美托洛尔和硝苯地平对无症状性心肌缺血的疗效观察

采用随机双盲交叉的方法，对４６例动态心电图监测证实为无症状性心肌缺血的冠心病患者，观察美托洛尔和硝苯地平的抗缺血作用。结果发现，这两类药物对减少无症状性心肌缺血发作的平均数量和时间均有效，但以美托洛尔最明显，两组间比较有极显著性差异（Ｐ＜０．００１），而且美托洛尔抗缺血的持续时间长于硝苯地平。因此，美托洛尔可作为无症状性心肌缺血的首选药物。

ANTI-ISCHEMIC EFFECTS OF METOPROLOL IN PATIENTS WITH SILENT MYOCARDIAL ISCHEMIA

The anti-ischemic effects of metoprolol (50 mg,QD, 8 wks, n=23) and nifedipine(10 mg,tid, 8 wks, n=23) were compared in a randomized doubleblind crossover study in patients with coronary artery disease and transient silent ischemia during ambulatory electrocardiographic monitoring.The results showed that 512 transient episodes of ST depression were detected, 385 of the total were asymptomatic (75.20%).There were no statistically significant differences in heart rate and the product of heart rate and systolic blood pressure before ST depression between asymptomatic and symptomatic episodes. The heart rates at the time of maximal ST depression during both asymptomatic and symptomatic ischemia increased by 14 and 24 beats/min respectively over those before ST depression (p<0.001).The increase of products of heart rate and systolic blood pressure at the time of maximal ST depression during asymptomatic and symptomatic ischemia were 20 and 44, respectively over those before ST depression (p<0.001). Both metoprolol and nifedipine were effective in reducing the average number and duration of transient ischemic events, but therapy with metoprolol was associated with a significantly greater reduction in the mean number and duration of silent ischmic events(p<0.001).