房束旁道的电生理特点与Mahaim电位在射频导管消融中的意义

探讨房束旁道的电生理特点与Mahaim电位在射频导管消融 (RFCA)中的意义。 1997年 7月至 2 0 0 3年 1月对 3例拟诊为房束旁道引起的逆向型房室折返性心动过速的患者进行了电生理检查和RFCA。男 2例 ,女 1例 ,年龄分别为 18,2 3,2 5岁。心动过速发作史 7～ 16年 ,频率 180～ 2 30次 /分 ,发作时均有明显心悸 ,其中 1例伴头晕、胸闷。窦性心律时心电图 1例正常 ,另 2例示轻微预激。食管心房调搏与心房程序刺激均易诱发心动过速 ,心动过速时体表心电图呈宽QRS波形。 3例均在三尖瓣环右后侧壁标测到的Mahaim电位处 ,于窦性心律及心房起搏下放电消融。 2例彻底阻断旁道前向传导 ,另 1例反复放电未阻断旁道 ,但重复术前程序刺激心动过速不再诱发。分别随访 5年、2年、6个月心动过速均未复发。结论 :RFCA治疗房束旁道介导的心动过速安全有效 ,Mahaim电位在RFCA中具有重要指导价值。

Electrophysiological Characteristics of Atriofascicular Accessory Pathway and Significance of Mahaim Potentials in Radiofrequency Catheter Ablation

To investigate the electrophysiological characteristics of atriofascicular accessory pathway and significance of Mahaim potentials in radiofrequency catheter ablation. Three patients (two male and one female, 18 to 25 years old) who were diagnosed antidromic atrioventricular reciprocating tachycardia attributed to atriofascicular pathways, were performed electrophysiological study and radiofrequency catheter ablation, with tachycardia history for 7 to 16 years, heart rate 180 to 230 beats/minute.All the three patients felt palpitation while tachycardia appeared, and one of them felt dizziness and chest press.One electrocardiogram(ECG) was normal, the other two showed little preexcitation. Esophagal pacing and atrial stimulation could easily induced tachycardia, and their ECG showed wide QRS waves. The three patients were mapped Mahaim potentials and were ablated in right posterior lateral of trcuspid valve ring during sinus rhythm and atrial pacing. The atriofascicular pathway of two cases were completely ablated, and the other pathway were not ablated, but tachycardia could not be induced. Respectively following up for 5 years,2 years,6 months, no tachycardia reccurred. Conclusion: It is effective and safe to ablate atriofascicular pathway with radiofrequency, Mahaim potential is an important mark to ablate atriofascicular pathway.