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1.
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Changes in central hemodynamics as recorded by tetrapolar rheography were investigated in 90 coronary heart disease (CHD) patients with circulatory insufficiency (CI) receiving methiopril. Relevant clinical response was registered in 94%, hemodynamic in 83% of patients. Those with CI stage IIA and IIB benefited more. Arterial pressure went down significantly only in CHD patients with arterial hypertension. Tachycardia patients showed a reduction in pulse rate absent in bradycardia. Cardiac output increased at the expense of low afterload. Efficient doses averaged 300 mg/day.  相似文献   

3.
Angiotensin converting enzyme (ACE) inhibitors have emerged as a significant advance in the treatment of heart failure; yet only a minority (i.e., 30% to 40%) of eligible patients are being treated with these drugs, and even among treated patients, the doses used in clinical practice are substantially lower than those used in the clinical trials that established the efficacy and safety of these agents. The preference for low doses is based on the belief that low and high doses exert similar benefits but that high doses produce more side effects. Yet, most studies indicate that large doses of ACE inhibitors produce greater hemodynamic and clinical effects than small doses, with no additional toxicity. However, it is uncertain whether the survival effects of these drugs are also related to dose. To address this question, a large multinational, double-blind clinical trial (Assessment of Treatment With Lisinopril and Survival [ATLAS]) was launched to compare the effects of low and high doses of the ACE inhibitor lisinopril on the survival of patients with heart failure. If the study demonstrates that large doses are needed to produce optimal effects on mortality, then the low dose strategies that are now widely used in clinical practice may be inadvertently nullifying the enormous potential benefits that ACE inhibitors might otherwise have on public health.  相似文献   

4.
Cyclooxygenase inhibitors may affect the hemodynamic status of patients with heart failure adversely and may also block the vasodilatory effects of angiotensin-converting enzyme (ACE) inhibitors in such patients. Relatively low doses of the cyclooxygenase inhibitor acetylsalicylic acid (ASA) are now used routinely in ischemic heart disease, the most important cause of heart failure. Therefore, we investigated the hemodynamic interaction between ASA and captopril in heart failure. In a randomized, cross-over study, 13 patients with congestive heart failure (CHF) who were already receiving maintenance treatment with an ACE inhibitor received a single dose of 25 mg captopril combined with 236 mg ASA or placebo. Peripheral blood flow was studied noninvasively by venous occlusion plethysmography of the calves. Liver blood flow was estimated from indocyanine green (ICG) clearance. Administration of captopril alone significantly decreased blood pressure (BP), and ICG clearance. Calf blood flow remained unchanged. However, after arterial occlusion, hyperemic calf blood flow persisted for longer. Captopril alone did not significantly change the plasma levels of the vasodilating prostaglandins PGI2 and PGE2 or the vasoconstricting thromboxane A2 (TXA2). In contrast, captopril combined with ASA reduced the plasma levels of these vasoactive substances, with significant decreases in PGE2 and TXA2 as compared with captopril alone, yet the hemodynamic alterations after captopril plus ASA were similar to those observed after captopril alone. A single antithrombotic dose of ASA (236 mg) in 13 patients with CHF [New York Heart Association (NYHA) class II-IV] undergoing chronic treatment with ACE inhibitors had no discernible effect on hemodynamic status.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

5.
Nitric oxide (NO) plays a role in controlling vascular tone and regulates the contractile properties of cardiac myocytes. Patients with heart failure exhibit high plasma levels of nitrite/nitrate (NOx), a stable metabolite of NO, and of cytokines such as tumor necrosis factor-alpha, a potent inducer of NO synthase. An increase in inducible NO synthase activity has been found in cardiac tissue from patients with dilated cardiomyopathy. These findings raise the possibility that local or systemic overproduction of NO induced by cytokines exerts a chronic negative inotropic effect on the myocardium and may have detrimental effects on systemic hemodynamics in patients with heart failure. Plasma levels of NG,NG-dimethylarginine (asymmetric dimethylarginine; ADMA), a circulating endogenous NO synthase inhibitor, were measured in control subjects and patients with valvular, hypertensive, or ischemic heart diseases or idiopathic cardiomyopathy. The plasma levels of NOx and ADMA were assessed by high performance liquid chromatography. The plasma levels of NOx and ADMA were significantly elevated in patients with heart failure. Both NOx and ADMA were positively correlated with New York Heart Association functional class. There was a significant inverse correlation between plasma NOx and ejection fraction, as estimated by echocardiography. A significant relationship between plasma NOx and ADMA was found only in patients with moderate to severe heart failure (r=0.41, p=0.01). Findings suggest a compensatory role of a circulating endogenous NO synthase inhibitor against induced NO synthase activity in patients with heart failure.  相似文献   

6.
BACKGROUND: Evidence from clinical trials in the past decade has consistently shown that angiotensin-converting enzyme (ACE) inhibitors reduce morbidity and mortality in patients with congestive heart failure (CHF). The extent to which clinical practice has adopted ACE inhibitor therapy is unknown. METHODS: The Cardiovascular Health Study is a prospective observational study of 5201 community-dwelling adults aged 65 years and older. Prevalent CHF cases were identified on study entry (from June 10, 1989, through May 31, 1990) and incident CHF cases were identified throughout 5 years of follow-up. Medication data were collected from annual medication inventories. The percentage of patients with CHF using ACE inhibitors was calculated at each annual examination. Temporal trends in CHF treatment with ACE inhibitors between June 10, 1989, through May 31, 1990, and June 1, 1994, through May 31, 1995, were analyzed. RESULTS: Use of ACE inhibitors to treat CHF increased slightly over time among prevalent cases at each annual examination: 26% of prevalent CHF cases were treated in 1989-1990 compared with 36% of prevalent cases in 1994-1995. This 10% increase was statistically significant (P<.01). Participants with low ejection fractions were 2 times more likely to be treated with ACE inhibitors than were those with normal ejection fraction and this tendency did not change over time. Among cases newly diagnosed in the year before the 1990-1991 examination, 42% were using ACE inhibitors; among those newly diagnosed in the year before 1994-1995, 40% were using ACE inhibitors. This 2% decrease was not statistically significant (P=.68). CONCLUSION: These findings suggest that, while the medical management of CHF with ACE inhibitors has increased modestly over time in prevalent cases, these drugs may still be underused, especially among incident cases.  相似文献   

7.
In addition to effects on survival, hemodynamics, and exercise capacity, quality of life has become an important outcome of therapy for chronic heart failure. A large clinical trial of the angiotensin-converting enzyme (ACE) inhibitor enalapril reports that certain domains of health-related quality of life (HRQL) have a long-term impact on survival in patients with reduced left ventricular systolic function, regardless of symptoms of heart failure at diagnosis. Results of large-scale clinical trials that measured the impact of several different ACE inhibitors on quality of life in these patients suggest benefits of the drugs, but data are confounded by a definite placebo effect. Studies are further confounded by high noncompletion rates for sicker patients, particularly beyond 1 year. Because measurement tools varied and different quality of life domains were evaluated, direct comparison of studies is problematic. Typically, HRQL measurements in patients receiving ACE inhibitors showed small improvement or did not differ significantly from those in placebo-treated patients with long-term follow-up, although short-term trials (< 6 mo) showed some benefit. Moreover, multicenter trials such as SOLVD, V-HeFT II, and ramipril studies indicated that ACE inhibitors do not compromise and may actually improve certain components of quality of life in a large number of patients with chronic heart failure secondary to reduced left ventricular systolic function while having favorable effects on survival, exercise capacity, hemodynamics, or symptoms.  相似文献   

8.
In patients with congestive heart failure (CHF) receiving therapy with angiotensin-converting enzyme (ACE) inhibition, institution of calcium channel antagonism with amlodipine provided favorable effects. The goal of the present study was to define potential mechanisms for these effects by measuring left ventricular function, hemodynamics, and neurohormonal system activity in a model of CHF in which amlodipine treatment had been instituted either as a monotherapy or in combination with ACE inhibition. Thirty-two pigs were instrumented to allow measurement of cardiac index, total systemic resistance index, and neurohormonal activity in the conscious state and assigned to one of four groups: (1) rapid atrial pacing (240 bpm) for 3 weeks (n = 8), (2) amlodipine (1.5 mg x kg(-1) x d[-1]) and pacing (n = 8), (3) ACE inhibition (fosinopril 1.0 mg/kg BID) and pacing (n = 8), and (4) amlodipine and ACE inhibition (1.0 mg x kg(-1) x d(-1) and 1.0 mg/kg BID, respectively) and pacing (n = 8). Measurements were obtained in the normal control state and after the completion of the treatment protocols. With rapid pacing, basal resting cardiac index was reduced compared with control values (2.7+/-0.2 versus 4.7+/-0.1 L x min(-1) x m(-2), respectively, P<.05) and increased from rapid pacing-only values with either amlodipine or combination therapy (3.7+/-0.3 and 4.4+/-0.5 L x min(-1) x m(-2), respectively, P<.05). Basal resting total systemic resistance index was higher in the rapid pacing-only group compared with control values (2731+/-263 versus 1721+/-53 dyne x s x cm(-5) x m2, respectively, P<.05), was reduced with either amlodipine treatment or ACE inhibition (2125+/-226 and 2379+/-222 dyne x s x cm(-5) x m2, respectively, P<.05), and was normalized with combination therapy. Plasma catecholamines, renin activity, and endothelin levels were increased threefold with rapid pacing. Amlodipine, either as a monotherapy or in combination with ACE inhibition, did not result in increased plasma catecholamines and renin activity compared with the rapid pacing-only group. Furthermore, combination therapy reduced steady state norepinephrine and normalized epinephrine levels. The results of the present study demonstrated that monotherapy with either amlodipine or ACE inhibition provides beneficial effects in this pacing model of CHF. Combined amlodipine and ACE inhibition provided greater benefit with respect to vascular resistance properties and neurohormonal system activity compared with either monotherapy.  相似文献   

9.
We reviewed the records of 242 patients admitted over 1 year with heart failure and an ejection fraction < or = 45% to assess the use of angiotensin-converting enzyme inhibitors. Most patients were treated with angiotensin-converting enzyme inhibitors. However, an important minority (8%) had no apparent reason for the lack of this treatment, highlighting the need for strategies to increase the use of these beneficial agents.  相似文献   

10.
11.
Methylated Digoxin preparation--beta-Methyldigoxin (Lanitop) was used in 50 patients with congestive heart failure of different etiology (tablets of 0.3--0.6 mG per day). Its employment proved very effective in the treatment of congestive heart failure. It is not contraindicated to patients with chronic coronary insufficiency with underlying athrosclerotic cardiosclerosis with signs of congestive circulatory insufficiency. Side-effects of beta-Methyldigoxin are mild and noted rather seldom.  相似文献   

12.
This study relates components of care, including patient characteristics, degree of initial morbidity, and process of care, to patient outcomes. One hundred twenty-two adults who were being treated for congestive heart failure by a sample of physicians in Fort Wayne, Indiana were studied. Data were obtained on the patients' personal characteristics; degree of illness at the beginning of the six-month study period; process measures (physician awareness, communication, medication use, therapeutic management, patient satisfaction, and utilization of services); and level of activity and symptoms at the end of the study period. These components were quantified and subjected to correlation and regression analysis. The largest and most significant predictors of outcome status were measures of initial disease status. Process variables were strongly and significantly associated with outcome only in a group of patients who were minimally symptomatic initially. The lack of an overall association between process of medical care and patient outcome cannot be generalized beyond these patients with congestive heart failure. A similar approach of dissection, quantification, and analysis of components of care, however, can be used to explore a possible relationship in other conditions and care delivery settings.  相似文献   

13.
BACKGROUND: Conventional approaches to management of congestive heart failure (CHF) rely on drugs that increase myocardial contractility or reduce ventricular afterload. These approaches often improve cardiac symptoms and survival, but may be associated with significant deleterious effects. An alternative approach is to enhance myocardial energy production. Dichloroacetate (DCA) stimulates pyruvate dehydrogenase activity and accelerates aerobic glucose, pyruvate, and lactate metabolism in myocardial cells. These alterations would be expected to improve myocardial function. HYPOTHESIS: The purpose of the investigation was to assess the efficacy of DCA in patients with left ventricular systolic dysfunction and to examine the mechanism by which improvement occurs. METHODS: A total of 25 patients (16 men, 9 women; age range 31-72 years, mean 59) with CHF and ejection fraction < or = 40% received an intravenous infusion of 50 mg/kg DCA over 15 min. Indices of systolic and diastolic function were obtained by two-dimensional and Doppler echocardiography performed at baseline, 30 min, and 60 min following completion of DCA infusion. RESULTS: Baseline ventricular ejection fraction was 27.3 +/- 9.1%; 17 patients (68%) had nonischemic cardiomyopathy. Heart rate increased after DCA infusion from 73.9 +/- 14.5 to 79.2 +/- 14.9 beats/min at 60 min; p = 0.02. Left ventricular diastolic and systolic volumes increased at 30 min compared with baseline (248.7 +/- 98.1 vs. 259.6 +/- 99.6; p = 0.04, and 180.1 +/- 80.4 vs. 192.2 +/- 84.9; p = 0.002, respectively), but stroke volume (49.2 +/- 19.1 vs. 48.9 +/- 18.1; p = 0.9) and ejection fraction (27.3 +/- 9.1 vs. 25.7 +/- 9.8; p = 0.2) were unchanged. Indices of diastolic function were also unchanged. CONCLUSION: Dichloroacetate infusion in patients with CHF is not associated with improvement in noninvasively assessed left ventricular function.  相似文献   

14.
OBJECTIVES: We sought to study the markers of lipid peroxidation and defenses against oxidative stress in patients with varying degrees of heart failure. BACKGROUND: Despite advances in other areas of cardiovascular disease, the morbidity and mortality from congestive heart failure (CHF) are increasing. Data mainly from animal models suggest that free radical injury may promote myocardial decompensation. However, there are no studies in humans correlating the severity of heart failure with increased free radical injury and antioxidants. METHODS: Fifty-eight patients with CHF and 19 control subjects were studied. In addition to complete clinical and echocardiographic evaluations, the prognosis of these patients was established by measuring the levels of soluble tumor necrosis factor-alpha receptors 1 and 2 (sTNF-R1 and sTNF-R2). Oxidative stress was evaluated by measuring plasma lipid peroxides (LPO), malondialdehyde (MDA), glutathione peroxidase (GSHPx) and vitamin E and C levels. RESULTS: The patients' age range, cause of heart failure and drug intake were comparable across the different classes of heart failure. Heart failure resulted in a significant increase in LPO (p < 0.005), MDA (p < 0.005), sTNF-R1 (p < 0.005) and sTNF-R2 (p < 0.005). There was a significant positive correlation between the clinical class of heart failure and LPO, MDA, sTNF-R1 and sTNF-R2 levels. There was an inverse correlation between GSHPx and LPO. With increased lipid peroxidation in patients with CHF, the levels of vitamin C decreased, but vitamin E levels were maintained. CONCLUSIONS: These data demonstrate a progressive increase in free radical injury and encroachment on antioxidant reserves with the evolution of heart failure; they also suggest that oxidative stress may be an important determinant of prognosis. The therapeutic benefit of administering antioxidant supplements to patients with CHF should be evaluated.  相似文献   

15.
To examine the efficacy of chronic amrinone therapy, the drug was administered to 12 patients with advanced congestive heart failure on average for 27.9 days. The majority of patients had a persistent increase in cardiac index and a persistent decrease in systemic vascular resistance. A decrease in pulmonary arterial diastolic pressure was observed after oral amrinone administration in three patients. However, changes in pulmonary arterial pressure were not consistent in response to intravenous administration of the drug. Thrombocytopenia occurred in four patients, hypogeusia was noted by three patients, and dysosmia developed in two patients. The cumulative survival of the amrinone patients was significantly poorer than that of a second group of patients with congestive heart failure having similar symptoms. These findings indicate that there is a subset of patients with congestive heart failure who do not benefit from chronic amrinone administration and that in such patients its use (especially when given concomitantly with potentially toxic and hypotensive drugs) should be extremely guarded.  相似文献   

16.
Amiodarone in low to moderate doses is generally safe in controlling arrhythmias in patients with congestive heart failure (CHF). However, its role is uncertain, because it did not affect the overall mortality rate in three out of four large-scale studies. Whether some subgroups might benefit is a matter of speculation. In patients with sustained ventricular tachycardia, or in those who have survived an episode of sudden death, implantation of a cardioverter-defibrillator may be a better strategy.  相似文献   

17.
In the biosynthesis of adrenomedullin (AM), an intermediate form, AM(1-52)-glycine-COOH (iAM), is cleaved from proAM and subsequently processed to a biologically active mature form, AM(1-52)-NH2 (mAM), by enzymatic amidation. We recently reported that immunoreactive AM in human plasma consists of mAM and iAM. To clarify the pathophysiological roles of mAM and iAM in heart failure, we established an assay method to specifically detect mAM, and we determined the plasma concentrations of mAM and iAM in 68 patients with congestive heart failure (CHF). The plasma mAM concentrations of the CHF patients classified as being class I or II of New York Heart Association (NYHA) functional classification were significantly greater than those of the 28 healthy controls, and a further increase was noted in the class III or IV patients. Similar increases in plasma iAM were also observed in these patients compared with controls. The increased plasma mAM and iAM in 12 patients with exacerbated CHF were significantly reduced by treatment of their CHF for 7 days. In addition, the plasma concentrations of both mAM and iAM were significantly correlated with pulmonary capillary wedge pressure, pulmonary artery pressure, right atrial pressure, cardiothoracic ratio, heart rate, and the plasma concentrations of atrial and brain natriuretic peptides in the CHF patients. Thus the plasma concentrations of both mAM and iAM were increased progressively in proportion to the severity of CHF. These results suggest that, though the role of iAM remains to be clarified, mAM acts against the further deterioration of heart failure in patients with CHF.  相似文献   

18.
AIM: Experimental data in heart failure models and an open trial of seven patients with idiopathic dilated cardiomyopathy have suggested beneficial effects of growth hormone on cardiac function. The aim of the present study was to evaluate growth hormone effects on cardiac function in a placebo-controlled study. METHODS: Twenty two patients with congestive heart failure of different aetiologies in NYHA II and III and an echocardiographic ejection fraction <0.45 were studied in a 3 month double-blind placebo-controlled study with growth hormone added to optimal heart failure therapy. Patients received either placebo (n=11) or recombinant human growth hormone (n=11) in an initial dose of 0.1 IU x kg(-1) week(-1) for 1 week, and thereafter 0.25 IU x kg(-1) week(-1) for the rest of the treatment period. Cardiac function was assessed by equilibrium radionuclide angiography and Doppler echocardiography. Functional capacity was evaluated by computerized bicycle exercise electrocardiography. RESULTS: Recombinant human growth hormone had no significant effect on systolic or diastolic cardiac function, exercise capacity or neuroendocrine activation. In addition, there was no overall improvement in functional class or dyspnoea grade. Insulin-like growth factor-I significantly increased demonstrating that the growth hormone had an endocrine effect. CONCLUSION: This is the first double-blind and placebo-controlled study of the administration, over 3 months, of recombinant human growth hormone in patients with congestive heart failure of different aetiologies. The treatment was safe and without serious side effects. However, no beneficial effects on cardiac function or structure could be detected.  相似文献   

19.
To determine the efficacy of mononitrate retard therapy in congestive heart failure 54 pts (42 males and 12 females, aged 67.2 +/- 8.7 yrs.) with NYHA functional class 1-3 and left ventricular ejection fraction less than 40% were investigated. Clinical examination, exercise treadmill test (ETT), ecg holter monitoring and echocardiography (echo-2D) were performed before and after 4 weeks of therapy with Olicard 40 mg Retard. 4 weeks treatment with mononitrate improved clinical parameters. The shift to lower functional NYHA class was observed in 12 cases (p < 0.01). Number of anginal pains per week was reduced from average 3.15 to 1.55 (p < 0.01). Mononitrate therapy improved exercise tolerance during ETT. Exercise time increased from 424 +/- 168 to 568 +/- 143 sec. (p < 0.001) as well as total workload in METS (3.6 +/- 1.4 vs. 4.9 +/- 1.9, p < 0.001). The time to 0.1 mV ischemic ST segment depression was extended from 215 +/- 149 to 357 +/- 173 sec. (p < 0.01). Holter monitoring revealed moderate increase in heart rate and significant reduction of ventricular arrhythmia (p < 0.05). No changes in systolic and diastolic echo-2D parameters were observed.  相似文献   

20.
Apoptosis has been shown to be involved in several processes during embryogenesis, but the ontogeny of apoptosis during lung development ahs not been studied. The goals of the current study were to determine if apoptosis occurs during lung development, and to determine the ontogeny of the changes in apoptosis that occur. We studied the ontogeny of apoptosis in vivo using lungs from 14-18-d gestation fetal rats, newborn rats, and 1-d-, 2-d-, 5-d-, and 10-d-old rat pups. Apoptosis was assessed by electron microscopy and the terminal deoxyribonucleotidyl transferase dUTP nick end-labeling assay. We compared the in vivo results with explants of 14-d gestation fetal rat lung placed in culture for 1-4 d because the biochemical development of the lung in organ culture has been shown to closely parallel the development of the lung in vivo. We found apoptosis of mesenchymal cells at the periphery of distal lung buds in early fetal lung (14-16-d gestation). Apoptosis of both mesenchyme and epithelium was present in later fetal lung (18-d gestation). There were no qualitative differences in apoptosis between in vivo fetal lung and explant cultures of fetal lung. There was a 14-fold increase in apoptosis at birth and in the first postnatal day of life (9-12% of cells) compared with fetal lung (0.6-1% of cells). This was followed by a rapid decline in the percentage of apoptotic cells to fetal levels at postnatal d 2-10. We conclude that apoptosis occurs in a spatially, temporally, and cell-specific manner during lung development. The number of cells undergoing apoptosis increases dramatically in the first day after birth.  相似文献   

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