| Popis: |
The purpose of this work was to study interactions between physical properties of the arterial system and left ventricular performance during aging in normal and in hypertensive patients. 50 patients were studied; 28 normal patients (age range 22 to 68 years) and 22 patients with essential hypertension (age range 23 to 63 years). In hypertensive patients, the end systolic pressure-volume ratio (ESP/ESV), modulus of chamber stiffness (kp), left ventricular wall thickness (h), mass (m), m/LVEDV ratio (LVEDV: left ventricular end diastolic volume), systemic arterial resistance (SAR), pulse wave velocity (C) and characteristic impedance of the ascending aorta (Zc) were increased compared to normal subjects of similar age. The ejection fraction (EF), the mean velocity of fiber shortening (VCF) and dp/dt max were unchanged. In normal patients: the ESP/ESV ratio, kp, h, m, m/LVEDV ratio, SAR, C and Zc increased with age; there were no age related changes in EF, VCF or dp/dt max. In both groups, there was a close relationship between the m/LVEDV ratio and Zc, the characteristic impedance of the ascending aorta. These results suggest that: 1. aging and arterial hypertension lead to similar changes in the physical properties of the arterial system and in left ventricular performance; 2. in both cases, the development of concentric cardiac hypertrophy is closely related to the physical properties of the arterial system. |
