Chorro F J, Mainar L, Sanchis J, Cánoves J, Llavador E, Such L M, Cerdá M, López-Merino V, Such L
Service of Cardiology, Valencia University Clinic Hospital, Spain.
Pacing Clin Electrophysiol. 2001 Feb;24(2):147-56. doi: 10.1046/j.1460-9592.2001.00147.x.
High resolution mapping techniques are used to analyze the changes in atrial activation patterns produced by contiguous RF induced lesions. In 12 Langendorff-perfused rabbit hearts, left atrial activation maps were obtained before and after RF induction of epicardial lesions following a triple-phase sequential protocol: (phase 1) three separate lesions positioned vertically in the central zone of the left atrial wall; (phase 2) the addition of two lesions located between the central lesion and the upper and lower lesions; and (phase 3) the placement of four additional lesions between those induced in the previous phases. In six additional experiments a pathological analysis of the individual RF lesions was performed. In phase 1 (lesion diameter = 2.8+/-0.2 mm, gap between lesions = 3+/-0.8 mm), the activation process bordered the lesions line in two (250-ms cycles) and four experiments (100-ms cycles). In phase 2, activation bordered the lesions line in eight (250-ms cycles, P < 0.01 vs control) and nine experiments (100-ms cycles, P < 0.001), and in phase 3 this occurred in all experiments except one (both cycles, P < 0.001 vs control). In the experiments with conduction block, the increment of the interval between activation times proximal and distal to the lesions showed a significant correlation to the length of the lesions (r = 0.68, P < 0.05, 100-ms cycle). In two (17%) experiments, sustained regular tachycardias were induced with reentrant activation patterns around the lesions line. In conclusion, in this acute model, atrial RF lesions with intact tissue gaps of 3 mm between them interrupt conduction occasionally, and conduction block may be frequency dependent. Lesion overlap is required to achieve complete conduction block lines. Tachycardias with reentrant activation patterns around a lesions line may be induced.
高分辨率标测技术用于分析连续射频诱导损伤所产生的心房激活模式的变化。在12个经Langendorff灌注的兔心脏中，按照三相序贯方案在射频诱导心外膜损伤前后获取左心房激活图：（阶段1）在左心房壁中央区域垂直放置三个单独的损伤；（阶段2）在中央损伤与上下损伤之间添加两个损伤；（阶段3）在前一阶段诱导的损伤之间再放置四个损伤。在另外六个实验中，对单个射频损伤进行了病理分析。在阶段1（损伤直径 = 2.8±0.2毫米，损伤之间的间隙 = 3±0.8毫米），在两个实验（250毫秒周期）和四个实验（100毫秒周期）中，激活过程沿着损伤线边缘进行。在阶段2，在八个实验（250毫秒周期，与对照相比P < 0.01）和九个实验（100毫秒周期，P < 0.001）中，激活沿着损伤线边缘进行，在阶段3，除了一个实验外（两个周期，与对照相比P < 0.001），在所有实验中均如此。在伴有传导阻滞的实验中，损伤近端和远端激活时间之间的间隔增量与损伤长度呈显著相关性（r = 0.68，P < 0.05，100毫秒周期）。在两个（17%）实验中，围绕损伤线出现了具有折返激活模式的持续性规则心动过速。总之，在这个急性模型中，其间有3毫米完整组织间隙的心房射频损伤偶尔会中断传导，并且传导阻滞可能与频率有关。需要损伤重叠才能形成完整的传导阻滞线。围绕损伤线具有折返激活模式的心动过速可能会被诱发。
