ASSESSMENT OF SEGMENTAL VISCOELASTIC PROP ERTIES COMPARING NORMOTENSIVE PATIENTS WITH TREATED ESSENTIAL HYPERTENSIVE PATIENTS

Local elastic properties of the descending aorta at different levels w ere evaluated derived from intravascular ultrasound images and pressur e measurements. For this purpose 30 normotensive subjects (NBP) and 30 age matched, medically treated patients with essential hypertension ( EH), who underwent diagnostic cardiac catheterization were studied. Al though the diastolic blood pressure showed no significant difference, in EH the continuous loss of volume compliance with increasing distanc e from the heart was significantly higher (1.45+/-0.19 10(-10) m(5)/at the thoracic aorta compared to 0.08 +/- 0.05 10(-10) m(5)/N at the ex ternal iliac artery in NBP vs. 0.81+/-0.09 10(-10) m(5)/N and 0.05+/-0 .01 10(-10) m(5)/N at corresponding sites in EH), indicating changing vessel wall structure along the aortic tree. Although only systolic bu t not diastolic blood pressure of EH was not significantly different f rom that of NBP viscoelastic parameters of the aortic wall remained al tered. Normalization of high blood pressure by long-term antihypertens ive treatment may not fully reverse changes in viscoelastic properties of the arterial wall caused by arterial hypertension.