is considered to be strongly dependent upon the anatomy of pulmonary veins, mainly the ovality of pulmonary veins' ostia. However, most published results refer to the second-generation cryoballoon.

AIM

To investigate the impact of the ovality index (OI) of pulmonary veins (PVs) on cryokinetic parameters and acute effectiveness of PVI with the third-generation cryoballoon catheter.

MATERIAL AND METHODS

We enrolled 54 patients with documented drug-refractory, symptomatic paroxysmal and persistent AF, who underwent CBA with the third-generation cryoballoon between March 2019 and July 2020. Prior to the procedure all patients underwent computed tomography (CT) scans to evaluate anatomy of PVs and calculate the ovality indices for each vein. Analyzed patients were divided into two equal groups depending on the mean OI for all veins.

RESULTS

No differences were observed in acute effectiveness, total procedure time, freeze time, need for additional applications and complications in the group with lower (OI < 1.27) and higher (OI > 1.27) OI values. Remarkably, fluoroscopy time was even slightly shorter (p = 0.046) in patients with high OI.

CONCLUSIONS

In the analyzed population, increased pulmonary vein OI had no negative effect on the CBA procedure performed with the third-generation cryoballoon catheter; therefore it can be considered as a more comprehensive single-shot PVI tool.