Comparison of irrigated electrode designs for radiofrequency ablation of myocardium.
Comparison of irrigated electrode designs for radiofrequency ablation of myocardium.
复制标题
心肌射频消融冲洗电极设计的比较。
DOI：
10.1023/a:1013241927388
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发表时间：
2001
期刊：
影响因子：
--
通讯作者：
Schwartzman,D
中科院分区：
文献类型：
--
作者：
Demazumder,D;Mirotznik,MS;Schwartzman,D
背景：先前的报告已经证明，通过灌注电极输送到心肌的射频能量导致比非灌注电极更大体积的消融损伤。不同的灌注电极设计已被利用;没有直接的comparisons have been reported.Purpose：To comparison different irrigated electrode designs.Methods：三个灌注电极设计进行了比较对照组（非灌注电极）：1.内部; 2.淋浴头; 3.鞘对于每个电极，在消融之前，对沿着电极外表面的冲洗液流进行多普勒超声心动图评估。消融是在玻璃化全血灌注系统中进行的。评估电极、电极-内膜界面和心肌内温度，以及消融电路阻抗、总输送能量、损伤和电极形态。使用室温生理盐水作为灌洗液，以20 cc/min的速率输送。电极-endoadrenal界面血流以0和0.26 m/s的速率进行评估。结果：冲洗剂包含在内部电极设计中，因此电极外表面在冲洗过程中没有明显的流动。冲洗剂主要径向地远离喷头电极设计扩散，在冲洗孔处产生相对高的电极外表面流，但在其他地方较低。冲洗剂平行于鞘电极设计的电极外表面行进并包裹电极外表面，产生相对温和但均匀的流动。与非冲洗电极相比，通过每个冲洗电极进行消融产生更大的消融能量沉积和更大的损伤尺寸。灌注不一定能防止界面沸腾，界面沸腾可能发生在不间断的射频能量沉积和损伤生长过程中。3种灌注设计的结果不一致。通过内部电极设计施加射频能量的持续时间明显短于其他设计，阻抗升高缩短了持续时间。这产生了最小的总射频能量沉积和最小的消融损伤体积。相对于此，使用喷头设计的持续时间明显更长，与更大的总能量沉积和更大的病变体积相关。鞘管的设计允许最长的持续时间，与最大的总能量沉积和病变volume.Conclusions：虽然每个灌注电极的设计产生了较大的病变比非灌注电极，他们是不可比的。消融持续时间和损伤大小与沿着电极外表面的血流直接相关。
Background:Previous reports have demonstrated that radiofrequency energy delivered to myocardium via an irrigated electrode results in a more voluminous ablation lesion than a non-irrigated electrode. Different irrigated electrode designs have been utilized; no direct comparisons have been reported.Purpose:To compare different irrigated electrode designs.Methods:Three irrigation electrode designs were compared to a control (non-irrigated electrode) group: 1. internal; 2. showerhead; 3. sheath. For each electrode, prior to ablation Doppler echocardiographic assessment of the irrigant flow along the electrode outer surface was performed. Ablation was performedin vitroutilizing a whole blood-superfused system. Electrode, electrode–endocardial interface, and intramyocardial temperatures were assessed, as were ablation circuit impedance, total delivered energy, and lesion and electrode morphology. Room temperature normal saline was utilized as the irrigating fluid, delivered at 20 cc/min. Electrode–endocardial interfacial blood flow was assessed at rates of 0 and 0.26 m/s.Results:Irrigant was contained within the internal electrode design and therefore the electrode outer surface manifested no significant flow during irrigation. Irrigant spread primarily radially away from the showerhead electrode design, yielding relatively high electrode outer surface flow at the irrigation holes, but low elsewhere. Irrigant traveled in parallel to and enveloped the electrode outer surface of the sheath electrode design, yielding relatively moderate but uniform flow.Ablation via each of the irrigated electrodes yielded greater ablation energy deposition and larger lesion dimensions than the non-irrigated electrode. Irrigation didnotnecessarily prevent interfacial boiling, which could occur during uninterrupted radiofrequency energy deposition and lesion growth. The results for the 3 irrigation designs were incongruent. The duration of radiofrequency energy application via the internal electrode design was significantly shorter than the other designs, curtailed by impedance rise. This yielded the smallest total radiofrequency energy deposition and smallest ablation lesion volume. Relative to this, duration using the showerhead design was significantly longer, associated with greater total energy deposition and larger lesion volume. The sheath design permitted the longest duration, associated with the largest total energy deposition and lesion volume.Conclusions:Although each of the irrigated electrode designs yielded larger lesions than the non-irrigated electrode, they were not comparable. Ablation duration and lesion size were directly correlated with flow along the electrode outer surface.