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1.
J Psychiatr Ment Health Nurs ; 14(6): 527-34, 2007 Sep.
Article de Anglais | MEDLINE | ID: mdl-17718724

RÉSUMÉ

Mental health policy in recent years has prescribed the role, function and form for services in England. Evidence of their effectiveness post-policy implementation has been limited to date and minimal guidance has been available on how services should operate together as whole systems. This paper reports findings from a study of referrals and their outcomes in respect of specialist community mental health services following implementation of national policy and its interpretation and configuration at a local level. Findings highlight that gateway workers configured as a team operating between primary and secondary care can effectively shield community mental health teams from high numbers of referrals that they would deem inappropriate. The study also identified the triage role of this service as being crucial to the effectiveness of developing and maintaining care pathways and also in potentially supporting the mental health capability of primary care.


Sujet(s)
Services communautaires en santé mentale/organisation et administration , Réforme des soins de santé/organisation et administration , Soins de santé primaires/organisation et administration , Orientation vers un spécialiste/organisation et administration , Médecine d'État/organisation et administration , Adolescent , Adulte , Sujet âgé , Programme clinique/organisation et administration , Angleterre/épidémiologie , Femelle , Politique de santé , Recherche sur les services de santé , Humains , Mâle , Troubles mentaux/diagnostic , Troubles mentaux/épidémiologie , Troubles mentaux/thérapie , Adulte d'âge moyen , Évaluation des besoins/organisation et administration , , Évaluation de programme , Facteurs de risque , Enquêtes et questionnaires , Triage/organisation et administration
2.
Neurobiol Aging ; 24(4): 597-606, 2003.
Article de Anglais | MEDLINE | ID: mdl-12714117

RÉSUMÉ

Physical activity appears to attenuate the decline of cognitive function typically observed in older men and women. The P300 component of the event-related potential (ERP) is particularly affected by aging and allows for basic neurobiological assessment of cognitive function. Three aspects of the P300 component (i.e. latency, amplitude, and area under the curve (AUC)), elicited by an oddball task, were derived to assess cognitive function in young and older participants (N=73) who were further classified as high- and low-active. The low-active elderly participants exhibited larger AUC values than those observed in all other groups which were undifferentiated. That is, the high-active elderly and the young participants exhibited smaller AUC values than the low-active older group. In conclusion, higher levels of physical activity in the elderly may be associated with a reduction in the neural resources allocated in response to simple cognitive challenge. This interpretation is consistent with the concept of psychomotor efficiency proposed by Hatfield and Hillman [The psychophysiology of sport: a mechanistic understanding of the psychology of superior performance. In: Singer RN, Hausenbias HA, Janelle CM, editors. Handbook of sport psychology. 2nd ed. New York: Wiley; 2001, p. 362-88].


Sujet(s)
Vieillissement/physiologie , Cognition/physiologie , Potentiels évoqués cognitifs P300/physiologie , Exercice physique/physiologie , Adulte , Sujet âgé , Analyse de variance , Aire sous la courbe , Humains , Mâle , Adulte d'âge moyen , Activité motrice/physiologie
3.
Biol Psychol ; 58(3): 263-77, 2001 Dec.
Article de Anglais | MEDLINE | ID: mdl-11698117

RÉSUMÉ

A number of investigators have reported elevated left temporal alpha power in marksmen during response preparation. This finding has been interpreted to indicate the suppression of irrelevant cognitive processes. However, lower-order motor processes have not been excluded as a possible explanation. Event-related alpha power (11-13 Hz) was examined at sites T3, T4, C3, and C4 in eight skilled marksmen during shooting and two control tasks varying in perceptual-motor complexity. Over an 8-s period preceding the trigger pull, the marksmen exhibited higher power and slope at T3 than at all other sites during shooting compared with the control conditions. No such difference between conditions was detected at C3 and C4. The relative synchrony of left temporal alpha power during shooting, in conjunction with the lack of change at central sites, is inconsistent with the explanation that the effect is accounted for by 'lower-order' motor processes exclusively involving the central region.


Sujet(s)
Cognition , Aptitudes motrices , Lobe temporal/physiologie , Adulte , Potentiels évoqués/physiologie , Armes à feu , Humains , Mâle , Processus mentaux
4.
Soc Psychiatry Psychiatr Epidemiol ; 36(5): 260-6, 2001 May.
Article de Anglais | MEDLINE | ID: mdl-11515705

RÉSUMÉ

BACKGROUND: Supervised Discharge Orders (SDOs) were introduced in 1995, as an amendment to the Mental Health Act in England and Wales. They require patients to abide by specific conditions on discharge from hospital, but can not enforce medication compliance. On introduction, SDOs were received with scepticism by the psychiatric profession. The purpose of this study was to describe the use of SDOs in England and the characteristics of patients made subject to these orders, and to evaluate the effectiveness of the order in securing treatment compliance on discharge from hospital. METHOD: A survey was conducted of 170 mental health provider Trusts in England. Interviews with senior managers in 12 Trusts and associated Local Authorities were subjected to qualitative analysis, and a cohort of patients subject to SDOs in 56 randomly sampled Trusts was described. RESULTS: SDOs were being used for 596 patients (1.2 per 100,000 total population) at the survey date in 1999, and use had been increasing steadily since its introduction. The order is not systematically considered for all potential cases. The majority of the 182 patients in the cohort had complied, if sometimes intermittently, with conditions of the order. CONCLUSIONS: For patients compliant with SDOs, the pressures necessary to treat effectively need not involve powers to enforce medication compliance.


Sujet(s)
Prise en charge personnalisée du patient , Législation médicale , Troubles mentaux/traitement médicamenteux , Observance par le patient/statistiques et données numériques , Sortie du patient/législation et jurisprudence , Adulte , Neuroleptiques/usage thérapeutique , Études de cohortes , Angleterre , Femelle , Humains , Mâle , Troubles mentaux/rééducation et réadaptation , Adulte d'âge moyen , , Patients en consultation externe/législation et jurisprudence , Observance par le patient/psychologie , Enquêtes et questionnaires
5.
Soc Psychiatry Psychiatr Epidemiol ; 36(10): 508-15, 2001 Oct.
Article de Anglais | MEDLINE | ID: mdl-11768849

RÉSUMÉ

BACKGROUND: Two measures in the English Mental Health Act allow requirements to be imposed upon patients living in the community. These are Guardianship (Section 7) and Supervised Discharge (Section 25A). AIMS: The paper aims to compare patients with mental illnesses, made subject to Guardianship or Supervised Discharge. METHOD: Data on patient characteristics, impairment, needs and interventions were collected from keyworkers in a random national sample of Trusts and local authorities. Ratings were obtained on standardised measures of disability, impairment and needs. RESULTS: Patients placed on Supervised Discharge were more likely to have problems of treatment compliance and drug misuse, whilst those on Guardianship were more likely to have problems of social welfare and higher ratings of disability and impairment. Supervised Discharge has a higher proportion of African-Caribbean patients. Interventions delivered are rated as effective for both measures. CONCLUSIONS: Legal changes proposed in England include a single power for supervision in the community. This should not mean a focus on risk management to the neglect of social welfare interventions.


Sujet(s)
Services communautaires en santé mentale/législation et jurisprudence , Désinstitutionnalisation/législation et jurisprudence , Tuteurs légaux , Sortie du patient/législation et jurisprudence , Personnes handicapées mentales/législation et jurisprudence , Adulte , Angleterre , Femelle , Humains , Mâle , Adulte d'âge moyen , Personnes handicapées mentales/rééducation et réadaptation , Gestion du risque/législation et jurisprudence , Organismes d'aide sociale/législation et jurisprudence
6.
Psychophysiology ; 37(6): 731-6, 2000 Nov.
Article de Anglais | MEDLINE | ID: mdl-11117453

RÉSUMÉ

Identification of the necessary stimulus properties to elicit the stimulus preceding negativity (SPN) has been the impetus for numerous research studies. The current study was conducted to explore the possibility that the SPN is an index of cognitive resource allocation. An auditory warning stimulus (S1) indicated whether an easy or difficult discrimination would occur at S2. The SPN was collected before a nonmotor discrimination task (S2) that consisted of identifying the higher of two bars. To eliminate the influence of motor processing prior to S2, a button press on the side of the higher bar was held until perception of a response cue (S3). Additionally, P3, contingent negative variation (CNV), and behavioral measures were collected to assist in assessing the SPN. Results indicated that although the SPN exhibited increased negativity, no differences were observed based on task difficulty. However, task difficulty did affect P3 data for both the warning tone and the discrimination task, an effect not observed for the CNV. Overall, the data did not support that hypothesis that the SPN provides an index of cognitive demand.


Sujet(s)
Attention/physiologie , Variation contingente négative/physiologie , Potentiels évoqués moteurs/physiologie , Reconnaissance visuelle des formes/physiologie , Discrimination de la hauteur tonale/physiologie , Temps de réaction/physiologie , Adolescent , Adulte , Cartographie cérébrale , Cortex cérébral/physiologie , Femelle , Humains , Mâle , Résolution de problème/physiologie , Performance psychomotrice/physiologie
7.
Biol Psychol ; 53(2-3): 131-60, 2000 Jul.
Article de Anglais | MEDLINE | ID: mdl-10967230

RÉSUMÉ

Log-transformed EEG power spectral estimates (6-7, 9,10-11,18-22, and 36-44 Hz), obtained from skilled marksmen and novice shooters at sites F3, F4, C3, C4,T3, T4, P3, P4, O1, and O2 during the aiming period (6 s) of a target shooting task for each of 40 trials up to the moment of trigger pull, were contrasted to determine regional differences in cortical activation. The EEG power obtained from both groups during the preparatory aiming period was also compared to that observed for a similar time period during the processing of standard verbal and spatial tasks. The marksmen exhibited less activation than the novice shooters at all sites during the aiming period with a pronounced difference in the left central-temporal-parietal area. Fewer group differences in cortical activation were observed during the comparative verbal and spatial tasks with which the groups held equal experience. Additionally, the novice shooters exhibited a cortical activation pattern during target shooting that was similar to that observed during the processing of the comparative verbal and spatial tasks. In contrast, marksmen generally exhibited less cortical activation during the aiming period when contrasted to that during the novel comparative tasks. These results are consistent with the notion of relative economy in the cortical processes of marksmen, relative to controls, during the specific challenge with which they are highly practiced.


Sujet(s)
Cognition/physiologie , Électroencéphalographie , Armes à feu , Lobe occipital/physiologie , Perception de l'espace/physiologie , Lobe temporal/physiologie , Perception visuelle/physiologie , Adulte , Femelle , Latéralité fonctionnelle/physiologie , Humains , Mâle
8.
Res Q Exerc Sport ; 71(2): 162-70, 2000 Jun.
Article de Anglais | MEDLINE | ID: mdl-10925813

RÉSUMÉ

Force and electromyographic (EMG) activity of the biceps and triceps brachii were measured in 15 strength-trained men during maximal isometric action of the forearm flexors, with the elbow at 90 degrees, following 20-s periods of psyching (PSY), reading aloud (RA), and mental arithmetic (MA). Perceived arousal and attentional focus ratings for PSY were greater than those obtained for RA and MA, which were undifferentiated. Perceived effort, biceps and triceps EMG, and maximal force did not differ across conditions. Therefore, in highly trained men under conditions of brief exertion, when the biomechanics of the muscular action were controlled, psyching resulted in a perception of enhanced readiness but did not influence force or muscular activation differently from psychological states that were preceded by distraction.


Sujet(s)
Exercice physique , Avant-bras , Contraction isométrique , Muscles/physiologie , Adulte , Éveil , Électromyographie , Humains , Mâle
9.
Med Sci Sports Exerc ; 32(3): 581-91, 2000 Mar.
Article de Anglais | MEDLINE | ID: mdl-10730999

RÉSUMÉ

PURPOSE: The aim of this study was to determine whether higher aerobic fitness is associated with enhanced vagal influences on the myocardium, resulting in moderation of chronotropic cardiac activity during psychological stress and recovery. METHOD: Heart period (HP) and respiratory sinus arrhythmia (RSA) were obtained from 10 aerobically trained (AT) and 10 untrained (UT) college-aged men at rest and during three contiguous psychological challenges and 3 min of recovery. Ratings of perceived stress were obtained at the end of the rest period, at the midpoint of each stressor, and at 30 s into recovery. Time series methods were used to quantify RSA from the beat-to-beat HP series. Responsivity was assessed both in terms of absolute levels of activity and phasic changes in activity (task or recovery minus baseline). RESULTS: Both groups reported similar levels of subjective stress throughout the experiment. The AT exhibited longer HP at rest and during psychological stress and recovery than did the UT. However, the groups did not differ on RSA at rest or during psychological stress and recovery, nor did they differ on phasic changes in RSA or HP during stress or recovery. Additionally, aerobic capacity was not correlated with absolute levels or phasic changes in RSA during psychological challenge for either group and, except in Min 2 for the UT, similar results were obtained for recovery. CONCLUSIONS: The results supported the hypothesis that, among young men, higher aerobic fitness is associated with longer HP at rest and during psychological stress and recovery. However, the lower cardiac chronotropic activation observed among the AT relative to the UT was not paralleled by a group difference in the amplitude of RSA. These results suggest that the group difference in HP was not mediated directly by the vagal mechanisms manifested in the amplitude of RSA.


Sujet(s)
Exercice physique/physiologie , Rythme cardiaque/physiologie , Aptitude physique , Stress psychologique/physiopathologie , Adulte , Facteurs âges , Tests de la fonction cardiaque , Humains , Mâle , Consommation d'oxygène , Nerf vague/physiologie
10.
Biol Psychol ; 52(1): 71-83, 2000 Feb.
Article de Anglais | MEDLINE | ID: mdl-10686373

RÉSUMÉ

Electroencephalographic (EEG) activity during the preshot period was investigated in seven skilled marksmen. Specifically, alpha and beta spectral power were obtained for the 4-s period prior to the execution or rejection of shots. Rejected shots were defined as those that resulted in the marksman's self-initiated decision to withdraw their rifle from the target rather than execute the shot. EEG activity during the preparatory period was contrasted between the executed and rejected shots to better understand the involved attentional processes associated with the preshot state. Results for rejected compared with executed shots revealed a progressive increase in alpha and beta power for rejected compared with executed shots, which increased across the preparatory period. Furthermore, increased spectral power was found in the left compared with the right hemisphere for both executed and rejected shots, and in the different regions of the scalp. Therefore, the decision to reject a shot seems to be characterized by inappropriate allocation of the neural resources associated with task execution.


Sujet(s)
Cortex cérébral/physiologie , Électroencéphalographie , Armes à feu , Sports/physiologie , Adulte , Rythme alpha , Attention/physiologie , Rythme bêta , Dominance cérébrale/physiologie , Femelle , Analyse de Fourier , Humains , Mâle , Traitement du signal assisté par ordinateur
11.
Ethn Dis ; 9(1): 104-10, 1999.
Article de Anglais | MEDLINE | ID: mdl-10355479

RÉSUMÉ

Exaggerated blood pressure reactivity to behavioral stress has been observed in the African-American population, and such a pressor response is believed to play a role in hypertension. Regular aerobic exercise has been shown to exert an anti-hypertensive effect, and this may alter the blood pressure hyperreactivity observed in African Americans. To test the hypothesis that aerobic exercise attenuates pressor reactivity in African Americans, we studied eight healthy aerobically-trained normotensive African-American females and five similar sedentary females. The stress stimuli consisted of the cold pressor test with the foot immersed in ice water for two minutes. The aerobic exercise training protocol consisted of six weeks of jogging at 60-70% of peak oxygen uptake (VO2peak), three days/week for 35 min/exercise session. Systolic blood pressure, diastolic blood pressure, mean arterial blood pressure, heart rate, cardiac output, total peripheral resistance, and forearm blood flow were measured. Manifestation of a training effect was illustrated by a 24.1 +/- 0.2% increase in VO2peak (26.9 +/- 1.2 mL x kg(-1) min(-1) vs 35.4 +/- 1.6 mL x kg(-1) min(-1)) (P<.05). Within the exercise-trained group there was a 6.3 +/- .15% decrease in systolic pressure (129 +/- 4.6 mm Hg vs. 121 +/- 5.4 mm Hg) (P<.05), and a 5.0 +/- .05% decrement in mean arterial blood pressure (99 +/- 3.3 mm Hg vs 94 +/- 3.6 mm Hg) (P<.05) during the cold pressor test. Pressor reactivity to cold stress did not change in the untrained group. Measures of heart rate, cardiac output, total peripheral resistance, and forearm blood flow were unaltered during conditions of the cold pressor test. We conclude that aerobic exercise attenuates the blood pressure reactivity to behavioral stress in young, adult normotensive African-American females. A lifestyle change such as exercising may play a role in reducing the risk of hypertension in African-American women.


Sujet(s)
, Pression sanguine/physiologie , Basse température/effets indésirables , Épreuve d'effort , Traitement par les exercices physiques/méthodes , Hypertension artérielle/prévention et contrôle , Hypertension artérielle/physiopathologie , Adulte , Femelle , Rythme cardiaque/physiologie , Humains , Hypertension artérielle/diagnostic , Hypertension artérielle/génétique , Mode de vie , Consommation d'oxygène/physiologie , Résistance vasculaire/physiologie
12.
Med Sci Sports Exerc ; 30(2): 206-14, 1998 Feb.
Article de Anglais | MEDLINE | ID: mdl-9502347

RÉSUMÉ

Respiratory sinus arrhythmia (RSA) was examined in aerobically trained (AT) and untrained (NT) college-aged males during 12 periods consisting of a 3-min sitting baseline, six common 3-min absolute exercise stages, and five 3-min recovery stages that followed voluntary exhaustion to determine the relationship of work and training status to parasympathetic influence upon the heart. RSA systematically decreased during absolute exercise, was observed at heart rates (HR) above 100 beats x min(-1), and progressively increased during recovery. Additionally, independent of work stages, comparative regression analyses were conducted for both the exercise and recovery phases, separately, in which HR was regressed on RSA, as well as RSA on % VO2max, to contrast the obtained relationships for the AT and NT. No differences were revealed as a function of endurance training status as the slopes and intercepts obtained for the two groups from each of these analyses were similar. The within-subject correlations between RSA and % VO2max, calculated for each of the individuals across all 12 periods, were consistently negative. Between-subjects correlations of RSA with RR and tidal volume were predominantly nonsignificant, indicating that RSA, as measured here, is independent of individual differences in ventilatory activity and, as such, can be compared between groups during exercise. The findings demonstrate that RSA is detectable during both exercise and recovery, even at HR beyond 100 beats x min(-1), and reveals a similar relationship to HR and metabolic state in both aerobically trained and untrained populations.


Sujet(s)
Arythmie sinusale/physiopathologie , Exercice physique/physiologie , Éducation physique et entraînement physique , Respiration/physiologie , Nerf vague/physiologie , Adulte , Rythme cardiaque/physiologie , Humains , Mâle , Consommation d'oxygène/physiologie , Aptitude physique/physiologie , Analyse de régression
15.
J Adolesc ; 19(2): 127-39, 1996 Apr.
Article de Anglais | MEDLINE | ID: mdl-9245271

RÉSUMÉ

Seventy-two members of staff working in children's residential units in a Local Authority were surveyed, to elicit their experiences and evaluations of working with child mental health professionals. Whilst the majority of staff held few or no formal educational qualifications, they emerged as an experienced group, with a level of confidence in their knowledge and skill base. Support was identified as coming predominantly from within units themselves; relatively few staff had direct contact with child psychiatrists or psychologists, although many children received a service. Staff in general felt that child mental health services were not helpful to them in terms of their work with young people. However, the majority of staff indicated a need for greater direct involvement across a range of child behavioural and emotional problems. The findings are discussed in terms of the changing population of "looked after" children and the recommendations of the Warner Report.

16.
Am J Cardiol ; 75(5): 360-4, 1995 Feb 15.
Article de Anglais | MEDLINE | ID: mdl-7856528

RÉSUMÉ

Although beta blockers have demonstrated a salutary effect on ventricular function in patients with heart failure, it is unclear whether a nonselective third-generation beta blocker produces different hemodynamic and energetic effects than a second-generation beta 1 selective agent. In 30 male patients with heart failure, we retrospectively analyzed hemodynamic data from 2 protocols examining the effects of a nonselective beta antagonist bucindolol (n = 15), and a highly selective beta 1 antagonist metoprolol (n = 15). Both studies were conducted in a similar fashion with patients undergoing cardiac catheterization before and after receiving 3 months of beta blockade. Both groups were matched at baseline in terms of ventricular function. beta blockade resulted in similar reductions in heart rate and similar improvements in ejection fraction, ventricular volumes, stroke and minute work, peak +dP/dt, and isovolumic relaxation in both groups. Only patients taking bucindolol had a significant within-group decrease in resting left ventricular end-diastolic pressure. The metoprolol group had a greater decrease in coronary sinus blood flow and myocardial oxygen consumption. Bucindolol increased cardiac index more than metoprolol, but did not increase stroke volume index more than metoprolol. The bucindolol group had an increase in systolic elastance, whereas the metoprolol group had a parallel left shift in this relation. Thus, metoprolol reduces coronary blood flow and myocardial oxygen consumption more than bucindolol, whereas bucindolol produces slightly more favorable improvements in resting cardiac index and end-diastolic pressure. Otherwise, these 2 agents produced similar hemodynamic changes.


Sujet(s)
Antagonistes bêta-adrénergiques/usage thérapeutique , Défaillance cardiaque/traitement médicamenteux , Métoprolol/usage thérapeutique , Propanolamines/usage thérapeutique , Antagonistes bêta-adrénergiques/pharmacologie , Adulte , Méthode en double aveugle , Défaillance cardiaque/physiopathologie , Hémodynamique/effets des médicaments et des substances chimiques , Humains , Mâle , Métoprolol/pharmacologie , Propanolamines/pharmacologie , Études rétrospectives , Fonction ventriculaire gauche/effets des médicaments et des substances chimiques
17.
J Am Coll Cardiol ; 25(1): 154-62, 1995 Jan.
Article de Anglais | MEDLINE | ID: mdl-7798494

RÉSUMÉ

OBJECTIVES: The aim of this study was to determine which patients will have systolic and diastolic improvement after beta-blockade with metoprolol. BACKGROUND: Beta-adrenergic blocking agents improve systolic and diastolic function in patients with heart failure. However, it is unclear which patients will respond best to therapy. METHODS: We retrospectively examined baseline characteristics of 24 patients who underwent double-blind then open-label treatment with metoprolol to determine which characteristic predicted improvement in systolic and diastolic function. Degree of improvement in systolic function (22 patients) was defined by the change in left ventricular ejection fraction after 3 months of therapy. Degree of improvement in diastolic function (15 patients) was defined as the change in left ventricular end-diastolic pressure and change in the slope of the isovolumetric relaxation rate-end-systolic pressure relation. RESULTS: Both systolic blood pressure at baseline (r = 0.54, p = 0.009) and the maximal positive value of the first derivative of left ventricular pressure with respect to time (peak +dP/dt) at baseline (r = 0.39, p = 0.07) correlated with improvement in ejection fraction after metoprolol treatment. Stepwise logistic regression demonstrated that only peak systolic pressure was an independent predictor of systolic improvement. Baseline heart rate, ventricular volumes, ejection fraction and adrenergic activation, as reflected by coronary sinus norepinephrine, did not predict response. Patients with the most diastolic impairment at baseline had the most favorable diastolic improvement. Those with the lowest myocardial respiratory quotient (most fatty acid utilization) at baseline also had the most marked reduction in left ventricular end-diastolic pressure. CONCLUSIONS: These data suggest that those patients with the highest peak systolic pressure, highest left ventricular end-diastolic pressure and most prolonged isovolumetric relaxation at baseline will respond best to therapy with metoprolol. However, other patients without these characteristics may also benefit.


Sujet(s)
Cardiomyopathie dilatée/traitement médicamenteux , Cardiomyopathie dilatée/physiopathologie , Métoprolol/usage thérapeutique , Contraction myocardique/effets des médicaments et des substances chimiques , Adulte , Sujet âgé , Cardiomyopathie dilatée/imagerie diagnostique , Diastole/effets des médicaments et des substances chimiques , Méthode en double aveugle , Coeur/imagerie diagnostique , Coeur/physiopathologie , Hémodynamique/effets des médicaments et des substances chimiques , Humains , Mâle , Adulte d'âge moyen , Pronostic , Études prospectives , Scintigraphie , Études rétrospectives , Systole/effets des médicaments et des substances chimiques
18.
J Am Coll Cardiol ; 24(5): 1310-20, 1994 Nov 01.
Article de Anglais | MEDLINE | ID: mdl-7930255

RÉSUMÉ

OBJECTIVES: This study examined the effects of metoprolol on left ventricular performance, efficiency, neurohormonal activation and myocardial respiratory quotient in patients with dilated cardiomyopathy. BACKGROUND: The mechanism by which beta-adrenergic blockade improves ejection fraction in patients with dilated cardiomyopathy remains an enigma. Thus, we undertook an extensive hemodynamic evaluation of this mechanism. In addition, because animal models have shown that catecholamine exposure may increase relative fatty acid utilization, we hypothesized that antagonism of sympathetic stimulation may result in increased carbohydrate utilization. METHODS: This was a randomized, double-blind, prospective trial in which 24 men with nonischemic dilated cardiomyopathy underwent cardiac catheterization before and after 3 months of therapy with metoprolol (n = 15) or placebo (n = 9) in addition to standard therapy. Pressure-volume relations were examined using a micromanometer catheter and digital ventriculography. RESULTS: At baseline, the placebo-treated patients had somewhat more advanced left ventricular dysfunction. Ejection fraction and left ventricular performance improved only in the metoprolol-treated patients. Stroke and minute work increased without an increase in myocardial oxygen consumption, suggesting increased myocardial efficiency. Further increases in ejection fraction were seen between 3 and 6 months in the metoprolol group. The placebo group had a significant increase in ejection fraction only after crossover to metoprolol. A significant relation between the change in coronary sinus norepinephrine and myocardial respiratory quotient was seen, suggesting a possible effect of adrenergic deactivation on substrate utilization. CONCLUSIONS: These data demonstrate that in patients with cardiomyopathy, metoprolol treatment improves myocardial performance and energetics, and favorably alters substrate utilization. Beta-adrenergic blocking agents, such as metoprolol, are hemodynamically and energetically beneficial in the treatment of myocardial failure.


Sujet(s)
Cardiomyopathie dilatée/traitement médicamenteux , Métoprolol/usage thérapeutique , Cathétérisme cardiaque , Cardiomyopathie dilatée/imagerie diagnostique , Cardiomyopathie dilatée/physiopathologie , Études croisées , Méthode en double aveugle , Métabolisme énergétique/effets des médicaments et des substances chimiques , Études de suivi , Humains , Mâle , Adulte d'âge moyen , Myocarde/métabolisme , Norépinéphrine/métabolisme , Consommation d'oxygène/effets des médicaments et des substances chimiques , Études prospectives , Ventriculographie isotopique , Débit systolique/effets des médicaments et des substances chimiques , Facteurs temps , Fonction ventriculaire gauche/effets des médicaments et des substances chimiques
20.
J Card Fail ; 1(1): 45-56, 1994 Oct.
Article de Anglais | MEDLINE | ID: mdl-9420632

RÉSUMÉ

The factors that determine left ventricular end-diastolic pressure (LVEDP) are not completely understood. While many investigators measure relaxation in patients with heart failure, its relative functional importance remains unclear. The authors studied 22 patients with cardiomyopathy before and after 3 months of therapy with metoprolol or placebo. At catheterization, LVEDP, isovolumic relaxation rates not normalized for load (tau), the slope of the tau-end-systolic pressure relation (R), the constant of chamber stiffness (k), left ventricular ejection fraction, stroke volume, and coronary sinus norepinephrine levels were measured using micromanometer pressure measurements and digital ventriculography. The myocardial respiratory quotient was measured using blood gas analysis of the coronary sinus and left ventricular blood. Univariate analysis demonstrated that changes in LVEDP correlated with changes in relaxation rates, R, and the myocardial respiratory quotient. However, multivariate stepwise regression analysis demonstrated that only changes in R independently correlated with changes in LVEDP. These data suggest that relaxation may play some role in the determination of LVEDP in patients with heart failure. Changes in glycolytic activity may also play a role in the determination of LVEDP in patients with congestive heart failure.


Sujet(s)
Défaillance cardiaque/physiopathologie , Fonction ventriculaire gauche/physiologie , Pression ventriculaire , Adulte , Glycolyse , Humains , Mâle , Adulte d'âge moyen
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