Kottkamp H, Hindricks G, Chen X, Willems S, Breithardt G, Borggrefe M
Medizinische Klinik und Poliklinik, Innere Medizin C (Kardiologie/Angiologie), Westfälische Wilhelms-Universität Münster.
Z Kardiol. 1994 Aug;83(8):577-81.
Radiofrequency catheter ablation has become an established treatment modality for definite cure of patients with WPW-syndrome or concealed accessory pathways. On-line monitoring of the induced tissue effects plays an important role concerning the efficacy and safety of this procedure. In a 50 year-old man with recurrent atrioventricular tachycardia, endocardial catheter mapping revealed a left anterolateral concealed accessory pathway. A temperature-guided radiofrequency pulse with a preselected temperature of 70 degrees C was applied during tachycardia when stability of the local electrogram, continuous ventriculoatrial activity during orthodromic tachycardia, and registration of a Kent-potential indicated electrogram criteria for a successful ablation. However, orthodromic tachycardia did not terminate, and catheter tip temperature only reached a plateau of 45 degrees C with maximal power output of 50 watts indicating an insufficient catheter tip-tissue-contact. Therefore, the bending of the catheter curve was slightly straightened during energy application without pushing the catheter forward in order to achieve a better tip electrode contact with the tissue. Simultaneously, a sudden increase in catheter tip temperature was observed accompanied by termination of the tachycardia indicative of the successful ablation of the accessory pathway. At present, a control of radiofrequency catheter induced tissue effects can be best achieved by temperature-guided energy application whereas monitoring of current, voltage, and impedance are insufficient in this respect. In the present case, correction of the catheter placement during energy application could be achieved because of the on-line monitoring of the catheter tip temperature thereby allowing successful ablation of the accessory pathway with a single radiofrequency pulse.
射频导管消融已成为明确治愈预激综合征或隐匿性旁路患者的既定治疗方式。对诱导的组织效应进行在线监测对该手术的疗效和安全性起着重要作用。在一名患有复发性房室性心动过速的50岁男性中，心内膜导管标测显示左前外侧隐匿性旁路。在心动过速期间，当局部电图稳定、顺向性心动过速期间持续的室房活动以及记录到肯特电位表明符合成功消融的电图标准时，应用预选温度为70摄氏度的温度引导射频脉冲。然而，顺向性心动过速并未终止，导管尖端温度仅达到45摄氏度的平台期，最大功率输出为50瓦，表明导管尖端与组织的接触不足。因此，在施加能量期间，将导管曲线的弯曲稍微拉直，而不向前推动导管，以实现尖端电极与组织的更好接触。同时，观察到导管尖端温度突然升高，同时心动过速终止，这表明旁路成功消融。目前，通过温度引导能量施加可以最好地控制射频导管诱导的组织效应，而在这方面监测电流、电压和阻抗是不够的。在本病例中，由于对导管尖端温度进行在线监测，在施加能量期间可以实现导管位置的校正，从而允许用单个射频脉冲成功消融旁路。
