Humen D P, Kostuk W J
Walter MacKenzie Centre, University of Alberta, Edmonton.
Can J Cardiol. 1991 Mar;7(2):74-80.
Twenty-four patients were randomized to a double-blind, triple placebo controlled, latin square protocol to examine the relative efficacy of propranolol or diltiazem given as monotherapy or in combination with isosorbide dinitrate. Treatment phases were preceded and followed by placebo control periods. At the end of each phase, symptom-limited treadmill exercise stress tests were performed, as well as rest and exercise radionuclide ventriculography. Both forms of monotherapy were effective in reducing episodes of angina and nitroglycerin use, and in improving exercise tolerance. Diltiazem monotherapy was associated with slightly higher treadmill times (509.9 +/- 123 s) compared to propranolol (462.7 +/- 131 s, P less than 0.05). The addition of isosorbide dinitrate to either form of monotherapy allowed no further improvement in any of the measured clinical responses. Radionuclide ventriculography showed no significant difference in resting left ventricular function. The addition of isosorbide dinitrate to propranolol showed a reduction in end diastolic volume in keeping with a reduction in preload. In response to exercise, stress-induced left ventricular dysfunction was equal in all groups except for the diltiazem-nitrate combination, which was associated with a higher ejection fraction (56.2 +/- 8.6%) compared to monotherapy (52.6 +/- 10.9%, P less than 0.01). A higher cardiac output could be achieved in the groups treated with diltiazem; this was related to increased heart rate and maintenance of stroke volume. It was concluded that diltiazem is equally effective as propranolol for the treatment of chronic stable angina and, in terms of exercise capacity and cardiac output, superior to beta-blockade. The addition of isosorbide dinitrate appears to impart no overt benefits, but some evidence suggests a reduction in left ventricular decompensation in the face of stress.
24名患者被随机分配至双盲、三联安慰剂对照、拉丁方试验方案，以研究普萘洛尔或地尔硫䓬单药治疗或与硝酸异山梨酯联合使用的相对疗效。治疗阶段前后均有安慰剂对照期。在每个阶段结束时，进行症状限制的平板运动应激试验以及静息和运动放射性核素心室造影。两种单药治疗形式均能有效减少心绞痛发作次数和硝酸甘油使用量，并提高运动耐量。与普萘洛尔（462.7±131秒，P<0.05）相比，地尔硫䓬单药治疗的平板运动时间略长（509.9±123秒）。在任何一种单药治疗中添加硝酸异山梨酯均未使任何测量的临床反应进一步改善。放射性核素心室造影显示静息左心室功能无显著差异。在普萘洛尔中添加硝酸异山梨酯显示舒张末期容积减少，与前负荷降低一致。运动时，除地尔硫䓬-硝酸酯联合组外，所有组应激诱导的左心室功能障碍相同，地尔硫䓬-硝酸酯联合组与单药治疗相比，射血分数更高（56.2±8.6%）（52.6±10.9%，P<0.01）。地尔硫䓬治疗组可实现更高的心输出量；这与心率增加和维持每搏输出量有关。得出的结论是，地尔硫䓬在治疗慢性稳定型心绞痛方面与普萘洛尔同样有效，就运动能力和心输出量而言，优于β受体阻滞剂。添加硝酸异山梨酯似乎没有明显益处，但一些证据表明在应激情况下可减少左心室失代偿。
