Stein P K, Rottman J N, Kuru T, Kleiger R E
Division of Cardiology, Jewish Hospital of St. Louis, MO 63110, USA.
Int J Cardiol. 1995 Jan 27;48(1):59-65. doi: 10.1016/0167-5273(94)02220-d.
We investigated the effects of moricizine HCl, a type Ic anti-arrhythmic agent, on heart rate variability. Decreased heart rate variability is a risk factor for mortality in post-MI and other patient populations, and some antiarrhythmic drugs decrease heart rate variability. Normal volunteers (10 M, 11 F, age 19-39 years) received blinded placebo and moricizine HCl at 200 mg twice daily for 5 days. On day 4, a 24-h ECG was obtained, and time and frequency domain measures of heart rate variability based on normal-to-normal intervals were computed. Moricizine decreased both time and frequency domain measures of heart rate variability. Significant reductions were seen for SDNNIDX (the average S.D. for N-Ns for each 5-min interval in ms) and pNN50 (the proportion of successive N-N differences > 50 ms in percent) in the time domain, and very low (0.0033-0.04 Hz), low (0.04-0.15 Hz) and high (0.15-0.4 Hz) frequency power. Similar patterns of change in heart rate variability were seen when data for daytime and nighttime periods were analyzed separately. rMSSD (the root mean square successive difference of N-N intervals in ms), pNN50 and high frequency power are primarily indices of parasympathetic tone. SDNNIDX, and very low and low frequency power reflect both sympathetic and parasympathetic tone and longer term variability. Thus, moricizine decreases both vagal tone and longer term components of heart rate variability. This decrease produced by moricizine is similar to that reported with other type 1 antiarrhythmics.
我们研究了Ic类抗心律失常药物盐酸莫雷西嗪对心率变异性的影响。心率变异性降低是心肌梗死后及其他患者群体死亡的危险因素，一些抗心律失常药物会降低心率变异性。正常志愿者（10名男性，11名女性，年龄19 - 39岁）接受双盲安慰剂和盐酸莫雷西嗪治疗，剂量为200 mg，每日两次，共5天。在第4天，进行24小时心电图检查，并计算基于正常RR间期的心率变异性的时域和频域指标。莫雷西嗪降低了心率变异性的时域和频域指标。在时域中，SDNNIDX（每5分钟间隔的正常RR间期的平均标准差，单位为毫秒）和pNN50（连续RR间期差值>50毫秒的比例，单位为百分比）显著降低，以及极低频（0.0033 - 0.04 Hz）、低频（0.04 - 0.15 Hz）和高频（0.15 - 0.4 Hz）功率也显著降低。当分别分析白天和夜间的数据时，观察到心率变异性的类似变化模式。rMSSD（RR间期连续差值的均方根，单位为毫秒）、pNN50和高频功率主要是副交感神经张力的指标。SDNNIDX以及极低频和低频功率反映了交感神经和副交感神经张力以及更长时间的变异性。因此，莫雷西嗪降低了迷走神经张力以及心率变异性的长期成分。莫雷西嗪产生的这种降低与其他I类抗心律失常药物报道的情况相似。
