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G Chatellier

Publications and source records attributed to G Chatellier.

At least 145 records · Page 8Linked to original sources

Short report: HYPERGENE: a clinical and genetic database for genetic analysis of human hypertension.

OBJECTIVE: Genetic studies of essential human hypertension require the recording and management of numerous data concerning multiple hypertensive families. The present report describes a new family database, HYPERGENE, and demonstrates its potential usefulness in such a complex disease. METHODS: The database was implemented on an Apple Macintosh computer using the 4TH DIMENSION software program. Through a user-friendly interface, it offers a high-quality data record, easy data retrieval and compatibility with other software. PATIENTS: HYPERGENE contains a prospective collection of 187 families with at least two hypertensive sibs (826 subjects). Each subject was analysed according to the same protocol. To allow definition of clinical and biological phenotypes and genetic analysis, clinical and biological data were recorded and, at the same time, plasma, urine and DNA libraries were stored. RESULTS: Probands were 50.6 years old with an early onset (39.1 years of age) of hypertension (157.7/97.8 mmHg); 125 had moderate-to-severe hypertension. According to our selection criteria, only one out of 187 sibships had familial dislipidaemic hypertension. Of the living fathers, 45% were examined, and 54% of the living mothers: 48.6% had an onset of hypertension before age 50 years. Children (mean age 28.7 years) of hypertensive sibs presented a high percentage of hypertension (8.3%). CONCLUSION: The HYPERGENE database facilitates data storage and analysis on familial hypertension, and should prove a useful tool for assessing molecular biology results in the field of hypertension and for allowing collaborative research.

Adult↗

Blood pressure effects of acute intravenous renin or oral angiotensin converting enzyme inhibition in essential hypertension.

OBJECTIVE: To assess the participation of the renin-angiotensin system in the blood pressure regulation of essential hypertensive patients through acute specific renin inhibition. DESIGN AND METHODS: Fifty-three consecutive untreated hypertensive patients (mean +/- SD age 55 +/- 10 years, 42 male) were investigated on their usual sodium diet in a 3-h protocol. The first 11 patients did not receive any drug, the following 20 patients ingested a single oral dose of captopril (1 mg/kg) and the last 22 patients received a renin inhibitor infusion (remikiren; 1 mg/kg over 60 min). RESULTS: The maximum diastolic blood pressure fall was comparable in the two treated groups. Diastolic blood pressure changes analysed as area under the curve were similar for both drugs (overall F1,40 = 1.26, P = 0.27). Even though the baseline renin levels were within the narrow range 5-80 pg/ml, the diastolic blood pressure fall analysed as area under the curve from time 32 min to time 60 min was significantly correlated with the baseline active renin level in both groups (remikiren r = 0.44, P < 0.05; captopril r = 0.47, P < 0.05). The plasma active renin levels were significantly increased at 30, 90 and 120 min in both groups, and the maximum active renin levels were significantly correlated with the baseline active renin level (remikiren r = 0.62, P < 0.01; captopril r = 0.66, P < 0.01). The plasma prorenin levels did not change. CONCLUSIONS: This study suggests that acute renin inhibition and acute angiotensin converting enzyme inhibition similarly decrease the blood pressure and increase the plasma active renin levels. Acute blockade of the renin-angiotensin system at its initial step by a renin inhibitor can therefore be used to investigate the renin dependence of the blood pressure in essential hypertension.

Administration, Oral↗

The vanishing ECG.

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Copying Processes↗

Accuracy and reproducibility of left ventricular mass measurement by subcostal M-mode echocardiography in hypertensive patients and professional bicyclists.

In some patients, left ventricular (LV) mass cannot be evaluated by M-mode echocardiography because the parasternal long-axis view is not available. The aim of this study was to determine whether the subcostal view obtained by M-mode echocardiography under 2-dimensional guidance allows accurate and reproducible LV mass determination. Using the cube formula, LV mass was calculated, from parasternal and subcostal views in 96 subjects: 73 hypertensives and 23 professional bicyclists, covering a wide range of LV dimensions. M-mode tracings were read by 2 experienced echocardiographers and the interobserver variability was evaluated. With use of the subcostal view, the interobserver reproducibility, expressed as observer 1-observer 2, was excellent: -0.3 +/- 1.3 mm for LV diastolic diameter, -0.1 +/- 1.0 mm for ventricular diastolic septal thickness, 0.2 +/- 0.6 mm for diastolic free wall thickness and 0.03 +/- 16.7 g for LV mass. In 96% of cases, the difference in LV mass between the 2 observers did not exceed 30 g. With use of the parasternal and subcostal approaches, LV mass was not statistically different (202.6 +/- 2.2 g and 206.5 +/- 2.0 g, respectively) and the difference was < 52 g (clinically significant threshold) in 91 of 96 cases. It is concluded that, using the cube formula, LV mass calculation based on the subcostal view was accurate and not statistically different from that provided by the usual parasternal approach.

Adult↗

Comparison of reduction in microalbuminuria by enalapril and hydrochlorothiazide in normotensive patients with insulin dependent diabetes.

OBJECTIVE: To compare the effects of sodium depletion and of angiotensin I converting enzyme inhibition on microalbuminuria in insulin dependent diabetes. DESIGN: Randomised, double blind, double dummy parallel study of normotensive diabetic patients with persistent microalbuminuria (30-300 mg/24 h) treated with enalapril or hydrochlorothiazide for one year after a three month, single blind placebo period. SETTING: Diabetic clinic in a tertiary referral centre. PATIENTS: 10 diabetic patients with low microalbuminuria (30-99 mg/24 h) and 11 with high microalbuminuria (100-300 mg/24 h). INTERVENTIONS: 11 subjects (six with low microalbuminuria, five with high microalbuminuria) were given enalapril 20 mg plus placebo hydrochlorothiazide once daily and 10 (four with low microalbuminuria, six with high microalbuminuria) hydrochlorothiazide 25 mg plus placebo enalapril once daily. MAIN OUTCOME MEASURES: Monthly assessment of urinary albumin excretion and mean arterial pressure; plasma active renin and aldosterone concentrations and renal function studies at 0, 6, and 12 months. RESULTS: Median urinary albumin excretion decreased from 59 (range 37-260) to 38 (14-146) mg/24 h with enalapril and from 111 (33-282) to 109 (33-262) mg/24 h with hydrochlorothiazide (analysis of variance, p = 0.0436). During the last three months of treatment with enalapril five patients had persistent normoalbuminuria (2-3 times below 30 mg/24 h), five low microalbuminuria, and one high microalbuminuria; in the hydrochlorothiazide group one had normoalbuminuria, three low microalbuminuria, and six high microalbuminuria (chi 2 test = 6.7; p = 0.03). Mean arterial pressure did not differ before (98 (SD 7) with enalapril v 97 (9) mm Hg with hydrochlorothiazide) or during treatment (88 (7) with enalapril v 90 (7) mm Hg with hydrochlorothiazide (analysis of variance, p = 0.5263)). Glomerular filtration rate did not vary. The aldosterone to active renin ratio was decreased by angiotensin I converting enzyme inhibition and increased by sodium depletion, showing treatment efficacy. CONCLUSION: Angiotensin I converting enzyme inhibition by enalapril effectively reduces microalbuminuria in normotensive diabetic patients whereas hydrochlorothiazide is not effective. Changes in blood pressure and activity of the renin-angiotensin-aldosterone system may contribute to these different effects.

Adolescent↗

Left ventricular mass and geometry before and after etiologic treatment in renovascular hypertension, aldosterone-producing adenoma, and pheochromocytoma.

To study left ventricular (LV) geometry in secondary hypertension and its evolution following etiologic treatment, echocardiography was performed in a total of 73 patients: 40 patients with renovascular hypertension (RVH), 21 with aldosterone-producing adenoma (APA), and 12 with pheochromocytoma (PH). Repeat echocardiography was possible in 43 of these patients, 3-24 months following curative renal revascularization or adrenal surgery. Age, sex ratio, and initial drug treatment score were comparable in the three etiologic categories, but 24-h ambulatory blood pressure and LV mass index were significantly higher in APA and RVH than in PH. End-diastolic LV volume was significantly smaller in PH than in APA and RVH. After treatment, the greatest reduction in LV mass occurred in APA (-18%, P < .05) and the lowest in PH (-5%, NS). Both patients with APA and those with PH exhibited a significant decrease in LV wall thickness, whereas LV diameter tended to decrease in APA patients and to increase in PH patients. No significant cardiac changes occurred in RVH patients after treatment. Although LV mass index and ambulatory blood pressure were correlated both before and after treatment, LV mass index changes did not correlate with changes in ambulatory blood pressure or with the known duration of hypertension. Systolic function was normal before and following etiologic treatment in the three categories. These findings suggest that, in addition to blood pressure, volume and/or humoral factors influence the pathogenesis of left ventricular hypertrophy and its reversibility.

Adenoma↗

Diagnostica--a Bayesian decision-aid system--applied to hypertension diagnosis.

"Diagnostica" is a Bayesian statistical tool designed to collect and store the patient's data, suggest a diagnosis, and explain the decision in terms of density distributions. The program is written in C language on MacIntosh support. It is described using the case study of differential diagnosis between essential and secondary hypertensions (i.e., fibrodysplastic renal artery stenosis, atheromatous renal artery stenosis, Conn's syndrome, nephropathy and pheochromocytoma). Seventeen experimental parameters were taken into consideration, all of them available during the first medical examination. The density distributions of all items were established from the ARTEMIS experimental database. Both a priori probabilities of different types of hypertension and loss coefficients are taken into account in the calculations. Diagnostica can be used in a "make diagnosis" mode or in an "edition" mode. In the first case it can serve a physician in everyday practice; in the second it becomes a tool for medical research.

Bayes Theorem↗

Restenosis after a first percutaneous transluminal renal angioplasty.

The incidence of restenosis after a first successful percutaneous transluminal angioplasty of a native renal artery and the clinical and angiographic variables that may influence its occurrence were studied in 104 hypertensive patients. Angiograms obtained immediately before and after angioplasty and, in 92 patients, 8.8 +/- 6.0 months after angioplasty were interpreted separately by two observers. Stenosis severity was classified into five grades, and restenosis was defined by a stenosis one grade or more higher at follow-up than immediately after angioplasty. Interobserver concordance for etiology, stenosis grade, and other angiographic items yielded kappa coefficients in the range of 0.328-0.942. Sessions were organized to reach a consensus in each case. Ostial stenoses were more frequent in patients with atheromatous stenoses, and branch stenoses were more frequent in those with fibromuscular dysplasia. There was no significant difference between the 15 patients (16%) with restenosis and those without concerning sex distribution, mean age, mean blood pressure, plasma creatinine level, and etiology distribution. Truncal stenoses were less prone to restenosis than ostial or branch stenoses (12% versus 35%, respectively; 95% confidence interval of difference, -0.6% to 47%). In patients with atheromatous stenoses, aortitis or aortic ectasia were associated with a high restenosis incidence (35% when present versus 8% when absent; 95% confidence interval of difference, 5% to 48%). In conclusion, restenosis was observed in one sixth of patients after a first successful renal angioplasty; its incidence was low in patients with truncal stenoses and high in those with severe aortic atheroma. Automated renal artery stenosis quantification methods are needed to standardize stenosis description.

Adult↗

Cardiac weight in hypertension induced by nitric oxide synthase blockade.

Wistar rats given a nitric oxide synthase inhibitor, NG-nitro-L-arginine-methyl ester (L-NAME), for 4 weeks develop time- and dose-dependent hypertension without cardiac hypertrophy. This initial study of the relation between left ventricular weight and L-NAME-induced hypertension has now been extended by giving 50 mg/kg per day L-NAME to Wistar rats (n = 30) for 8 weeks and comparing results with those from control rats (n = 10) and two-kidney, one clip rats (n = 14). Although L-NAME rats and two-kidney, one clip rats had increased systolic blood pressures during the last 3 weeks of the experiment (202 +/- 24 and 224 +/- 16 mm Hg, respectively), the ratio of left ventricular weight to body weight of L-NAME rats (2.12 +/- 0.32 mg/g) was not statistically different from that of control rats (1.93 +/- 0.13 mg/g), whereas that of two-kidney, one clip rats was increased (2.85 +/- 0.20 mg/g). The plasma renin activity of L-NAME rats was not significantly different from that of control rats. Two L-NAME rat subgroups were defined according to the presence of left ventricular hypertrophy (ratio of left ventricular weight to body weight > 2.19 mg/g, control mean +2 SD) (6 of 25) or its absence (19 of 25). Systolic blood pressure, plasma renin activity, and cardiac angiotensin converting enzyme activity of L-NAME rats with left ventricular hypertrophy were significantly higher than those of the subgroup without.(ABSTRACT TRUNCATED AT 250 WORDS)

Angiotensins↗

Self blood pressure measurement at home.

Forty-six untreated patients measured their blood pressure at home for three weeks using an A and D, UA 751 automatic device, and were examined three times at the outpatient clinic. Home blood pressure was significantly lower than clinic blood pressure, even at the third visit when the correlations between clinic and home values were the most significant. The differences between clinic and home values had a gaussian distribution. The variance analysis of home blood pressure values showed that 67% of the variance was attributable to the between-subject component, 2% to the day effect, 15% to the time of the day effect and 16% to the residual (the measurement error). The standard deviation of the difference between two five-day periods of self blood pressure monitoring at home (5.4 and 4.1 mm Hg) was much lower than what has been reported for clinic measurements or 24-hour ambulatory monitoring.

Adult↗

[Cooperative study of systolic arterial hypertension in the elderly patient (SHEP). Comments].

SHEP (Systolic Hypertension in the Elderly Program) is a multicenter controlled therapeutic trial which included 4,736 subjects aged 60 years and over, who had isolated systolic hypertension at three consecutive visits at the outpatient clinic. The treatment, based on low doses of diuretic (chlorthalidone 12.5-25 mg daily) combined, when necessary, with a cardioselective beta-blocker (atenolol 25 to 50 mg daily), significantly reduced the incidence of cerebrovascular and coronary events; the relative risk reduction for total mortality was not statistically significant. The beneficial cardiovascular effects were observed in both sexes, and in the 80+ age group. These results show that this particular therapy applied to this form of hypertension decreases the risk of both coronary and cerebral events, as was already suggested by the meta-analysis of the controlled therapeutic trials performed with diuretics, beta-blockers and other older antihypertensive drugs in patients with permanent diastolic hypertension. They also show the limitations of this therapeutic strategy, which controlled only 50 percent of the patients who were, however, highly selected, especially concerning the absence of associated morbid conditions and treatments. The need for, and feasibility of, new controlled therapeutic trials comparing the mortality and morbidity associated with various new antihypertensive therapies must now be discussed.

Adrenergic beta-Antagonists↗

Decision to treat mild hypertension after assessment by ambulatory monitoring and World Health Organisation recommendations.

OBJECTIVE: To determine if one ambulatory blood pressure recording over 12 hours could detect those patients with mild hypertension who needed treatment according to the World Health Organisation-International Society of Hypertension (ISH) guidelines based on the causal measurement of diastolic blood pressure at successive visits to a clinic. DESIGN: Comparison of decision to treat based on one ambulatory measurement over 12 hours and standard blood pressure measurements over six months in the same patients. SETTING: Outpatient hypertension clinic. SUBJECTS: 130 men and women with diastolic blood pressure of 90-104 mm Hg at second visit to clinic. MAIN OUTCOME MEASURES: Blood pressure measurements over six months. Measurement from ambulatory monitoring. Decision to treat. RESULTS: Of the 130 patients included, 108 were followed up over the six months. Treatment was started according to WHO-ISH criteria in 44 (13 at the third visit, 13 at the fourth, 18 at the fifth). According to the selected criteria for ambulatory blood pressure monitoring 41 patients would have been treated. Both methods agreed that the same 27 patients required treatment and the same 50 did not, but they did not agree in 31 patients. When calculated at the optimal diastolic blood pressure threshold determined by a receiver operating characteristic curve, the sensitivity, specificity, and positive predictive value of ambulatory blood pressure monitoring were 71% (95% confidence interval 57% to 84%), 82% (72% to 92%), and 66% (51% to 81%), respectively. CONCLUSION: If the WHO-ISH criteria are accepted as the standard for deciding to treat patients with mild hypertension the predictive value of one ambulatory blood pressure recording over 12 hours is too low to detect with confidence those patients who need treatment when managed according to these criteria.

Blood Pressure Determination↗

[Cardiovascular pathology related to aging. Role of prevention].

During the last 50 years the increase of life expectancy has been dramatic in all Western countries. In France, the life expectancy in 1988 was 80.6 years for women and 72.3 years for men. In 1980, the life expectancy at the age of 60 was more than 20 years in women and 16 years in men. Side by side with this increase of life expectancy there has been a change in the structure of the causes of death. Cardiovascular diseases accounted for 15.6 percent of all causes in 1930, 31 percent in 1950 and 37.4 percent in 1980. Cardiovascular diseases therefore rank very high among the causes of mortality, and one of the principal reasons for this is ageing of the population. Studying the epidemiology of cardiovascular ageing is tantamount to determining the part played by prevention in these diseases. There are wide fluctuations in cardiovascular mortality rate according to some demographic variables: men are more affected than women, the poorer subjects more than the richer subjects, and people living in the North of France more than those living in the South. These disparities are real, irrespective of age, and they can be explained, at least partly, by differences in the prevalence of well-known risk factors. Cardiovascular ageing plays a role, probably important, in the genesis of physical and mental disabilities, but markers that would measure them precisely are lacking. The development of such indicators is a major line of research which should make it possible to evaluate the prospective results of a policy of prevention in a segment of the population where people aged 60 or more accounted for 19.1 percent in 1990 and will account for 25 percent in the year 2020.

Adult↗

Treatment of malignant gliomas with surgery, intraarterial chemotherapy with ACNU and radiation therapy.

Forty patients with malignant supratentorial gliomas received iterative intraarterial (IA) infusions of ACNU, 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2-chloroethyl)-3-nitrosourea at a dose of 150 mg repeated every 6 weeks. Group A consisted of eighteen patients previously treated with surgery, radiation therapy (RT) and sometimes chemotherapy, who received IA ACNU at tumor recurrence. Group B consisted of twenty two patients who received IA ACNU in the postoperative pre-RT period. In group A, 8/18 patients (44%) had an objective response, including 6/12 anaplastic astrocytomas (AA) and 2/6 glioblastoma multiforme (GBM), while 10/18 patients (56%) did not respond. Median survival time was 6 months for GBM and 12 months for AA. In group B, 6/22 patients (27%) had an objective response (4/18 GBM and 2/4 AA) and 16/22 patients (73%) did not respond. Nine patients had such an extensive tumor after one or two courses of IA ACNU that RT was cancelled. Median survival time was 8 months for GBM and 8 months for AA. Three patients (8%) had ophthalmologic toxicity on the infused side. There was no case of leukoencephalopathy.

Adult↗

Effect of two French nurses' strikes on mortality in a geriatric hospital.

PURPOSE: To study the influence of the 1988 French nurses' strikes on mortality in a geriatric hospital. MATERIALS AND METHODS: Two nurses' strikes affected the Charles Foix Hospital near Paris from June 29 to July 31 and from September 17 to October 22, 1988. Mortality was studied in nine geriatric wards of this hospital, including two rehabilitation units comprising 187 beds, and seven long-term care units comprising 1,132 beds. Monthly mortality rates were calculated from the hospital's administrative registers and expressed as deaths per 1,000 patient-days. These rates were calculated in each of the aforementioned nine units for the 36 months preceding the first strike (control period) and for the 12 months following it (study period). RESULTS: Over the control period, monthly mortality was significantly higher in rehabilitation units than in long-term care units (2.46 +/- 1.21 versus 0.83 +/- 0.47, p less than 0.001), but mortality rates among rehabilitation units, as well as among long-term care units, were comparable. Also, during the control period, large seasonal fluctuations in monthly mortality rates were observed in both rehabilitation units and long-term care units (peak in winter and nadir in summer). These rates tended to decrease from year to year in rehabilitation units but not in long-term care units. A statistical model based on time-series analysis of the control period data was used to calculate the expected monthly mortality rates for the study period in rehabilitation units and in long-term care units, respectively. Three of the 12 actual monthly mortality rates exceeded the upper limit of the 95% confidence interval of the 12 expected monthly mortality rates, in the units where the more severe care disruption occurred. A detailed analysis of discharge summaries of these units failed to identify a possible link between some of these deaths and a possible absence of care. CONCLUSIONS: The nurses' strikes did not induce a clear-cut increase in mortality in this population of elderly patients. However, we cannot exclude the possibility that these strikes had some negative effects on health. Our results fail to provide answers to the difficult ethical problems created by such stoppages.

Aged↗