Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas, USA.
Electrophysiology Clinical Research and Innovations, Texas Heart Institute, Houston, Texas, USA.
J Cardiovasc Electrophysiol. 2021 Mar;32(3):704-712. doi: 10.1111/jce.14911. Epub 2021 Feb 2.
Few studies have examined heat transfer and thermal injury on the epiesophageal surface during radiofrequency application, or compared the risk of esophageal thermal injury between standard and high-power, short-duration (HPSD) ablation. We studied the thermodynamics of HPSD and standard ablation at different tissue interfaces between the left atrium and esophagus, focusing on epiesophageal temperature changes and thermal injury.
Fresh porcine heart and esophageal sections were secured to a custom holder and submerged in a temperature-controlled, circulating water bath. During ablation, thermistors recorded temperatures at the catheter tip-atrial interface, epiesophageal-atrial interface, and esophageal lumen. Samples were ablated in triplicate with the following parameters: contact force (15/25g), power (10/20/30 W standard; 40/45/50 W HPSD), and duration (10/20/30 s standard; 5/10/15 s HPSD). Epiesophageal and endoluminal temperature rises were greater in HPSD than in standard ablation (epiesophageal: 5.9 ± 5.6 vs. 2.2 ± 2.0°C, p < .01; endoluminal: 0.7 ± 0.5 vs. 0.4 ± 0.2°C, p < .01). Six of 30 HPSD ablations and 1 of 26 standard ablations caused esophageal injury. The delay between the peak epiesophageal and endoluminal temperatures was greater in HPSD than in standard ablation (24.2 ± 22.1 vs. 13.0 ± 11.0 s, p = .023). Likewise, the peak epiesophageal surface temperature differed more from the concurrent endoluminal temperature in HPSD ablation (5.1 ± 5.3 vs. 1.7 ± 2.0°C, p < .01).
Endoluminal temperature underestimates epiesophageal surface temperature substantially during HPSD ablation. Visible epiesophageal injury was associated with a 2.2 ± 2.1°C rise in endoluminal temperature, corresponding to a 10.2 ± 6.5°C rise in epiesophageal temperature.
鲜有研究关注射频消融过程中食道表面的热传递和热损伤，也鲜有研究比较标准功率与高功率短时间（HPSD）消融的食道热损伤风险。我们研究了左心房与食道不同组织界面间 HPSD 与标准消融的热力学特性，重点关注食道表面温度变化和热损伤。
将新鲜猪心和食道切片固定在定制夹具上，置于温度可控的循环水浴中。消融过程中，热敏电阻记录导管尖端-心房界面、食道-心房界面和食道腔的温度。以以下参数重复消融 3 次：接触力（15/25g）、功率（标准 10/20/30W；HPSD 40/45/50W）和时间（标准 10/20/30s；HPSD 5/10/15s）。HPSD 消融时食道表面和腔内温度上升高于标准消融（食道表面：5.9±5.6 比 2.2±2.0°C，p<0.01；食道腔内：0.7±0.5 比 0.4±0.2°C，p<0.01）。30 次 HPSD 消融中有 6 次和 26 次标准消融中有 1 次导致食道损伤。HPSD 比标准消融的食道表面和腔内温度峰值之间的延迟更大（24.2±22.1 比 13.0±11.0s，p=0.023）。同样，HPSD 消融时食道表面温度峰值与同期食道腔内温度差值更大（5.1±5.3 比 1.7±2.0°C，p<0.01）。
HPSD 消融时，腔内温度明显低估食道表面温度。可见食道损伤与腔内温度升高 2.2±2.1°C 相关，对应食道表面温度升高 10.2±6.5°C。
