Huycke E C, Lai W T, Nguyen N X, Keung E C, Sung R J
Department of Medicine, Letterman Army Medical Center, San Francisco, California.
Am J Cardiol. 1989 Nov 15;64(18):1131-7. doi: 10.1016/0002-9149(89)90865-5.
To assess the role of intravenous isoproterenol for the facilitation of electrophysiologic induction of atrioventricular (AV) node reentrant tachycardia, 20 patients with dual AV node pathways who lacked inducible AV node reentrant tachycardia at control study had a constant isoproterenol infusion administered and underwent repeat study. Six (30%) of 20 patients (group I) had inducible AV node reentrant tachycardia during isoproterenol infusion whereas the other 14 (70%) patients (group II) did not. Paroxysmal supraventricular tachycardia was clinically documented in all 6 group I patients compared to 3 (21%) of 14 group II patients (p = 0.002). The sensitivity and specificity of isoproterenol-facilitated induction of AV node reentrant tachycardia were 67 and 100%, respectively. The isoproterenol-facilitated induction of sustained AV node reentry was mediated by resolution of the weak link in anterograde slow pathway in 2 (33%) patients, in retrograde fast pathway in 3 (50%) and in both anterograde slow and retrograde fast pathways in 1 (17%) patient. Four group I patients were given intravenous propranolol, 0.2 mg/kg body weight, and had complete suppression of isoproterenol-facilitated induction of AV node reentry. Thus, intravenous isoproterenol is a rather sensitive and highly specific adjunct to electrophysiologic induction of AV node reentrant tachycardia in patients with dual AV node pathways but without inducible sustained AV node reentry.
为评估静脉注射异丙肾上腺素在促进房室（AV）结折返性心动过速电生理诱发中的作用，对20例在对照研究中未诱发出AV结折返性心动过速的双AV结径路患者持续静脉输注异丙肾上腺素，并进行重复研究。20例患者中的6例（30%，I组）在输注异丙肾上腺素期间诱发出AV结折返性心动过速，而其他14例患者（70%，II组）未诱发。I组的所有6例患者均有阵发性室上性心动过速的临床记录，而II组14例患者中有3例（21%）有记录（p = 0.002）。异丙肾上腺素促进AV结折返性心动过速诱发的敏感性和特异性分别为67%和100%。异丙肾上腺素促进的持续性AV结折返的诱发，在2例（33%）患者中是通过消除顺向慢径路中的薄弱环节介导的，在3例（50%）患者中是通过逆向快径路介导的，在1例（17%）患者中是通过顺向慢径路和逆向快径路两者介导的。4例I组患者静脉注射了0.2 mg/kg体重的普萘洛尔，异丙肾上腺素促进的AV结折返诱发被完全抑制。因此，对于双AV结径路但未诱发出持续性AV结折返的患者，静脉注射异丙肾上腺素是电生理诱发AV结折返性心动过速的一种相当敏感且高度特异的辅助手段。
