P57 ASSESSMENT OF PULSE WAVE VELOCITY AND ASSOCIATION TO TARGET ORGAN DAMAGE IN TREATMENT-NAïVE HYPERTENSIVE PATIENTS: A COMPARISON OF SPHYGMOCOR AND MOBIL-O-GRAPH

Abstract

Introduction: Comparison of Mobil-O-Graph® with SphygmoCor® exclusively in treatment- naïve hypertensives has never been done. Aims of the study were to assess 1) intra- device agreement between both methods, 2) inter-device agreement between two surface measurements of SC (subtracted distance (cfPWVsub)) and direct distance × 0.8 (cfPWV0.8)) with two patient’s positions of MG (supine (supPWVestim)) and sitting (sitPWVestim)), 3) the strength of association between tonometric and oscillometric measures of PWV with target organ damage (TOD). Methods: Cross-sectional, observational study in 171 consecutive, treatment-naïve subjects derived to a Hypertension Unit with suspected hypertension. Standard echocardiography, ECG, carotid ultrasound and laboratory tests were performed. Results: Mean age was 49.7 years, 57.3% were women. Reproducibility: Mean differences (±SD of the difference (SDD)) between duplicate SC and MG PWV measurements were non-significant. Agreement: cfPWV0.8 yielded the highest PWV values (8.17±1.6 m/s), followed by cfPWVsub (7.98±1.7 m/s), supPWVestim (7.83±1.7 m/s) and sitPWVestim (7.80±1.6 m/s). We observed significant mean differences only between cfPWV0.8 and all other PWV measures: with cfPWVsub (0.23 m/s, p = 0.001), with sitPWVestim (0.39 m/s, p = 0.001) and with supPWVestim (0.38 m/s, p = 0.002). No significant correlation was found between the mean and the difference for PWV in any comparison. Association with cardiac damage was highest with cfPWVsub, supPWVestim and sitPWVestim were more closely related to carotid damage, though differences were not significant. Comparison of PWV Mean difference CI p cfPMVsub–supPWVestim 0,16 −0,06/0,37 0,149 cfPWVsub–sitPWVestim 0,18 −0,034/0,39 0,098 cfPWV0.8–supPWVestim 0,38 0,15/0,62 0,002 cfPWV0.8–sitPWVestim 0,39 0,15/0,63 0,001 cfPWV0.8–cfPWVsub 0,23 0,12/0,35 0,000 supPWVestim–sitPWVestim 0,02 −0,07/0,12 0,635 cfPWV0.8: direct distance x 0.8-based carotid-femoral PWV. cfPWVsub: subtracted distance-based carotid-femoral PWV. sitPWVestim: estimated aortic PWV in sitting position. supPWVestim: estimated aortic PWV in supine position. Table 3.Differences between PWV measured by applanation tonometry according to two surface measurements and by brachial oscillometry according to supine ox sitting position. Conclusions: SC and MG showed similar and acceptable reproducibility. SC and MG were interchangeable only using subtracted distance (cfPWVsub), while direct distance x 0.8 showed significantly higher PWV values. Association to TOD was significant and similar between SC and MG.