Klingenheben Thomas, Ptaszynski Pawel, Hohnloser Stefan H
Division of Clinical Electrophysiology, Department of Cardiology, J.W. Goethe University, D-60590 Frankfurt, Germany.
J Cardiovasc Electrophysiol. 2005 Jun;16(6):620-4. doi: 10.1111/j.1540-8167.2005.40708.x.
T-wave alternans has been shown to be linked to the genesis of ventricular tachyarrhythmias. Currently, only qualitative assessment of microvolt T-wave alternans (MTWA) is recommended in clinical practise. Whether quantitative assessment of MTWA yields complementary information is unknown.
Noninvasive MTWA determination was performed in 204 consecutive patients with ischemic or nonischemic cardiomyopathy. Of those, 100 tested MTWA positive. In these recordings, MTWA magnitude was quantitatively assessed (alternans voltage, V(alt)). Patients were followed for a mean of 17 months. Ventricular tachyarrhythmic events constituted the study endpoint. Patients with nonischemic cardiomyopathy had a higher V(alt) than patients with ischemic cardiomyopathy (10.3 +/- 9.2 [median 7.2] vs 6.2 +/- 3.2 [median 4.6] microV; P = 0.007). The number of MTWA-positive ECG leads was also higher in patients nonischemic cardiomyopathy (7.3 +/- 2.4 [median 8] vs 6.0 +/- 2.5 [median 6]; P = 0.016). Patients who suffered an arrhythmic event during follow-up had higher MTWA voltages (10.8 +/- 10.0 [median 8.8] vs 7.4 +/- 5.7 [median 6.4] microV; P = 0.05) a higher number of MTWA-positive ECG leads (7.6 +/- 2.4 [median 8] vs 6.4 +/- 2.5 [median 6]; P = 0.05) compared to patients with an uncomplicated course.
Patients with nonischemic cardiomyopathy and patients with tachyarrhythmic complications have more extensive MTWA possibly reflecting more extensive myocardial damage and a higher arrhythmia propensity.
T波交替已被证明与室性快速心律失常的发生有关。目前，临床实践中仅推荐对微伏级T波交替（MTWA）进行定性评估。MTWA的定量评估是否能提供补充信息尚不清楚。
对204例连续的缺血性或非缺血性心肌病患者进行了无创MTWA测定。其中，100例MTWA检测呈阳性。在这些记录中，对MTWA幅度进行了定量评估（交替电压，V(alt)）。患者平均随访17个月。室性快速心律失常事件构成研究终点。非缺血性心肌病患者的V(alt)高于缺血性心肌病患者（10.3±9.2[中位数7.2]对6.2±3.2[中位数4.6]微伏；P = 0.007）。非缺血性心肌病患者中MTWA阳性心电图导联的数量也更高（7.3±2.4[中位数8]对6.0±2.5[中位数6]；P = 0.016）。与随访过程无并发症的患者相比，随访期间发生心律失常事件的患者具有更高的MTWA电压（10.8±10.0[中位数8.8]对7.4±5.7[中位数6.4]微伏；P = 0.05）和更高数量的MTWA阳性心电图导联（
