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F Tremel

Publications and source records attributed to F Tremel.

At least 19 recordsLinked to original sources
PubMed1996

Comparison of home and clinical blood pressure measurements: clinical applications.

While measurement of blood pressure in the doctor's office remains the method of reference of the WHO, self-measurement yields complementary information, namely: measures outside the surgery, good estimation of the level of blood pressure at home from several day's data, better reproducibility related to standardized conditions of measurement imposed by the constraints of immobility and manoeuvre of the machine. The modalities of variation of BP by automeasure are known: diminution in the BP by automeasure of about 2 to 4 mm Hg between the first and the third measure performed at 1-min intervals, no significant evolution over 3 days and BP more elevated in the evening than in the morning. In comparison with the WHO data, the BP is significantly lower. Recently reference values have been proposed, giving as the upper threshold of normotension = 127/ 83 mm Hg and hypertension = 147/ 86 mm Hg. As regards diagnosis SM allows the identification of "white coat hypertension", and thus avoids treating these patients. The indirect prognostic value via target organ effect is under evaluation, and may be at the same level as ambulatory blood pressure measurement (ABPM). Given the utilisation of validated automatic machines and a rigorous methodology SM is beginning to be used satisfactorily in clinical trials. Numerous studies are still necessary in order to clearly define the place of SM in comparison to WHO and AMBP in the management of hypertension.

Antihypertensive Agents↗
PubMed1996

[Diagnostic value of renal scintigraphy with MAG 3 and DTPA in the diagnosis of renal artery stenosis].

UNLABELLED: Angiography still remains the first line investigation to demonstrate a renal artery stenosis. We have evaluated the sensitivity and the specificity of renal scintigraphy in the diagnosis of renal artery stenosis using two technetium markers, MAG 3 and DTPA. PATIENTS: 45 hypertensive (HT) patients (WHO criteria) referred for investigation of renovascular hypertension according to the criteria of the AHA Scientific Council and were found to have a unilateral renal artery stenosis of varying severity. Age was 61 > +/- 13 years; sex-ratio F/M 21/24; creatinine < 150 mumol/l. There were non insulin dependent diabetics, and none had been treated with ACE inhibitors or diuretics for 15 days. Bilateral arterial stenosis was excluded a posteriori. METHODS: MAG3 and DTPA scintigraphy were performed one hour after a dose of 25 mg of captopril plus hydration with 500 ml of intravenous saline. Blood pressure was measured by dynamap every 15 min from minus one hour to the end of the study. The principle outcome measure was nephorgram phase and the secondary measure was the angiographic phase (two images per second). The two scintigraphy techniques were performed at a mean interval of 2.9 +/- 2.1 days. Digitized angiography via the arterial route was performed using left anterior oblique and right anterior oblique images. RESULTS: [table: see text] CONCLUSION: There was only one false positive scintigraphy result with a polar artery. In contrast 45% of unilateral stenoses were not diagnosed by scintigraphy. Both markers gave similar results even if subjectively the MAG3 images were of better quality. Analysis of the angiographic phase and of the size of the kidneys did not improve the diagnostic accuracy and could lead to false positive results.

Aged↗
PubMed1995

[Ambulatory measurement of blood pressure].

The advent of new techniques has greatly contributed to the development of ambulatory measurement as a noninvasive method for evaluating blood pressure. The technique implies use of a validated and reliable standardized apparatus. The operator must strictly comply with operating procedures, which must also be explained to the patient. Ambulatory measurement can be meaningful only if the results are compatible with reference values, which have now been established, and if the causes of possible error can be recognized and interpreted. Ambulatory blood pressure measurement has greatly improved our knowledge of physiological and pathological variations over the circadian cycle including day/night variability and the effects of psychosensorial stimulation. Diagnostic indications are clearly identified and include borderline hypertension suspected but not identified after about 3 months, the white coat effect, severe hypertension when modifications in the circadian cycle are suspected, paroxysmal hypertension, suspected pheochromocytoma, and gravid hypertension or an inversion of the circadian cycle possibly preceding an episode of eclampsia. There are also a certain number of particular indications in patients with degenerative or primary conditions affecting their autonomy. The true prognostic value of these recordings was recognized several years ago and has been confirmed by clinical trials. For example, the white blouse effect has no significant implication in terms or predicting less favourable morbidity or mortality. Finally, ambulatory blood pressure measurement has been definitively shown to be a valid method for evaluating the therapeutic effect of an anti-hypertensive drug in a given patient, especially when resting levels are questioned. For therapeutic trials, ambulatory measurements serve as a reference to evaluate the effect of treatment on the circadian cycle. Peak/dip levels can thus be determined in comparison with the residual effect of the drug. A large number of studies remain to done to identify the full potential of this method.

Blood Pressure↗
PubMed1995

Diagnostic and prognostic value of exercise testing.

Measuring blood pressure during exercise under a standard protocol could be a useful diagnostic method in high-risk patients and in borderline hypertensive subjects. It may also serve as an adapted test for hypertensive subjects undergoing physical activity at work or at leisure time with a particular cardiovascular work load. It can be used as a method of assessment to confirm the efficacy of an antihypertensive drug, and for prognostic evaluation of cardiovascular risk in terms of morbidity and mortality. An exercise blood pressure profile does not provide information about blood pressure during activities of daily living. For this purpose, ambulatory blood pressure measurement appears to be more relevant.

Blood Pressure↗
PubMed1995

Examination of variability in arterial blood pressure at rest using spectral analysis in hypertensive patients.

INTRODUCTION: We hypothesize that in essential hypertension sympathetic nervous activity is related to the development of left ventricular hypertrophy, which can be regarded as a measure of the severity of hypertension. METHODS: Using spectral analysis, we studied the short-term variability in resting blood pressure and heart rate in essential hypertensive subjects. We measured blood over 10 min using a Finapres in 88 subjects after 20 min rest. We performed echocardiography to evaluate left ventricular hypertrophy and thereby identified three groups: 23 control subjects (group I), 29 hypertensive subjects (World Health Organization criteria) without left ventricular hypertrophy (group II) and 36 hypertensive subjects with left ventricular hypertrophy (group III). None had been treated for hypertension before the study. RESULTS: The variability in blood pressure over a low-frequency period considered to be a marker of sympathetic activity was significantly increased in group II compared with groups I and III (analysis of covariance taking into account blood pressure and age). The variability in heart rate was similar in groups II and III, but both groups had a significantly reduced variability in heart rate compared with group I. CONCLUSION: These data, which examine globally, using a non-invasive method, all neurohormonal factors associated with the development of left ventricular hypertrophy, demonstrate that, in the time course of hypertension, low-frequency oscillations in blood pressure and heart rate are shifted to a lower level, presumably reflecting altered function of the sympathetic nervous system. We suggest that spectral analysis of blood pressure at rest in hypertensive patients can lead to complementary information to single measures of blood pressure and detect differences in the cardiovascular regulatory system.

Age Distribution↗
PubMed1995

[Reproducibility of echocardiographic parameters by automatic detection of contours in hypertensive patients].

The reproducibility of automatic outline detection is a echocardiographic reproducibility which has been poorly evaluated in patients with cardiomyopathy. Two independent observers identified the systolic surface and mid and end diastolic surfaces of 27 hypertensive patients, who had been referred to the laboratory for the measurement of left ventricular mass. Each observer examined on two occasions all parameters and all parameters were measured at least 2 hours apart. The coefficient of variation (CV) expresses the reproducibility of each measurement. The intra observer was 10 to 15% and the inter observer 15 to 22% for the measurement of surface area. The coefficient of variation is regularly greater than 20% for measures of maximum speed, which characterise surface changes in diastole. The automatic detection of contours is a echocardiographic tool whose potential is great for evaluating left ventricular function but the current versions can only be applied to very selective group of patients depending on the quality of their echographic window for acoustic quantitation. This technique is very operator dependent, in particular as regards setting the gains and this explains its poor reproducibility and its limited interest in daily clinical practice.

Adult↗
PubMed1995

[Paradoxic changes in the morphology of blood pressure wave in hypertensive heart diseases].

UNLABELLED: The objective is to study the relation between left ventricular (LV) effect (index of LV mass (LVMI) and index of inotropic state) and arterial compliance determined but the proximal aortic pressure waveform and by the carotid femoral pulse wave velocity. MATERIAL: 72 untreated hypertensives; systolic blood pressure (SBP) 170 +/- 18 mmHg/diastolic blood pressure (DBP); heart rate: 69 +/- 9 batt/min; age: 48 +/- 13 years; duration of hypertension 4.6 +/- 4.8 years; sex ratio 49 M/23 F. OBJECTIVE: Proximal aortic pressure waveform (carotid artery) was studied by applanation tonometry. We derived the index of amplification (AI = Pmax-Pinflex)/PP, %), pulse pressure (PP), the maximum rate of rise of pressure (dpdt, mmHg.s-1). Echocardiography was used to define the index of LV mass (VLMI), end systolic volume (ESV), end systolic stress (ESS), myocardial contractile force (ESS/ESV), inotropic state (SBP/ESV). Carotid-femoral pulse wave velocity was determined by mechanogram (PWW m/s). RESULTS: 1. Relationship of physiological changes of AI and SDA to age, height, PP, DBP, PWV, and LVMI were observed in table I (r-Pearson cor. coefficient, * < p 0.05; **: p < 0.001). [table: see text] In stepwise regression analysis, even allowing for BP, age, and height, there was no relationship between LVMI and the index of aortic amplification (AI). 2. In the subjects with LVH (LVMI > 110 g/m2) we found a bimodal distribution of the AI which defines two groups in agreement with the Murgo Classification. [table: see text] In type B, where AI is weaker, the indices of aortic rigidity are reduced, there is an increased ESS and a paradoxal fall in LV performances. CONCLUSION: Analysis of proximal aortic pressure waveform don't allow to predict index of LV mass. These results suggest that in the sphere of LV aortic compiling the reduction of LV function contributes to modification of the BP waveform with diminution of dpdt and the index of amplification.

Adult↗
PubMed1995

[Baroreflex sensitivity and vascular involvement in hypertension].

UNLABELLED: Relationships between baroreflex sensitivity (BRS) and arterial distensibility are evaluated by continuous measurement of blood pressure (Finapres) and carotid-femoral pulse wave velocity measurement (PWV); 73 subjects are recruited on WHO criteria (age: 48 +/- 13). An ambulatory measurement of BP is also performed to evaluate the mean BP 24 level. The BRS is evaluated at rest during 20 min of acquisition data in a lying position, using a dedicated software [(automatic detection by of BP sequences were 3 or more systolic BP and RR interval increased of 1 mmHg for SBP and 4 ms for RR (PS+/RR+) or decreased (PS-/RR-)]. The BRS is the slope of the regression line between SBP and RR interval of each sequences (if correlation coefficient > 0.95). RESULTS: resting BP: SBP/DBP = 170 +/- 12 mmHg. HR 72 +/- 15 batt/min, PWV = 10.8 +/- 3.2 m/s. Mean BRS is 8.2 +/- 3.8 for PS+/RR+ and 8.7 +/- 3.8 ms/mmHg PS-/RR-. The coefficient of correlation (Pearson) between PWV and BRS is -0.59* for PS+/RR+ and -0.41* for PS-/RR- (*: p < 0.01). In multivariate analyses, these relations were statistically independent of age and BP for the sequences PS+/RR+ but not for the sequences PS-/RR- suggesting a predominant vagal alteration in hypertensive subjects associated with the alteration of carotido-femoral pulse wave velocity.

Arteries↗
PubMed1995

Second-generation calcium antagonists and ambulatory blood pressure monitoring.

Ambulatory blood pressure monitoring (ABPM) is a particularly useful method for evaluating the effects of antihypertensive drugs. ABPM allows the therapeutic effect of an agent to be assessed continually by a large number of measurements, and the greater number of readings contributes to the higher degree of reproducibility associated with ABPM compared to other methods for measuring blood pressure. ABPM also enable measurements to be taken in "real-life" situations and removes the problem of observer bias. The number of patients required for clinical studies can be significantly reduced by using ABPM. It is still essential, however, to identify "white coat" subjects, placebo responders, and patients who do not respond to the treatment. ABPM studies have demonstrated that the novel dihydropyridine calcium antagonist, lacidipine, significantly reduces both systolic and diastolic blood pressures over a 24-h period, both during the day and at night. Furthermore, although the trough-to-peak ratios of many calcium antagonists have been shown to fall below the recommended level of 50%, lacidipine has a ratio above 60%. Other ABPM studies have also shown that lacidipine can correct the 'early morning increase' in blood pressure without effecting the 24-h nycthemeral profile.

Blood Pressure↗
PubMed1994

[Left ventricular hypertrophy and blood pressure variability during rest and ambulatory monitoring in the hypertensive patient].

To study the relationship between assessment of blood pressure (BP) variability measured by continuous measurement (Finapres) or discontinuous ambulatory (ABPM Spacelabs) in 70 untreated essential hypertensive subjects (mean age 51 +/- 12) and their relationship with the development of left ventricular hypertrophy (LVH). There is no relationship between the BP variability measurements either by Finapres nor by ABPM. Multiple regression analysis show that ambulatory systolic BP variability (standard deviation) and resting BP variability (spectral analysis of SBP in the medium frequency band 0.1 Hz) are related to LVH index when we take into account age and BP difference (to explain LVH) (p < 0.001) ABPM SBP variability increase with LVH, while resting SBP measurement of BP variability (Mayer waves) significantly decreased. The study points to the different role of BP variability measurements in the mechanisms related to left ventricular hypertrophy and to the interest of continuous BP resting spectral analysis measurements.

Blood Pressure↗
PubMed1994

[Blood pressure variability during rest and left ventricular hypertrophy in the hypertensive patients. A spectrum analytic approach].

OBJECTIVE: To study the relationship between spectral analysis measurement of blood pressure (BP) and heart rate (HR) at rest, in untreated essential hypertension, and their relationship with the development of left ventricular hypertrophy (LVH). DESIGN AND METHODS: 41 untreated hypertensives (25M/16W, age 50 +/- 12, range 23-73) were measured at rest (WHO criteria DBP > 90 mmHg) by digital continuous photoplethysmography (Finapres 2300 (F), 6 mn of measurement in the dorsal decubitus position and standing up). Measurement of LVH (Devereux criteria, left ventricular mass index LVMI, g/m2) to analyse two groups (LVMI+: LVMI > 107 if women and 120 if men; n = 19; LVMI = 137 +/- 25), and (LVMI-; n = 22; LVMI = 92 +/- 17). The overall variability is standard deviation (SD), spectral analysis variability (SA) is FFT of 256 points over 3 periods low (LF: 0.004-0.07Hz), medium (MF: 0.07-0.13Hz), high (HF: 0.13-0.5Hz). Comparisons by Wilcoxon test and Anova (age, sex) (* p < 0.05, ** p < 0.01). RESULTS: By WHO criteria, the SBP was significantly lower in the LVMI-group (153 +/- 10 vs 165 +/- 18**), the DBP was not significantly different (94 +/- 6 vs 96 +/- 10). By continuous measure (F) at rest there was no significant difference for SBP or DBP. On standing up the SBP was significantly lower in the LVMI-group (148 +/- 20 vs 162 +/- 22**). The SD of the DBP at rest was more elevated in the LVMI-group (3.34 vs 3.06*), but not significantly different standing up. There was no significant difference in SBP at rest (6.7 vs 6.32) or standing (9.13 vs 11.5). The Spectral analysis of the MF was significantly elevated in the LVMI-group at rest for SBP (3.56 vs 3.01*), DBP (1.99 vs 1.19*), and HR (1.79 vs 1.77*). This was not significantly different in the LF and HF for SBP, DBP, HR. CONCLUSION: These results are different from those obtained by invasive ambulatory measures. The spontaneous variability in BP and HR at rest is increased when there is no cardiac effect (LVMI-). SA gives additional information in showing that the increase in variability is due to an increase in the Mayer waves, suggesting the existence of an elevation in adrenergic tone in hypertensive patients not having LVH.

Adult↗
PubMed1994

[Changes in the morphology of the Doppler wave of the pulmonary venous blood flow in hypertensive heart diseases].

Analysis of pulmonary venous flow can contribute to understanding of ventricular diastole; 40 essential hypertensive subjects (HT) who had never been treated and 30 healthy normotensive subjects (NT) were studied by Doppler-echocardiography. All the subjects had normal systolic function on echocardiography. The analysis focussed on the velocity of transmitral flow as measured by pulsed Doppler, measuring E and A waves, and also on flow in the right superior pulmonary vein: S and D waves measured in the apical position. The D wave appeared to correlate with age (r = 0.62, p < 0.001), with systolic blood pressure (SBP) (r = -0.44, p < 0.05) a correlation which remained after adjustment for age, and for measures of diastolic function across the mitral valve: A wave, and to E wave in a less closely related fashion. The D wave was of a lower velocity with mitral Doppler type A than with normal mitral Doppler (46 +/- 9 vs 36 +/- 8 cm/s; p < 0.005). The S wave was weakly related to morphological measurements of LV such as end-diastolic diameter of LV(r = 0.3; p < 0.01). The Doppler of pulmonary venous flow may help in describing impairment in LV filling by giving complementary data on Doppler mitral flow. A type 1 mitral Doppler corresponds to a low amplitude D wave with the presence of elevation of LVEDP which limits LV filling. In difficult situations when E and A velocities are similar (normal or pseudonormal form) a weak velocity of D wave is in favour of type 1.

Adult↗
PubMed1993

[Delayed potentials and left ventricular hypertrophy].

Delayed potentials (DP) (ECGHA) are markers of the occurrence of ventricular rhythm disturbances, and have a prognostic value after myocardial infarction. In hypertensive heart disease, the prevalence of DP is variable according to the literature (1-40%) and their prognostic significance is not known. We examine the frequency of DP in hypertension (HT) and the relationship between DP and left ventricular hypertrophy (LVH) as defined by echocardiographic estimation of the LV mass index (LVMI). We investigated 50 consecutive patients with essential HT who were being assessed as regards cause and effects of HT. Exclusion criteria were coronary artery disease, bundle branch block and poor echocardiographic trace. ECGHA was registered by means of ART device. The presence of DP as defined according to the criteria of Kacet. LV mass was determine according to the method of Penn and LVH defined according to the criteria of Devereux. Besides LVMI, were examined age, sex, duration of HT, micro-albuminuria, LVH on ECG (Sokolow index and strain-ECG). There were no correlations between the different variables studied and the presence of DP. The results relating to LVMI are shown in Table. There were no correlation between DP and LVH on echography. Other explanations, electrophysiologic, ischemic and histological may explain the greater incidence of BP observed in hypertensive heart disease. [table: see text] The prevalence of DP was not significantly different as regard the presence or absence of LVH (35% vs 25%; p = 0.53). In the 10 patients with the highest LVMI, the DP were enregistered 3 times.

Action Potentials↗
PubMed1993

[Segmental arterial compliance of the radial artery: physiological role of age, hypertension and type I insulin-dependent-diabetes].

OBJECTIVE: To study the structural modifications of a muscular and medium-size radial artery as regards age, in normal subjects (NT) and HT and DTI. MATERIAL AND METHODS: Transverse study with 39 NT aged 48 +/- 16 years, were compared to 22 HT, aged 50 +/- 11 years, and to 22 DT aged 37 +/- 12 years. An echo-tracking system (NIUS 01, Asulabs, Neuchatel, Switzerland) were used to measure the systolic (Ds) and diastolic diameter (Dd) and derive three indices of compliance and storage capacity: systolo-diastolic variation of cross sectional area VSCA = tau [(Ds2/4)-(Dd2/4)] mm2, operative arterial compliance CA = tau Dd (Ds-Dd)/2 (PAS-PAD) in mm2/mmHg. RESULTS: 1. In NT, Ds and Dd increased significantly with age (p < 0.01), likewise the VSCA, and CA (p < 0.002). 2. In HT and DTI, when age was taken into account, the Ds and Dd were significantly greater than in control but VCSA and CA were higher in HT and lower in DT. CONCLUSION: Similar to ageing changes in NT, HT lead to increase in medium-size radial artery the diameter and storage capacity, while to decrease in DT. This suggests that opposite cardiovascular load induce opposite modifications in arterial wall structure leading to reduce the wall stress.

Adult↗
PubMed1992

Use of a microprocessor-equipped tablet box in monitoring compliance with antihypertensive treatment.

Compliance with antihypertensive therapy is usually monitored by questionnaire, tablet counts, or estimation of drug levels in blood or in urine. The aim of this study was to examine patient compliance by means of an "electronic monitor." After 2 weeks of run-in on placebo, 34 moderately hypertensive patients were included in an open, randomized, crossover trial examining the efficacy and tolerance of nitrendipine, 20 mg as a single daily dose (morning or evening) for 1 month. We analyzed the results in 26 patients. Patients were supplied with tablet boxes equipped with a microprocessor (MENS) that registered the timing and duration of opening of the box over both the placebo and nitrendipine periods. Compliance (%) was calculated as the ratio of the number of days that the pill box was opened to the number of days between visits. The compliance was analyzed for each treatment group, namely placebo and nitrendipine morning and evening, over 1 month. Compliance (mean + SD) was 96.5 +/- 7.4% on placebo and 94.4 +/- 10.7% in the morning and 90.6 +/- 15.4% in the evening. Nitrendipine was taken in the morning at 0700 h +/- 2 h and in the evening at 1859 h +/- 2 h 12 min. The frequency of 24 h +/- 1 h intervals between medication was 83.5% on placebo. This frequency was 72.6% for morning dosage and 71.8% for evening dosage on nitrendipine. There were no differences in compliance between the morning and evening groups when analyzed according to age and sex. There was a negative correlation with time (r = -0.57, p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Pressure↗
PubMed1992

Use of ambulatory blood pressure monitoring in the management of antihypertensive therapy.

The recent development of ambulatory blood pressure (ABP) monitoring techniques has improved recording of blood pressure in therapeutic trials and in the clinical setting. The application of ABP differs according to which of these 2 applications is being considered. In therapeutic trials, a placebo control is required. The large quantity of precise data acquired with ABP monitoring allows the study of a limited number of patients; it also allows individual study of patients with a 'white coat' response (i.e. elevated blood pressure in response to examination by the clinician). Analysis of data from ABP monitoring may include the following: comparison of mean blood pressure values over 24 hours, daytime or night-time, or over any other selected time period; 24-hour blood pressure profiles, or analysis hour-by-hour, giving true chronotherapy, and providing data regarding the wearing-off of a drug effect or loss of therapeutic control; analysis of blood pressure at particular times, such as on waking; or specific examination of nonresponders. In individual patients, ABP monitoring should be reserved for specific indications. It can be used before initiation of treatment to confirm the necessity for treatment, especially in the context of hypertension at rest or the 'white coat' effect. With established treatment, ABP monitoring can be used in patients with resistant hypertension, in severe hypertension to examine loss of blood pressure control over time or inversion of the day/night cycle, and in patients with a specific illness, e.g. diabetes, in order to obtain the lowest blood pressure readings possible. Examination of these factors assists clinicians to accurately decide upon the timing and frequency of antihypertensive therapy.

Blood Pressure Monitors↗