Hess D S, Morady F, Scheinman M M
Am J Cardiol. 1982 Dec;50(6):1309-15. doi: 10.1016/0002-9149(82)90468-4.
Thirty-two patients were prospectively evaluated for syncope (recurrent in 26 patients) with conventional neurologic and cardiovascular testing without elucidation of a cause. All patients underwent invasive electrophysiologic studies to assess sinus nodal function, atrioventricular conduction, and the inducibility of supraventricular and ventricular tachycardia (VT). Eleven patients (34%) were found to have laboratory-induced VT, 5 patients (15%) had evidence of sinus nodal dysfunction, 1 patient (3%) had infra-His atrioventricular block during atrial pacing, and 1 patient (3%) had probable quinidine-related VT. The remaining 14 patients had no detectable abnormalities during electrophysiologic study. After a mean follow-up period of 21.3 +/- 1.2 months, 10 of the 11 patients with inducible VT were asymptomatic while receiving laboratory-directed antiarrhythmic therapy, and 1 patient died from ventricular fibrillation after discontinuing the chosen antiarrhythmic regimen. Five of the remaining 7 patients with an electrophysiologic abnormality were asymptomatic after implantation of a permanent pacemaker or alteration of previous drug therapy, or both. The 14 patients with a normal electrophysiologic study were treated empirically, with recurrent syncope occurring in 4 of these patients during the follow-up period. Invasive electrophysiologic studies provided a presumptive diagnosis in 56% of patients with syncope of undetermined origin. Previously unsuspected VT accounted for 61% (11 of 18) of the detected abnormalities. Therapy specific for the electrophysiologic abnormality was usually successful in preventing recurrent syncope.
对32例晕厥患者（26例为复发性晕厥）进行了前瞻性评估，采用传统的神经学和心血管检查方法，但未明确病因。所有患者均接受了有创电生理检查，以评估窦房结功能、房室传导以及室上性和室性心动过速（VT）的诱发性。发现11例患者（34%）有实验室诱发的VT，5例患者（15%）有窦房结功能障碍的证据，1例患者（3%）在心房起搏时出现希氏束下房室传导阻滞，1例患者（3%）可能有与奎尼丁相关的VT。其余14例患者在电生理检查中未发现可检测到的异常。在平均随访21.3±1.2个月后，11例可诱发VT的患者中有10例在接受实验室指导的抗心律失常治疗时无症状，1例患者在停用所选抗心律失常方案后死于心室颤动。其余7例有电生理异常的患者中有5例在植入永久性起搏器或改变先前的药物治疗或两者兼施后无症状。14例电生理检查正常的患者接受了经验性治疗，其中4例患者在随访期间出现复发性晕厥。有创电生理检查为56%病因不明的晕厥患者提供了初步诊断。先前未被怀疑的VT占检测到异常的61%（18例中的11例）。针对电生理异常的治疗通常成功地预防了复发性晕厥。
