The therapeutic value of clonidine in patients with coronary heart disease.

11 coronary patients, 8 with mild hypertension, were treated with clonidine, at a dose of 75 micrograms b.i.d. per os for a week. The effect of the drug on coronary heart disease was assessed by means of a symptom-limited multistage exercise test on the cycloergometer. Clonidine was effective in reducing the exercise-induced increases in blood pressure (by 15.5 +/- 6.1%), the double product (by 34.8 +/- 20.8%) and the electrocardiographic ischemic changes. In 2/4 patients, effort related ventricular extrasystoles were reduced by greater than 50% after clonidine. The drug worsened the anginal pain in 3 and relieved the pain in 3 patients. However, it reduced the exercise-induced ST-T segment downsloping in 7 patients. The tolerance was good, since only 3/11 patients reported slight dry mouth, sedation and pyrosis. In view of the electrocardiographic effect, further studies with clonidine on myocardial ischemia should be performed.