[Comparative evaluation of the clinical effectiveness and the adverse effects of three different forms of nitrates in high oral doses in patients with stable angina pectoris].

Unlabelled: The aim of this study was the comparative evaluation of antianginal efficacy and the adverse effects of 3 nitrates in oral doses: isosorbide dinitrate 80 mg in slow release form (ISDN-80), nitroglycerin 15 mg--slow release (NITRO-15) and pentaerythritol tetranitrate 100 mg in normal tablets (PENTA-100) in patients (pts) with stable angina pectoris. In a randomized, double-blind, cross-over and placebo (P) controlled study 15 men, with mean age 54.8 +/- 8.0 years, with stable angina, received single doses of: ISDN-80, NITRO-15, PENTA-100 or P. Clinical efficacy of the drugs was evaluated by analysis of the walking times: total (TT), to angina (TA), and to ischemia (TI) on treadmill during stress tests performed 2 and 6 hours (h) after drug ingestion; the adverse effects were registered during 6 h follow up.

Results: 2 h after ingestion all 3 study drugs improved significantly: TT, TA and TI in comparison to P. After 6 h the same parameters were improved by: ISDN-80 and NITRO-15, but PENTA-100 improved only TT and TA. After 6 h ISDN-80 significantly improved in comparison to NITRO-15: TT by 19.7% (p < 0.01), TA by 21.2% (p < 0.01) ant TI by 25.0% (p < 0.05), and in comparison to PENTA-100: TT by 32.1% (p < 0.001), TA by 33.4% (p < 0.001) and TI by 41.1% (p < 0.01). After 6 h NITRO-15 significantly improved TI in comparison to PENTA-100 by 13.1% (p < 0.05). The headaches, the most frequent adverse effects, occurred after ingestion of ISDN-80 in 6 pts, NITRO-15 in 4 pts, PENTA-100 in 3 pts and P in 1 pt. Among three evaluated nitrates ISDN-80 significantly improved the effort tolerance and the coronary reserve in the strongest way, NITRO-15 was intermediate in the clinical efficacy, but PENTA-100, the drug with the weakest antianginal efficacy, was the reason of the least number of the adverse effects.