Klingenheben T, Credner S, Li Y G, Bender B, Hohnloser S H
Medizinische Klinik IV, Frankfurt a. Main.
Z Kardiol. 2000;89 Suppl 3:57-61.
Prospective identification of patients with structural heart disease who could profit from prophylactic ICD therapy is hampered by the low predictive power of the currently available risk stratification parameters. Microvolt T wave alternans measured noninvasively is a new promising parameter to assess impaired ventricular repolarization which has been associated with an increased incidence of ventricular tachyarrhythmias. T wave alternans is rate-dependent; to induce alternans, heart rate may be increased by atrial stimulation during invasive EP testing or noninvasively by exercise stress testing. The first clinical validation with respect to prediction of inducibility of ventricular tachyarrhythmias and of arrhythmic events during follow-up in patients undergoing invasive EP testing was reported in 1994. Subsequently, a good concordance between the results of invasive and noninvasive assessment of T wave alternans was demonstrated by our group. The first prospective evaluation of the noninvasive alternans measurement using submaximal exercise testing was performed in patients surviving prehospital ventricular fibrillation or sustained ventricular tachycardia referred to our institution. The occurrence of T wave alternans in this patient population was predictive of future tachyarrhythmic events with subsequent appropriate ICD therapy. The results of the currently performed prospective trials in various patient populations will help to establish the utility of T wave alternans assessment as a risk stratifier in clinical practice.
目前可用的风险分层参数预测能力较低，这阻碍了对可能从预防性植入式心律转复除颤器（ICD）治疗中获益的结构性心脏病患者进行前瞻性识别。无创测量的微伏级T波电交替是评估心室复极受损的一个新的有前景的参数，它与室性快速性心律失常的发生率增加有关。T波电交替与心率有关；在有创电生理检查期间，可通过心房刺激增加心率以诱发电交替，或通过运动负荷试验进行无创诱发。1994年报道了关于预测接受有创电生理检查患者室性快速性心律失常的诱发性以及随访期间心律失常事件的首次临床验证。随后，我们小组证明了T波电交替有创和无创评估结果之间具有良好的一致性。对转诊至我们机构的院外心室颤动或持续性室性心动过速存活患者，首次使用次极量运动试验对无创电交替测量进行了前瞻性评估。该患者群体中T波电交替的出现可预测未来的快速性心律失常事件以及随后进行的适当ICD治疗。目前在各种患者群体中进行的前瞻性试验结果将有助于确立T波电交替评估作为临床实践中风险分层工具的实用性。
