Jackman W M, Beckman K J, McClelland J H, Wang X, Friday K J, Roman C A, Moulton K P, Twidale N, Hazlitt H A, Prior M I
Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City 73190.
N Engl J Med. 1992 Jul 30;327(5):313-8. doi: 10.1056/NEJM199207303270504.
Atrioventricular nodal reentrant tachycardia (AVNRT), the most common form of supraventricular tachycardia, results from conduction through a reentrant circuit comprising fast and slow atrioventricular nodal pathways. Antiarrhythmic-drug therapy is not consistently successful in controlling this rhythm disturbance. Catheter ablation of the fast pathway with radiofrequency current eliminates AVNRT, but it can produce heart block. We hypothesized that catheter ablation of the site of insertion of the slow pathway into the atrium would eliminate AVNRT while leaving normal (fast-pathway) atrioventricular nodal conduction intact.
Eighty patients with symptomatic AVNRT were studied. Retrograde slow-pathway conduction (in which the earliest retrograde atrial potential was recorded at the posterior septum, close to the coronary sinus) was present in 33 patients. The retrograde atrial potential was preceded by a potential consistent with activation of the atrial end of the slow pathway (ASP). In 46 of the 47 patients without retrograde slow-pathway conduction, a potential with the same characteristics as the ASP potential was recorded during sinus rhythm. Radiofrequency current delivered through a catheter to the ASP site (in the posteroseptal right atrium or coronary sinus) abolished or modified slow-pathway conduction in 78 patients, eliminating AVNRT without affecting normal atrioventricular nodal conduction. In the single patient without ASP, the application of radiofrequency current to the proximal coronary sinus ablated the fast pathway and AVNRT: Atrioventricular block occurred in one patient (1.3 percent) with left bundle-branch block, after inadvertent ablation of the right bundle branch. AVNRT has not recurred in any patient during a mean (+/- SD) follow-up of 15.5 +/- 11.3 months. Electrophysiologic study 4.3 +/- 3.3 months after ablation in 32 patients demonstrated normal atrioventricular nodal conduction without AVNRT:
Catheter ablation of the atrial end of the slow pathway using radiofrequency current, guided by ASP potentials, can eliminate AVNRT with very little risk of atrioventricular block.
房室结折返性心动过速（AVNRT）是室上性心动过速最常见的形式，由通过包含快、慢房室结径路的折返环传导引起。抗心律失常药物治疗在控制这种节律紊乱方面并非始终成功。用射频电流导管消融快径路可消除AVNRT，但可能导致心脏传导阻滞。我们推测，导管消融慢径路心房插入部位可消除AVNRT，同时保持正常（快径路）房室结传导完整。
对80例有症状的AVNRT患者进行了研究。33例患者存在逆向慢径路传导（最早的逆向心房电位记录于后间隔，靠近冠状窦）。逆向心房电位之前有一个与慢径路心房端激活一致的电位（ASP）。在47例无逆向慢径路传导的患者中，46例在窦性心律时记录到了与ASP电位特征相同的电位。通过导管将射频电流施加于ASP部位（后间隔右心房或冠状窦），使78例患者的慢径路传导被消除或改变，消除了AVNRT，且未影响正常房室结传导。在唯一一例无ASP的患者中，将射频电流施加于冠状窦近端消融了快径路和AVNRT：1例左束支传导阻滞患者在无意中消融右束支后发生了房室传导阻滞（1.3%）。在平均（±标准差）15.5±11.3个月的随访期间，所有患者的AVNRT均未复发。32例患者在消融后4.3±3.3个月进行的电生理研究显示，房室结传导正常，无AVNRT：
在ASP电位引导下，用射频电流导管消融慢径路心房端可消除AVNRT，发生房室传导阻滞的风险极小。
