Yamashita T, Murakawa Y, Ajiki K, Omata M
Second Department of Internal Medicine, Faculty of Medicine, University of Tokyo, Japan.
Circulation. 1997 Feb 4;95(3):650-4. doi: 10.1161/01.cir.95.3.650.
Atrial fibrillation/flutter (Af) has been considered to occur coincidentally with atrioventricular (AV) block. However, a case with complete AV block was reported to histologically show fibrotic changes solely in the atrial muscles but neither in the AV node nor in the His bundle, indicating a possible relation between AV block and atrial tachyarrhythmias. To test a hypothesis that AV block and Af are causally interrelated, we investigated the incidence and electrophysiological characteristics of Af in complete AV block.
Forty-two patients with persistent complete AV block underwent the electrophysiological study. Patients with spontaneous/electrically induced Af were compared with the other patients with respect to their electrophysiological variables. Of the 42 patients, Af was transiently induced by electrical stimulation in 5 patients (11.9%), while persistent Af was observed in 2 patients (4.8%, AH and HV block). AV block in the 5 patients with induced Af was invariably due to AH block. AH block complicated by persistent/induced Af was marked by relatively short RR intervals, significantly short junctional recovery time, and impaired intra-atrial conduction.
Electrically induced Af in complete AV block was associated frequently with complete AH block. These patients were characterized differently from the commonly recognized AV block and therefore may stand as a unique subgroup of AH block.
心房颤动/扑动（Af）一直被认为与房室（AV）阻滞同时发生。然而，有报道称一例完全性AV阻滞患者的组织学检查显示仅心房肌有纤维化改变，而房室结和希氏束无改变，提示AV阻滞与房性快速性心律失常之间可能存在关联。为验证AV阻滞与Af存在因果关系这一假说，我们研究了完全性AV阻滞患者中Af的发生率及电生理特征。
42例持续性完全性AV阻滞患者接受了电生理检查。将自发/电诱发Af的患者与其他患者的电生理变量进行比较。42例患者中，5例（11.9%）经电刺激短暂诱发Af，2例（4.8%，AH和HV阻滞）观察到持续性Af。5例诱发Af患者的AV阻滞均为AH阻滞。伴有持续性/诱发性Af的AH阻滞表现为RR间期相对较短、交界区恢复时间明显缩短及心房内传导受损。
完全性AV阻滞中电诱发的Af常与完全性AH阻滞相关。这些患者与公认的AV阻滞特征不同，因此可能是AH阻滞的一个独特亚组。
