相邻小时之间室性早搏密度的自发变异

SPONTANEOUS VARIABILITY OF VENTRICULAR PREMATURE CONTRACTIONS DENSITY BETWEEN ADJACENT HOURS

目的：研究相邻小时与小时之间室性早搏（ＶＰＣ）密度的自发变异。方法：分析２００例ＶＰＣ（≥２４０次／２４ｈ）病人２４ｈ动态心电图，其中男９１例，女１０９例，平均年龄（４０９±１４４）岁。临床诊断冠心病６４例，高血压病１６例，其他心脏病６例；１１４例未发现器质性心脏病。记录动态心电图前停用所有抗心律失常药至少５个半衰期。应用直线回归分析，观察ＶＰＣ密度相邻小时与小时之间的相关性。每小时ＶＰＣ密度既视为其前１ｈＶＰＣ密度的因变量，又作为其后１ｈＶＰＣ密度的自变量。结果：２００例中，ＶＰＣ密度相邻小时与小时之间存在直线相关关系者共１５４例（７７０％），平均相关系数０６５７７±０１３３０。逐步回归分析显示，相邻小时与小时之间ＶＰＣ密度的相关性与ＶＰＣ小时数百分比、平均每小时ＶＰＣ密度、ＶＰＣ提前指数以及是否存在二或三联律有关，与年龄、性别、基础心脏病、平均心率无关。２４ｈＶＰＣ密度分布呈昼夜节律。结论：相邻小时与小时之间ＶＰＣ密度的自发变异存在直线相关。

Objective: To determine the characteristcs of spontaneous variability of ventricular premature contractons (VPCs) density between adjacent hours. Methods: 24 hour Holter electrocardiogram was analysed in 200 consecutive patients with VPCs which density was at least 240 per hour (91 male, 109 female, mean age (40 9±14 4) yr old after withdrawing antiarrhythmic agents for at least 5 half lives. The underlying heart diseases included coronary heart disease in 64, essential hypertension in 16, and other heart diseases in 6 patient. In the remaining 114 patients organic heart diseases were not detected. Linear regression analysis, in which VPCs density hourly serves as the dependent variable (y 1) for its predecessor (x 1) and the independent variable (x 2 ) for its successor (y 2) as well, was used to describe the relationship of VPCs density variations. Results:In 200 patients, presence of linear correlation of VPCs density between successive hours was found in 154 patients (77 0%) with mean correlation coefficients 0 6577±0 1330. Stepwise regression analysis revealed that the closeness of linear correlation of VPCs density between successive hours was mainly affected by the percent VPCs hours, mean VPCs density per hours, VPCs premature index, and presence or absence of VPCs bigeminy or trigeminy. Whereas age, sex, underlying heart disease, and mean heart tate exerted no independent influence on VPCs density of hour to hour variability. There was a circadian distribution of VPCs density with a peak at day time and a nadir at night time. Conclusion: Linear correlations of VPCs density between adjacent hours in patients with chronic arrhythmias were well demonstrated.