Knecht Sven, Reichlin Tobias, Pavlovic Nikola, Schaer Beat, Osswald Stefan, Sticherling Christian, Kühne Michael
Department of Cardiology, University Hospital Basel, Petersgraben 4, 4031, Basel, Switzerland,
J Interv Card Electrophysiol. 2015 Sep;43(3):297-306. doi: 10.1007/s10840-015-0002-8. Epub 2015 Apr 30.
Contact force (CF) sensing during radiofrequency (RF) ablation allows controlling lesion size. The aim of this study was to analyze the impact of catheter tip location and orientation on the association of CF and impedance decrease.
We retrospectively analyzed RF applications from 32 patients undergoing catheter ablation for paroxysmal atrial fibrillation using a force-sensing catheter and 3D mapping system. CF, catheter location and orientation relative to the tissue during ablation as well as the absolute impedance decrease during the first 20 s of ablation as a surrogate for lesion effectiveness were analyzed for 791 RF applications.
While a higher CF was achieved around the right pulmonary veins (12.5 vs. 11.4 g, p = 0.045), a lower median absolute impedance decrease within the first 20 s was seen around the right veins compared to the left veins (9.3 vs. 10.2 Ω, p = 0.02). With different catheter orientations relative to the tissue, higher CF and impedance decrease was seen when the catheter was orientated parallel or oblique to the tissue (30°-145°) as compared perpendicularly (0-30°) with a median CF of 13.2 vs. 8.0 g (p < 0.001) and a median impedance decrease during the first 20 s of 11 vs. 7 Ω (p < 0.001). Importantly, achieved CF, baseline impedance, catheter orientation and location all independently predicted the initial absolute and relative impedance decrease in a multivariable linear regression model (p < 0.05).
The effectiveness of RF ablation lesions, as assessed by the initial impedance decrease, is not only dependent on the achieved catheter CF but also on catheter orientation and location.
在射频（RF）消融过程中进行接触力（CF）传感可控制消融灶大小。本研究的目的是分析导管尖端位置和方向对CF与阻抗降低之间关联的影响。
我们回顾性分析了32例接受阵发性心房颤动导管消融患者使用力传感导管和三维标测系统进行的RF应用。对791次RF应用分析了消融期间CF、导管相对于组织的位置和方向以及消融最初20秒内的绝对阻抗降低情况，以此作为消融灶有效性的替代指标。
虽然右肺静脉周围实现了更高的CF（12.5克对11.4克，p = 0.045），但与左肺静脉相比，右肺静脉周围在最初20秒内的中位绝对阻抗降低幅度较小（9.3欧姆对10.2欧姆，p = 0.02）。当导管相对于组织处于不同方向时，与垂直方向（0 - 30°）相比，导管与组织平行或倾斜（30° - 145°）时观察到更高的CF和阻抗降低，中位CF分别为13.2克对8.0克（p < 0.001），最初20秒内的中位阻抗降低分别为11欧姆对7欧姆（p < 0.001）。重要的是，在多变量线性回归模型中，实现的CF、基线阻抗、导管方向和位置均独立预测了初始绝对和相对阻抗降低情况（p < 0.05）。
通过初始阻抗降低评估的RF消融灶有效性不仅取决于实现的导管CF，还取决于导管方向和位置。
