P343 Evaluation of the age-related reference values of aortic pulse wave velocity in healthy subjects using Doppler echocardiography

Introduction Aortic pulse wave velocity (aPWV) is a measure of aortic stiffness, which is an indicator of vascular aging and has established independent prognostic role in predicting cardiovascular complications. aPWV can be measured with various non-invasive methods, but with different reference values depending on the technique used. The Doppler echocardiography method is potentially widely accessible and has been recently showed to have high correlation with invasive reference method of aPWV based on intraarterial pressure evaluation. Purpose The aim of the study was to establish reference values of aPWV, measured by Doppler method during a standard echocardiography in healthy subjects. Methods 121 healthy adults, normotensive, non-smoking, without chronic diseases and not taking medication, were included. All the patients were divided into 5 groups due to age criterion (D1-age 21-30 yrs., n = 33; D2-age 31-40 yrs., n= 23; D3-age 41-50 yrs., n = 26; D4-age 51-60 yrs., n = 22; and D5-age 61-70 yrs., n = 17). During a routine echocardiographic examination with a cardiac probe, standard echocardiographic and anthropometric parameters were acquired. Additionally, 10 Doppler waveforms were recorded in the distal aortic arch and then in the left external iliac artery. The transit time was calculated as a difference between time delay of the two points of the Doppler recordings relative to ECG signal. The distance between proximal and distal points was measured over the body surface using a flexible measuring tape. aPWV values were calculated according to the formula: PWV = distance/transit time. Results The mean age of the studied group was 42 ± 13 yrs., BMI 24.5 ± 3.4, SBP 123 ± 10.39 mm Hg, DBP 76.98 ± 6.53 mm Hg, HR 64 ± 10 bpm. aPWV 5.28 ± 1.07; LVEDD 4.6 ± 0.4 cm; LA 3.65 ± 0.33 cm; aorta 3.26 ± 0.38 cm; LVMI 87.12 ± 15.00 g/m2. In the studied subjects, aPWV did not differ according to sex (females, n = 53, aPWV 5.38 ± 1.21 m/s vs. males, n = 68, aPWV 5.21 ± 0.94 m/s, p = 0.37). In the multivariate linear regression analysis only age and SBP were independently associated with aPWV, but none of the echocardiographic parameters studied. Mean aPWV values with 95% confidence interval (95%CI) for each decade of life were recorded as follows: D1-age 21-30, aPWV 4.56 m/s (95%CI 4.41 to 4.72), D2-age 31-40, aPWV 4.65 m/s (95%CI 4.37 to 4.94), D3-age 41-50, aPWV 5.15 m/s (95%CI 4.88 to 5.43), D4-age 51-60, aPWV 5.96 m/s (95%CI 5.54 to 6.38), D5-age 61-70, aPWV 6.88 m/s (95%CI 6.42 to 7.34). Conclusions We report age-related values of aPWV in a healthy population measured by Doppler echocardiography method. This may be helpful in future research exploring the associations between aortic stiffness, cardiac function and cardiovascular prognosis in a large population of patients referred for echocardiography.