Cosio F G, López-Gil M, Goicolea A, Arribas F
Hospital Universitario de Getafe, Madrid, Spain.
Clin Cardiol. 1992 Sep;15(9):667-73. doi: 10.1002/clc.4960150910.
The clinical electrophysiologic approaches to atrial flutter (F) have been activation mapping and the observation of changes induced by programmed stimulation. Sequential endocardial activation mapping has recently yielded information indicating that common F is produced by a large right atrial (RA) reentry circuit, with counterclockwise rotation in the frontal plane, including the inferior vena cava in its center. Functional block in the crista terminalis and conduction slowing in the approaches to the atrioventricular node seem to be important to support reentry. F inscribing positive deflections in the inferior leads usually follows the same path, but in a clockwise direction. Atypical F may be produced by left atrial circuits. Atrial stimulation during F entrains the circuit, resetting it with each stimulus. Collision between antidromic and orthodromic activation during entrainment produces fusion that can be identified in the surface electrocardiogram. The last paced activation restarts F, unless circuit penetration has been enough to modify it by block or disorganization. Entrainment may result in F acceleration, with changes in activation sequence, suggesting a different type of reentry, possibly based on functional factors.
心房扑动（F）的临床电生理方法包括激动标测以及观察程序刺激所诱发的变化。序贯心内膜激动标测最近获得的信息表明，常见的F是由一个大的右心房（RA）折返环产生的，在额面呈逆时针旋转，其中心包括下腔静脉。界嵴的功能性阻滞以及房室结附近的传导减慢似乎对维持折返很重要。在下壁导联记录到正向波的F通常沿相同路径，但方向为顺时针。非典型F可能由左心房环路产生。F发作时进行心房刺激可拖带该环路，每次刺激都会使其重置。拖带期间逆向激动与正向激动之间的碰撞产生融合，可在体表心电图中识别。除非环路被穿透足以通过阻滞或紊乱对其进行改变，否则最后一次起搏激动会重新启动F。拖带可能导致F加速，激动顺序发生变化，提示可能存在基于功能因素的不同类型的折返。
