Inaba Osamu, Nagata Yasutoshi, Sekigawa Masahiro, Miwa Naoyuki, Yamaguchi Junji, Miyamoto Takamichi, Goya Masahiko, Hirao Kenzo
Department of Cardiology Musashino Red Cross Hospital Musashino Japan.
Heart Rhythm Center Tokyo Medical and Dental University Bunkyo-ku Tokyo Japan.
J Arrhythm. 2018 Apr 16;34(3):247-253. doi: 10.1002/joa3.12056. eCollection 2018 Jun.
The clinical impact of a decrease in impedance during radiofrequency catheter ablation (RFCA) has not been fully clarified. The aim of the study was to analyze the impact of impedance decrease and to determine its optimal cutoff value during RFCA.
We evaluated 34 consecutive patients (total 3264 lesions, mean age 66 ± 8.7 years, 10 females) who underwent their first ablation for atrial fibrillation (AF). The impedance decrease, average contact force (CF), application time, force-time integral (FTI), product of impedance decrease and application time (PIT), and the product of impedance decrease and FTI (PIFT) were measured for all lesions. Levels of cardiac troponin I (TrpI) were measured for assessment of myocardial injury. The incidence of intraprocedural pulmonary vein-left atrium reconnection or dormant conduction (reconnection) was determined. The relationships between the ablation parameters and the increase in TrpI (ΔTrpI) were evaluated. The predictive value of the parameters for reconnection was assessed using receiver operating characteristic (ROC) curve analysis.
Reconnection was detected in 18 patients. Average FTI and PIT were significantly correlated with ΔTrpI (FTI: = .19, = .0090, PIT: = .21, = .0058). PIFT was correlated with ΔTrpI and was the best of the three indexes (PIFT: = .29, = .0010). In ROC curve analysis, the area under the curve for predicting reconnection was 0.71 and the optimal cutoff value was 5200 for PIFT (sensitivity 78%, specificity 63%).
The combination of CF and a decrease in impedance could be important in the evaluation of myocardial lesions and reconnection during RFCA.
在射频导管消融术（RFCA）期间阻抗降低的临床影响尚未完全阐明。本研究的目的是分析阻抗降低的影响，并确定RFCA期间其最佳截断值。
我们评估了34例连续接受首次心房颤动（AF）消融术的患者（共3264个病灶，平均年龄66±8.7岁，10名女性）。测量了所有病灶的阻抗降低、平均接触力（CF）、施加时间、力-时间积分（FTI）、阻抗降低与施加时间的乘积（PIT）以及阻抗降低与FTI的乘积（PIFT）。测量心肌肌钙蛋白I（TrpI）水平以评估心肌损伤。确定术中肺静脉-左心房重新连接或隐匿传导（重新连接）的发生率。评估消融参数与TrpI升高（ΔTrpI）之间的关系。使用受试者工作特征（ROC）曲线分析评估参数对重新连接的预测价值。
在18例患者中检测到重新连接。平均FTI和PIT与ΔTrpI显著相关（FTI：r = 0.19，P = 0.0090；PIT：r = 0.21，P = 0.0058）。PIFT与ΔTrpI相关，并且是三个指标中最佳的（PIFT：r = 0.29，P = 0.0010）。在ROC曲线分析中，预测重新连接的曲线下面积为0.71，PIFT的最佳截断值为5200（敏感性78%，特异性63%）。
CF与阻抗降低的组合在RFCA期间心肌病灶和重新连接的评估中可能很重要。
