[Intracoronary isosorbide mononitrate versus placebo. A double-blind study with quantitative coronary angiography].

PURPOSE: To evaluate the vasodilation effect of intracoronary isosorbide mononitrate (ISMN) on the coronary arteries, systolic aortic pressure (SAP) and cardiac rhythms. METHODS: Forty patients aged 61 (40-72) years, 30 (75) male, were randomized to receive on a double blind fashion, 20 mg of ISMN or placebo. The two groups had similar baseline characteristics. Quantitative coronary arteriography [by cardiovascular measurement system (CMS)] and SAP were compared before and after ISMN. We also observed the cardiac rhythm. RESULTS: There were no arrhythmias. Reference vessel diameter increased from 2.6 +/- 0.5 mm before to 2.9 +/- 0.4 mm after ISMN and did not change, mean 2.9 +/- 0.5 mm, before and after placebo. There was a difference between ISMN and placebo (p