Aizawa Y, Satoh M, Shibata A, Josephson M E
First Department of Internal Medicine, Niigata University School of Medicine, Japan.
Pacing Clin Electrophysiol. 1989 Apr;12(4 Pt 1):563-8. doi: 10.1111/j.1540-8159.1989.tb02701.x.
In cases of recurrent sustained ventricular tachycardia (VT), constant fusion and progressive fusion in the surface electrogram were observed during overdrive pacing of VT. However, following cessation of pacing, the return cycle of VT (stimulus to the first nonpaced QRS) was longer than the VT cycle length. This phenomenon can be explained by orthodromic capture of the exit site of the VT current with a conduction time (stimulus to QRS) exceeding the VT cycle length. This site can therefore be activated during entrainment of VT during the mid-to-terminal portion of the paced QRS complex, resulting in constant fusion.
在复发性持续性室性心动过速（VT）的病例中，在VT的超速起搏期间，体表心电图中观察到持续融合和进行性融合。然而，起搏停止后，VT的回归周期（刺激至第一个非起搏QRS波）长于VT周期长度。这种现象可以通过VT电流出口部位的顺向夺获来解释，其传导时间（刺激至QRS波）超过VT周期长度。因此，在起搏QRS波群的中末段VT夺获期间，该部位可被激活，导致持续融合。
