Koch三角基底部线性消融治疗常规消融方法困难的房室结折返性心动过速

Linear ablation at lower or mid level of Koch’s triangle in the treatment of atrioventricular nodal reentrant tachycardia refractory to conventional slow pathway modification

目的研究Koch三角基底部线性消融治疗常规消融方法困难的房室结折返性心动过速(AVNRT)的疗效和安全性。方法38例心内电生理证实为慢快型AVNRT病人,均经常规中位或下位法改良慢径消融放电10次以上,但心动过速仍能诱发者;或为消融术后复发患者。其中男性18例,女性20例,年龄9～76(466±185)岁。先于冠状静脉窦口上方进行线性消融(L1线),消融起点的心内电图为小A大V波,终点为大A大V波。如果仍能诱发心动过速,则按同样方法在Koch三角的中位水平进行线性消融(L2线)。结果所有病人线性消融均获成功,30例病人在L1线消融后心动过速不再诱发,另8例病人经L2线性消融后获成功。线性消融的平均点数(47±11)次。5例病人在整个消融放电过程中无交界性心律出现,6例病人的交界性心律在大A波时出现。线性消融前,共有36例患者具有房室传导的跳跃现象;线性消融成功后,16例病人仍有房室传导的跳跃现象,其中10例伴有单个心房回波,其余22例(58%)病人无跳跃和回波。手术过程中无1例病人发生房室阻滞。平均随访(104±42)个月,所有病人均无心动过速复发。结论对常规消融方法困难的AVNRT,Koch三角底部和/或中位水平的线性消融是一种安全、有效的方法。消融过程中出现交界性心律并非消融成功之必须。

Objective To study the efficacy and safety of linear ablation at Koch’s triangle in the treatment of the atrioventricualr nodal reentrant tachycardia(AVNRT) which is refractory to conventional slow pathway modification. Methods Thirty eight patients(18 men and 20 women) were included with a mean age of (46 6±18 5) years (range 9～76 years).All of them were diagnosed as AVNRT by electrophysiological study and refractory to conventional slow pathway modification for no less than 10 times radiofrequency energy(RF) deliveries. Linear lesion was first performed at the level of upper margin of the coronary sinus orifice (L1), starting with small A and large V wave and ending with large A and large V wave. If AVNRT could still be induced, the linear lesion region would be moved to the mid level of Koch’s triangle (L2). Results AVNRT could not be induced in 30 and 8 patients after L1 and L2 lesion was finished, respectively. Each linear lesion succeeded with a mean RF deliveries of (4 7±1 1) times (range 3～7 times). There were 5 patients without atrioventricular (AV) junctional beats, and 6 patients with AV junctional beats when large A wave presented in the ablation catheter electrogram during linear ablation procedure. Of all the cases, there were 36 patients had AV conductional jumping phenomena before linear ablation. While there were only 16 patients remained jumping phenomena and 10 of them with single atrial echo after linear ablation. No AV block occurred during linear ablation procedure. And no tachycardia recurred during a mean follow up of (10 4±4 2) months (range 1～18 months). Conclusions Linear lesion at lower or mid level of Koch’s triangle is a safe and effective way in the treatment of the AVNRT for those whose tachycardia are refractory to conventional slow pathway modification. AV junctional beats during RF delivery is not a necessary sign of successful ablation.