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Biomedical subjects

R Fagard

Publications and source records attributed to R Fagard.

At least 415 records · Page 23Linked to original sources
PubMed1982

Increase in plasma aldosterone during prolonged captopril treatment.

Plasma aldosterone concentration was measured in seven patients before and during long-term angiotensin II suppression with captopril. Plasma aldosterone decreased initially from 62 to 9 pg/ml (p less than 0.01) after 1 month of captopril administration. Thereafter, it began to increase and after 1 year reached a level of 163 pg/ml, which significantly (p less than 0.01) exceeded the pretreatment value. During long-term captopril therapy, plasma renin activity remained elevated and plasma angiotensin II concentration suppressed. The mechanism responsible for the late increase in plasma aldosterone during long-term angiotensin II suppression with captopril remains to be elucidated. Body weight decreased initially, parallel to plasma aldosterone increase, but after 6 months increased again to reach its pretreatment level after 1 year. Nevertheless a sizable and lasting hypotensive effect was observed in all patients.

Adult↗
PubMed1982

Response of the systemic pulmonary circulation to labetalol at rest and during exercise.

1 Labetalol was administered to 18 hypertensive patients for an average duration of 2.44 weeks, with an average final daily dose of 1.65 g (principally to study its short-term haemodynamic effects). 2 Labetalol decreased resting heart rate by 16% and maximal exercise heart rate by 21%; the phenylephrine-induced increase in systolic brachial arterial pressure was reduced by 36%. 3 During labetalol treatment brachial arterial pressure was decreased by 29/15 mmHg in the recumbent position, by 41/23 mmHg at rest sitting and by 53/23 mmHg at maximal exercise; total peripheral resistance was not significantly affected at rest recumbent but was reduced at sitting and at exercise; cardiac output was decreased in all conditions. 4 Labetalol reduced mean pulmonary arterial and capillary wedge pressures only in the sitting position. Pulmonary vascular resistance remained unchanged. 5 The drug produced significant decreases in plasma renin activity and in plasma aldosterone concentration.

Adult↗
PubMed1982

Influence of beta adrenergic blockade on effects of physical training in patients with ischaemic heart disease.

Reduction in heart rate during submaximal exercise is often used to judge the progress of patients with ischaemic heart disease in the course of a physical training programme. Some patients, however, are treated with beta adrenergic blocking drugs and it remains controversial if chronic beta blockade influences the effects of training and if heart rate remains a useful guide in the evaluation of the state of training of these patients. Male postinfarction patients, 15 treated with and 15 without beta blockers, were trained for three months, three times a week. Cardiorespiratory results from uninterrupted incremental exercise tests before and after training were compared. In each subgroup, the heart rate and systolic blood pressure were significantly reduced. For heart rate the decrease after training became more pronounced with increasing work load and the overall reduction was significantly less in the beta blocker group compared with the patients not treated with beta blockers. For systolic blood pressure the training-induced reductions were more pronounced in the patients on beta blockers. The increase of peak oxygen uptake was similar in the patients with and without beta blockers, namely 36% and 34.5%. At submaximal exercise carbon dioxide output, pulmonary minute ventilation, and the respiratory exchange ratio were lower after training, and these effects of training were similar whether or not the patients were on beta blockers. The study shows that the usual effects of training are observed in patients on beta blockers, and that heart rate remains a useful guide to their evaluation throughout a physical training programme.

Adrenergic beta-Antagonists↗
PubMed1982

Hemodynamic response to converting enzyme inhibition at rest and exercise in humans.

The response of the systemic circulation to acute inhibition of the converting enzyme with 25 mg of oral Captopril (Squibb) was studied in six normal sodium-replete male volunteers at rest and during exercise, together with its effects on exercise capacity for graded uninterrupted exercise. In recumbent subjects at rest Captopril did not affect arterial pressure or heart rate, and plasma renin activity rose 2.5-fold (P less than 0.05). In subjects in the sitting position, at rest and during exercise until exhaustion, Captopril reduced mean brachial intra-arterial pressure by an average of 7 Torr in comparison to placebo (P less than 0.001). Captopril's hypotensive effect was caused by a reduction of systemic vascular resistance (P less than 0.01), without changes of cardiac output (measured by CO2 rebreathing), heart rate, or stroke volume. Plasma renin activity was significantly higher during Captopril (P less than 0.001). Peak oxygen uptake and exercise duration were the same after administration of Captopril or placebo. The data demonstrate that the renin-angiotensin system is not involved in the homeostasis of blood pressure in supine sodium-replete humans, but has a modest role in blood pressure regulation when posture is changed from supine to upright. The orthostatic effect of Captopril is maintained during upright exercise. Furthermore the reduction of systemic vascular resistance by Captopril does not affect peak oxygen uptake.

Adult↗
PubMed1982

Plasma prostaglandins, renin, and catecholamines at rest and during exercise in hypertensive humans.

Plasma prostaglandins (PGE and PGF alpha), catecholamine concentration, and plasma renin activity (PRA) were measured during an uninterrupted graded exercise test on the bicycle ergometer in 11 hypertensive patients. Blood was withdrawn from the brachial and pulmonary arteries after 30 min of recumbent rest, after 15 min of rest sitting, and at the final work load of the exercise test, which averaged 143 +/- 16.5 W. Exercise did not provoke a significant change in these plasma PGE or PGF alpha concentrations, whereas a rise (P less than 0.001) in arterial PRA and (nor)epinephrine concentration was observed. It is thus unlikely that PGE or PGF alpha is an important determinant of PRA release during exercise, although circulating levels of PGE and PGF alpha do not necessarily reflect release rate or activity in the kidney.

Adult↗
PubMed1982

Response of the systemic and pulmonary circulation to converting-enzyme inhibition (captopril) at rest and during exercise in hypertensive patients.

Twenty sodium-replete patients with hypertension were allocated either to a placebo or to a captopril treatment group. Each patient was investigated in rest-recumbent (RR) and rest-sitting (RS) positions and during an uninterrupted, graded, submaximal exercise test (up to the anaerobic threshold) before treatment, and with a similar protocol 75 minutes after treatment with captopril or placebo on the same morning. Captopril decreased brachial intraarterial pressure by 7/4 mm Hg at RR, by 16/10 mm Hg at RS, and by 19/10 mm Hg during exercise (p less than 0.001), based on a decrease of systemic vascular resistance (p less than 0.001). Slight increases of cardiac output and of heart rate were noted at rest; cardiac output was not significantly affected during exercise, but the increase of heart rate of 2.4 beats/min was significant (p less than 0.01). Captopril decreased pulmonary artery (p less than 0.05) and capillary wedge pressures (p less than 0.001), with unchanged pulmonary vascular resistance. The data indicate that the action of captopril is characterized by arteriolar and possibly venous dilatation both at rest and during exercise. Pulmonary vascular resistance, however, is not affected.

Adult↗
PubMed1982

Antihypertensive therapy in patients above age 60 with systolic hypertension. A progress report of the European Working Party on High Blood Pressure in the Elderly (EWPHE).

1. Although systolic blood pressure elevation is responsible for increased incidence of cardiovascular accidents in old people, the preventive benefit of lowering systolic hypertension in elderly has not been confirmed. 2. A double blind study comparing the effects of a placebo and of an active regimen (hydrochlorothiazide-triamterene with or without methyldopa) in people over 60 years with isolated systolic hypertension has been undertaken by the European Working Party on High blood pressure in the Elderly (EWPHE). 3. The actively treated group shows a lowered sitting blood pressure (-15/6 mm Hg), a mild increase of serum creatine, serum uric acid and blood glucose and a mild decrease of serum potassium after two years of treatment when compared to the spontaneous changes observed in the placebo treated group. 4. The study is continuing to evaluate if the blood pressure reduction prevents or reduces the incidence of cardiovascular accidents, although some biochemical changes were provoked by the treatment.

Aged↗
PubMed1982

Biological significance of active and inactive renin in hypertensive patients.

The significance of active and inactive renin was investigated by comparison of an in vitro assay of active, total and inactive plasma renin concentration (APRC, TPRC, IPRC) and plasma angiotensin II concentration (PA II) with an in vivo change in mean arterial pressure (MAP) produced by angiotensin antagonism with saralasin and by angiotensin converting enzyme blockade with captopril. A significant relationship between the changes in MAP during saralasin and captopril with the pre-treatment level of APRC, TPRC and PA II were found; while the pre-existing level of inactive renin was not a predictor for the hypotensive effect of saralasin and captopril. During captopril and saralasin significant increases in TPRC and APRC were found and no change in IPRC.

Adult↗
PubMed1982

Fluctuations in the plasma angiotensin I converting enzyme activity during long-term treatment with captopril.

Eight hypertensive patients on chronic captopril treatment were studied: blood pressure, plasma converting enzyme activity (pCEA) and various components of plasma renin-angiotensin-aldosterone system were measured repeatedly, immediately before and up to 7 hours after the usual morning dose of captopril in 5 patients, or a matching placebo in 3 patients. In the patients, receiving a placebo no significant changes were observed over a 7 hour period in pCEA, plasma rénin activity (PRA), plasma angiotensin II (ANG II) plasma aldosterone (PAC) and blood pressure. In patients receive captopril (200 mg) pCEA rapidly decreased, reaching after 2 hours a minimum, corresponding to nearly 20 per cent of its reference value. Thereafter pCEA increased and after 7 hours remained only slightly depressed. Within the first hour after captopril intake a small but significant decrease of ANG II and PAC was observed, while PRA and blood pressure remained unchanged throughout the study period. A continuous low pCEA level is therefore not necessary to achieve a sustained blood pressure lowering effect during chronic captopril treatment.

Adult↗
PubMed1982

Influence of anti-hypertensive therapy on serum cholesterol in elderly hypertensive patients. Results of trial by the European Working Party on High blood pressure in the Elderly (EWPHE).

In the European Working Party trial on High blood pressure in the Elderly, patients over 60 are randomly allocated either to receive diuretic capsules containing 25 mg hydrochlorothiazide and 50 mg triamterene or matching placebos. If the blood pressure remains high those receiving active diuretic treatment also receive methyldopa. Those receiving a placebo diuretic area given placebo methyldopa tablets. The study is double blind, started in 1974 and is still in progress. Three hundred and thirty-one patients have now been followed for 1 year and of these 190 have been followed for 2 and 90 for 3 years. After 1 year the serum cholesterol in the placebo group fell by an average of 10.4 mg/100 ml; over 2 years the fall was 16.0 mg/100 ml and over 3 years 20.8 mg/100 ml (6.7%). The corresponding results for the actively treated group were falls of 3.1 mg/100 ml; 20.3 mg/100 ml and 17.3 mg/100 ml (6.6%). Over a period of up to 3 years the average fall in cholesterol was 5.9 mg/100 ml/year in the placebo group and 5.0 mg/100 ml/year in the actively treated group. Thus the changes in serum cholesterol were similar whether the patients received active or placebo medication. In particular there was no evidence for an increase in cholesterol nor for a smaller decrease during diuretic therapy. In the actively treated group the fall in blood pressure in the more hypertensive patients was accompanied by a fall both in haematocrit and serum cholesterol. In patients with less severe hypertension, active treatment was not accompanied by a fall in either hematocrit or cholesterol. These different responses of serum cholesterol in the more and less severe hypertensives in the present study could explain some of the previous conflicting reports on the influence of diuretic treatment on serum cholesterol.

Aged↗
PubMed1982

Anaerobic threshold for long-term exercise and maximal exercise performance.

The anaerobic threshold during graded exercise (GXT, AT1) was determined as the exercise level initiating a curvilinear increase in ventilation (VE), and during prolonged exercise (PXT, 40 min, AT2) as the maximal exercise level where still a steady state for VE can be reached. Subjects were 8 healthy males, 20 to 53 years of age. Maximal exercise capacity was estimated by means of 1) VO2 max 2) max time on bicycle ergometer at 200 Watts and 3) maximal distance run within 12 min (Cooper test). VO2 max was significantly related to AT1, GXT (r = 0.85, 0.01 less than p less than 0.001) and to AT2, PXT (r = 0.75, 0.05 less than p less than 0.01). Also a significant correlation was found between the endurance exercise capacity (= 200 Watts) and both AT1 (r = 0.80; 0.05 less than p less than 0.01) and AT2 (r = 0.84; 0.01 less than p less than 0.001). Finally only AT2 was significantly correlated with the Cooper test (r = 0.81; 0.01 less than p less than 0.001), no significant relationship was found for AT1 (r = 0.68; p less than 0.05). In conclusion AT1 reached the highest correlation with a short maximal exercise test such as VO2 max, in contrast to AT2, which showed the highest correlation with endurance exercise such as Cooper test or maximal exercise time at 200 Watts.

Adult↗
PubMed1982

The relative effect of mental and physical activity on blood-pressure and heart rate during the waking-up process.

1. The morning rise in blood pressure and heart rate was studied in 18 patients with mild blood pressure elevation. Passing from sleep to the drowsy state raised blood pressure and heart rate very little while the awake state (reading a newspaper sitting in bed) increased the mean blood pressure by 13.2 mm Hg and the heart rate by 5.7 beats per minute. 2. Subsequent application of mental stress (arithmetic) in one third of the patients or physical activity in the upright position in another third showed a different pattern of response. Mental stress mainly raised the blood pressure while physical activity in the upright position mainly raised the heart rate.

Activity Cycles↗