Purpose

A new cryoballoon (CB) technology (POLARx™; Boston Scientific) for pulmonary vein (PV) isolation in patients with atrial fibrillation (AF) has recently been introduced. The aim of this study was to evaluate procedural and biophysical parameters resulting in acute PV isolation when using this new CB.

Methods

We assessed the first 69 consecutive patients indicated for AF ablation who underwent PV isolation by means of a novel CB system. Procedural metrics were prospectively recorded.

Results

A total of 274 PVs were targeted in 69 patients. PV isolation was achieved in all patients by means of cryoablation alone. The median time to isolation (TTI) was 44 [31–68] s (median temperature at TTI = − 49 [− 53 to − 41] °C). The median duration of CB ablation was 180 [180 to 240] s. The median nadir temperature was − 56.0 [− 61 to − 52] °C, and the median thaw time to 0 °C was 18 [15–21] s. The median grade of PV occlusion was 4 [3 to 4]. On the basis of ROC analysis, we defined the following cut-off values for acute PV isolation: − 56 °C for nadir temperature (sensitivity = 73.3%, specificity = 64.6%, AUC = 0.716; positive predictive value = 88.1%), 30 s for TTT (60.2%, 53.3%, 0.578; 79.7%), thaw time > 17 s (65.3%, 70.0%, 0.709; 86.9%), and grade of PV occlusion = 4 (79.4%, 66.7%, 0.738; 88.5%). No major procedure-related adverse events were observed at 30-day post-procedure.

Conclusions

The new POLARx™ CB appears to be effective and safe. A nadir temperature of − 56 °C, a thaw time to 0 °C ≥ 17 s, and complete PV occlusion were the best predictors of acute PV isolation.

Clinical trial registration

Catheter Ablation of Arrhythmias with a High-Density Mapping System in Real-World Practice (CHARISMA). URL: http://clinicaltrials.gov/Identifier: NCT03793998. Registration date: January 4, 2019.

中文翻译：

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使用新型冷冻球囊技术时有效急性肺静脉隔离的关键特征：来自 CHARISMA 注册的见解

目的

最近推出了一种新的冷冻球囊 (CB) 技术（POLARx™；波士顿科学公司），用于隔离心房颤动 (AF) 患者的肺静脉 (PV)。本研究的目的是评估在使用这种新的 CB 时导致急性 PV 隔离的程序和生物物理参数。

方法

我们评估了前 69 名接受 AF 消融的连续患者，这些患者通过新型 CB 系统进行了 PV 隔离。前瞻性地记录了程序性指标。

结果

在 69 名患者中总共有 274 个 PV。所有患者均通过单独冷冻消融实现 PV 隔离。隔离时间 (TTI) 的中位数为 44 [31–6​​8] 秒（TTI 的中位数温度 = − 49 [− 53 至 − 41] °C）。CB 消融的中位持续时间为 180 [180 至 240] 秒。中位最低点温度为 − 56.0 [− 61 至 − 52] °C，解冻至 0 °C 的中位时间为 18 [15–21] 秒。PV 闭塞的中位等级为 4 [3 至 4]。在 ROC 分析的基础上，我们定义了以下急性 PV 隔离的临界值：- 56 °C 的最低点温度（敏感性 = 73.3%，特异性 = 64.6%，AUC = 0.716；阳性预测值 = 88.1%）， TTT 为 30 秒（60.2%、53.3%、0.578；79.7%），解冻时间 > 17 秒（65.3%、70.0%、0.709；86.9%），PV 闭塞等级 = 4（79.4%、8.37.7%） ; 88.5%)。

结论

新的 POLARx™ CB 似乎有效且安全。− 56 °C 的最低温度、0 °C 的解冻时间≥ 17 s 和完全 PV 闭塞是急性 PV 隔离的最佳预测指标。

临床试验注册

在现实世界实践中使用高密度映射系统 (CHARISMA) 对心律失常进行导管消融。URL：http://clinicaltrials.gov/Identifier：NCT03793998。注册日期：2019年1月4日。