Fujimura O, Yee R, Klein G J, Sharma A D, Boahene K A
Department of Medicine, University Hospital, London, Canada.
N Engl J Med. 1989 Dec 21;321(25):1703-7. doi: 10.1056/NEJM198912213212503.
Although electrophysiologic testing accurately delineates abnormalities in patients with fixed cardiac-conduction defects, its sensitivity in identifying transient rhythm disturbances is unknown. We prospectively studied 21 patients who had electrocardiographically documented intermittent atrioventricular block (n = 13) or sinus pauses (n = 8) causing syncope, but whose cardiac rhythm had reverted to normal by the time of referral. There were 14 men and 7 women, with a mean age (+/- SD) of 63 +/- 13 years. Fourteen patients had organic heart disease, and 8 were taking cardioactive medications. Electrophysiologic testing was performed before the implantation of a permanent pacemaker. Only three of the eight patients with documented sinus pauses had abnormalities during their tests that suggested the correct diagnosis (sensitivity, 37.5 percent), including a prolonged sinus-node recovery time in one and carotid-sinus hypersensitivity in two. Three of the eight patients had abnormalities detected that were unrelated to syncope, including atrial flutter, dual atrioventricular nodal pathways, and sustained monomorphic ventricular tachycardia. Of the 13 patients with documented atrioventricular block, only 2 had abnormalities suggesting the correct diagnosis (sensitivity, 15.4 percent). Additional observations unrelated to syncope among these 13 patients included abnormal sinus-node function, atrial flutter, and atrial fibrillation causing hypotension. These preliminary observations suggest that a negative electrophysiologic test in a patient with a normal cardiac rhythm who has experienced syncope does not exclude a transient bradyarrhythmia as a cause of the syncope. Furthermore, electrophysiologic testing may sometimes reveal unrelated rhythm disturbances that may mistakenly be designated as the cause of the syncope.
虽然电生理检查能准确地描绘出患有固定性心脏传导缺陷患者的异常情况，但其在识别短暂性心律失常方面的敏感性尚不清楚。我们前瞻性地研究了21例经心电图记录有间歇性房室传导阻滞（n = 13）或窦性停搏（n = 8）导致晕厥的患者，但在转诊时其心律已恢复正常。其中男性14例，女性7例，平均年龄（±标准差）为63±13岁。14例患者患有器质性心脏病，8例正在服用心脏活性药物。在植入永久性起搏器之前进行了电生理检查。在记录有窦性停搏的8例患者中，只有3例在检查期间出现异常提示正确诊断（敏感性为37.5%），其中1例窦性结恢复时间延长，2例颈动脉窦过敏。8例患者中有3例检测到与晕厥无关的异常，包括心房扑动、双房室结径路和持续性单形性室性心动过速。在记录有房室传导阻滞的13例患者中，只有2例出现异常提示正确诊断（敏感性为15.4%）。这13例患者中与晕厥无关的其他观察结果包括异常的窦性结功能、心房扑动和导致低血压的心房颤动。这些初步观察结果表明，对于经历过晕厥但心律正常的患者，电生理检查结果为阴性并不能排除短暂性缓慢性心律失常是晕厥的原因。此外，电生理检查有时可能会发现与晕厥无关的心律失常，这些心律失常可能会被错误地认定为晕厥的原因。
