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 measured before and 10 min after 10 mg of nifedipine was given sublingually 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 catheterization of the ascending aorta. At baseline, aortic distensibility was lower in patients with coronary artery disease compared with control (0.922 +/- 0.367 vs 2.456 +/- 0.588 10(-6).cm2.dyn-1, respectively, p < 0.001). After nifedipine administration, aortic distensibility increased significantly both in normal subjects (by 0.812 +/- 0.316 10(-6).cm2.dyn-1-36.5 +/- 19 percent; p < 0.001) and in patients with coronary artery disease (by 0.296 +/- 0.203 10(-6).cm2.dyn-1-36.6 +/- 28.2 percent; p < 0.001). These results indicate that nifedipine administration increases aortic distensibility in both normal subjects and patients with coronary artery disease.