Posma J L, van Dijk R B, Lie K I
Department of Cardiology, University Hospital Groningen, The Netherlands.
Eur Heart J. 1989 Oct;10(10):923-7. doi: 10.1093/oxfordjournals.eurheartj.a059403.
The efficacy of sustained-release diltiazem (diltiazem-SR) 120 mg b.i.d. was compared with metoprolol 100 mg b.i.d. in 12 patients with stable angina. Following a 1-week placebo period, patients received diltiazem-SR or metoprolol in two 3-week treatment periods, in a randomized double-blind crossover design. Total exercise time was increased more with diltiazem-SR than with metoprolol (1.2 min vs 0.4 min, P = 0.02), although the reduction in frequency of weekly anginal attacks was equal with both drugs (5 +/- 3 with placebo to 1 +/- 1 with both drugs). The difference between diltiazem-SR and metoprolol may, in part, be due to the fact that the tests were performed 12 h after drug administration. The diltiazem plasma levels were in the therapeutic range; metoprolol plasma levels, in contrast, were all below the therapeutic range. In addition, the patients might be tired out earlier during beta-blockade therapy, because a greater increase in exercise time with diltiazem-SR compared with metoprolol was found in those patients in whom the exercise endpoint changed from angina to fatigue. Thus, diltiazem-SR effectively reduces the frequency of anginal attacks when given twice daily, and improves exercise capacity to a greater extent than metoprolol 12 h after last dose.
在12例稳定型心绞痛患者中，比较了缓释地尔硫䓬（地尔硫䓬缓释片）每日两次、每次120毫克与美托洛尔每日两次、每次100毫克的疗效。在为期1周的安慰剂期后，患者采用随机双盲交叉设计，在两个为期3周的治疗期内分别接受地尔硫䓬缓释片或美托洛尔治疗。与美托洛尔相比，地尔硫䓬缓释片使总运动时间增加更多（1.2分钟对0.4分钟，P = 0.02），尽管两种药物使每周心绞痛发作频率的降低程度相同（安慰剂组为5±3次，两种药物治疗组均为1±1次）。地尔硫䓬缓释片与美托洛尔之间的差异可能部分归因于测试在给药后12小时进行这一事实。地尔硫䓬血浆水平处于治疗范围内；相比之下，美托洛尔血浆水平均低于治疗范围。此外，在β受体阻滞剂治疗期间患者可能更早感到疲惫，因为在那些运动终点从心绞痛转变为疲劳的患者中，与美托洛尔相比，地尔硫䓬缓释片使运动时间增加得更多。因此，地尔硫䓬缓释片每日给药两次时可有效降低心绞痛发作频率，且在末次给药12小时后比美托洛尔更大程度地改善运动能力。
