Lequerica Juan L, Berjano Enrique J, Herrero Maria, Hornero Fernando
Cardiac Research Laboratory, Instituto de Biomedicina, Spanish Council for Scientific Research, CSIC, Valencia, Spain.
J Cardiovasc Electrophysiol. 2008 Nov;19(11):1188-93. doi: 10.1111/j.1540-8167.2008.01229.x. Epub 2008 Jun 4.
Cooled Balloon Prevents Thermal Injury During RF Ablation.
The use of a cooled intraesophageal balloon has recently been proposed to minimize the risk of thermal injury in the esophagus during radiofrequency (RF) ablation of the left atrium. However, the capacity of this device to adequately protect the esophagus under different procedural and anatomical conditions remains unknown.
An agar phantom-based model was built that provided temperature readings not only on the cooled balloon (T(b)) but also at a hypothetical point between the esophageal lumen and myocardium at a distance of 2 mm (T(2-mm)). The RF ablations were conducted considering two anatomical factors (total distance between the electrode and balloon and flow rate around the electrode) and two procedural factors (angle and pressure between the electrode and agar surface). The results show that most of the parameters studied have no significant influence on the temperature measured on the cooled balloon (T(b)), the exception being a variation in the flow rate, which was found to influence the temperature. On the other hand, T(2-mm) was affected to a great extent by all the factors considered, the smallest influence being that of the contact pressure. The results also suggest that when an intraesophageal balloon is employed, the applied power is not a good predictor either of the temperature on the balloon or of the temperature measured at a distance 2 mm away.
The results suggest that a cooled intraesophageal balloon provides effective thermal protection of the esophageal lumen. However, under certain circumstances, the temperature reached at a distance 2 mm away could possibly put at risk the integrity of the inner layers of the esophagus.
冷却球囊可防止射频消融过程中的热损伤。
最近有人提出使用冷却的食管内球囊，以尽量降低左心房射频消融期间食管热损伤的风险。然而，该装置在不同手术和解剖条件下充分保护食管的能力仍不明确。
构建了一个基于琼脂模型的模型，该模型不仅能提供冷却球囊上的温度读数（T(b)），还能提供食管腔与心肌之间距离2毫米处假设点的温度读数（T(2-mm)）。考虑两个解剖因素（电极与球囊之间的总距离以及电极周围的流速）和两个手术因素（电极与琼脂表面之间的角度和压力）进行射频消融。结果表明，所研究的大多数参数对冷却球囊上测得的温度（T(b)）没有显著影响，流速变化是个例外，发现其会影响温度。另一方面，T(2-mm)在很大程度上受到所有考虑因素的影响，影响最小的是接触压力。结果还表明，当使用食管内球囊时，施加的功率既不是球囊温度的良好预测指标，也不是距离2毫米处测得温度的良好预测指标。
结果表明，冷却的食管内球囊可为食管腔提供有效的热保护。然而，在某些情况下，距离2毫米处达到的温度可能会使食管内层的完整性面临风险。
