Xie B, Heald S C, Camm A J, Rowland E, Ward D E
Department of Cardiological Sciences, St. George's Hospital Medical School, London, U.K.
Eur Heart J. 1996 Jul;17(7):1072-9. doi: 10.1093/oxfordjournals.eurheartj.a015004.
Successful ablation of accessory pathways has been achieved at the first energy delivery site in some patients, but factors permitting success at the first site are unclear. Accessory pathway location, surface and endocardial electrogram characteristics in each location were analysed and compared between the patients with first site block (group A, 34 patients) and those in whom multiple sites (median seven sites) were required (group B, 133 patients). No patients with right free-wall pathways had first site block. In group A surface electrocardiograms were more pre-excited (QRS duration: 132 +/- 20 vs 120 +/- 17 ms, P < 0.01). For left free-wall and septal pathways, the interval from the onset of the earliest delta wave on surface electrocardiogram to local ventricular activation (QRS-V) was more negative and the local atrioventricular interval (AV) was shorter in group A; the positive predictive value of a QRS-V < or = 0 ms, an AV < or = 30 ms and the presence of a possible accessory pathway potential was 67% for left free-wall and of a QRS-V < or = -10 ms with an AV < or = 30 ms was 100% for septal pathways. During retrograde mapping of concealed left free-wall and right anteroseptal pathways (first site block was not achieved in other locations) the positive predictive value of a local ventriculoatrial interval < or = 30 ms was 55%. Accessory pathway location correlated strongly with the chances of first site block, suggesting that anatomical features are important. Maximizing pre-excitation may be of benefit in achieving first site block. Delivery of energy to a site with special endocardial electrogram features was associated with an increased likelihood of first site block.
在一些患者中，首次能量释放部位成功实现了旁路消融，但首次部位成功的相关因素尚不清楚。分析并比较了首次部位阻滞患者（A组，34例）和需要多个部位（中位数为7个部位）的患者（B组，133例）的旁路位置、各位置的体表和心内膜心电图特征。右游离壁旁路患者无一例首次部位阻滞。A组体表心电图预激程度更高（QRS时限：132±20 vs 120±17 ms，P<0.01）。对于左游离壁和间隔旁路，A组中体表心电图最早δ波起始至局部心室激动的间期（QRS-V）更负，局部房室间期（AV）更短；对于左游离壁旁路，QRS-V≤0 ms、AV≤30 ms以及存在可能的旁路电位的阳性预测值为67%，对于间隔旁路，QRS-V≤-10 ms且AV≤30 ms的阳性预测值为100%。在隐匿性左游离壁和右前间隔旁路的逆行标测过程中（其他部位未实现首次部位阻滞），局部室房间期≤30 ms的阳性预测值为55%。旁路位置与首次部位阻滞的可能性密切相关，提示解剖特征很重要。最大化预激可能有助于实现首次部位阻滞。向具有特殊心内膜心电图特征的部位释放能量与首次部位阻滞的可能性增加相关。
