Gianfranco Parati

Relationship of 24-hour Blood Pressure Mean and Variability to Severity of Target-organ Damage in Hypertension

Casual blood pressure (BP) can predict the development of cardiovascular morbidity and mortality, but the correlations between its values and the subsequent occurrence of such complications are low. This may depend on different individual resistance to the damage produced by hypertension. However, it may also depend on the recognized inability of causal BP to reflect accurately the 24-h mean and profile BP. In order to test the latter hypothesis, 24-h BP was recorded intra-arterially (Oxford method) in 108 hospitalized subjects with essential hypertension ranging from mild to severe. The 24-h means and standard deviations (i.e. variabilities) for systolic, mean and diastolic BP obtained by computer analysis of the BP tracing were related to the rate and severity of target-organ damage (TOD) assessed by clinical examination and quantified according to a predetermined score. The results confirmed that 24-h BP may be variably different from cuff BP among subjects. For nearly any value of cuff BP, subjects in whom the 24-h mean BP was low had a lower prevalence and severity of TOD than those in whom the 24-h mean BP was high (P less than 0.01). Furthermore, for nearly any level of 24-h mean BP, subjects in whom the 24-h BP variability was low had a lower prevalence and severity of TOD than those in whom the 24-h BP variability was high (P less than 0.05). These findings demonstrate that the severity of hypertension is more closely related to 24-h mean BP than to cuff BP values.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparison of finger and intra-arterial blood pressure monitoring at rest and during laboratory testing.

The accuracy of blood pressure values obtained by continuous noninvasive finger blood pressure recording via the FINAPRES device was evaluated by comparison with simultaneous intraarterial monitoring both at rest and during performance of tests known to induce fast and often marked changes in blood pressure. The comparison was performed in 24 normotensive or essential hypertensive subjects. The average discrepancy between finger and intra-arterial blood pressure recorded over a 30-minute rest period was 6.5±2.6 mm Hg and 5.4±2.9 mm Hg for systolic and diastoiic blood pressure, respectively; a close between-method correspondence was also demonstrated by linear regression analysis. The beat-to-beat changes in finger systolic and diastoiic blood pressure were on average similar to those measured intra-arterially during tests that induced a pressor or depressor response (hand-grip, cold pressor test, diving test, Valsalva maneuver, intravenous injections of phenylephrine and trinitroglycerine) as well as during tests that caused vasomotor changes without major variations in blood pressure (application of lower body negative pressure, passive leg raising). The average between-method discrepancy in the evaluation of blood pressure changes was never greater than 4.3 and 2.0 mm Hg for systolic and diastoiic blood pressure, respectively; the corresponding standard deviations ranged between 4.6 and 1.6 mm Hg. Beat-to-beat computer analysis of blood pressure variability over the 30-minute rest period provided standard deviations almost identical when calculated by separate consideration of intra-arterial and finger blood pressure tracings (3.7 and 3.8 mm Hg, respectively). The two methods of blood pressure recording also allowed similar assessments of the sensitivity of baroreceptor control of heart rate (vasoactive drug injections) and blood pressure (neck chamber technique) to be obtained. Thus, beat-to-beat blood pressure recording via FINAPRES provides an accurate estimate of means and variability of radial blood pressure in groups of subjects and represents in most cases an acceptable alternative to invasive blood pressure monitoring during laboratory studies.

Blood pressure measuring devices: recommendations of the European Society of Hypertension

There is a large market for blood pressure measuring devices not only in clinical medicine but also among the public where the demand for self measurement of blood pressure is growing rapidly. For consumers, whether medical or lay, accuracy should be of prime importance when selecting a device to measure blood pressure. However, most devices have not been evaluated for accuracy independently using the two most widely used protocols: the British Hypertension Society (BHS) protocol and the standard set by the US Association for the Advancement of Medical Instrumentation (AAMI). 1 2 The Working Group on Blood Pressure Monitoring of the European Society of Hypertension has decided to review blood pressure measuring devices regularly to guide purchasers.3 For this first report devices for which there is published evidence of independent validation using these protocols have been surveyed. Because most blood pressure devices have not been independently validated, only a fraction of the many devices available have been surveyed. Devices that have been validated recently for which results have not yet been published were not included, but this shortcoming should be addressed in future. #### Summary points Two manual sphygmomanometers have been validated, one is recommended Five devices for clinical use in hospitals have been validated, two are recommended 23 devices for self measurement of blood pressure have been validated, five are recommended 24 devices for ambulatory measurement of blood pressure have been validated, 16 are recommended Validations and recommendations will be updated on the BMJ s website ### Validation standards In 1987, the American Association for the Advancement of Medical Instrumentation published a standard for sphygmomanometers which included a protocol for evaluating the accuracy of devices.4 In 1990 a protocol was devised by the British Hypertension Society.5 Both protocols have since been revised. 1 2 Since the two protocols can be reconciled the …

European Society of Hypertension Position Paper on Ambulatory Blood Pressure Monitoring

Ambulatory blood pressure monitoring (ABPM) is being used increasingly in both clinical practice and hypertension research. Although there are many guidelines that emphasize the indications for ABPM, there is no comprehensive guideline dealing with all aspects of the technique. It was agreed at a consensus meeting on ABPM in Milan in 2011 that the 34 attendees should prepare a comprehensive position paper on the scientific evidence for ABPM.This position paper considers the historical background, the advantages and limitations of ABPM, the threshold levels for practice, and the cost-effectiveness of the technique. It examines the need for selecting an appropriate device, the accuracy of devices, the additional information and indices that ABPM devices may provide, and the software requirements.At a practical level, the paper details the requirements for using ABPM in clinical practice, editing considerations, the number of measurements required, and the circumstances, such as obesity and arrhythmias, when particular care needs to be taken when using ABPM.The clinical indications for ABPM, among which white-coat phenomena, masked hypertension, and nocturnal hypertension appear to be prominent, are outlined in detail along with special considerations that apply in certain clinical circumstances, such as childhood, the elderly and pregnancy, and in cardiovascular illness, examples being stroke and chronic renal disease, and the place of home measurement of blood pressure in relation to ABPM is appraised.The role of ABPM in research circumstances, such as pharmacological trials and in the prediction of outcome in epidemiological studies is examined and finally the implementation of ABPM in practice is considered in relation to the issue of reimbursement in different countries, the provision of the technique by primary care practices, hospital clinics and pharmacies, and the growing role of registries of ABPM in many countries.

European Society of Hypertension guidelines for blood pressure monitoring at home: a summary report of the Second International Consensus Conference on Home Blood Pressure Monitoring.

This document summarizes the available evidence and provides recommendations on the use of home blood pressure monitoring in clinical practice and in research. It updates the previous recommendations on the same topic issued in year 2000. The main topics addressed include the methodology of home blood pressure monitoring, its diagnostic and therapeutic thresholds, its clinical applications in hypertension, with specific reference to special populations, and its applications in research. The final section deals with the problems related to the implementation of these recommendations in clinical practice.

EFFECTS OF BLOOD-PRESSURE MEASUREMENT BY THE DOCTOR ON PATIENT'S BLOOD PRESSURE AND HEART RATE

Changes in blood pressure in 10 or 15 min periods during which a doctor repeatedly measured blood pressure by the cuff method were monitored by a continuous intra-arterial recorder. In almost all the 48 normotensive and hypertensive subjects tested the doctors arrival at the bedside induced immediate rises in systolic and diastolic blood pressures peaking within 1 to 4 min (mean 26.7 +/- 2.3 mm Hg and 14.9 +/- 1.6 mm Hg above pre-visit values). There were large differences between individuals in the peak response (range, 4--75 mm Hg systolic and 1--36 mm Hg diastolic) unrelated to age, sex, baseline blood pressure, or blood-pressure variability. There was concomitant tachycardia (average peak response 15.9 +/- 1.5 beats/min, range 4--45 beats/min) which was only slightly correlated with the blood-pressure rise. After the peak response blood pressure declined and at the end of the visit was only slightly above the pre-visit level. A second visit by the same doctor did not change the average size of the early pressor response or the slope of its subsequent decline.

Working Group on Blood Pressure Monitoring of the European Society of Hypertension International Protocol for validation of blood pressure measuring devices in adults

Working Group on Blood Pressure Monitoring of the European Society of Hypertension International Protocol for validation of blood pressure measuring devices in adults Eoin O’Brien,Thomas Pickering, Roland Asmar, Martin Myers, Gianfranco Parati, Jan Staessen, Thomas Mengden, Yutaka Imai, Bernard Waeber and Paolo Palatini and with the statistical assistance of Neil Atkins and William Gerin, on behalf of the Working Group on Blood Pressure Monitoring of the European Society of Hypertension

Prognostic value of 24-hour blood pressure variability

Objectives: Evaluation of the prognostic value of 24-h blood pressure averages and 24-h blood pressure variability. Design: After an initial thorough clinical and laboratory evaluation which included 24-h continuous ambulatory blood pressure monitoring, a group of hypertensive patients were re-examined after an average of 7.4 years. End-organ damage at the follow-up visit was related to different measures of blood pressure levels and variability obtained at the initial or the follow-up visit or both. Methods: Seventy-three patients with essential hypertension of variable severity, in whom ambulatory blood pressure was monitored intra-arterially for 24 h (Oxford technique) were re-examined at a follow-up visit (including echocardiographic assessment of left ventricular mass index) 4-13 years later (mean 7.4 years). The severity of end-organ damage was quantified by a score and related to clinic blood pressure at follow-up and to (1) clinic blood pressure, (2) 24-h blood pressure mean, (3) 24-h short-term and long-term blood pressure variability, and (4) end-organ damage, all assessed at the initial visit (multiple regression analysis). Results: The set of independent variables considered was significantly related to end-organ damage at follow-up (R = 0.51). The individual variables most important in determining end-organ damage at follow-up were clinic blood pressure at the follow-up visit (P < 0.01), the initial level of end-organ damage (P < 0.05) and long-term blood pressure variability (among half-hour standard deviation of 24-h mean blood pressure) at the initial evaluation (P < 0.05). The prognostic individual weight of the other haemodynamic parameters considered was less and not statistically significant. Conclusions: The results confirm that the level of blood pressure achieved by treatment and the degree of end-organ damage at the time of initial evaluation are important determinants of future end-organ damage related to hypertension. They also constitute the first longitudinal evidence that the cardiovascular complications of hypertension may depend on the degree of 24-h blood pressure variability.

Evaluation of the baroreceptor-heart rate reflex by 24-hour intra-arterial blood pressure monitoring in humans.

The baroreceptor control of the sinus node was evaluated in 10 normotensive and 10 age-matched essential hypertensive subjects in whom ambulatory blood pressure was recorded intraarterially for 24 hours and scanned by a computer to identify the sequences of three or more consecutive beats hi which systolic blood pressure (SBP) and pulse interval (PI) progressively rose (+ PI/ + SBP) or fell (− PI/ −SBP) in a linear fashion, according to a method validated in cats. In normotensive subjects, several hundred +PI/+SBP and −PI/−SBP sequences of 3 beats were found whereas the number of sequences of 4,5, and more than 5 beats showed a progressive drastic reduction. The mean slopes of plus; PI/ + SBP (7.6 ± 2.0 msec/mm Hg) and − PI/− SBP (6.4 ± 1.5 msec/mm Hg) sequences were similar, but in both instances there was a large scattering of the values around the mean (variation coefficients: 64.2 ± 4.7 and 62.6 ± 2.4%). The slopes decreased as a function of the sequence length and baseline heart rate and increased to a marked extent during the night as compared with daytime values. All sequences were more rare (−33.2% for +PI/ + SBP and −31.7% for −PI/−SBP) and less steep in hypertensive subjects (−40.3 and −36.2%, respectively), who failed to show the marked nighttime increase in slope observed in normotensive subjects. To our knowledge, these observations provide the first description in humans of the baroreceptor-heart rate reflex in daily life. This reflex is characterized by marked within-subject variations hi sensitivity due in part to hemodynamic, temporal, and behavioral factors. All features of the baroreceptor-heart rate reflex are unpaired hi essential hypertension.

European Society of Hypertension International Protocol revision 2010 for the validation of blood pressure measuring devices in adults.

The Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Ireland, dabl Ltd., Blackrock Co., Dublin, Ireland, Hypertension Center, Third University Department of Medicine, Sotiria Hospital, Athens, Greece, Istituto Scientifico Ospedale San Luca, IRCCS, Instituto Auxologico Italiano, Milan, Italy, Societe Francaise d’Hypertension Arterielle, Filiale de la Societe Francaise de Cardiolgie, Paris, France, The Department of Clinical Pharmacology and Therapeutics, Tohoku University Graduate School of Pharmaceutical Science and Medicine, Sendai, Japan, Centre for Epidemiological Studies and Clinical Trials, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China, University Clinic Bonn, Department of Internal Medicine, Bonn, Germany and Guy’s and St Thomas’ Hospitals, London, UK