Steinbigler P, Haberl R, Steinbeck G
Medical Hospital I, University of Munich, Germany.
J Cardiovasc Electrophysiol. 1999 Oct;10(10):1316-22. doi: 10.1111/j.1540-8167.1999.tb00185.x.
The influence of myocardial ischemia on the detection of an arrhythmogenic substrate with the signal-averaged ECG is unclear.
In 80 patients with single vessel coronary artery disease and a critical stenosis of the left anterior descending vessel selected after coronary angiography in whom percutaneous transluminal coronary angioplasty (PTCA) was planned, we retrospectively investigated the signal-averaged ECGs in the time domain before, during, and after occlusion of the coronary artery by the PTCA balloon. Forty patients were resuscitated from ventricular fibrillation (VF group), and 40 patients had no ventricular arrhythmia (non-VF group). Late potentials were seen at rest in 26 of 40 patients in the VF group. During ischemia, the duration of the filtered QRS complex and the duration of low-amplitude signals < 40 microV increased significantly. In another 14 patients in the VF group, late potentials were observed only during ischemia. In 4 of 26 patients in the VF group without prior infarction but with severe ischemia present at rest, successful PTCA eliminated preexistent late potentials. In the non-VF group, one patient had late potentials present at rest. In two patients with prior infarction, late potentials were provokable only during transmural ischemia.
Myocardial ischemia is able to modify detection of an arrhythmogenic substrate with the signal-averaged ECG.
心肌缺血对通过信号平均心电图检测致心律失常基质的影响尚不清楚。
在80例经冠状动脉造影选择的单支冠状动脉疾病且左前降支血管严重狭窄、计划进行经皮腔内冠状动脉成形术（PTCA）的患者中，我们回顾性研究了PTCA球囊阻塞冠状动脉前、中、后的时域信号平均心电图。40例患者从室颤中复苏（室颤组），40例患者无室性心律失常（非室颤组）。室颤组40例患者中有26例静息时出现晚电位。缺血期间，滤波后的QRS波群持续时间和低振幅信号（<40微伏）持续时间显著增加。室颤组另外14例患者仅在缺血期间观察到晚电位。室颤组26例无既往梗死但静息时有严重缺血的患者中，4例PTCA成功消除了先前存在的晚电位。在非室颤组中，1例患者静息时出现晚电位。在2例有既往梗死的患者中，仅在透壁缺血期间可诱发晚电位。
心肌缺血能够改变通过信号平均心电图对致心律失常基质的检测。
