The treatment of exercise-inducible chronic stable angina with diltiazem. Effect on treadmill exercise

Although diltiazem has been shown to alleviate vasospastic angina pectoris, its effect on exercise-inducible chronic stable angina has not been objectively studied. Accordingly, the effect of diltiazem was studied in this condition with a placebo controlled double-blind randomized cross-over protocol at three dose levels (120, 180 and 240 mg/day) during graded treadmill exercise. Three end-points were evaluated: 1) time to onset of angina or fatigue if angina were eliminated; 2) time to 1 mm ST segment depression or fatigue if ST depression were eliminated; and 3) time to termination of exercise (2+ angina or fatigue). All end-points were prolonged at all dose levels. At the highest dose of 240 mg/day, time to onset angina or termination was prolonged from a placebo time of 8.0 +/ 0.9 to 9.8 +/- 0.9 minutes (p = < .001); time to ST depression or termination was prolonged from 7.8 +/- 0.9 to 9.1 +/- 0.8 minutes (p = .007); and time to termination was prolonged from 9.9 +/- 0.9 to 10.8 +/- 0.8 minutes (p = .02).