Trohman R G, Pinski S L, Sterba R, Schutzman J J, Kleman J M, Kidwell G A
Department of Cardiology, Cleveland Clinic Foundation, OH 44195.
Am Heart J. 1994 Sep;128(3):586-95. doi: 10.1016/0002-8703(94)90635-1.
Our results and those of others (Table I) suggest that both anatomic and electrogram (potential) approaches are highly successful in eliminating AVNRT. The use of slow-pathway potentials appears to minimize lesion delivery and to be associated with a very small likelihood of complete AV block. Approaches aimed directly at the midseptum also appear to reduce lesion delivery. It is important, however, to understand that the fast and slow AV-nodal pathways are not always confined to anterosuperior (fast) and posteroinferior (slow) locations (at least as they are determined fluoroscopically). On occasion, the slow pathway may be ablated anteriorly and the fast pathway posteriorly. Our three inadvertent successful fast-pathway ablations support these findings. We prefer to conceptualize the AV node as having three ablation zones. Ablation in the anterosuperior zone most often affects fast-pathway conduction; ablation in the posteroinferior zone most often affects slow pathway conduction; and ablation in the midseptal region predominantly affects slow-pathway conduction. Lesions applied to the midseptum do, however, appear more likely to affect inadvertently the fast (or both) pathway(s), probably because of the anatomic convergence of the posteroinferior and anterosuperior AV-nodal approaches in this region. A preliminary report by Wu et al. supports this three-zone concept. The subsequent larger series reported by this group has raised concern that midseptal approaches may be associated with too great a risk of complete AV block. On the other hand, approaches guided exclusively by potentials may be associated with much longer procedure times. Controversy exists over the acceptable end point for ablation procedures. We have not found it necessary routinely to eliminate dual-nodal conduction to maintain a low (3.2%) overall recurrence rate. Aggressive attempts to eliminate all evidence of slow-pathway conduction must be balanced against the risk of inadvertent complete AV block. In conclusion, cumulative data and our clinical experience with ablation of AVNRT suggest that it is possible to be both pragmatic and highly successful. The key components of our approach are (1) an anatomically based, systematic, time-limited search for potentials; (2) elimination of unnecessary lesions that are too atrial or too ventricular to involve the reentrant circuit; (3) a caudocephalad approach that avoids excessively anterior initial lesions, which may result in inadvertent complete AV block; and (4) avoidance of unnecessary lesions in the most inferoposterior sector, which results in patient discomfort and low clinical efficacy. This approach is safe (with minimal risk of AV block), reproducible, and efficacious.
我们的研究结果以及其他人的结果（表一）表明，解剖学方法和心内电描记图（电位）方法在消除房室结折返性心动过速方面都非常成功。使用慢径路电位似乎能将消融部位减至最少，且发生完全性房室传导阻滞的可能性非常小。直接针对中隔的方法似乎也能减少消融部位。然而，必须明白，房室结的快径路和慢径路并不总是局限于前上方（快径路）和后下方（慢径路）位置（至少在透视确定的位置上是这样）。有时，慢径路可能在前部被消融，而快径路在后部被消融。我们三次意外成功的快径路消融支持了这些发现。我们倾向于将房室结概念化为有三个消融区。在前上区进行消融最常影响快径路传导；在后下区进行消融最常影响慢径路传导；在中隔区域进行消融主要影响慢径路传导。然而，应用于中隔的消融似乎更有可能意外地影响快径路（或两条径路），可能是因为在该区域后下和前上房室结径路在解剖学上相互靠近。吴等人的一份初步报告支持了这一三区概念。该研究小组随后报告的更大系列研究引起了人们的担忧，即中隔方法可能与完全性房室传导阻滞的风险过高有关。另一方面，仅以电位为导向的方法可能与手术时间长得多有关。关于消融手术可接受的终点存在争议。我们发现没有必要常规消除双结传导来维持较低的（3.2%）总体复发率。积极试图消除慢径路传导的所有证据必须与意外发生完全性房室传导阻滞的风险相权衡。总之，累积数据以及我们对房室结折返性心动过速消融的临床经验表明，既务实又能取得高度成功是可能的。我们方法的关键要素包括：（1）基于解剖学的、系统的、限时的电位搜索；（2）消除过于靠近心房或心室而不涉及折返环路的不必要消融部位；（3）采用尾头方向的方法，避免最初过于靠前的消融部位，这可能导致意外的完全性房室传导阻滞；（4）避免在最靠后下的区域进行不必要的消融，这会导致患者不适且临床疗效不佳。这种方法是安全的（房室传导阻滞风险最小）、可重复的且有效的。
