[Interval therapy in effective treatment of angina pectoris using nitroglycerin patch systems. A controlled study with determination of nitroglycerin plasma levels].
In ten patients with angiographically-documented coronary artery disease, stable angina pectoris and reproducible exercise-induced ST-segment depression, the extent and duration of antiischemic and antianginal effects of transdermal nitroglycerin patches delivering 10 mg/24 hours were investigated according to a double-blind, crossover, placebo-controlled protocol. Exercise testing and blood sampling for determination of nitroglycerin plasma concentrations were carried out at 2.5 and twelve hours after initial application, at 2.5, twelve and 24 hours after renewed application subsequent to a twelve-hour treatment pause as well as at 2.5 hours after application of a third patch (Figure 1). At 2.5 hours after initial application there was a reduction in exercise-induced ST-segment depression from 2.7 mm +/- 0.19 (SEM) to 0.75 +/- 0.2 (-72%; p less than 0.001) (Figure 2). The exercise capacity to onset of 1 mm ST-segment depression increased from 117 Watt X min +/- 34 (SEM) to 361 Watt X min +/- 84 (+210%; p less than 0.001) (Figure 3). At twelve hours, exercise-induced ST-segment depression was reduced only from 2.5 mm +/- 13 to 1.77 +/- 0.2 (-32%; p less than 0.01) and the increase in exercise capacity to onset of 1 mm ST-segment depression was narrowed from 136 Watt X min +/- 28.5 to 215 Watt X min +/- 43 (+59%; p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)