INFLUENCE OF CENTRAL AND PERIPHERAL ARTERIAL STIFFNESS ON THE TIMING AND AMPLITUDE OF REFLECTED PRESSURE WAVE: PP.10.405

Abstract

Background: Central stiffness is known to be associated with increased pressure wave reflection, but the data about peripheral stiffness are scarce. Central stiffness is lower than peripheral in most subjects, but the reversal of central to peripheral stiffness gradient may occur at higher age and it may influence the mechanisms of wave reflection. Objective: To evaluate the relationships of central and peripheral arterial stiffness to the parameters of wave reflection. Methods: The study was performed in 528 subjects, aged 25 to 74 years and free of cardiovascular medication, who were selected randomly from general population (post-MONICA study). Pulse wave velocity on aorta (aoPWV) and on lower extremity (periphPWV) were measured by Sphygmocor. Wave reflections were assessed using carotid pulse waveform analysis. Results: Mean aoPWV and periphPWV were 7.3 and 11.1 m/s, respectively. There were 46 subjects with the reversal of stiffness gradient (aoPWV > periphPWV). They had markedly longer effective reflection distance (ERD; p < 0.001 in both sexes), but reflected wave transit time (RWTT) was not different; their carotid augmentation pressure (CAP) was higher in males (p < 0.01), but not in females. We further studied the simultaneous influence of central and peripheral stiffness on parameters of wave reflection in the whole population by means of multiple linear regression with adjustment on age, mean arterial pressure and heart rate. Except RWTT, aoPWV predicted highly significantly (p < 0.001) the parameters of wave reflection in both sexes, while periphPWV was only weakly positively associated with RWTT (p < 0.05 in both sexes), CAP in females (p < 0.01) and ERD in males (p < 0.05). Conclusions: Reversal of stiffness gradient was uncommon in our population-based sample. It was associated with prolongation of ERD, but the augmentation pressure was not decreased. These results do not confirm the hypothesis that the reversal is beneficial as it results in lower reflected wave*. When studied in a fully adjusted model, the contribution of muscular-type artery stiffness to the timing and amplitude of reflected wave was small. *Mitchell GF Hypertension 2004.