DISTENSIBILITY OF THE ASCENDING AORTA IN CORONARY-ARTERY DISEASE AND CHANGES AFTER NIFEDIPINE ADMINISTRATION

To study the effect of nifedipine on aortic distensibility in patients with coronary artery disease, ascending aorta distensibility was meas ured before and 10 min after 10 mg of nifedipine was given sublinguall y in 13 patients with coronary artery disease and 12 control subjects. Aortic distensibility was calculated as a function of changes in the aortic diameter and pulse pressure. Aortic diameters were measured by echocardiography and aortic pressures were measured directly by cathet erization of the ascending aorta. At baseline, aortic distensibility w as lower in patients with coronary artery disease compared with contro l (0.922 +/- 0.367 vs 2.456+/-0.588 10(-6).cm(2).dyn(-1) respectively, p<0.001). After nifedipine administration, aortic distensibility incr eased significantly both in normal subjects (by 0.812+/-0.316 10(-6).c m(2).dyn(-1)-36.5+/-19 percent; p<0.001) and in patients with coronary artery disease (by 0.296+/-0.203 10(-6).cm(2).dyn(-1)-36.6+/-28.2 per cent; p<0.001). These results indicate that nifedipine administration increases aortic distensibility in both normal subjects and patients w ith coronary artery disease.