Blood pressure measurement 1049 3). Mutivariate logistic analysis showed that gender was significantly correlated with the discrepancy between PBP and CBP, only in group 1 (Exp(B)=2.158, p=0.04). Conclusion: In present study, central hemodynamics might affect the discrep- ancy between CBP and PBP. Also, gender difference was closely related with the discrepancy between CBP and PBP especially with normal CBP under 140mmHg. Not only CBP, the discrepancy between CBP and PBP should be considered for understanding the central hemodynamics. P5648 | BEDSIDE Central rate pressure product; new marker of cardiac load with exercise M. Kobayashi 1 , K. Oshima 1 , Y. Iwasaki 1 , Y. Kumai 1 , Y. Tsunoda 1 , M. Kino 1 , H. Kobayashi 1 , A. Yamashina 2 , K. Takazawa 1 . 1 Tokyo Medical University, Hachioji Medical Center, Tokyo, Japan; 2 Tokyo Medical University Hospital, Tokyo, Japan Background: The rate-pressure product (RPP) obtained by brachial cuff blood pressure has been used as the evaluation of the cardiac load at the exercise stress test. However, RPP of central blood pressure is thought to be a more direct measure of cardiac load. Methods: Treadmill exercise stress test was performed in 129 patients who were divided into 3 groups by age, younger (n=43, mean age 44±11y.o.), middle (n=43, mean age 63±3 y.o.) and older group (n=43, mean age 72±4y.o.). Patients were exercised to achieve 85% of age predicted maximum HR and symptoms limited using Bruce protocol. Brachial systolic blood pressure (bSBP), central systolic blood pressure (cSBP) and heart rate (HR) were measured by HEM-9000AI (Om- ron Healthcare) at rest and 1 minute after exercise. RPP was calculated by multi- plying SBP and HR. Results: There were not significant difference between bRPP and cRPP at rest in the 3 groups (younger, middle and older group, 9725±1922 and 9565±1954, 10035±2345 and 10067±2039, 10017±2034 and 10189±2127mmHg.bpm, p=0.70, 0.96, 0.74, respectively). Both bRPP and cRPP at rest in the 3 groups were also not significant difference (p=0.87 and 0.60). bRPP immediately after exercise was 17936±3490 with younger group, 18185±3609 with middle group and 18320±3082mmHg.bpm with older group, it was also not significant differ- ence (p=0.87). However, cRPP immediately after exercise was 15199±2647 with younger group, 15965±3231 with middle group and 16662±2569mmHg.bpm with older group. Figure 1 shows that cRPP immediately after exercise of older group was significantly higher than that of younger group (p<0.05). Figure 1. bRPP and cRPP Conclusion: Even if bRPP show the similar level, cRPP of older people after exercise are higher. Older people have a higher cardiac load after exercise, which is not readily assessed by bRPP. P5649 | BEDSIDE Effect of blood pressure variability on endothelial function assessed by brachial artery flow mediated dilatation S.I. Dumitrescu 1 , G. Cristian 1 , I. Tintoiu 1 , L. Chiriac 1 , V. Greere 1 , S. Stanciu 2 , D. Dragomir 3 , T. Nicolaescu 1 , R. Boingiu 1 , V.A. Voicu 4 . 1 ’Acad. Vasile Candea’ Emergency Clinical Center for Cardiovascular Diseases, Bucharest, Romania; 2 Clinical Emergency Central Military Hospital Dr. Carol Davila, Bucharest, Romania; 3 "Prof. Dr. Dimitrie Gerota" Emergency Hospital, Bucharest, Romania; 4 Romanian Academy, Bucharest, Romania Purpose: To examine the influence of blood pressure variability on endothelial function assessed by brachial artery flow mediated dilatation. Methods: We screened 190 individuals without history of cardiovascular dis- ease in a primary prevention program recording age (45,62±8,72 years), sex (48,4% males), body mass index (BMI = 27,03±4,79 kg/m 2 ), waist cir- cumference (94,42±14,16 cm), total cholesterol (214,30±41,87 mg/dl), LDL- cholesterol (136,59±37,73 mg/dl), HDL-cholesterol (47,99±13,24 mg/dl), triglyc- erides (150,02±108,15 mg/dl), blood glucose (92,28±28,18 mg/dl), number of smoked cigarettes/day. We determined the brachial artery FMD according to the guidelines for the ultrasound assessment of endothelial-dependent flow-mediated vasodilation. All subjects underwent a 24-hour Ambulatory Blood Pressure Mon- itoring (ABPM) on a working day, performing usual daily activities and avoiding heavy physical exercise. Blood pressure and heart rate readings were obtained every 15 minutes during daytime and every 30 minutes during nighttime. We recorded mean systolic and diastolic Blood Pressure (BP) and BP variability cal- culated as the Standard Deviation (SD) of mean blood pressure. After data collec- tion we investigated the correlations (Pearson’s r) between FMD values, "classi- cal" risk factors and ABPM records, defining the magnitude of correlation as weak (r = 0,1 to 0,3), moderate (0,3 to 0,5) and high (0,5 to 1). Results: The uppermost observed correlations of brachial artery FMD values were in the moderate range, with systolic BP variability (r=-0,399, p<0,001), mean systolic BP (r=-0,372, p<0,001) and waist circumference (r=-0,360, p<0,001). We found weak significant correlations between FMD and mean diastolic BP (r=- 0,288, p<0,001), age (r=-0,254, p<0,001), BMI (r=-0,290, p<0,001), number of smoked cigarettes/day (r=-0,223, p=002), HDL-cholesterol (r=0,168, p=0,021), triglycerides (r=-0,181, p=0,012) and blood glucose (r=-0,235, p=0,001). More- over, the persons with endothelial dysfunction defined as a brachial artery FMD value less than 7,5% have significantly increased systolic blood pressure variabil- ity as compared with those with normal endothelial function (14,29±3,41 mmHg vs. 11,48±2,40 mmHg, p<0,001). Conclusions: Our study indicates that systolic blood pressure variability deter- mined by ambulatory blood pressure monitoring is one of the most important factors that impacts on endothelial function. P5650 | BEDSIDE Comparison of cardiovascular mortality between patients with sustained normotension, white coat hypertension, masked hypertension and sustained hypertension in a clinical cohort B.K. Kim 1 , Y.G. Lee 2 , Y.H. Lim 2 , K.S. Kim 2 , J.H. Shin 2 . 1 Sung Ae General Hospital, Seoul, Korea, Republic of; 2 Hanyang University, Seoul, Korea, Republic of Purpose: Ambulatory blood pressure monitoring (ABPM) is increasingly used for various clinical purposes. After measurement of clinical blood pressure (BP) and ABPM, 3 groups of hypertensive patients were identified namely: white coat hypertensive patients (clinical BP were above limits, but ABPM were normal); masked hypertensive patients (clinical BP were normal, but ABPM were high); sustained hypertensive patients (both clinical and ABPM were high). The patho- physiology of these conditions are not exactly known. Besides there are only few studies that compare the 4 groups of patients together, especially in Korea. Thus the study was carried out to compare patients with sustained normotension (SN), white coat hypertension (WH), masked hypertension (MH), and sustained hyper- tension (SH). Methods: Our retrospective cohort study included 490 patients who underwent ABPM between 1994 and 1996 in the University Hospital, Seoul, Korea. All pa- tients also underwent history taking, physical examination, laboratory test. The follow-up period was 120 months. Results: In total 490 patients, 66 (13.5%) patients with SN, 121 (24.7%) patients with WH, 28 (5.7%) patients with MH, and 275 (56.1%) patients with SH were included. The frequency of CV mortality was 3.0% in SN, 7.4% in WH, 14.3% in MH, and 13.5% in SH. A Cox regression analysis found an interesting association between BP and CV mortality, after controlling for age, gender, diabetes mellitus, smoking and hypercholesterolemia. There was no difference in event rates be- tween MH and SH. Conclusions: Masked hypertension may be more frequent in clinical settings than in the population at large, and it is strongly associated with increased risk of CV mortality in Korea. Therefore, extensive use of Home BP and ABPM might be justified. However, further studies in large populations are needed to establish the effect of masked hypertension on cardiovascular mortality. P5651 | BENCH Prevalence of masked and isolated clinical hypertension in relation to the methodology of office blood pressure measurements: The ESTHEN study A. Coca 1 , J. Sobrino 2 , M. Domenech 1 , M. Camafort 1 , E. Vinyoles 3 , M.J. Adrian 4 , F. Gamazo 5 , F.J. Guerrero 6 on behalf of ESTHEN study investigators. 1 Hypertension and Vascular Risk Unit. Hospital Clinic, University of Barcelona, Barcelona, Spain; 2 Emergency Department. Hospital de l’Espirit Sant, Santa Coloma de Gramanet (Barcelona), Spain; 3 Primary Care Center La Mina, Barcelona, Spain; 4 Department of Internal Medicine. Hospital de l’Espirit Sant, Santa Coloma de Gramanet (Barcelona), Spain; 5 Department of Internal Medicine. Hospital de Medina del Campo, Medina del Campo (Valladolid), Spain; 6 Department of Internal Medicine. Hospital de Torrecárdenas, Torrecárdenas (Almería), Spain Aim: To investigate the number of office Blood Pressure (BP) readings that best correlate with 24-h ambulatory blood pressure monitoring (ABPM) to detect masked (MHT) and isolated clinical hypertension (ICH) Patients and methods: Observational, cross-sectional, multicenter study in treated hypertensive patients attended by Spanish hypertension units. After 5 minutes rest, six BP readings were performed at 1 minute intervals. 24-h ambula- Downloaded from https://academic.oup.com/eurheartj/article-abstract/34/suppl_1/P5649/410136 by guest on 09 June 2020