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Objective: The objective of this study was to describe and analyse the nycthemeral variations in blood pressure (BP) by ambulatory BP monitoring (ABPM) over 24 h in patients with heart failure (HF)., Methods: The study population included 50 stable HF patients hospitalized in a cardiology department for acute pulmonary oedema. Parameters studied were: New York Heart Association class, clinical resting BP and heart rate in sitting and then standing positions, ABPM parameters, distance covered during a 6-min walking test, echographic left ventricular ejection fraction (LVEF), natremia, kaliemia, creatininemia, plasma haemoglobin and N-terminal fragment of brain-type natriuretic peptide levels., Results: Clinical hypertension was noted in 20% of patients (10/50) and orthostatic hypotension in 16% (8/50). Nine of 50 patients (18%) were hypertensive during the day and 21 (42%) at night. Thirty-nine of the 50 patients (78%) are nondippers. Nondipper patients are more prevalent when the HF has been present for more than 24 months (95 vs. 67%, P=0.04). This prevalence does not differ depending on New York Heart Association class or LVEF. Furthermore, there exists: (i) a significant positive relationship (R=0.46, P=0.02) between the diastolic BP (DBP) over 24 h and the distance covered during the walking test; (ii) a significant negative relationship between the day-night differences (in mmHg) of the systolic BP (SBP) (R=-0.46, P=0.01) and DBP (R=-0.33, P=0.03) and the duration of HF, between the day-night difference of the DBP and the LVEF (R=-0.34, P=0.02) and (iii) between the day-night differences of the SBP (R=-0.48, P=0.001) and the DBP (R=-0.32, P=0.03) and natremia. The day-night difference of the SBP has a positive correlation with plasma haemoglobin level (R=0.32, P=0.03)., Conclusion: This study confirms the feasibility of carrying out ABPM with an adapted device in HF patients with atrial fibrillation. ABPM allows diagnosis to be more precise than the clinical measuring of BP abnormalities, which have a pejorative prognosis (e.g. hypertension, hypotension, nondipper status).

Background: In newly diagnosed apnoeic patients without a history of hypertension, clinical hypertension is underdiagnosed in at least 40% of the cases. An increase in diastolic blood pressure is the most frequent pattern encountered., Objective: To assess clinic and 24-h blood pressure, baroreflex sensitivity and left ventricular mass for identifying the prevalence, the type and the consequences of hypertension in newly diagnosed apnoeic patients., Patients and Methods: Fifty-nine unselected patients (age = 48 +/- 12 years, body mass index = 28.1 +/- 4.5 kg/m2) referred to a university hospital sleep laboratory for symptoms suggesting obstructive sleep apnoea were included. Diagnosis of apnoea was accepted when respiratory disturbance index was > or = 15/h of sleep. Blood pressure was considered as normal by their general practitioner and all of them were free of any medication for hypertension. Echocardiography, 24-hour ambulatory blood pressure monitoring and assessment of the baroreflex sensitivity were performed., Results: Forty-two percent of the apnoeic patients demonstrated a clinical hypertension, 34 subjects (58%) had a daytime hypertension, and 45 patients (76%) had a night-time hypertension, using 24-h monitoring. All the daytime hypertensives also had night-time hypertension. Forty-seven of the 59 patients (80%) were hypertensive either in the clinic or using 24-h recording. Diastolic and systolo-diastolic hypertension were the prominent types of hypertension observed both by clinic or ambulatory measurements. Respiratory disturbance index was significantly higher in apnoeic patients suffering isolated diastolic hypertension than in the normotensives (50.9 +/- 26.5/h versus 36.0 +/- 12.3/h, respectively; P = 0.02). The prevalence rate of left ventricular hypertrophy was high (between 15 and 20%) and occurred independently of associated hypertension. Baroreflex sensitivity was altered whatever the type of hypertension and decreased with the severity of obstructive sleep apnoea., Conclusion: Hypertension is hugely underdiagnosed in apnoeic patients unknown to be hypertensive. Use of 24-h blood pressure monitoring allowed the diagnosis of twice as much hypertension than did clinical measurement. Even at the beginning of their history of hypertension, apnoeic patients exhibited chronic adaptations of their cardiovascular system, as shown by early changes in baroreflex sensitivity and an increased prevalence of left ventricular hypertrophy.

Background: Circadian blood pressure (BP) measurements provide more information on hypertensive complications than office BP measurements. The purpose of this study was to analyze the efficacy of the first-line combination of perindopril 2 mg plus indapamide 0.625 mg versus atenolol 50 mg on BP parameters and variability over 24 h in patients with hypertension., Methods: A double-blind, randomized, controlled, 12-month study comparing perindopril/indapamide and atenolol was performed in 201 patients (age 55.0 years) with uncomplicated sustained essential hypertension. Ambulatory BP measurements (ABPM) were done every 15 min over 24 h., Results: After 1 year of treatment, the decrease in systolic BP was significantly greater for perindopril/indapamide than for atenolol during the entire 24-h period (-13.8 v -9.2 mm Hg), the daytime and the nighttime periods (P <.01). Diastolic blood pressure (DBP) variations were comparable for the two groups (-7.2 v -8.3 mm Hg, NS). Pulse pressure (PP) reduction was also significantly greater for perindopril/indapamide than for atenolol (for the whole 24 h, -6.6 v -0.9 mm Hg, P <.001). The through to peak (T/P) BP ratio and the smoothness index were comparable in the two groups for DBP. For systolic blood pressure (SBP), higher values of the T/P ratio (0.80 v 0.59) and the smoothness index (1.45 v 0.98; P <.02) were achieved for the perindopril/indapamide combination than for atenolol., Conclusions: The perindopril/indapamide first-line combination decreased SBP and PP more effectively than atenolol. Moreover, the BP control effect was smooth and consistent throughout the 24-h dosing interval and BP reduction variability was lower than the one induced by atenolol.

Objectives: To compare the autonomic nervous system activity indexes obtained from photoplethysmography in dipper and non-dipper hypertensive patients and to seek a potential influence of sex on the relation between autonomic nervous system and the nocturnal decrease in blood pressure., Methods: We studied 245 hypertensive patients, who underwent 24 h ambulatory blood pressure monitoring (ABPM), photoplethysmographic blood pressure recording, and echocardiography. Non-dipping patients were defined as those whose nocturnal decrease in systolic blood pressure (SBP), diastolic blood pressure (DBP), or both was less than 10% of the daytime blood pressure. Spectral powers of SBP, DBP and heart rate were obtained from photoplethysmographic recordings over three main frequency bands: very low frequency (0.005-0.05 Hz), low frequency (0.05-0.14 Hz) and high frequency (0.14-0.40 Hz)., Results: Because their ABPM were normal (less than 135/85 mmHg; n = 33), of poor quality (n = 22) or performed at a period too far from the photoplethysmographic recording (n = 17), 66 patients were excluded from the analysis. The remaining 179 patients comprised 117 dippers and 62 non-dippers. The groups did not differ regarding clinical and echocardiographic characteristics, irrespective of sex. Low-frequency spectral powers were significantly lower in non-dippers than in dippers, whatever the signal, whereas high-frequency spectral powers did not differ significantly between the groups. The nocturnal decrease in blood pressure increased with increasing low-frequency spectral powers, but was negatively correlated with high-frequency spectral powers. Multivariate linear regression analysis identified low-frequency spectral power of SBP and clinic DBP as independent factors determining the decrease in blood pressure. After adjustment for all significant covariates, the odds of being a non-dipper did not differ between men and women., Conclusion: A non-dipper profile seemed to be associated, in both men and women, with lower low-frequency spectral powers compared with those in dippers, suggesting impaired sympathetic arterial modulation.

Objective: To study the relationships between evolution of changes in blood pressure (BP) over the 24 hour cycle and their cardiac and vascular consequences in mild to moderate hypertensive (HT) subjects (WHO criteria)., Material and Methods: 151 patients presenting with mild to moderate essential HT (Age 49 +/- 12 yrs, 63 M 44W)--ambulatory measurement of BP over 24 hours (Spacelabs 90207) automatic determination of the diurnal cycle by Fourier analysis (5 harmonics) and calculation of the slope of BP variation (mmHg/hr) at the point of transition from day to night (nocturnal dip slope (NDS)), and at the change from night to day (morning rise slope (MRS). Patients with inversion of the day-night cycle were excluded, day-night being arbitrarily defined as 7 to 22 h and 22 to 7 h. Echography of left ventricular mass index (LVMI)/Penn convention, formula of Devereux, and carotido-femoral distensibility by pulse wave velocity (PWV, Complior Colson France)., Results: Ambulatory measures of BP and HR and of cardiovascular parameters were as follows. [table: see text] The slope of nocturnal fall (NDS) and morning rise in SBP (MRS) is significantly correlated with LVMI (NDP r = -0.02, p = 0.049, MPP r = 0.21, p = 0.029) and with PWV (MPP: r = 0.32, p = 0.005). No relationship was found with the DBP values. By multivariate analysis taking into account age, sex, 24 h SBP, MPP slope velocity was the only variable which was significantly related with the model of PWV and LVMI (p < 0.001)., Conclusion: Dipper and non-dipper studies have been performed to examine the consequences of day night variations in BP. The evolution of diurnal changes in BP seems to have an effect on the vessels and heart and may be a simple analysis tool for assessing prognosis and therapeutic effects.

Objectives: 1) To compare the autonomic nervous system activity parameters obtained from a photoplethysmographic recording in dipper and non dipper hypertensive. 2) To look for an interaction between dipper/non dipper status and gender., Methods: Prospective study involving 245 untreated hypertensives (51 +/- 13 years, 146 men, 99 women). All of the patients underwent a 24-hour ambulatory blood pressure measurement (ABPM) as well as an echocardiography for left ventricular mass index determination (LVMI) and a photoplethysmographic recording of blood pressure (BP). Nondippers were defined as those whose nocturnal decrease in systolic BP (SBP) and/or diastolic BP (DBP) was < 10% of daytime BP. Spectral powers were obtained from the photoplethysmographic recording using a fast Fourier transform over the low frequency band (LF) and the high frequency band (HF). Baroreflex sensitivity (BRS) was evaluated by the sequences method., Results: Of the 245 patients, 159 were dippers (98 men, 61 women) and 86 were non dippers (48 men and 38 women). Clinic BP was significantly higher in non dippers than in dippers (168/101 vs 161/98 mmHg; p < 0.01 for SBP and p < 0.05 for DBP) whereas daytime ABPM and LVMI were not different, whatever the gender. LF spectral powers were significantly lower in non dippers than in dippers for SBP (respectively 25 +/- 11% vs 30 +/- 13%; p < 0.01) for DBP (respectively 35 +/- 14% vs 41 +/- 15%; p < 0.01) and for HR (respectively 34 +/- 15% vs 38 +/- 15%; p = 0.03). They showed a positive correlation with the nocturnal SBP fall (r = 0.21, p < 0.001 for SBP and DBP spectral powers, r = 0.19; p < 0.005 for HR spectral power) and with the nocturnal DBP fall, too (r = 0.19; p < 0.005 for SBP spectral power, r = 0.20; p < 0.002 for DBP spectral power, r = 0.19; p < 0.005 for HR spectral power). HF spectral powers tended to be higher in non dippers than in dippers but in a non significative way. BRS was roughly the same in dippers and non dippers (7.5 +/- 2.7 vs 7.0 +/- 3.1 ms/mmHg, NS). The interaction between non dipper/dipper status and sex was non significant whatever the LF spectral power., Conclusions: 1) The greater the nocturnal BP fall, the higher the sympathetic activity indexes. 2) This relationship was found both in males and females.

Objective: To determine how much of the variations of blood pressure during a 24 hour period could be accounted for by a change in activity using an accelerometer to detect the physical activity and establish a predictive model., Materials and Methods: 18 healthy subjects (mean age 25 +/- 2 yrs) were studied during daily life (24 hours) twice one week apart. The systolic and diastolic blood pressure, heart rate (HR), and time of measure were recorded by ambulatory monitoring using Spacelabs (4 measures per hour). A portable digital memory device was designed for the 24 hours ambulatory monitoring of HR (ECG) and physical activity. This device consists of an ECG Holter (ELA medical model Cinesis with digital memory) and a three piezoresistive type accelerometer sensors (prototype ELA research) able to record physical activity in the 3 space dimension., Results: The data of the first recording were compared to the predicated values from the application of a logarithmic model of activity to the second recording. The model then predicted 53 +/- 19% of the systolic BP values of the test day. The mean individual difference for a given time period of one hour between the measured and the predicted systolic BP from the model was 1.45 +/- 3.1 mmHg with a range of [-6.9; 3.4 mmHg]. The mean individual systolic BP difference for the same given time period of one hour but without predictive model was 1.29 +/- 10 mmHg with a range of [-28; 43 mmHg]., Conclusion: This study show that 3 D accelerometer is an easy tool to program individual model of ambulatory blood pressure variability. The introduction of this qualitative method seems logical in therapeutic trial.

The blood pressure shows circadian variation in normal subjects with higher diurnal than nocturnal values: the difference between day and night time blood pressure is about 10-20 mmHg for systolic and for diastolic blood pressure. These variations are mainly related to physical and/or psychosensorial stress: the physician is himself a cause of increased blood pressure (the "white coat" effect). The degree of the nocturnal decrease in blood pressure which is maximal 2 and 3 o'clock is related to the quality and depth of sleep. The nocturnal decrease is followed by an increase in blood pressure when the person wakes up (early morning peak). Diagnostic signs: a physiological inversion of the circadian rhythm may be observed in people who sleep during the daytime and work at night. There would seem to be less of a nocturnal fall in black persons in the United States. Some pathological conditions can inverse or at least disturb the ciacadian variation: apart from hypertension, this has been reported in autonomic nervous system disease, in diabetics with autonomic neuropathy in some elderly patients, in Cushing's syndrome, after cardiac transplantation, etc... In hypertensives, the lack of nocturnal decrease of the blood pressure or an inversion in circadian rhythm should be looked for in severe and secondary hypertension such as associated with pheochromocytoma, or in renal dialysis patients. In toxaemia of pregnancy, this abnormality may herald an eclamptic crisis. Prognostic signs: in normotensives (especially in black persons) and hypertensives, inversion of the circadian rhythm is associated with more severe left ventricular hypertrophy and a higher morbidity.

A number of studies have shown changes and even an inversion of the diurnal cycle in certain affections: Cushing's syndrome, pheochromocytoma, severe renal failure, autonomous nervous system disorders, pre eclampsia etc.... The authors studied diurnal and nocturnal variations of blood pressure in type I diabetics. Twenty-nine normotensive (WHO criteria) type I diabetics (NTD) average age 34.9 +/- 11 years, with diabetes of 13.6 +/- 8 years standing, and 118 normotensive non-diabetics (NT) aged 20 to 60 years (distributed by decennies according to age and sex) were studied. The systolic (SBP) and diastolic blood pressures (DBP) were recorded at rest in the decubitus position by the phase V indirect auscultatory method and during ambulatory monitoring (automatic Spacelabs no. degrees 90207 device) every 15 minutes during the daytime and 20 minutes during the night. The mean values were studied; the values of the heart rates were identical in the NTD and NT populations. Significant difference in SBP between the Nt and NTD were recorded: during daytime there was no difference either in SBP or DPB; during the night, there was a significant difference in SBP. A study of the day-night differences both in absolute and in relative values (day-night difference with respect to daytime values as a percentage) did not show any statistically significant differences between the two populations. Abnormalities of the 24 hour profile, defined as absence of a 5 mmHg fall in nocturnal BP values, were looked for but there were no differences between the NT and NTD subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Circadian blood pressure variations were studied in 110 normotensive (blood pressure less than or equal to 140/90 mmHg) and 142 untreated essential hypertensive (blood pressure greater than or equal to 160/95 mmHg) subjects. Measurements were carried out under full ambulatory conditions by the oscillometric method, using an automatic device (SpaceLabs 5200). Readings taken between 9.00 a.m. and 7.00 p.m. were defined as daytime values (activity), and those taken between 11.00 p.m. and 7.00 a.m. as night-time values (sleep). Blood pressure was significantly higher during the day than at night. The day-night differences were significantly higher in the hypertensive than in the normotensive subjects. There was a significant correlation for both systolic blood pressure (SBP) and diastolic blood pressure (DBP) between the day-night differences and DBP values at rest. The difference between the normotensives and hypertensives was smaller when the day-night difference was calculated as a percentage of the daytime blood pressure, but the SBP difference remained significantly higher in the hypertensives. The number of subjects without a nocturnal blood pressure decrease or with a decrease of less than 5-10 mmHg was not statistically different between the normotensives and the hypertensives. These results are a contribution towards an understanding of day-night blood pressure differences in hypertensive and in normotensive subjects. A knowledge of the 24-h blood pressure profile in the individual patient is important because abnormal profiles may be linked with various etiologies responsible for dysregulation, and might have prognostic implications.

Blood pressure and heart rate of 15 male shift workers were measured every 15 minutes for 24 hours during three work shifts: morning, 4:00 AM to noon; afternoon, noon to 8:00 PM; and night, 8:00 PM to 4:00 AM. For each shift, 24-hour systolic and diastolic blood pressure showed a large "trough" (the low pressure span) and a continuous range of elevated pressure (the high pressure span). Fourier series were used to model the 24-hour blood pressure profiles. A careful examination of the residuals (measured minus predicted pressures) showed that four harmonics were necessary to describe the data accurately. The model enabled localization in each blood pressure profile of the high and low pressure spans that did not coincide with the subject's work and rest periods. The time and slope of blood pressure entering and leaving these spans could also be individually determined. Mean blood pressure during the high pressure span was the same for the three shifts, but mean blood pressure during the low pressure span was lower when the subject worked in the afternoon. During that shift, the systolic blood pressure slopes entering and leaving the low pressure span were steeper than during the two other shifts. The high pressure span was longest during the night shift and shortest during the afternoon shift. Therefore, a change in the working time profoundly perturbed the 24-hour blood pressure profile.(ABSTRACT TRUNCATED AT 250 WORDS)