Michelson E L, Morganroth J
Circulation. 1980 Apr;61(4):690-5. doi: 10.1161/01.cir.61.4.690.
Variations in the frequency of complex ventricular arrhythmias were evaluated by consecutive 24-hour long-term electrocardiographic recordings over 4 days using a two-channel recorder and computer-assisted analysis system with a weighted relative mean error of 7.5 +/ 5% (SD). Twenty patients (mean age 58 +/- 9 years [SD] with various cardiac disorders were selected if they had a daily average of more than 30 ventricular ectopic complexes per hour. Twenty patients had ventricular couplets and 14 patients had ventricular tachycardia (at least triplets). The mean daily number of either couplets or ventricular tachycardia was subjected a four-factor nested analysis of variance to determine the sources of variation in ectopic frequency. Differences in hourly rates accounted for 30% of the variation in the frequency of ectopic complexes. Statistical methods were applied to determine the change in frequency of complex arrhythmias necessary to exceed that attributable to spontaneous variation alone at the p less than 0.05 level. Using a typical protocol, for example, comparing a 24-hour test period with a 24-hour control period would require a 65% decrease in mean hourly frequency of ventricular tachycardia and 75% reduction in the frequency of couplets to demonstrate therapeutic efficacy rather than a reduction due to spontaneous variation alone.
采用双通道记录仪和计算机辅助分析系统，在4天内连续进行24小时长期心电图记录，以评估复杂室性心律失常频率的变化，该系统加权相对平均误差为7.5±5%（标准差）。如果每小时室性异位复合波的日平均数量超过30个，则选择20名患有各种心脏疾病的患者（平均年龄58±9岁[标准差]）。20名患者有室性成对早搏，14名患者有室性心动过速（至少三联律）。对成对早搏或室性心动过速的每日平均数量进行四因素嵌套方差分析，以确定异位频率变化的来源。每小时发生率的差异占异位复合波频率变化的30%。应用统计方法确定在p<0.05水平时，复杂心律失常频率的变化，该变化必须超过仅由自发变化引起的频率变化。例如，使用典型方案，将24小时测试期与24小时对照期进行比较，室性心动过速的平均每小时频率需要降低65%，成对早搏的频率需要降低75%，才能证明治疗效果，而不仅仅是由于自发变化导致的降低。
