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P Gosse

Publications and source records attributed to P Gosse.

At least 55 records · Page 3Linked to original sources
PubMed1998

[Heart rate: risk factor, risk marker].

When a correlation between an individual characteristic and the incidence of a disease is detected in epidemiology, this characteristic must satisfy four criteria before it can be considered to be a risk factor it must be strongly associated, universally associated regardless of the population, gender, race, associated independently of already recognized factors, especially age, and a cause-and-effect relationship must be demonstrated by a study influencing this characteristic. The first three criteria define the risk marker. Various examples are given, including that of heart rate and overall and cardiovascular morbidity and mortality.

Cardiovascular Diseases↗
PubMed1998

[Evaluation of the cardiovascular risk in hypertensive patients: left ventricular hypertrophy].

Left ventricular hypertrophy is associated with a high risk of cardiovascular complications in all the populations in which it has been studied, especially in hypertensive patients. The echocardiographic measurements of left ventricular mass provides a quantitative approach to this risk, independent of the classical cardiovascular risk factors. It is very tempting to wish to replace the measurement of risk factors which, due to their great variability, are not easy to assess (blood pressure) by a marker which integrates several of them (blood pressure, age, weight, salt intake, blood viscosity, serum cholesterol ...) and their variation with respect to time. However, it is too early to recommend this practice for routine use. M mode echocardiographic measurement of left ventricular mass is relatively difficult technique feasible only in about 80% of the population. Even in the hands of experts, its reproducibility is far from perfect. Technical developments may lead to improvement. It remains to be demonstrated that the use of these values improves the management of hypertensive patients and this will not be an easy task. However the follow-up of left ventricular mass during treatment may be an alternative to trials of morbi-mortality in hypertensive patients with the advantage of requiring a shorter follow-up period and fewer patients. It also remains to be demonstrated that regression of left ventricular hypertrophy is accompanied by a corresponding reduction in cardiovascular complications.

Age Factors↗
PubMed1997

[Diagnosis of Conn's adenoma. Comparative study of x-ray computed tomography and scintigraphy using 19-noriodocholesterol].

OBJECTIVE: In order to differentiate an aldosterone producing adenoma (APA) and a bilateral adrenal hyperplasia (BAH) in case of primary hyperaldosteronism, an adrenal CT-scan is usually used as first line exploration. The contribution of adrenal 19-noriodocholesterol (NP59)-scintigraphy is controversial. PATIENTS AND METHODS: We describe 17 cases of primary hyperaldosteronism referred to surgery for suspected APA. The value of abdominal CT-scan and of adrenal scintigraphy was studied. RESULTS: After unilateral adrenalectomy, 15 cases with confirmed APA were cured and 2 cases with an unilateral hyperplastic macro nodule showed persistence of the disease. The pathologic findings were concordant with CT-scan in 76% (13/17) and with scintigraphy in 88% (15/17). Similar sensitivity was found for CT-scan and scintigraphy (86% and 88%) with 2 false negative results with both techniques. False positive results were observed only with CT-scan (2 cases) suggesting that scintigraphy has a better specificity. No case was misdiagnosed by both techniques. CONCLUSION: These results suggest that NP59-scintigraphy is complementary to adrenal CT-scan for the recognition of APA and is particularly useful in case of a unilateral hyperplastic macro nodule mimicking an APA.

19-Iodocholesterol↗
PubMed1997

Left ventricular mass is better correlated with arising blood pressure than with office or occasional blood pressure.

The peak incidence of cardiovascular complications in the morning points to a possible role of the abrupt increase in blood pressure on arising. However, there is as yet no firm evidence linking the extent of the elevation in blood pressure on arising and the risk of cardiovascular complications. We sought a correlation between blood pressure on arising and left ventricular mass in a population of 181 previously untreated hypertensive patients. Ambulatory blood pressure was measured over a 24-h period, and each patient was requested to trigger a blood pressure determination immediately after standing on arising in the morning. Left ventricular mass was measured with M-mode echocardiography and indexed for height, height(2.7), and body surface area. The systolic blood pressure on arising was significantly (P <.01) better correlated than office blood pressure with left ventricular mass index and wall thickness. On multivariate analysis, the values of systolic blood pressure on arising and mean 24-h systolic blood pressure contributed significantly and independently to the correlation with left ventricular mass and wall thickness. These observations point to the significance of the arising blood pressure. A marked abrupt daily elevation in blood pressure on arising, then maintained for a certain time, could contribute to the development of left ventricular hypertrophy and may constitute a trigger for cardiovascular complications.

Adolescent↗
PubMed1997

Prognostic value of ambulatory measurement of the timing of Korotkoff sounds in elderly hypertensives: a pilot study.

Alteration in the physical properties of the large arteries is probably an important contributory factor in morbidity and mortality in the elderly as well as in patients with hypertension or diabetes. We have developed a simple method based on the ambulatory measurement of the timing of Korotkoff sounds (QKD interval), together with blood pressure, to assess these properties. We report its prognostic value in a retrospective survey of elderly hypertensives. We included in this study 134 hypertensive patients over 45 years of age with no cardiovascular complications, either receiving placebo or prior to treatment with antihypertensive medication and seen between January 1992 and July 1993. In June 1995, a survey was carried out to determine outcome by contacting the patients themselves and their family physicians. Data on outcome were obtained for 111 patients with a mean follow-up period of 30 +/- 8 months. At least one cardiovascular complication was recorded during the follow-up period in 14 patients. From the Cox model, data obtained from QKD monitoring, namely the QKD(100-60), was the best predictor of complications and remained significant (P < .01) even after introduction of age, mean 24 h SBP, gender, and smoking into the model. A QKD(100-60) below 187 msec was accompanied by a relative hazard of cardiovascular complications adjusted for age and mean 24 h BP of 7.3 (95% confidence interval: 2.9 to 11.7). The indices provided by the ambulatory measurement of QKD interval are significant predictors of cardiovascular complications independently of age and BP. This new method seems to add useful information to classic ambulatory blood pressure monitoring. However this will require confirmation in a large prospective study.

Aged↗
PubMed1997

Alteration of arterial distensibility in systemic sclerosis.

OBJECTIVES: To evaluate the distensibility of large arteries in patients with systemic sclerosis (SSc). DESIGN: Prospective case-control study including unselected patients with SSc. SETTING: One cardiology and two internal medicine units in a teaching hospital. SUBJECTS: Eighteen patients with SSc and controls matched for age, sex, height, weight and 24-h ambulatory blood pressure (BP). INTERVENTION: The timing of Korotkoff's sounds (QKD interval), a newly described noninvasive ambulatory method was used to measure arterial distensibility during 24 h. MAIN OUTCOME MEASURES: Two endpoints were used: QKD 100-60 (normalized for a heart rate of 100 beats min-1 and a systolic BP of 100 mmHg) and the slope of QKD against pulse pressure. RESULTS: The patients with SSc had a lower slope of QKD against pulse pressure than the controls (median 0.55, range 0-1.21, versus 0.92, range 0.5-1.34, respectively; P = 0.003), and a lower QKD 100-60 (medians/ranges respectively 191 [162-216] and 203 [169-231]: P = 0.01). CONCLUSIONS: These results indicate that arterial distensibility of large arteries is decreased in SSc.

Adult↗
PubMed1997

Nocturnal blood pressure fall on ambulatory monitoring in a large international database. The "Ad Hoc' Working Group.

A wide range of definitions is used to distinguish subjects in whom blood pressure (BP) falls at night (dippers) from their counterparts (nondippers). In an attempt to standardize the definition of nondipping, we determined the nocturnal BP fall and night-day BP ratio by 24-hour ambulatory monitoring in 4765 normotensive and 2555 hypertensive subjects from 10 to 99 years old. In all subjects combined, the systolic/diastolic nocturnal fall and corresponding ratio averaged (+/- SD) -16.7 +/- 11.0/ -13.6 +/- 8.1 mm Hg and 87.2 +/- 8.0%/83.1 +/- 9.6%, respectively. In normotensive subjects, the 95th percentiles were -0.3/-1.1 mm Hg for the nocturnal fall and 99.7%/98.3% for the night-day ratio. Both the fall and ratio showed a curvilinear correlation with age. The smallest fall and largest ratio were observed in older (> or = 70 years) subjects. A higher BP on conventional sphygmomanometry was associated with a larger systolic (partial r = .11) and diastolic (r = .12) nocturnal BP fall. The diastolic (r = .08) but not the systolic night-day ratio increased with higher conventional BP. The nocturnal BP fall was larger and the corresponding night-day ratio smaller in oscillometric (n = 5884) than in auscultatory (n = 1436) recordings, in males (n = 3730) than in females (n = 3590), and in Europe (n = 4556) than in the other continents (n = 2764). The distributions of the nocturnal BP fall and night-day ratio showed considerable overlap among normotensive and hypertensive subjects, but the overlap tended to be larger for the ratio than for the fall. Of all subjects, 3.2% had systolic and diastolic ratios of 100% or more. With adjustments applied for confounders, the probability of being a nondipper increased 2.8 times (95% confidence interval, 2.0-4.0) from 30 to 60 years and 5.7 times (4.4-7.4) from 60 to 80 years. The odds ratios were 1.0 (0.8-1.4) for males versus females. 1.6 (1.2-2.1) for subjects with definite hypertension versus normotensive subjects, 2.4 (1.2-4.7) for Asians (n = 2213, 96% Japanese) versus inhabitants of the other continents, and 2.4 (1.5-3.8) for subjects examined with auscultatory versus oscillometric devices. In conclusion, the mathematical definition of nondipping, ie, having a night-day ratio of 100% or more for systolic and diastolic BPs, closely approximated the 95th percentiles of the night-day ratio in normotensive subjects. The ratio depends less on BP level than the nocturnal BP fall and is therefore to be preferred in the definition of dipping status. Notwithstanding the present findings, the reproducibility of nondipping and its prognostic significance need further clarification.

Adolescent↗
PubMed1997

Ambulatory blood pressure and left ventricular hypertrophy.

The relation between ambulatory blood pressure and left ventricular mass has been studied with three main aims. The first aim was to validate this new technique for measuring blood pressure. Most studies have shown that the left ventricular mass is correlated more closely to the ambulatory blood pressure than it is to the office blood pressure. The second aim was to define the parameters of most interest in ambulatory recordings. Although the mean 24 h blood pressure has emerged as the parameter of most clinical interest, other parameters, such as the blood pressure measured during activity, the difference between daytime and night-time values and the blood pressure measured when the subject arises in the morning, may also be of value. The interest of these parameters awaits confirmation in prospective studies. Random peak pressures and the variability as determined by discontinuous measurements using non-invasive methods appear to be of little value. The third aim was to assess the value of ambulatory monitoring in identifying the role played by mechanical as opposed to genetic, humoural and hormonal factors in the development of left ventricular hypertrophy in the hypertensive patient. Ambulatory blood pressure monitoring might prove of particular value in assessing the true impact of blood pressure reduction by antihypertensive therapy on left ventricular hypertrophy.

Journal Article↗
PubMed1997

[Echocardiographic measurement of left ventricular mass associating data of the M and 2D modes].

Calculation of left ventricular mass by M mode echo is based on the assumption that the geometry of the left ventricle is an ellipsoid, the long axis of which is twice that of its short axis. The hypothesis in not always true and often leads to overestimation of the ventricular mass. The authors propose a method combining M mode data (end diastolic dimension, septal and posterior wall thickness) and 2D measurement of the left ventricular long axis: the left ventricular mass was measured by Devereux's and the authors' methods in 185 hypertensives. The 2D measurement of the long axis (mean: 84.7 mm) was much smaller than twice the short axis (mean: 52.3 mm) and the two measurements were poorly correlated. Measurement of the long axis was reproducible. The two methods of calculation were closely correlated (r = 0.95) but, on average, 23% lower with the authors' method. These results seem to be more closely related to ambulatory blood pressure than those of the classical method. The authors' combined method takes into account the true geometry of the left ventricle better than M mode method alone and avoids overestimation of left ventricular mass and the prevalence of excentric left ventricular hypertrophy in hypertensive patients.

Adult↗
PubMed1996

Daytime and nighttime ambulatory blood pressures should be calculated over the true sleep/waking cycle and not over arbitrary periods.

The present study was done to compare the values of mean daytime and nighttime blood pressure (BP) calculated over arbitrary periods to those calculated over the true retiring and rising times of the individual patients. A total of 88 individuals, including 55 untreated hypertensives (office BP > 140/90 mm Hg) and 33 normotensives, were recruited. Ambulatory BP was monitored over 24 h during the normal routine of the patient. The patient was requested to trigger a recording on going to bed and on rising in the morning to clearly identify these periods. The mean daytime and nighttime values were calculated over arbitrarily defined periods (6 AM to 10PM daytime and 10 PM to 6 AM nighttime) and as a function of the true retiring and rising times of the individual patients. The true daytime BP was significantly higher than the value calculated over the arbitrary period and the true nighttime BP was significantly lower than the value calculated between 10 PM and 6 AM (paired t test, P < .05). Employing a cutoff value of 135/85 mm Hg for daytime BP, a significant proportion of patients classified as normotensive when daytime BP was calculated over arbitrary periods were in fact classified as hypertensive from the values calculated over true retiring and rising times.

Adult↗
PubMed1996

Regression of left ventricular hypertrophy as a surrogate end-point for morbid events in hypertension treatment trials.

OBJECTIVE: To assess whether regression of left ventricular hypertrophy (LVH) can be used as a surrogate end-point for morbid events in hypertension treatment trials. DESIGN AND METHODS: Statistical, epidemiologic and treatment trial literature was reviewed to identify the criteria that should be met by a surrogate end-point and to determine whether these criteria are met by existing data on the regression of LVH. RESULTS: Relevant criteria include: (1) a consistent relationship between LVH and subsequent morbid events; (2) prediction of lower or higher complication rates by LVH regression or progression; (3) evidence that the relationship between LVH regression/progression and morbidity/mortality is consistent in different populations and with different treatments; and (4) demonstration of a quantitative relationship that allows prediction of a change in clinical risk from a measured change in LVH. The results of seven electrocardiographic and 10 echocardiographic studies with a total of about 20000 subjects have shown consistently higher risks of morbid events in subjects with than without LVH (odds ratios 1.4-5.4). The available data (four studies, 1145 subjects) suggest that morbid events will occur in a higher proportion of subjects in whom LVH progresses (13-59%) rather than regresses (7-12%). However, the latter data are derived almost entirely from white subjects, predominantly male, with incomplete knowledge of interim treatment and blood pressure in most instances; no information on the mathematical relationship between change in LVH and subsequent morbidity and mortality is yet available. CONCLUSIONS: A strict definition of the information required to establish a fully adequate surrogate end-point for morbid events in antihypertensive has been partially but not completely satisfied. The consistent relationship between baseline LVH and subsequent morbid events and the initial evidence of a parallelism between LVH change and prognosis need to be supplemented by additional studies that examine the latter relationship in diverse populations under varied treatments, and which examine the quantitative relationship between measured change in LVH and the subsequent rates of morbid events. Additional data will come from ongoing treatment trials (approximately 12 000 subjects) and observational studies (approximately 8000 subjects) with serial assessments of LVH.

Antihypertensive Agents↗
PubMed1996

Diagnosis of renovascular hypertension: feasibility of captopril-sensitized dynamic MR imaging and comparison with captopril scintigraphy.

OBJECTIVE: Angiotensin-converting enzyme inhibitors may decrease glomerular filtration rate when a significant renal artery stenosis is present. The purpose of this preliminary study is to evaluate the feasibility of captopril-sensitized, dynamic MR imaging of the kidney in a series of patients with a high suspicion of renovascular hypertension and to compare the results with those of captopril scintigraphy. SUBJECTS AND METHODS: Fifteen hypertensive patients with renal artery stenosis shown by angiography were studied with sequential gadolinium-enhanced MR imaging after oral administration of 50 mg of captopril, an inhibitor of angiotensin-converting enzyme. Symmetry of onset and evolution of tubular phases between the two kidneys were analyzed, and medullary signal intensity time curves were drawn for each kidney. When asymmetry between kidneys was noted, the same dynamic study was repeated 24 hr later, without captopril sensitization. All patients also underwent renal scintigraphy after administration of captopril to compare captopril-induced changes in both techniques. Three-dimensional time-of-flight MR angiography was also performed on all patients. RESULTS: MR imaging with normal and symmetric tubular phases showed that 11 patients had no impairment of glomerular filtration after administration of captopril. MR imaging showed that four had impairment of glomerular filtration: studies without captopril were symmetric (n = 2) or slightly asymmetric (n = 2), but administration of captopril induced severe functional impairment on the side of stenosis--that is, a delayed tubular phase with late corticomedullary decrease of signal intensity in the first two patients and absence of tubular phase in the other two. The results of scintigraphy were concordant in all but one case, in which the segmental distribution of filtration impairment, shown by MR imaging, was not shown by scintigraphy. The renal artery stenosis was shown by MR angiography in 10 of 15 patients (67%). CONCLUSION: Captopril-sensitized dynamic MR imaging of the kidney is feasible in patients with renovascular hypertension. However, captopril-induced changes are not present in all patients proven to have the disease. Scintigraphy provides similar results but may ignore segmental functional involvement.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1996

Beyond blood pressure measurements: monitoring of the appearance time of Korotkoff sounds.

We have recently proposed a new method to evaluate the physical properties of arteries based on measurement of the QKD interval together with blood pressure and heart rate with an ambulatory blood pressure monitoring device. This interval is the time between the onset of the depolarization (QRS) on the electrocardiogram (Q) and detection of the last Korotkoff (K) sound at the level of brachial artery during cuff deflation, corresponding to diastolic blood pressure (D). The QKD interval is the sum of the pre-ejection period and of the pulse transmission time from the aortic valves and the microphone. Thus, it is linked to the pulse wave velocity on an arterial segment which includes the ascending aorta and a portion of the subclavian and brachial arteries. From each 24 h monitoring, the average 24 h QKD, the slope of variation of QKD against blood pressure and a normalized QKD (QKD100-60) for systolic blood pressure of 100 mmHg and heart rate of 60 beats/min are calculated. Stiffer arteries as observed with ageing or hypertension are characterized by the reduction of these three parameters. The reproducibility of this method is good. In a pilot study of elderly hypertensive patients we have shown that QKD 100-60 has a strong and independent predictive value for future cardiovascular events. Therefore, this method may add significant information to ambulatory blood pressure monitoring.

Journal Article↗
PubMed1996

Methods of measurement.

Four points, I feel, have dominated the session devoted to the methods of measurement; First, we all seem to be convinced that ambulatory measurement of blood pressure shows great promise, not only in clinical trials of drugs but also in routine practice. Further development of the technique will almost certainly encourage more manufacturers to produce machines, which by the operation of market forces should lead to lower prices. However, we need to be critical with respect to instrument quality and to the rigour of validation according to the guidelines of hypertension societies, especially for particular populations such as elderly patients. Second, two methods of indirect measurement of blood pressure are now being employed, namely auscultation and oscillometry, which are likely to remain the most widely exploited ones with the current technology. They should not be regarded as competing methods because both have their role to play in the measurement of ambulatory blood pressure, with their own advantages and limits. A possible development would be intelligent machines using both techniques, which could switch between methods depending on the actual conditions of each measurement. Third, desirable features of the new machines would be: more comfortable recording conditions for the patient with a lighter, quieter device giving a faster reading and thus reducing the cuff inflation time; and assistance with interpretation, which I believe is compatible with current technology such as automatic determination of the position of the patient (upright or supine) using some form of sensor and quantification of the degree of activity of the patient, which clearly affects blood pressure. Fourth, it is also likely that future development will include devices capable of measuring blood pressure together with other parameters the variations of which according to blood pressure changes may be of great interest, such as electrocardiographic data, oxygen saturation and the QKD interval. For all these reasons, the near future will certainly see much progress in the ambulatory measurement of blood pressure.

Journal Article↗
PubMed1996

[Catheter ablation and modulation of the atrioventricular junction; current aspects].

Ablation of the atrioventricular junction consists in creating a therapeutic AV block to facilitate the treatment of symptoms caused by atrial arrhythmias refractory to drug therapy. The technical performance of ablation has been improved by restricting the indication to atrial fibrillation, by using radiofrequency currents, by choosing a nodal rather than His bundle ablation site, and by improving the function of cardiac pacemakers (rate adapting, back-up). The functional results are excellent but the outcome is punctuated by rare cases of sudden death, the cause of which is not fully understood (dependance, ventricular arrhythmias, ...). To avoid permanent pacing, it has been suggested that atrioventricular conduction should be modulated rather than completely interrupted. Modulation of the fast pathway has been shown to be ineffective; that of the more complex, slow pathway, seems to be more promising. Although this obviates the need for a pacemaker, it does not suppress irregularity of the ventricular rhythm, the main cause of symptoms in paroxysmal atrial fibrillation and of the haemodynamic changes associated with permanent atrial fibrillation.

Actuarial Analysis↗