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BACKGROUND: The prevalence of chronic heart failure (CHF) with systolic dysfunction is increasing. Plasma natriuretic peptides have been envisaged as diagnostic and predictive markers. AIMS: To investigate the relationship between the levels of B-type natriuretic peptide (BNP) and A-type natriuretic peptide (ANP) and the clinical and functional parameters of CHF in outpatients with CHF at baseline, compared with normal healthy controls; to find out the differences in a randomised controlled trial between patients treated with an angiotensin-converting enzyme (ACE) inhibitor, captopril, or an angiotensin receptor blocker (ARB), irbesartan. These differences were assessed throughout the six-month treatment period and at the sixth month. METHODS: Plasma BNP (pmol/L) and ANP (pmol/L) were determined in 68 hypertensive patients with dilated cardiomyopathy, NYHA class III-IV and ejection fraction (EF) < or = 40%, and in 26 normal controls. Statistical analysis for BNP and ANP was done by Students t-test. The patient group was randomly subdivided into two subgroups of 34 patients, each treated with either an ARB, irbesartan, or an ACE inhibitor (ACE-I), captopril. BNP and ANP were measured in both subsamples and correlated with clinical, functional and neurohormonal parameters throughout a follow-up period of six months and at the sixth month. RESULTS: The mean EF in the patient sample was 33.43+/-6.52% and in the controls was 61.96 +/-3.53% (p=0.000). The mean BNP (pmol/L) in patients was 44.78+/-54.36 and in the controls was 7.12+/-8.28 (p=0.000) and the mean ANP (pmol/L) was 30.32+/-25.97 in patients and 11.18+/-7.92 in controls (p=0.000). A statistically significant difference was found between patients and healthy controls. Significant correlations were found between natriuretic peptides and EF. Between the baseline phase and the sixth month, BNP and ANP decreased significantly in the ARB group. At the sixth month, both BNP and ANP were lower in the ARB group. Evidence of clinical benefit was found with both ARB or ACE-I treatment throughout the six months, with patients moving from classes III and IV to class II NYHA. Improvement of EF was also found, with transition of patients with lower EF (even <30%) to higher values. EF was higher in the ARB group at the sixth month. CONCLUSIONS: BNP and ANP can be useful diagnostic tools in hypertensive CHF patients with moderate-to-severe LV dysfunction. The decrease in BNP and ANP in the ARB group throughout six months, as well as the lower value at the sixth month, suggest a prognostic value of these parameters.  相似文献   
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There is a lack of information on the prognostic value of local high velocity in coronary arteries during echocardiography. The aim of the study described here was to define the prognostic value of local velocity >70?cm/s in the left main, anterior or circumflex artery during echocardiography. There were 412 patients in the prospective study. Death, non-fatal myocardial infarction, acute pulmonary edema, acute coronary syndrome and revascularization were defined as major adverse cardiac events (MACEs). Over 10.5?mo, there were 207 patients with MACEs. Seventeen patients died, 10 had non-fatal acute cardiac events and 184 underwent revascularization. Deaths occurred in patients with high local velocity (6.4% vs. 0%, p?<0.009). Acute cardiac events occurred in 10% versus 0% (p?<0.003). MACEs were observed in 62% versus 0% (p?<0.0000001). Only maximal velocity was an independent prognostic predictor of death (odds ratio?=?1.02, 95% confidence interval: 1.01–1.03, p?<0.02) and MACEs (odds ratio?=?1.04, 95% confidence interval: 1.02–1.05, p?<0.0001). The success rate of coronary artery visualization for at least one segment was 91%.  相似文献   
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The purpose of this study was to longitudinally compare the sensitivity of previously documented paradigms for measuring balance control during gait following a concussion. We hypothesized that gait with a concurrent cognitive task would be most sensitive to the effects of concussion on dynamic balance control. Individuals with concussion (n = 30) and matched controls (n = 30) performed a single task of level walking, attention divided walking, and an obstacle-crossing task at two heights. Testing occurred four times post-injury. Balance control during gait was assessed with whole-body center of mass and center of pressure motion. The single-task level walking task did not result in any significant differences in balance control between individuals with concussion and control subjects. Within 48 hours post-injury, individuals with concussion walked slower and allowed less motion of their center of mass in the sagittal plane when attention was divided during walking, but there were no group differences by day 6 for this task. Group differences in balance control during obstacle crossing was unremarkable during the first two testing sessions, but by day 14 individuals with concussion displayed less mediolateral motion of their center of mass. Attention divided gait is able to better distinguish gait adaptations immediately following a concussion, but obstacle crossing can be used further along in the recovery process to detect new gait adaptations.  相似文献   
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