[Dose-response relationship of nitrate therapy of angina pectoris]

The treatment of 15 patients with coronary heart disease and exertion-related angina pectoris with isosorbide dinitrate (ISDN) tablets in 4 doses (6 X 5 mg, 6 X 20 mg, 6 X 40 mg, 6 X 80 mg) in a randomized sequence for 1 week each resulted in a dose-related improvement of ischemia (ST-segment depression during stress testing) as compared to placebo: 5 mg (30 mg/day): 24% (p less than 0.05); 20 mg (120 mg/day): 40% (p less than 0.05); 40 mg (240 mg/day): 60% (p less than 0.01); 80 mg (480 mg/day): 74% (p less than 0.01). Continuation of treatment for another 4 weeks with 480 mg/day led to a slight decrease in antianginal activity, with a 55% improvement of ST-depression. The frequency of angina pectoris was also lowered in a dose-related manner. For nitroglycerin in oral sustained release form (matrix system) a dose-related antianginal efficacy could be demonstrated in 12 patients enrolled in a double-blind cross-over trial: 2.6 mg (single dose): 23% (n.s.); 6.5 mg: 38% (p less than 0.01); 10 mg: 55% (p less than 0.001); 20 mg: 74% (p less than 0.0001). The duration of action of 20 mg was 4 hours. Transdermal nitroglycerin also proved to be effective in a dose related fashion. In 12 patients undergoing 1-week treatment periods with 5 cm2, 10 cm2 and 20 cm2-patches ST-depression was favourably influenced by 15% (n.s.), 22% (p less than 0.05) and 46% (p less than 0.001) 3 hours after administration. No antiischemic efficacy was demonstrable 24 hours after medication.(ABSTRACT TRUNCATED AT 250 WORDS)