Silka M J, Kron J, Halperin B D, Griffith K, Crandall B, Oliver R P, Walance C G, McAnulty J H
Department of Pediatrics, Oregon Health Sciences University, Portland 97201-3908.
Pacing Clin Electrophysiol. 1992 Jul;15(7):1000-7. doi: 10.1111/j.1540-8159.1992.tb03093.x.
Due to the limited myocardial lesions produced by radiofrequency current, the ablation of accessory pathways (AP) requires precise localization of such connections. The purpose of this study was to ascertain which characteristic(s) of the local bipolar electrogram, recorded from the ablation and adjacent electrode immediately prior to the application of radiofrequency current, correlated with precision in localization adequate to permit AP ablation. Signal analysis was performed for 326 sets of electrograms preceding the attempted ablation of 107 APs in 100 consecutive patients. For 80 antegrade APs, the following variables were evaluated: (1) the presence or absence of an AP potential; (2) the local atrial-AP interval; (3) the local atrioventricular (AV) interval; and (4) the relationship between the onset of local ventricular depolarization and onset of delta wave of the surface electrocardiogram. For the 27 concealed APs, the following characteristics were evaluated: (1) the presence or absence of an AP potential; and (2) the local VA interval during reciprocating tachycardia or ventricular pacing.
Antegrade APs: By statistical analysis, the best correlate of successful ablation of an antegrade AP was a local AV interval less than or equal to 40 msec (positive predictive value = 94%; 95% confidence intervals [CI] = 81%-100%). Local AV intervals less than or equal to 50 msec preceded 88% of successful AP ablations, compared to only 8% of failed radiofrequency current applications. The positive predictive value of the other variables were: presence of an AP potential: 35% (95% CI = 27%-40%); local atrial-AP intervals less than or equal to 40 msec: 54% (95% CI = 43%-66%); and local ventricular depolarization preceding onset of the delta wave 43% (95% CI = 34%-52%). For concealed APs, the positive predictive value of a VA interval less than 60 msec was 71% (95% CI = 48%-88%); the positive predictive value for the presence of an AP potential was 58% (95% CI = 32%-81%).
No single electrogram characteristic had a positive predictive value and a sensitivity greater than 90% for AP localization adequate for radiofrequency current ablation. For antegrade APs, the best correlate of adequate localization was a local AV interval less than or equal to 40 msec; as a corollary, radiofrequency current applications at sites where the local AV was greater than 60 msec, were unlikely to be effective. Objective criteria for the localization of concealed APs were less certain. Electrogram analysis, as a guide to AP localization and ablation, requires careful analysis of multiple variables, with analysis of the local AV interval a salient objective factor.
由于射频电流产生的心肌损伤有限，消融旁路（AP）需要精确确定此类连接的位置。本研究的目的是确定在施加射频电流之前立即从消融电极和相邻电极记录的局部双极电图的哪些特征与足以允许消融AP的定位精度相关。对连续100例患者中107条AP尝试消融前的326套电图进行了信号分析。对于80条顺行AP，评估了以下变量：（1）AP电位的有无；（2）局部心房-AP间期；（3）局部房室（AV）间期；（4）局部心室去极化起始与体表心电图δ波起始之间的关系。对于27条隐匿性AP，评估了以下特征：（1）AP电位的有无；（2）折返性心动过速或心室起搏期间的局部VA间期。
顺行AP：通过统计分析，成功消融顺行AP的最佳相关因素是局部AV间期小于或等于40毫秒（阳性预测值=94%；95%置信区间[CI]=81%-100%）。局部AV间期小于或等于50毫秒出现在88%的成功AP消融之前，而在失败的射频电流应用中仅占8%。其他变量的阳性预测值为：AP电位的存在：35%（95%CI=27%-40%）；局部心房-AP间期小于或等于40毫秒：54%（95%CI=43%-66%）；局部心室去极化先于δ波起始：43%（95%CI=34%-52%）。对于隐匿性AP，VA间期小于60毫秒的阳性预测值为71%（95%CI=48%-88%）；AP电位存在的阳性预测值为58%（95%CI=32%-81%）。
对于足以进行射频电流消融的AP定位，没有单一的电图特征具有大于90%的阳性预测值和敏感性。对于顺行AP，充分定位的最佳相关因素是局部AV间期小于或等于40毫秒；因此，在局部AV大于60毫秒的部位应用射频电流不太可能有效。隐匿性AP定位的客观标准不太确定。电图分析作为AP定位和消融的指导，需要仔细分析多个变量，其中局部AV间期的分析是一个突出的客观因素。
