Ellenbogen K A, Rogers R, Old W
Department of Medicine, Medical College of Virginia, Richmond.
Pacing Clin Electrophysiol. 1989 Aug;12(8):1396-404. doi: 10.1111/j.1540-8159.1989.tb05054.x.
The presence of a nodoventricular pathway (Mahaim fiber) has been invoked to explain certain distinctive electrocardiographic and electrophysiological observations. The presence of an atrioventricular or atriofascicular fiber with decremental conduction properties has been documented in many of these patients. We report the case of a patient with a Mahaim fiber and the response to conduction over this pathway after adenosine, procainamide, encainide, verapamil, edrophonium, phenylephrine and isoproterenol. Conduction over the Mahaim fiber was blocked by adenosine, but not verapamil. The time course of adenosine induced block over the Mahaim fiber differed from adenosine induced AV nodal block. Mahaim fibers are decrementally conducting pathways that are adenosine sensitive. These findings support the concept that conduction in accessory pathways manifesting decremental properties is not mediated by the calcium channel.
结室旁路（Mahaim纤维）的存在已被用来解释某些独特的心电图和电生理观察结果。许多这类患者已证实存在具有递减传导特性的房室或房束纤维。我们报告了1例有Mahaim纤维的患者以及给予腺苷、普鲁卡因胺、恩卡胺、维拉帕米、依酚氯铵、去氧肾上腺素和异丙肾上腺素后该旁路的传导反应。腺苷可阻断Mahaim纤维的传导，但维拉帕米不能。腺苷诱导的Mahaim纤维传导阻滞的时间过程与腺苷诱导的房室结传导阻滞不同。Mahaim纤维是对腺苷敏感的递减传导通路。这些发现支持以下概念，即表现出递减特性的旁路传导不是由钙通道介导的。
