LEFT VENTRICULAR EJECTION TIME MORE THAN HEART RATE IS AN INDEPENDENT DETERMINANT OF AORTIC PULSE WAVE VELOCITY

Background: An increased carotid-femoral pulse wave velocity (PWV) is marker of vascular disease and predictor of mortality in various clinical conditions. However, it is a composite index depending on structural changes related to pressure load and atherosclerosis, but also influenced by functional mechanisms including heart rate (HR), to be taken in account when using PWV as surrogate end-point of atherosclerotic disease. Aim of this study was to evaluate the impact of HR upon PWV through a wide age range, and to verify the role of the two components of the heart period (HP), LV ejection time (LVET) and diastolic time (DT). Methods: Carotid pulse wave analysis (PWA) and carotid-femoral PWV were determined by tonometer (Pulsepen) in 3,020 subjects (1,107 males and 1,913 females, age range 15–105 years). HP, LVET and DT were obtained by PWA. PWV was estimated by sequential recordings at carotid and femoral artery level. Results: PWV increased significantly (p 45 years, male sex, MBP and HP were independent determinants of PWV (cumulative R2 = 0.27). Replacing HP with LVET, but not with DT, improved the power of the model. In subjects <45 years only MBP, sex and age resulted determinants of PWV. Adding LVET but not HP or DT improved significantly the model and made no more significant the role of age. Conclusion: LVET is an independent factor determining PWV stronger than HR or DT and steady during the life. Age remains the strongest predictor of PWV in subjects >45 years, while it is replaced by LVET in the young. In clinical practice and research, LVET should be taken into account when interpreting PWV variability, and PWV values adjusted for LVET more than for HR