Concomitant calcium antagonist plus isosorbide dinitrate therapy for markedly active variant angina

Abstract

The present study was performed to assess the efficacy of concomitant calcium antagonist/isosorbide dinitrate therapy in patients with frequent episodes of variant angina and to compare such combination therapy with isosorbide dinitrate alone. We enrolled nine such patients (six men and three women, aged 47 ± 9 [mean ± standard deviation] years) in a long-term comparison of (1) oral isosorbide dinitrate (117 ± 63 mg per day) alone, (2) verapamil (453 ± 75 mg per day) + isosorbide dinitrate (given in the same dose as stated above), and (3) nifedipine (71 ± 14 mg per day) + isosorbide dinitrate (also given in the same dose as stated), each administered for 2 months. During isosorbide dinitrate therapy, these nine patients averaged 23.7 ± 37.3 chest pains per week, consumed 24.4 ± 47.4 sublingual nitroglycerin tablets per week, and demonstrated 46.5 ± 43.2 episodes per week of transient ST segment deviations on calibrated two-channel Holter monitoring. During therapy with verapamil/isosorbide dinitrate and nifedipine/isosorbide dinitrate, the frequency of angina and ST segment deviations was dramatically reduced (verapamil/isosorbide dinitrate, 3.9 ± 3.6 chest pains per week and 3.5 ± 2.6 ST segment deviations per week, p < 0.05; nifedipine/isosorbide dinitrate, 3.1 ± 4.0 chest pains per week and 5.5 ± 6.6 ST segment deviations per week, p < 0.05). In all respects, verapamil/isosorbide dinitrate and nifedipine/isosorbide dinitrate were similar to one another. Thus, in patients with very frequent episodes of variant angina, a calcium antagonist/isosorbide dinitrate combination is much more effective than isosorbide dinitrate alone in reducing the frequency of angina and ischemic ECG alterations.