Haissaguerre M, Gaita F, Fischer B, Commenges D, Montserrat P, d'Ivernois C, Lemetayer P, Warin J F
Service de Cardiologie, Hôpital Saint-André, Bordeaux, France.
Circulation. 1992 Jun;85(6):2162-75. doi: 10.1161/01.cir.85.6.2162.
Ablation of the slow pathway has been performed to eliminate atrioventricular (AV) nodal reentrant tachycardia (AVNRT) either by a surgical approach or by using radiofrequency catheter technique guided by retrograde slow pathway activation mapping. From previous experience of midseptal and posteroseptal mapping, we were aware of the existence of peculiar slow potentials in most humans. Postulating their role in AVNRT, we studied these potentials and the effects of radiofrequency energy.
Sixty-four patients (mean age, 48 +/- 19 years) with the usual form of AVNRT were studied. Slow, low-amplitude potentials were recorded when using the anterograde AV conducting system. Slow potentials occupied all (giving a continuum of electrograms) or some of the time between the atrial and ventricular electrograms. Their most specific patterns were their progressive response to increasing atrial rates, which resulted in a dramatic decline in amplitude and slope, a corresponding increase in duration, and a separation from preceding atrial potentials until the disappearance of any consistent activity. Slow potentials were recorded along a vertical band at the mid or posterior part of the septum near the tricuspid annulus. Radiofrequency energy applied at the slow potential site resulted in interruption of induced tachycardia within a few seconds and rendered tachycardia noninducible in all patients. A median of two impulses was delivered to each patient. In 69% of patients, postablation atrial stimulation cannot achieve a long atrial-His interval, which previously was critical for tachycardia induction or maintenance. No patient had AVNRT over a follow-up period of 1-16 months, and all had preserved AV conduction. In all except two patients, the PR interval was unchanged. In 47 patients, long-term electrophysiological studies confirmed the efficacy of ablation and the nonreversibility of results by isoproterenol; however, echo beats remained inducible in 40% of patients.
An area showing slow potentials is present at the perinodal region in humans. In patients with AVNRT, application of radiofrequency energy renders tachycardia noninducible through the preferential modification of the anterograde slow pathway. With present clinical methods, the exact origin and significance of these physiological potentials cannot be specified.
已通过手术方法或采用由逆行慢径激活标测引导的射频导管技术来消融慢径，以消除房室结折返性心动过速（AVNRT）。根据先前对中隔和后隔标测的经验，我们意识到大多数人存在特殊的慢电位。鉴于其在AVNRT中的作用，我们研究了这些电位以及射频能量的影响。
对64例（平均年龄48±19岁）典型形式的AVNRT患者进行了研究。使用顺行房室传导系统时记录到缓慢、低振幅电位。慢电位占据心房和心室电图之间的全部时间（形成连续的电图）或部分时间。其最具特征性的模式是对心房率增加的渐进性反应，这导致振幅和斜率急剧下降、持续时间相应增加，并与先前的心房电位分离，直至任何持续活动消失。慢电位沿靠近三尖瓣环的中隔或后隔中部的垂直带记录。在慢电位部位施加射频能量可在数秒内中断诱发的心动过速，并使所有患者的心动过速不能被诱发。每位患者平均给予两次脉冲。69%的患者在消融后心房刺激不能达到长的心房 - 希氏间期，而这之前对心动过速的诱发或维持至关重要。在1至16个月的随访期内，无患者发生AVNRT，且所有患者的房室传导均得以保留。除两名患者外，所有患者的PR间期均未改变。在47例患者中，长期电生理研究证实了消融的有效性以及异丙肾上腺素对结果的不可逆性；然而，40%的患者仍可诱发回波搏动。
在人类的结周区域存在显示慢电位的区域。在AVNRT患者中，应用射频能量通过优先改变顺行慢径使心动过速不能被诱发。采用目前的临床方法，无法明确这些生理电位的确切起源和意义。
