Ekelund L G, Johnsson G, Melcher A, Oro L
Am J Cardiol. 1976 Mar 31;37(4):630-4. doi: 10.1016/0002-9149(76)90406-9.
The interaction between cedilanid-D and metoprolol, a selective beta receptor blocking agent, on exercise tolerance and systolic intervals was studied in 15 patients with angina pectoris. The patients had been treated with metoprolol for several months in a dose of 50 mg, three times daily (one patient received 25 mg three times daily). Each patient participated in two studies separated by at least 1 week. After arriving at the laboratory each received 50 mg of metoprolol orally; thereafter, either cedilanid-D or placebo was infused intravenously in a double-blind study performed in randomized order. When the effect of the drugs was maximal, the systolic intervals and the heart volume were recorded at rest, and the exercise tolerance was tested with a bicycle ergometer. The mean maximal value of plasma concentrations of metoprolol assessed during the study was about 50 ng/ml but the variation among subjects was great (20 to 187 ng/ml). After administration of cedilanid-D there was a shortening of the pre-ejection period and left ventricular ejection time compared with results after placebo; the reduction was similar to that found after administration of cedilanid-D without beta blocking drugs. The total heart volume decreased by an average of 55 ml, but the individual variation was great. The patients' average work capacity, expressed as total work, was not altered by cedilanid-D when compared with results after placebo. No relation was found between initial heart size and the effect of cedilanid-D on capacity for physical work. It therefore appears that there is no indication for the routine use of digitalis during beta blocking therapy in patients with angina pectoris who do not have cardiac failure.
在15例心绞痛患者中研究了西地兰-D与选择性β受体阻滞剂美托洛尔对运动耐量和收缩期时限的相互作用。这些患者接受美托洛尔治疗数月，剂量为50mg，每日3次（1例患者每日3次接受25mg）。每位患者参与两项研究，间隔至少1周。到达实验室后，每位患者口服50mg美托洛尔；此后，在一项随机顺序进行的双盲研究中静脉输注西地兰-D或安慰剂。当药物作用达到最大时，记录静息时的收缩期时限和心脏容积，并用自行车测力计测试运动耐量。研究期间评估的美托洛尔血浆浓度的平均最大值约为50ng/ml，但个体间差异很大（20至187ng/ml）。与安慰剂给药后的结果相比，给予西地兰-D后射血前期和左心室射血时间缩短；这种缩短与未使用β受体阻滞剂而给予西地兰-D后的情况相似。心脏总体积平均减少55ml，但个体差异很大。与安慰剂给药后的结果相比，西地兰-D未改变患者以总功表示的平均工作能力。未发现初始心脏大小与西地兰-D对体力工作能力的影响之间存在关联。因此，对于没有心力衰竭的心绞痛患者，在β受体阻滞剂治疗期间似乎没有常规使用洋地黄的指征。
