Liu Qiang, Shehata Michael, Jiang Ruhong, Yu Lu, Chen Shiquan, Zhu Jun, Ehdaie Ashkan, Sovari Ali A, Cingolani Eugenio, Chugh Sumeet S, Jiang Chenyang, Wang Xunzhang
From the Department of Cardiology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Zhejiang, P.R. China (Q.L., R.J., L.Y., S.C., J.Z., C.J.); and Heart Institute, Cedars Sinai Medical Center, Los Angeles, CA (Q.L., M.S., A.E., A.A.S., E.C., S.S.C., X.W.).
Circ Arrhythm Electrophysiol. 2016 Sep;9(9). doi: 10.1161/CIRCEP.116.004272.
The underlying mechanisms of reentry during left posterior fascicular ventricular tachycardia (LPF-VT) remain unclear. The purpose of this study is to describe the components of LPF-VT reentry circuit and their electrophysiological properties.
Fourteen consecutive patients with LPF-VT underwent electrophysiology study and radiofrequency ablation. Via a multipolar electrode catheter placed from a retrograde aortic approach, a sharp inflection, high-frequency potential (P1) was detected in 9 patients (64%). The ranges of length and velocity of recorded P1 were 9 to 30 mm and 0.5 to 1.2 mm/ms, respectively. Macroreentry involving the ventricular myocardium was confirmed to be the mechanism in all patients by premature ventricular stimuli delivery or entrainment of LPF-VT with progressive fusion, or both. During LPF-VT, the earliest left posterior fascicle (LPF, P2) was considered to be the site of connection between P1 and P2, and the site of the earliest P2 along the left posterior ventricular septum correlated well with the His-ventricular interval during tachycardia. Radiofrequency ablation focused on the P1 potentials (9 patients with a recorded P1) or earliest P2 (5 patients without a recorded P1) was successful in all 14 patients. After 4.5±3.0 months of follow-up, no patients had recurrence of LPF-VT.
The LPF-VT macroreentrant loop involves the ventricular myocardium, a part of the LPF, a slow conduction zone, and in certain cases, a specially conducting P1 fiber. The His-ventricular interval during LPF-VT correlates with multiple electrophysiological measures and is a useful marker for identification of the optimal ablation site.
左后分支性室性心动过速（LPF-VT）折返的潜在机制尚不清楚。本研究的目的是描述LPF-VT折返环路的组成部分及其电生理特性。
14例连续的LPF-VT患者接受了电生理检查和射频消融。通过逆行主动脉途径放置多极电极导管，在9例患者（64%）中检测到一个尖锐的转折、高频电位（P1）。记录到的P1的长度范围为9至30毫米，速度范围为0.5至1.2毫米/毫秒。通过发放室性期前刺激或用逐渐融合的方法拖带LPF-VT，或两者兼用，在所有患者中均证实涉及心室心肌的大折返是其机制。在LPF-VT期间，最早的左后分支（LPF，P2）被认为是P1与P2之间的连接部位，沿着左后室间隔最早的P2部位与心动过速期间的希氏束-心室间期密切相关。针对P1电位（9例记录到P1的患者）或最早的P2（5例未记录到P1的患者）进行射频消融，14例患者均获成功。经过4.5±3.0个月的随访，无患者出现LPF-VT复发。
LPF-VT大折返环涉及心室心肌、LPF的一部分、一个缓慢传导区，在某些情况下还涉及一条特殊传导的P1纤维。LPF-VT期间的希氏束-心室间期与多种电生理指标相关，是识别最佳消融部位的有用标志物。
