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1.
Circulation ; 102(6): 636-41, 2000 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-10931803

RESUMO

BACKGROUND: Inflammation is an important component of ischemic heart disease. PTX3 is a long pentraxin whose expression is induced by cytokines in endothelial cells, mononuclear phagocytes, and myocardium. The possibility that PTX3 is altered in patients with acute myocardial infarction (AMI) has not yet been tested. METHODS AND RESULTS: Blood samples were collected from 37 patients admitted to the coronary care unit (CCU) with symptoms of AMI. PTX3 plasma concentrations, as measured by ELISA, higher than the mean+2 SD of age-matched controls (2.01 ng/mL) were found in 27 patients within the first 24 hours of CCU admission. PTX3 peaked at 7.5 hours after CCU admission, and mean peak concentration was 6.94+/-11.26 ng/mL. Plasma concentrations of PTX3 returned to normal in all but 3 patients at hospital discharge and were unrelated to AMI site or extent, Killip class at entry, hours from symptom onset, and thrombolysis. C-reactive protein peaked in plasma at 24 hours after CCU admission, much later than PTX3 (P<0.001). Patients >64 years old and women had significantly higher PTX3 concentrations at 24 hours (P<0.05). PTX3 was detected by immunohistochemistry in normal but not in necrotic myocytes. CONCLUSIONS: PTX3 is present in the intact myocardium, increases in the blood of patients with AMI, and disappears from damaged myocytes. We suggest that PTX3 is an early indicator of myocyte irreversible injury in ischemic cardiomyopathy.


Assuntos
Proteína C-Reativa/metabolismo , Infarto do Miocárdio/metabolismo , Componente Amiloide P Sérico/metabolismo , Idoso , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Infarto do Miocárdio/patologia , Miocárdio/metabolismo , Miocárdio/patologia , Necrose , Concentração Osmolar , Valores de Referência , Fatores de Tempo
2.
Am Heart J ; 139(3): 511-21, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10689267

RESUMO

BACKGROUND: Cardiac sympathetic activation is one of the major and earlier changes observed in patients with heart failure. Its relation to the severity of the disease and its independent prognostic value show that it may directly contribute to the progression of heart failure. beta-Blockers are the most effective tool to counteract the untoward effects of sympathetic activation on the cardiovascular system. METHODS AND RESULTS: We reviewed the results of the placebo-controlled, double-blind studies about the effects of beta-blockers in patients with heart failure. These studies have involved almost 10,000 patients to date and have consistently shown that the long-term administration of beta-blockers is associated with a highly significant improvement in both left ventricular function and prognosis of the patients with heart failure. The evidence supporting the use of beta-blockers now equals or even surpasses that of angiotensin-converting enzyme inhibitors; therefore beta-blockers should be considered part of standard therapy. Issues that remain unclarified include the mechanisms through which beta-blockers may improve cardiac function and their tolerability and efficacy in specific groups of patients (such as those with asymptomatic left ventricular dysfunction, severe heart failure, the elderly, or those with left ventricular diastolic dysfunction). It is not currently clear whether the pharmacologic differences between individual beta-blockers are clinically relevant. If they are, the potential for even greater benefit with certain agents exists. It is hoped that these issues will be clarified by the results of ongoing multicenter trials.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Pressão Sanguínea/efeitos dos fármacos , Ensaios Clínicos como Assunto , Progressão da Doença , Método Duplo-Cego , Insuficiência Cardíaca/fisiopatologia , Frequência Cardíaca/efeitos dos fármacos , Humanos , Seleção de Pacientes , Transdução de Sinais/efeitos dos fármacos , Função Ventricular Esquerda/efeitos dos fármacos , Remodelação Ventricular/fisiologia
3.
J Cardiovasc Pharmacol ; 25(5): 732-40, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7630152

RESUMO

Ibopamine has hemodynamic and neurohumoral effects potentially useful for the treatment of congestive heart failure (CHF), but its mechanism of action is not completely clear. To evaluate the role of dopaminergic receptor stimulation in the hemodynamic and neurohumoral activity of ibopamine, we compared the effects of ibopamine, 100 mg orally (p.o.) with those of the dopamine 2, 4, and 6 micrograms/kg/min intravenously (i.v.) and of the DA2 agonist dihydroergotoxine 6 micrograms/kg i.v. in 13 patients with chronic CHF [left ventricular ejection fraction (LVEF) < or = 35%]. All patients underwent right heart Swan-Ganz catheterization with determination of hemodynamic parameters at baseline, after 30 min of infusion of each dose of dopamine (DA) and < or = 6 h after ibopamine and dihydroergotoxine administration. Blood samples for the assessment of plasma renin activity (PRA), aldosterone, norepinephrine (NE), and epinephrine (Epi) were also obtained. Ibopamine induced a peak 21% increase of cardiac index (CI) with a 23 and 25% increase in stroke volume (SV) and stroke work indexes (SWI), respectively, and an 18% reduction in systemic vascular resistance (SVR). Similar changes were observed after DA infused at the doses of 2 and 4 micrograms/kg/min, whereas with the dose of 6 micrograms/kg/min heart rate (HR) increased by 23% and SV index (SVI) did not change further. Dihydroergotoxine administration induced only a significant 9% decrease in mean arterial pressure (MAP), with a 13% reduction in SVR.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Desoxiepinefrina/análogos & derivados , Di-Hidroergotoxina/uso terapêutico , Agonistas de Dopamina/uso terapêutico , Dopamina/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Administração Oral , Idoso , Aldosterona/sangue , Análise de Variância , Pressão Sanguínea/efeitos dos fármacos , Desoxiepinefrina/administração & dosagem , Desoxiepinefrina/farmacologia , Desoxiepinefrina/uso terapêutico , Di-Hidroergotoxina/administração & dosagem , Di-Hidroergotoxina/farmacologia , Dopamina/administração & dosagem , Dopamina/farmacologia , Agonistas de Dopamina/administração & dosagem , Agonistas de Dopamina/farmacologia , Epinefrina/sangue , Insuficiência Cardíaca/diagnóstico por imagem , Frequência Cardíaca/efeitos dos fármacos , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Norepinefrina/sangue , Cintilografia , Renina/sangue , Volume Sistólico/efeitos dos fármacos , Resistência Vascular/efeitos dos fármacos
4.
Cardiologia ; 38(12 Suppl 1): 415-25, 1993 Dec.
Artigo em Italiano | MEDLINE | ID: mdl-8020044

RESUMO

The role of mental stress in ischemic heart disease is two-fold: as a risk factor of coronary artery disease and as a trigger of acute ischemic attacks in patients with established coronary atherosclerosis. The role of stress as a risk factor is still controversial. Data regarding the relationship between occupational factors and development of coronary atherosclerosis have not been confirmed. A type personality, above all when anger and hostility traits are present, seems to be a predisposing factor for the development of coronary artery disease. These data however, were not confirmed in study groups including patients with a higher prevalence of other, more important, risk factors. Stress can have an important role as a trigger of acute ischemic attacks. This is indirectly shown by the circadian distribution of the main manifestations of ischemic heart disease (sudden death, myocardial infarct, ST segment depression). In fact, their incidence is significantly higher in the morning hours, after awakening, when mental stress is higher. In the laboratory setting, mental stress can induce myocardial ischemia in a variable percentage of patients (0 to 80%). Prevalence of mental stress-induced myocardial ischemia varies depending on the stressor used, the patients group and, above all, the diagnostic tool. Ischemic episodes induced by mental stress, in fact, are generally silent and less severe and extensive than those elicited by exercise stress testing. It is therefore often necessary to use methods, such as myocardial scintigraphy, with higher sensitivity for the detection of myocardial ischemia in comparison with ECG. Patients with mental stress-induced myocardial ischemia tend to present higher scores on measures of aggressivity, anger and hostility. These psychological features are related to a hightened cardiovascular reactivity with a brisk and greater increase in heart rate and blood pressure after exposure to stress. It would be therefore useful to identify patients with such a behaviour by psychological assessment and/or analysis of sympatho-vagal balance by analysis of heart rate variability. The mechanism by which mental stress can induce myocardial ischemia is represented by an increase in myocardial oxygen demand, through the increased heart rate and blood pressure, probably associated with an increase in coronary vascular resistance. This last phenomenon is likely caused by small coronary vessel constriction mediated by alpha-adrenergic activation and by a reduced EDRF release by the damaged endothelium.


Assuntos
Isquemia Miocárdica/etiologia , Estresse Fisiológico , Doença Aguda , Sistema Nervoso Autônomo/fisiopatologia , Doença Crônica , Circulação Coronária/fisiologia , Humanos , Incidência , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/epidemiologia , Isquemia Miocárdica/fisiopatologia , Isquemia Miocárdica/psicologia , Exposição Ocupacional , Personalidade , Estresse Fisiológico/fisiopatologia
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