Podrid P J, Schoeneberger A, Lown B, Lampert S, Matos J, Porterfield J, Raeder E, Corrigan E
Am Heart J. 1983 Feb;105(2):181-8. doi: 10.1016/0002-8703(83)90512-4.
From a population of 260 patients with malignant ventricular arrhythmia (ventricular fibrillation or ventricular tachycardia with syncope) we identified 52 (20%) who had infrequent ventricular premature beats during exercise testing and 48 hours of ambulatory monitoring. These patients underwent invasive electrophysiologic study utilizing programmed premature stimulation with up to three extrastimuli at currents of twice and three times middiastolic threshold. The end point for testing was nonsustained ventricular tachycardia (NSVT), defined as 3 to 20 propagated responses resulting from the last premature stimulus. A multiple response was obtained in 45 patients consisting of reproducible NSVT in 36 and sustained ventricular tachycardia in nine. The 36 patients with NSVT underwent 540 electrophysiologic tests with 18 antiarrhythmic agents. Suppression of the repetitive response was achieved in 31 of the 36 patients (86.1%). After an average follow-up of 21 months, one of 31 patients in whom the repetitive response had been abolished had recurrent arrhythmia. This contrasted with recurrence in two of the five patients in whom NSVT was still provoked. During the extensive testing, ventricular fibrillation was not induced. Sustained ventricular tachycardia occurred in 27 of the 540 tests (5.0%), but cardioversion was required in only 12 (2.2%). We conclude that NSVT constitutes a safe electrophysiologic end point for selecting an effective antiarrhythmic program in patients who have experienced malignant ventricular arrhythmia but in whom monitoring and exercise testing are inadequate to guide therapy.
在260例恶性室性心律失常（室颤或伴有晕厥的室性心动过速）患者中，我们识别出52例（20%）在运动试验及48小时动态监测期间有偶发室性早搏的患者。这些患者接受了有创电生理研究，采用程控早搏刺激，在舒张中期阈值的两倍和三倍电流下给予多达3个额外刺激。测试的终点是非持续性室性心动过速（NSVT），定义为由最后一个早搏刺激引发的3至20个传导反应。45例患者获得了多次反应，其中36例为可重复性NSVT，9例为持续性室性心动过速。36例NSVT患者接受了18种抗心律失常药物的540次电生理测试。36例患者中有31例（86.1%）的重复反应得到抑制。平均随访21个月后，31例重复反应已消除的患者中有1例出现心律失常复发。这与5例仍可诱发NSVT的患者中有2例复发形成对比。在广泛测试期间，未诱发室颤。540次测试中有27次（5.0%）发生持续性室性心动过速，但仅12次（2.2%）需要进行心脏复律。我们得出结论，对于经历过恶性室性心律失常但监测和运动试验不足以指导治疗的患者，NSVT是选择有效抗心律失常方案的安全电生理终点。
