Comparison between isosorbide dinitrate in aerosol and in tablets for the treatment of hypertensive emergencies

Sixty patients with a hypertensive emergency (mean arterial pressure >130 mm Hg and evidence of target organ damage) were randomly divided into two groups of 30 patients each. Group A received 1.25 mg of isosorbide dinitrate aerosol upon arrival and a second dose 15 minutes later when the mean arterial pressure reduction was < 15%. Group B received a single 5 mg tablet of sublingual isosorbide dinitrate. Electrocardiography was performed in both groups prior to and 30 minutes after the medication. Blood pressure was monitored for 6 hours. Blood pressure in Group A patients decreased in an average time of 10 minutes from 191 +/- 12/122.3 +/- 5 to 151.5 +/- 9.2/93 +/- 4 mm Hg, p < 0.005. Mean arterial pressure decreased by 22.8%: 145 +/- 7 to 112 +/- 7.5 mm Hg, p < 0.005. No adverse effects occurred. Five patients in Group B did not respond; in the rest of the group blood pressure decreased 45 minutes after receiving the medication from 194 +/- 8/125 +/- 5.5 to 160 +/- 11/98 +/- 6 mm Hg; p < 0.005. Mean arterial pressure decreased by 20.1%: 148.3 +/- 12 to 118.6 +/- 9 mm Hg, p < 0.002; ten patients suffered headache. Three patients in Group A had a subepicardial lesion in the first electrocardiograph, which disappeared with the use of the aerosol. In Group B, electrocardiography results were normal. These results seem to indicate that isosorbide dinitrate aerosol is better than tablets for the treatment of patients with a hypertensive emergencies.