RESUMEN
In 50 patients with severe stable post-myocardial infarction angina grade III and IV of the N. Y. Heart Association, a calcium antagonist (niphedipine) was used in a double blind study with intercrossing. For the experimental design the same patient was his own control. The following criteria were used: number of bouts of angina, consumption of nitroglycerin pearls to control the angina, excercise test (Bruce technic), at the beginning and at the end of each treatment., Favourable results were observed in 36 of the 50 patients, in relation to the number of anginal crisis with a "p" value equal to 0.0062. In the effort capacity an improvement in relation to the basal conditions was observed with a "p" value less than 0.001. This shows a beneficial action of the drug with possible preferent actions on myocardial circulation.