Zima Endre, Gergely Mihály, Soós Pál, Gellér László Alajos, Nemes Attila, Acsády György, Merkely Béla
Cardiovascular Center, Department of Cardiovascular Surgery, Semmelweis University, 68 Városmajor Str., H-1122 Budapest, Hungary.
J Cardiovasc Electrophysiol. 2006 Apr;17(4):377-81. doi: 10.1111/j.1540-8167.2006.00352.x.
Since no clinical data are available on the comparison of the "shock on T-wave" and "high frequency burst" ventricular fibrillation (VF) induction modes during defibrillation threshold (DFT) testing, we aimed to compare these two methods during implantable cardioverter defibrillator implantation.
The DFT was determined with a step-down protocol using biphasic, anodal polarity (100%, 40%, 20% voltage control) shocks. Patients were randomized: VF was induced by 50 Hz burst in group B (n = 45) and T-wave shock in group T (n = 41). The DFT was defined as the lowest energy level that terminated VF; confirmed DFT (DFTc) was defined as the minimal energy level that consecutively terminated VF twice. Success rate of DFTc was calculated during an intraindividual test for the alternate induction method.
A total of 546 episodes of VF were induced: n = 278 (B) vs n = 268 (T). Incidence of VT during inductions was 9.9% (B) vs 2.7% (T), P < 0.05. Neither the DFT, 8.8 +/- 4.0 J (B) vs 9.7 +/- 4.2 J (T), nor the DFTc, 10.6 +/- 5.1 J (B) vs 10.8 +/- 4.2 J (T), proved to be significantly different. A significant correlation was found between VF cycle length (CL) and the concomitant DFT (r = 0.298, P < 0.05) in group T only. Subgroup analysis of patients under chronic class III antiarrhythmic treatment showed no increase of the DFT in either group and significantly lower incidence of VT induction in group T regardless of antiarrhythmic treatment.
The DFT and the VFCL proved to be independent of the VF induction method. The T-wave shock was more unlikely to induce VT during DFT testing. These results suggest that both methods are reliable in DFT determination, though T-wave shock application is a more reliable method for DFT testing.
由于在除颤阈值（DFT）测试期间，尚无关于“T波上电击”和“高频猝发”心室颤动（VF）诱发模式比较的临床数据，我们旨在比较在植入式心律转复除颤器植入过程中的这两种方法。
采用双相、阳极极性（100%、40%、20%电压控制）电击的递减方案测定DFT。患者被随机分组：B组（n = 45）采用50 Hz猝发诱发VF，T组（n = 41）采用T波电击诱发VF。DFT定义为终止VF的最低能量水平；确认的DFT（DFTc）定义为连续两次终止VF的最小能量水平。在个体内测试交替诱发方法期间计算DFTc成功率。
共诱发546次VF发作：n = 278（B组）对n = 268（T组）。诱发期间室性心动过速（VT）的发生率为9.9%（B组）对2.7%（T组），P < 0.05。DFT（8.8±4.0 J（B组）对9.7±4.2 J（T组））和DFTc（10.6±5.1 J（B组）对10.8±4.2 J（T组））均无显著差异。仅在T组中发现VF周期长度（CL）与伴随的DFT之间存在显著相关性（r = 0.298，P < 0.05）。对接受慢性III类抗心律失常治疗的患者进行亚组分析显示，两组的DFT均未增加，且无论抗心律失常治疗如何，T组诱发VT的发生率显著降低。
DFT和VFCL被证明与VF诱发方法无关。在DFT测试期间，T波电击诱发VT的可能性较小。这些结果表明，两种方法在DFT测定中都是可靠的，尽管应用T波电击是一种更可靠的DFT测试方法。
