Sato M, Sakurai M, Yotsukura A, Betsuyaku T, Ito T, Yoshida I, Kitabatake A
Department of Cardiovascular Medicine, Hokkaido University, School of Medicine, Kitaku, Sapporo, Japan.
Am Heart J. 1999 Sep;138(3 Pt 1):560-6. doi: 10.1016/s0002-8703(99)70161-4.
Diastolic potentials (DP) are reported to be recorded in intracardiac electrograms during verapamil-sensitive ventricular tachycardia (VT) in which QRS complexes show complete right bundle branch block with a superior axis. The purpose of this study was to ascertain whether the DP recorded in the endocardial mapping during VT reflects the activation of the VT circuit.
The study group consisted of 16 men and 2 women. The earliest activation site (EA site) was determined and the DP was recorded in the endocardial mapping during VT. We evaluated the response of the cycle length of VT, the interval between the ventricular activation and the DP (V-DP), and the interval between the DP and the ventricular activation (DP-V) to intravenous verapamil. Radiofrequency current was delivered to the EA site, the site where the DP was recorded, and the site where the DP and the Purkinje fiber potential of the left bundle branch (LB) were simultaneously recorded. In 15 patients, the DP was recorded in the wide posterior fascicle region of the LB. After verapamil, the cycle length of VT, the V-DP, and the DP-V were prolonged from 365 +/- 53 to 490 +/- 65, 315 +/- 30 to 368 +/- 30, and 50 +/- 27 to 123 +/- 36 ms, respectively, in 6 patients. The LB was recorded in all patients and the DP was recorded preceding the LB in 12 patients. VT was successfully ablated at the site where the DP and the LB were simultaneously recorded in all these patients. Ablation at the other sites failed.
Radiofrequency ablation at the site where the DP was simultaneously recorded preceding the LB completely abolished the verapamil-sensitive VT. The DP recorded with the LB simultaneously might reflect the slow conduction zone activity of the reentry circuit located within the Purkinje fiber network.
据报道，在维拉帕米敏感的室性心动过速（VT）的心内电图中可记录到舒张期电位（DP），其中QRS波群表现为完全性右束支传导阻滞伴电轴上偏。本研究的目的是确定VT期间心内膜标测中记录的DP是否反映VT环路的激活。
研究组包括16名男性和2名女性。确定最早激动部位（EA部位）并在VT期间的心内膜标测中记录DP。我们评估了静脉注射维拉帕米后VT的周期长度、心室激动与DP之间的间期（V-DP）以及DP与心室激动之间的间期（DP-V）的反应。将射频电流施加到EA部位、记录DP的部位以及同时记录DP和左束支（LB）浦肯野纤维电位的部位。15例患者中，DP记录于LB的宽后分支区域。维拉帕米给药后，6例患者的VT周期长度、V-DP和DP-V分别从365±53延长至490±65、315±30延长至368±30、50±27延长至123±36 ms。所有患者均记录到LB，12例患者中DP先于LB记录。在所有这些患者中，在同时记录到DP和LB的部位成功消融VT。在其他部位消融失败。
在LB之前同时记录到DP的部位进行射频消融可完全消除维拉帕米敏感的VT。与LB同时记录到的DP可能反映了位于浦肯野纤维网络内的折返环路的缓慢传导区活动。
