Harvard-Thorndike Electrophysiology Institute, Cardiovascular Division, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts.
Biosense Webster, Research and Development, Haifa, Israel.
JACC Clin Electrophysiol. 2018 Apr;4(4):467-479. doi: 10.1016/j.jacep.2017.11.018. Epub 2018 Feb 2.
This study sought to examine the biophysical properties of high-power and short-duration (HP-SD) radiofrequency ablation for pulmonary vein isolation.
Pulmonary vein isolation is the cornerstone of atrial fibrillation ablation. However, pulmonary vein reconnection is frequent and is often the result of catheter instability, tissue edema, and a reversible nontransmural injury. We postulated that HP-SD ablation increases lesion-to-lesion uniformity and transmurality.
This study included 20 swine and a novel open-irrigated ablation catheter with a thermocouple system able to record temperature at the catheter-tissue interface (QDOT Micro Catheter). Step 1 compared 3 HP-SD ablation settings: 90 W/4 s, 90 W/6 s, and 70 W/8 s in a thigh muscle preparation. Ablation at 90 W/4 s was identified as the best compromise between lesion size and safety parameters, with no steam-pop or char. In step 2, a total of 174 single ablation applications were performed in the beating heart and resulted in 3 (1.7%) steam-pops, all occurring at catheter-tissue interface temperature ≥85°C. Additional 233 applications at 90 W/4 s and temperature limit of 65°C were applied without steam-pop. Step 3 compared the presence of gaps and lesion transmurality in atrial lines and pulmonary vein isolation between HP-SD (90 W/4 s, T ≤65°C) and standard (25 W/20 s) ablation.
HP-SD ablation resulted in 100% contiguous lines with all transmural lesions, whereas standard ablation had linear gaps in 25% and partial thickness lesions in 29%. Ablation with HP-SD produced wider lesions (6.02 ± 0.2 mm vs. 4.43 ± 1.0 mm; p = 0.003) at similar depth (3.58 ± 0.3 mm vs. 3.53 ± 0.6 mm; p = 0.81) and improved lesion-to-lesion uniformity with comparable safety end points.
In a preclinical model, HP-SD ablation (90 W/4 s, T ≤65°C) produced an improved lesion-to-lesion uniformity, linear contiguity, and transmurality at a similar safety profile of conventional ablation.
本研究旨在探讨高功率短时间（HP-SD）射频消融用于肺静脉隔离的生物物理特性。
肺静脉隔离是房颤消融的基石。然而，肺静脉再连接很常见，通常是由于导管不稳定、组织水肿和可逆的非穿透性损伤所致。我们假设 HP-SD 消融可提高病变间的均匀性和穿透性。
本研究纳入 20 头猪和一种新型开放式灌流消融导管，该导管配备了能够记录导管-组织界面温度的热电偶系统（QDOT 微导管）。第 1 步比较了 3 种 HP-SD 消融设置：在大腿肌肉准备中，90 W/4 s、90 W/6 s 和 70 W/8 s。90 W/4 s 的消融被确定为在病变大小和安全参数之间的最佳折衷，没有蒸汽爆或炭化。在第 2 步，共在跳动的心脏中进行了 174 次单消融应用，导致 3 次（1.7%）蒸汽爆，均发生在导管-组织界面温度≥85°C 时。在 90 W/4 s 和 65°C 的温度限制下，再应用 233 次无蒸汽爆。第 3 步比较了 HP-SD（90 W/4 s，T≤65°C）和标准（25 W/20 s）消融之间心房线和肺静脉隔离中的间隙存在情况和病变穿透性。
HP-SD 消融导致 100%连续线，所有病变均为全层穿透性，而标准消融有 25%的线性间隙和 29%的部分厚度病变。HP-SD 消融产生的病变较宽（6.02±0.2 mm 比 4.43±1.0 mm；p=0.003），但深度相似（3.58±0.3 mm 比 3.53±0.6 mm；p=0.81），并且在类似的安全终点下改善了病变间的均匀性。
在临床前模型中，HP-SD 消融（90 W/4 s，T≤65°C）在类似的常规消融安全性特征下产生了改善的病变间均匀性、线性连续性和穿透性。
