冷冻消融对犬心肌组织的损伤作用

Histopathological changes post cryoablation in canine myocardium

目的观察冷冻导管消融对犬心肌组织病理学的影响,探索冷冻能量的消融价值。方法对14只杂种犬进行心肌的冷冻消融,设置不同的消融温度和时间参数等(-25℃、4 min,-50℃、4 min,-75℃、4 min,-75℃、2 min,-75℃、6 min,-75℃、8 min),分别从心外膜和心内膜进行消融,并观察组织病理学改变及损伤范围。结果冷冻消融造成局灶的心肌组织坏死,灶边界清楚,周围组织无损伤。损伤的范围与冷冻温度和时间有关,这可有助于临床上冷冻标测和冷冻消融温度的选择和冷冻时间的设置。结论冷冻可造成心肌局部组织的局灶性坏死,是一种较好的备选消融能量。

Objective The purpose of this study was to observe histopathological changes post cryoablation in canine myocardium, to characterize the specific ablation lesion post cryoablation. Methods Cryothermal ablation was applied on myocardium （both epicardium and endocardium） of 14 mongrel dogs with different ablation parameters （ - 25℃ × 4 min, - 50℃ × 4 min, - 75℃ × 4 min, - 75℃ × 2 min, -75℃ ×6 min, -75℃ × 8 min）. Lesion dimensions and histopothologic changes were observed. Results The discrete, sharply delimited lesions were detected in cryoablated myocardium. Histologically, cryoablation in all temperatures studied induced heterogeneous necrosis of the myocardium. Lesion dimensions are related to freezing time and temperature. Conclusion Cryoablation is a feasible and preferably choice for clinical application due to its controllable myocardium lesions.