Benditt D G, Strauss H C, Scheinman M M, Behar V S, Wallace A G
Circulation. 1976 Sep;54(3):436-41. doi: 10.1161/01.cir.54.3.436.
The first ten cycles following cessation of atrial pacing were evaluated in 44 control subjects (mean age 52.9 +/- 14.88 yr) and 39 patients (mean age 62.9 +/- 15.41 yr) suspected of having sinus node dysfunction (SND). The maximal cycle length for each postpacing cycle following several pacing periods in each control subject was determined, and was normalized by dividing it by the subject's mean spontaneous control cycle length (SCL). Using the control group, a normalized maximal post-pacing response pattern (mean and SD) was derived. For each SND patient, a composite SD for each post-pacing cycle was calculated by adding the patient's SCL variance to the variance determined for each post-pacing cycle in the control group. Two composite SD above the mean value for each post-pacing cycle was selected as the upper limit of the normal recovery response and used to identify abnormal post-pacing responses in the 39 SND patients. Abnormally prolonged cycle lengths subsequent to the first escape cycle (secondary pauses) were found in 16/39 (41.0%) patients, of whom 11/39 (28.2%) had a prolonged SNRTmax. Of importance, 11/12 (91;7%) patients with documented SA block or sinus pauses prior to electrophysiologic study, demonstrated secondary pauses, while only 7/12 (58.3%) had a prolonged SNRTmax. Criteria are derived for the identification of secondary pauses during the postpacing period, and a close association between secondary pauses and the presence of spontaneous SA block or sinus pauses prior to electrophysiologic study is demonstrated.
对44名对照受试者（平均年龄52.9±14.88岁）和39名疑似患有窦房结功能障碍（SND）的患者（平均年龄62.9±15.41岁），评估了心房起搏停止后的前十个心动周期。确定了每个对照受试者在几个起搏周期后的每个起搏后心动周期的最大周期长度，并通过将其除以受试者的平均自发对照周期长度（SCL）进行标准化。利用对照组，得出了标准化的最大起搏后反应模式（平均值和标准差）。对于每名SND患者，通过将患者的SCL方差与对照组中每个起搏后心动周期确定的方差相加，计算每个起搏后心动周期的复合标准差。将每个起搏后心动周期高于平均值的两个复合标准差作为正常恢复反应的上限，并用于识别39名SND患者中异常的起搏后反应。在16/39（41.0%）的患者中发现首次逸搏周期（继发性停顿）后出现异常延长的周期长度，其中11/39（28.2%）的患者SNRTmax延长。重要的是，在电生理研究前记录有窦房阻滞或窦性停搏的11/12（91.7%）患者出现继发性停顿，而只有7/12（58.3%）的患者SNRTmax延长。得出了在起搏后期间识别继发性停顿的标准，并证明了继发性停顿与电生理研究前自发窦房阻滞或窦性停搏的存在之间密切相关。
