首页 | 官方网站   微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
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   

2.
3.
Originally developed as an antianginal agent, amiodarone was soon found to have antiarrhythmic properties and to be a non-competitive inhibitor of alpha and beta-adrenergic receptors. Many trials studying the use of amiodarone in patients with heart failure have now been performed and are reviewed in this article. The trials appear to show that amiodarone possesses significant antiarrhythmic activity, even in heart failure patients. The drug appears to be well tolerated and proarrhythmia is uncommon. Based on the findings of a large Argentinian randomised trial (GESICA) and the Congestive Heart Failure Survival Trial of Antiarrhythmic Therapy (CHF STAT), it would appear there is a role for amiodarone in patients with non-ischaemic cardiomyopathy, but prospective studies are required to confirm this. The benefit of amiodarone in patients with non-ischaemic cardiomyopathy might be related to the beta-blocking effect that is seen with the use of conventional beta-blockers. Further studies, including the Sudden Cardiac Death Heart Trial (SCD HeFT), should help determine the role of amiodarone in heart failure patients.  相似文献   

4.
Most arteriovenous malformations usually arise from pre-existing named vessels. We report an unusual variant of an arteriovenous malformation. An 18-year-old man presented with a painful swelling of the right forearm. Arteriograms suggested branches of the anterior interosseous artery were feeding the malformation. Operative findings however, revealed the presence of a persistent median artery, which was contributing branches to the swelling.  相似文献   

5.
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   

6.
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   

7.
8.
9.
Nasal passage geometry was measured by acoustic rhinometry in 8 healthy medical students (5 males and 3 females, 21-29 years old; mean age 24 years) after 6 min in different postures of head and body. The minimum cross-sectional area (A-min) and volume between the nostril and 7 cm posteriorly were measured on both sides. When changing from sitting to horizontal the total airway dimension (i.e., the sum of A-min for the two sides) decreased by about 16% (Mean +/- SD = 0.19 +/- 0.14 cm2), and when standing up it increased by about 12% (0.14 +/- 0.13 cm2). A-min seemed more sensitive than volume to detecting postural changes. Including the variation between the cavities, the coefficient of variation (CV = SD/Mean) for area was 24.8 +/- 6.7 and for volume 22.4 +/- 6.4 for the 8 subjects. For the total nasal airway passage the corresponding figures were 12.9 +/- 3.9 and 10.9 +/- 5.5. These figures are considerably higher than for subjects measured only in the sitting position under comparable circumstances. In conclusion, our findings indicate a composite response of the nasal cavity mucosa to both systemic (hydrostatic) and local conditions, probably induced by vascular and cutaneous reflexes. These factors must be taken into account in studies of environmental, clinical, and pharmacological conditions.  相似文献   

10.
11.
12.
The malaria parasite life cycle presents several targets for attack, but these different parts of the life cycle are susceptible to different types of host immune response. For example, the sporozoite is most sensitive to immune antibody, while liver stage parasites can be eliminated by cytotoxic T lymphocytes. Attachment of merozoites to erythrocytes, on the other hand, can be blocked by antibody. Convincing experimental evidence shows that completely protective immunity to malaria can be induced. The challenge now is to design recombinant or synthetic vaccines that induce the right types of immune responses to specific life cycle stages. This requires the identification and characterization of B- and T-lymphocyte epitopes expressed by the parasite or by parasitized host cells. These epitopes must be incorporated into a delivery system that maximizes the interaction between the vaccine epitopes and the host immune system. Many epitopes from several parts of the life cycle are already characterized; development of multivalent vaccines, that is, vaccines which contain immunogens from more than one part of the life cycle, is a promising area for research efforts.  相似文献   

13.
14.
Vesnarinone is a new and novel inotropic drug that has unique and complex mechanisms of action. It inhibits phosphodiesterase, thereby leading to increased intracellular calcium, and also affects numerous myocardial ion channels, resulting in the prolongation of the opening time of sodium channels and the decrease in the delayed outward and inward rectifying potassium current. In vitro, it has also demonstrated significant effects on cytokine production, which may account for some of its observed clinical benefits. Hemodynamic studies in humans with congestive heart failure reveal that vesnarinone can improve ventricular function. Placebo-controlled studies in large numbers of patients with heart failure have suggested a morbidity and mortality benefit with a 60 mg daily dose. There is increased mortality with vesnarinone at the 120 mg daily dose, however, suggesting a narrow therapeutic window for the drug. Its predominant toxic side effect is a 2% incidence of reversible neutropenia.  相似文献   

15.
16.
17.
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   

18.
Anomalous systemic arterial supply to a lobe of the lung is a rare cause of pulmonary hypertension and congestive heart failure in the newborn period. We report the presentation and successful treatment of a neonate with this unusual anatomy. Proper diagnosis required both echocardiography and aortography, and surgical resection of the involved lobe was curative.  相似文献   

19.
20.
LVEF should be measured in all elderly persons with CHF Underlying causes and precipitating causes of CHF should be treated. Persons with CHF associated with abnormal LVEF should be treated with a low sodium diet, diuretics, and ACE inhibitors. If CHF persists, digoxin should be added. If CHF still persists, isosorbide dinitrate plus hydralazine should be added. If CHF still persists, a beta blocker should also be added. However, calcium channel blockers should not be used. Persons with CHF associated with normal LVEF should be treated with a low sodium diet, diuretics, and ACE inhibitors. If CHF persists, a beta blocker, isosorbide dinitrate plus hydralazine, or a calcium channel blocker should be added to the therapeutic regimen. If sinus rhythm is present, digoxin should not be used. Persons with CHF and abnormal or normal LVEF unable to tolerate ACE inhibitors should be treated with losartan.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司    京ICP备09084417号-23

京公网安备 11010802026262号