ISSN:0009-7322    

出版商:OVID    

年代:2003

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:2003

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:2003

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Background—Although previous work has suggested that anemia is associated with an increased mortality in selected patients with congestive heart failure (CHF), little is known about the prevalence and predictors of anemia, or whether anemia is an independent prognostic factor in unselected, community-based patients with CHF.Methods and Results—We analyzed a population-based cohort of patients with new-onset CHF from a database of patients discharged from 138 acute-care hospitals in Alberta, Canada, between April 1993 and March 2001. Logistic regression, Kaplan-Meier survival analyses, and Cox proportional hazards model were used. Among the 12 065 patients with CHF (median age 78 years), 17% had anemia, 58% of whom had anemia of chronic disease. After adjustment for clinical and demographic variables, patients with anemia were more likely to be older (odds ratio [OR] 1.01 per year) and female (OR 1.2 [95% confidence interval 1.1 to 1.3]) and to have a history of chronic renal insufficiency (OR=3.2 [95% confidence interval 2.8 to 3.6]), or hypertension (OR 1.3 [95% confidence interval 1.2 to 1.5]). Hazard ratios for mortality, adjusting for covariates, were 1.34 (1.24 to 1.46) in anemic patients, and 1.36 (1.23 to 1.50) in those patients with anemia of chronic disease.Conclusions—In this large cohort of community-dwelling patients with CHF, anemia is common and an independent prognostic factor for mortality. Further research into the mechanisms of anemia in CHF and randomized controlled trials to test whether correction of anemia improves prognosis in CHF are needed.

ISSN:0009-7322    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Background—Anemia frequently occurs in chronic heart failure (CHF) patients and is associated with a poor prognosis. A low hematocrit may result from an increased plasma volume (hemodilution) or from reduced red blood cell volume (true anemia). The prevalence and clinical outcome of CHF patients with hemodilution is unknown.Methods and Results—The prevalence of anemia and its effect on outcome was examined in 196 patients with CHF. The prevalence of hemodilution was assessed in a subset of 37 ambulatory anemic patients with I131-tagged albumin to measure red blood cell and plasma volume. Clinical outcome was monitored. Sixty-one percent of the CHF patients were anemic. The prevalence of anemia increased from 33% in patients with New York Heart Association class II heart failure to 68% in class IV CHF patients. Survival was reduced in anemic patients compared with patients with a normal hematocrit (P<0.05). In the subset of 37 anemic patients, 17 patients (46%) had hemodilution and 20 patients (54%) had a true anemia. Nine patients with hemodilution died or underwent urgent transplant compared with 4 patients in the true anemia group (P<0.04).Conclusion—Hemodilution is common in CHF patients. Anemia is associated with a poor prognosis in CHF. Patients with hemodilution tend to do worse than patients with true anemia, which suggests that volume overload may be an important mechanism contributing to the poor outcome in anemic CHF patients.

ISSN:0009-7322    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Background—The mechanisms responsible for the association between advanced age and atherosclerotic diseases are not clear. Because atherosclerosis develops in response to local endothelial injuries, we investigated the effect of aging on vascular healing and reendothelialization.Methods and Results—Endothelium denudation was performed by balloon angioplasty of the iliac arteries in young and old New Zealand White rabbits. Planimetric analysis after Evans Blue staining at 28 days after injury showed a significant decrease in reendothelialization in old versus young animals, which was associated with an important increase in neointimal formation in old rabbits. Vascular endothelial growth factor (VEGF) was rapidly induced after balloon injury. However, arterial VEGF expression was significantly reduced in old versus young animals. To confirm the role of VEGF in the age-dependent impairment of reendothelialization, an adenoviral vector encoding for VEGF165(adeno-VEGF) was locally delivered at the time of iliac artery angioplasty. Compared with animals treated with the control vector (adeno-&bgr;Gal), reendothelialization was significantly improved and neointimal formation reduced in old rabbits treated with adeno-VEGF.Conclusions—These results document for the first time an age-dependent impairment of reendothelialization after arterial injury. Our study indicates that VEGF supplementation may represent a useful strategy to accelerate reendothelialization and improve vascular healing in the context of aging.

ISSN:0009-7322    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Background—Phosphodiesterase type 5 (PDE5) inhibitors (eg, sildenafil) are a novel, orally active approach to the treatment of pulmonary arterial hypertension. The role of natriuretic peptides in the response to sildenafil was examined in mice lacking NPR-A, a guanylyl cyclase-linked natriuretic peptide receptor, in which pulmonary hypertension was induced by hypoxia.Methods and Results—Mice homozygous for NPR-A (NPR-A+/+) and null mutants (NPR-A−/−) were studied. Sildenafil inhibited the pressor response to acute hypoxia in the isolated perfused lungs of both genotypes. This effect was greater in the presence of atrial natriuretic peptide in the perfusate inNPR-A+/+mice but notNPR-A−/−animals. In vivo, NPR-A mutants had higher basal right ventricular (RV) systolic pressures (RVSPs) than didNPR-A+/+mice, and this was not affected by 3 weeks of treatment with sildenafil (25 mg · kg−1· d−1). Both genotypes exhibited a rise in RVSP and RV weight with chronic hypoxia (10% O2for 21 days); RVSP and RV weight were reduced by continuous sildenafil administration inNPR-A+/+mice, but only RVSP showed evidence of a response to the drug inNPR-A−/−mice. The effect of sildenafil on hypoxia-induced pulmonary vascular muscularization and cyclic GMP levels was also blunted inNPR-A−/−mice.Conclusions—The natriuretic peptide pathway influences the response to PDE5 inhibition in hypoxia-induced pulmonary hypertension, particularly its effects on RV hypertrophy and vascular remodeling.

ISSN:0009-7322    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Background—Current pharmacotherapeutic options for high-risk non-ST-segment elevation acute coronary syndrome patients include aspirin, clopidogrel, heparin, and platelet glycoprotein IIb/IIIa inhibition. A key issue of uncertainty is the safety and efficacy of combination glycoprotein IIb/IIIa inhibitor and low-molecular-weight heparin therapy.Methods and Results—We randomized 746 patients with rest ischemic discomfort within 24 hours after the onset of symptoms and ST-segment deviation and/or elevation of serum cardiac markers to receive open-label enoxaparin (1 mg/kg subcutaneously twice daily) or unfractionated heparin (70-U/kg bolus; 15 U · kg−1· h−1infusion, titrated to an activated partial thromboplastin time of 1.5 to 2 times control) for 48 hours. All patients received aspirin and eptifibatide (180-&mgr;g/kg bolus; 2 &mgr;g · kg−1· min−1infusion). Major non-coronary artery bypass surgery-related bleeding at 96 hours (primary safety outcome) was significantly lower among enoxaparin-treated patients than among heparin-treated patients (1.8% versus 4.6%,P=0.03). Minor bleeding was more frequent in the enoxaparin group (30.3% versus 20.8%,P=0.003). Patients in the enoxaparin group were less likely to experience ischemia as detected by continuous ECG evaluation (primary efficacy outcome) during the initial (14.3% versus 25.4%,P=0.0002) and subsequent (12.7% versus 25.9%,P<0.0001) 48-hour monitoring periods. Death or myocardial infarction at 30 days was significantly lower in the enoxaparin group (5% versus 9%,P=0.031).Conclusions—When aspirin and eptifibatide are used in high-risk non-ST-segment elevation acute coronary syndrome patients, enoxaparin improves outcomes (determined on the basis of better safety and efficacy) compared with currently recommended unfractionated heparin therapy and provides a useful novel alternative therapeutic strategy.

ISSN:0009-7322    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Background—Elevated levels of C-reactive protein (CRP) are associated with an increased risk of coronary events, but whether inflammation is associated with inducible ischemia in patients with stable coronary disease is unknown.Methods and Results—We recruited patients with known coronary disease from 2 VA Medical Centers and 1 University-based medical center for the Heart and Soul Study. We measured CRP levels in 118 participants who had exercise-induced ischemia and in 111 who did not have inducible ischemia, as determined by stress echocardiography. We used logistic regression to examine the risk of exercise-induced ischemia associated with elevated CRP. We found that 75% (39/52) of participants in the highest CRP category (>0.38 mg/dL) had inducible ischemia, compared with 45% (79/177) in the lower 4 categories combined (adjusted odds ratio 4.2; 95% confidence interval 1.6 to 11;P=0.004). However, this association differed in users and nonusers of &bgr;-blockers and statins. Among 89 participants who did not use &bgr;-blockers, 93% in the highest CRP category had exercise-induced ischemia, compared with 42% in the lower 4 categories (P=0.03). Among 67 participants who did not use statins, 94% in the highest CRP category had exercise-induced ischemia, compared with 44% in the lower 4 categories (P=0.009). We did not observe a significant association between CRP and ischemia among participants who were treated with either of these medications.Conclusion—Elevated CRP levels are associated with inducible ischemia in patients with stable coronary disease, particularly among those not treated with &bgr;-blockers or statins.

ISSN:0009-7322    

出版商:OVID    

年代:2003

数据来源: OVID