Prakash A, Saksena S, Krol R B, Philip G
Arrhythmia & Pacemaker Service, Cardiovascular Institute-Atlantic Health System, Passaic, Milburn, NJ 07041, USA.
Am J Cardiol. 2001 May 1;87(9):1080-8. doi: 10.1016/s0002-9149(01)01465-5.
We examined the regional electrophysiologic effects of successful and unsuccessful direct-current cardioversion shocks on different right and left atrial regions in patients with sustained atrial fibrillation (AF). Patients with sustained AF undergoing external cardioversion underwent simultaneous mapping of the right and left atria. Electrogram changes after shock delivery, regional atrial activation, and effects of shock intensity were analyzed. Twenty-two patients with sustained AF received 52 shocks (mean 2.4/patient, 22 successful and 30 unsuccessful). The efficacy of 50, 100, 200, and 300 J was 18%, 39%, 100%, and 100%, respectively. In all 22 successful shocks, there was virtually simultaneous termination of electrical activity in all right and left atrial regions mapped. Unsuccessful shocks resulted in a significant increase in mean atrial cycle length at lateral right atrium, superior left atrium, and proximal, mid, and distal coronary sinus (p = 0.01), but not at the interatrial septum (p >0.2), which often disappeared before the next shock. This cycle length prolongation was accompanied by reduction in fragmented and chaotic electrograms (p <0.03) and emergence of discrete electrograms at all right and left atrial regions that persisted until the next shock. The changes in electrogram morphology failed to alter the surface electrocardiographic appearance of AF. There was no correlation between the shock intensity and the magnitude of these effects. We conclude that termination of AF with external cardioversion shocks is associated with the widespread extinction of regional atrial wave fronts. Unsuccessful shocks are associated with a temporary slowing of atrial activation at all regions except at the interatrial septum and emergence of organized and/or rapidly propagating wave fronts.
我们研究了成功与失败的直流电复律电击对持续性心房颤动（AF）患者不同右心房和左心房区域的局部电生理效应。接受体外复律的持续性AF患者同时进行右心房和左心房标测。分析电击后心电图变化、局部心房激动及电击强度的影响。22例持续性AF患者接受了52次电击（平均每人2.4次，22次成功，30次失败）。50、100、200和300焦耳的复律成功率分别为18%、39%、100%和100%。在所有22次成功的电击复律中，几乎所有标测的右心房和左心房区域的电活动同时终止。失败的电击导致右心房外侧、左心房上部以及冠状窦近端、中部和远端的平均心房周期长度显著增加（p = 0.01），但在房间隔处未增加（p > 0.2），且这种增加通常在下一次电击前消失。这种周期长度的延长伴随着碎裂和紊乱心电图的减少（p < 0.03），以及所有右心房和左心房区域出现离散的心电图，且持续到下一次电击。心电图形态的改变并未改变AF的体表心电图表现。电击强度与这些效应的大小之间无相关性。我们得出结论，体外电击复律终止AF与局部心房波前的广泛消失有关。失败的电击与除房间隔外所有区域的心房激动暂时减慢以及有组织和/或快速传播的波前出现有关。
