Department of Physics, University of California, San Diego (W.-J.R.).
Department of Medicine, Stanford University, Palo Alto (T.B., P.G., A.J.R., S.M.N.).
Circ Arrhythm Electrophysiol. 2024 Mar;17(3):e012041. doi: 10.1161/CIRCEP.123.012041. Epub 2024 Feb 13.
Atrial fibrillation is the most common cardiac arrhythmia in the world and increases the risk for stroke and morbidity. During atrial fibrillation, the electric activation fronts are no longer coherently propagating through the tissue and, instead, show rotational activity, consistent with spiral wave activation, focal activity, collision, or partial versions of these spatial patterns. An unexplained phenomenon is that although simulations of cardiac models abundantly demonstrate spiral waves, clinical recordings often show only intermittent spiral wave activity.
In silico data were generated using simulations in which spiral waves were continuously created and annihilated and in simulations in which a spiral wave was intermittently trapped at a heterogeneity. Clinically, spatio-temporal activation maps were constructed using 60 s recordings from a 64 electrode catheter within the atrium of N=34 patients (n=24 persistent atrial fibrillation). The location of clockwise and counterclockwise rotating spiral waves was quantified and all intervals during which these spiral waves were present were determined. For each interval, the angle of rotation as a function of time was computed and used to determine whether the spiral wave returned in step or changed phase at the start of each interval.
In both simulations, spiral waves did not come back in phase and were out of step." In contrast, spiral waves returned in step in the majority (68%; =0.05) of patients. Thus, the intermittently observed rotational activity in these patients is due to a temporally and spatially conserved spiral wave and not due to ones that are newly created at the onset of each interval.
Intermittency of spiral wave activity represents conserved spiral wave activity of long, but interrupted duration or transient spiral activity, in the majority of patients. This finding could have important ramifications for identifying clinically important forms of atrial fibrillation and in guiding treatment.
心房颤动是世界上最常见的心律失常，会增加中风和发病的风险。在心房颤动中，电激活前沿不再连贯地穿过组织传播，而是呈现出旋转活动，与螺旋波激活、局灶活动、碰撞或这些空间模式的部分版本一致。一个未解释的现象是，尽管心脏模型的模拟充分展示了螺旋波，但临床记录通常只显示间歇性螺旋波活动。
使用连续产生和消除螺旋波的模拟以及间歇性捕获螺旋波的模拟在计算机上生成数据。在临床上，使用来自 34 名患者（24 名持续性心房颤动）心房内 64 电极导管的 60 秒记录构建时空激活图。顺时针和逆时针旋转螺旋波的位置被量化，确定所有存在这些螺旋波的间隔。对于每个间隔，计算旋转角度随时间的变化，并确定螺旋波是否在每个间隔开始时同步返回或改变相位。
在两种模拟中，螺旋波都没有同步返回，而是不同步。相比之下，在大多数（68%；=0.05）患者中，螺旋波同步返回。因此，这些患者间歇性观察到的旋转活动是由于一个时间和空间上都保持不变的螺旋波，而不是由于在每个间隔开始时新创建的螺旋波。
螺旋波活动的间歇性代表了大多数患者中长但中断的持续时间或短暂的螺旋活动的保守螺旋波活动。这一发现可能对识别临床上重要的心房颤动形式和指导治疗具有重要意义。
