[Effects of slow-release isosorbide-5-mononitrate on ergometric parameters and cardiac output in stable effort angina...

The effects of a single oral dose of 60 mg of sustained release (R) isosorbide-5-mononitrate (ISM) administered in 9 male patients (mean age: 53 +/- 7 years) with stable exercise-induced angina pectoris were studied in a randomized, double blind, cross-over study. The effectiveness of the drug was evaluated by concomitant ergometer exercise stress test and cardiac output determination (bioimpedance method, Bomed Med-Ltd) performed 1 hour before and 1, 4, 10 and 24 hours after acute administration of placebo (P) and ISM-R. After P, all patients showed a positive exercise test, whereas 3 patients during ISM-R treatment had a negative exercise stress test 1 and 4 hours after ISM-R administration. Compared with P, ISM-R produced a statistically significant improvement of exercise stress test parameters at peak exercise (maximum work load, heart rate, systolic and diastolic blood pressures and double product) up to 10 hours after drug administration. On the other hand, cardiac output did not significantly differ at any time after ISM-R compared with both control conditions and P treatment. Moreover, no side effect was detected in any patient during the study. In conclusion, a single oral dose of 60 mg of sustained-release ISM-R seems to be an effective drug in the treatment of effort angina, its effectiveness lasting more than 10 hours without side effects.