Abstract 11903: Assessment of Left Ventricular Relaxation Time by Pulse Wave Analysis: Association With Arterial Compliance

Abstract

Introduction: The long left ventricular relaxation (LVR) has been shown as a marker of diastolic dysfunction. This parameter is usually measured by such complex methods as echocardiography and radionuclide technique. This study tests a possibility to evaluate LVR time by applanation tonometry and explores its association with arterial distensibility basing on the assumption of a parallelism in contractile mechanics between striated cardiac muscle and arterial smooth muscle. Methods: Overall, 352 normotensive subjects (age 18-76 yrs.) were enrolled in this study. The LVRT was assessed by pulse wave analysis (SphygmoCor) and measured as difference between the end of systole (ejection duration point, ED, corresponding to the closure of aortic valve) and the time of peak pressure (T1, figure) generated by systolic antegrade wave in aortic root (LVRT,%=(ED-T1)/Tf*100). Intima-media thickness of brachiocephalic arteries and heart dimensional indices were measured by ultrasonography. Results: A difference was established in LVRT between age-matched female (47.9 yr., 24.8±2.8 %, M±SD, n=158) and male groups (47.1 yr., 21.7±2.9 %, n=192, p<0.001, T-test). In men, LVRT was associated with age (r=0.33), end systolic volume (partial r=0.39; age and HR= const.), augmentation index (AIx@75, r=0.33), aorta-to-radial pulse pressure amplification (r=-0.24), and time to reflection wave (r=-0.25, two-sided p<=0.001 for all cases). The association of LVRT with AIx remains significant after adjusting for age, Tf, and SBP in multiple regression analysis (GLM module, SPSS). In women, less pronounced associations were found. No relations were seen of LVRT with intima-media thickness of brachiocephalic arteries and carotid-radial pulse wave velocity in both sex groups. Conclusions: In healthy subjects, the long LVR assessed by PWA was associated with stiff conduit arteries of upper limbs. Figure . Pulse pressure profile in the aortic root as a result of pulse wave analysis