Haissaguerre M, Warin J F, Le Metayer P, Maraud L, De Roy L, Montserrat P, Massiere J P
Service de Cardiologie et Médecine Interne, Hopital Saint-André, Bordeaux, France.
Circulation. 1990 Aug;82(2):418-27. doi: 10.1161/01.cir.82.2.418.
Three patients with refractory preexcited tachycardia implicating Mahaim fibers underwent attempted catheter ablation of the accessory pathway. In the absence of demonstrable retrograde conduction in Mahaim fibers, we located the accessory pathway ventricular insertion site using the criteria of concordance between paced and spontaneous QRS morphologies during pace-mapping and earliest onset of local electrogram relative to surface preexcited QRS. At this site, a QS-like pattern of unfiltered unipolar electrograms with steep downstroke was recorded. The optimal site appeared radiologically at the right ventricular anterior wall or the adjacent septum, 2-4 cm from the tricuspid anulus. Three to six 160-J shocks were delivered at this site using an anterior chest wall plate as anode. After fulguration, conduction through the Mahaim tract was absent. A right bundle branch block persisted in two patients. All patients remained free of preexcited tachycardia during 12-16 months of follow-up. Postablation electrophysiological assessment showed no preexcitation in any patient. No reciprocating tachycardia was inducible, even during isoproterenol infusion. Atrioventricular nodal conduction parameters were unchanged from baseline study. Catheter ablation of Mahaim fibers is an effective alternative method for the treatment of tachycardias that include the accessory pathway in the circuit.
三名患有涉及Mahaim纤维的难治性预激性心动过速的患者接受了旁路导管消融术。在Mahaim纤维中未发现可证实的逆向传导的情况下，我们使用起搏标测期间起搏和自发QRS形态的一致性标准以及相对于体表预激QRS的局部电图最早起始点来定位旁路心室插入部位。在该部位，记录到具有陡峭下降支的未滤波单极电图的QS样图形。最佳部位在影像学上表现为右心室前壁或相邻间隔，距三尖瓣环2-4厘米。使用前胸壁板作为阳极在该部位施加3至6次160焦耳的电击。电灼后，通过Mahaim束的传导消失。两名患者持续存在右束支传导阻滞。在12至16个月的随访期间，所有患者均未出现预激性心动过速。消融后电生理评估显示任何患者均无预激。即使在输注异丙肾上腺素期间，也不能诱发折返性心动过速。房室结传导参数与基线研究相比未发生变化。Mahaim纤维的导管消融是治疗包括旁路在内的心动过速的一种有效替代方法。
