Pitzalis M V, Luzzi G, Anaclerio M, Rizzon P
Institute of Cardiology, University of Bari, Italy.
Rev Port Cardiol. 1998 Nov;17 Suppl 3:III15-22.
Radiofrequency catheter ablation of accessory pathways may represent the treatment of choice for patients with symptomatic atrio-ventricular reentrant tachycardia or atrial fibrillation and a high ventricular response through the accessory pathways with short antegrade refractory period. Moreover, catheter ablation has contributed towards understanding anatomical and electrophysiological characteristics of accessory pathways. As far as anatomical characteristics accessory pathways may be classified into fibers with proximal insertion in right or left atrium and fibers with proximal insertion in the atrio-ventricular nodal junction. As far as electrophysiological properties are concerned, accessory pathways may be differentiated into non-decremental and decremental. In non-decremental by-pass tracts (the so-called Kent bundles) the impulse can be conducted antegradely, retrogradely and in both directions. Decremental accessory pathways generally show only antegrade conduction properties (the so-called Mahaim fibers) and can be classified in long and short pathways; in particular, catheter ablation has given considerable evidence that the vast majority (but not all) of them has a proximal insertion on the tricuspid anulus (atrio-ventricular pathways) or on the atrio-ventricular node (nodo-ventricular pathways). Decremental accessory pathways with only retrograde conduction properties are involved in the so called "Permanent Junctional Reciprocating Reentrant Tachycardia".
对于有症状的房室折返性心动过速或心房颤动且经旁道有快速心室反应及短前传不应期的患者，射频导管消融旁道可能是首选治疗方法。此外，导管消融有助于了解旁道的解剖和电生理特征。就解剖特征而言，旁道可分为近端插入右心房或左心房的纤维以及近端插入房室结连接处的纤维。就电生理特性而言，旁道可分为非递减性和递减性。在非递减性旁道（所谓的肯特束）中，冲动可向前、向后及双向传导。递减性旁道通常仅表现出前向传导特性（所谓的Mahaim纤维），可分为长旁道和短旁道；特别是，导管消融已提供了大量证据表明，其中绝大多数（但并非全部）在三尖瓣环（房室旁道）或房室结（结室旁道）有近端插入。仅具有逆向传导特性的递减性旁道参与所谓的“永久性交界性反复性心动过速”。
