Gencel L, Poquet F, Gosse P, Haissaguerre M, Marcus F I, Clementy J
Hopital Cardiologique, University of Bordeaux, France.
Pacing Clin Electrophysiol. 1994 Nov;17(11 Pt 2):2118-24. doi: 10.1111/j.1540-8159.1994.tb03811.x.
Atrial fibrillation is considered the main cause of cardioembolic strokes. After detailed investigations, about 30% of ischemic strokes remain unexplained. A percentage of these ischemic attacks may result from asymptomatic episodes of paroxysmal atrial fibrillation (PAF). Previous studies have demonstrated that electrophysiological testing and signal-averaged P wave (SAPW) ECG are useful to detect patients with PAF.
Twenty patients with unexplained ischemic strokes had electrophysiological studies (EPS) to determine atrial vulnerability and SAPW recordings. At EPS, patients were classified in group I (10 patients) if they had a latent atrial vulnerability index < 2 and/or more than 1 minute of sustained atrial arrhythmia. Otherwise they were classified in group II (10 patients). In group I, the filtered P wave duration was greater: 142 versus 120 msec (P = 0.03) and RMS 30 tended to be lower: 2.54 versus 4.13 microV (P = 0.11) than in group II. A filtered P wave duration > 125 msec associated with a RMS 30 < 3 microV had a positive predictive value of 78% and a negative predictive value of 88% for the detection of patients with abnormal atrial vulnerability at EPS.
SAPW may be useful to identify patients at risk of PAF who may be candidates for EPS.
心房颤动被认为是心源性栓塞性中风的主要原因。经过详细调查，约30%的缺血性中风仍无法解释。这些缺血性发作中有一部分可能源于阵发性心房颤动（PAF）的无症状发作。先前的研究表明，电生理测试和信号平均P波（SAPW）心电图有助于检测PAF患者。
20例不明原因缺血性中风患者进行了电生理研究（EPS）以确定心房易损性并记录SAPW。在EPS中，如果患者的潜在心房易损性指数<2和/或持续房性心律失常超过1分钟，则将其分为I组（10例患者）。否则他们被分为II组（10例患者）。在I组中，滤波后的P波持续时间更长：142对120毫秒（P = 0.03），RMS 30往往更低：2.54对4.13微伏（P = 0.11），比II组低。滤波后的P波持续时间>125毫秒且RMS 30<3微伏对检测EPS时心房易损性异常的患者具有78%的阳性预测值和88%的阴性预测值。
SAPW可能有助于识别有PAF风险的患者，这些患者可能是EPS的候选者。
