射频消融慢径后心动过速复发与房室结电生理特性变化的关系

为揭示房室结折返性心动过速（ＡＶＮＲＴ）复发的机制，对４５例射频消融治疗成功的慢－快型ＡＶＮＲＴ患者在消融术前、术后即刻及术后逾三个月行电生理检查。结果１０例复发（复发组）。复发组术前心房早搏刺激时的最大心房－Ｈｉｓ束间期（Ａ２Ｈ２ｍａｘ）较非复发组明显延长（４１３±６０ｍｓｖｓ３１１±１１０ｍｓ，Ｐ＜０．０１）；两组术后即刻Ａ２Ｈ２ｍａｘ较术前均明显缩短（Ｐ均＜０．０１）；术后三个月复发组的Ａ２Ｈ２ｍａｘ较术后即刻明显延长（３５６±９３ｍｓｖｓ２９８±９６ｍｓ，Ｐ＜０．０５），非复发组则有进一步缩短趋势，两组术后三个月的Ａ２Ｈ２ｍａｘ比较有显著性差异（３５６±９３ｍｓｖｓ２２２±７３ｍｓ，Ｐ＜０．００５）；非复发组术后三个月Ａ２Ｈ２ｍａｘ较术前明显缩短（２２２±７３ｍｓｖｓ３１１±１１０ｍｓ，Ｐ＜０．０１），房室结前传文氏周期及有效不应期较术前明显延长（４０５±９１ｍｓｖｓ３６６±８４ｍｓ，３３２±７５ｍｓｖｓ２６９±６３ｍｓ，Ｐ＜０．０１及＜０．０００１），复发组消融术前后比较差异则无显著性。结果提示部分ＡＶＮＲＴ复发可能与其房室结本身电生理特性有关，基础状态下Ａ２Ｈ２ｍａｘ长的患者心动过速更易复发。

Atrioventricular Nodal Electrophysiologic Properties in Patients With Atrioventricular Nodal Reentrant Tachycardia Before and After Slow Pathway Ablation and Their Relationships to Tachycardia Recurrences

Forty five patients with the common form of atrioventricular (AV) nodal reentrant tachycardia(AVNRT) who underwent initial successful slow pathway ablation and later electrophysiologic study (EPS) were studied.It consisted of 10 patients with and 35 patients without tachycardia recurrence.The mean maximal atrial His interval(A2H2max) measured during premature atrial stimulation before ablation was significantly longer in patients with tachycardia recurrence (P<0.01).Immediately after ablation,A2H2max was significantly shorter than control value both in patients with and without tachycardia recurrence (P<0.01).During follow up EPS,the mean A2H2max increased significantly from 298±96 ms immediately after ablation to 356±93 ms in patients with recurrence (P<0.05).In contrast,it did not change significantly in patients without recurrence.Thus,the difference in A2H2max at the follow up was significantly different between the two groups (P<0.005).In patients without recurrence,A2H2max significantly decreased from 311±110 ms before ablation to 222±73 ms during follow up (P<0.01).AV nodal anterograde Wenckebach cycle length and effective refractory period of AV node significantly increased (P<0.01).However,the change of these parameters was not significant in patients with tachycardia recurrence.