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71.
72.
The evaluation of patients admitted at the emergency department (ED) for chest pain is challenging and involves many different clinical specialists including emergency physicians, laboratory professionals and cardiologists. The preferable approach to deal with this issue is to develop joint protocols that will assist the clinical decision-making to quickly and accurately rule-out patients with non life-threatening conditions that can be considered for early and safe discharge or further outpatient follow-up, rule-in patients with acute coronary syndrome and raise the degree of alert of the emergency physicians on non-cardiac life-threatening emergencies. The introduction of novel biomarkers alongside the well-established troponins might support this process and also provide prognostic information about acute short-term or chronic long-term risk and severity. Among the various biomarkers, copeptin measurement holds appealing perspectives. The utility of combining troponin with copeptin might be cost-effective due to the high negative predictive value of the latter biomarker in the rule-out of an acute coronary syndrome. Moreover, in the presence of a remarkably increased concentration (e.g., more than 10 times the upper limit of the reference range), to reveal the presence of acute life-threatening conditions that may not necessarily be identified with the use of troponin alone. The aim of this article is to review current evidence about the clinical significance of copeptin testing in the ED as well as its appropriate placing within diagnostic protocols.  相似文献   
73.
PURPOSE: Patients with stable heart failure often wish to spend time at altitudes above those of their residence. However, it is not known whether they can safely tolerate ascent to high altitudes or what its effects on work capacity may be.SUBJECTS AND METHODS: We studied 14 normal subjects and 38 patients with clinically stable heart failure, 12 of whom had normal workload [peak exercise oxygen consumption (VO(2)) greater than 20 mL/min/kg], 14 of whom had slightly diminished workload (peak VO(2) 20 to 15 mL/min/kg), and 12 of whom had markedly diminished workload (peak VO(2) less than 15 mL/min/kg) at baseline. All performed cardiopulmonary exercise tests with inspired oxygen fractions equal to those at 92, 1,000, 1,500, 2,000, and 3,000 m, and maximum achieved work rates (mean +/- SD) were measured.RESULTS: All subjects completed the trial; no test was interrupted because of arrhythmia, angina, or ischemia. Maximum work rate decreased in parallel with increasing simulated altitude. The percentage decrease was greater for patients with heart failure and was most marked among those with the lowest workload at baseline. Maximum achieved work rate declined by 3% +/- 4% per 1,000 m in normal subjects, by 5% +/- 3% (P <0.01) in patients with heart failure with normal workload, by 5% +/- 4% (P <0.01) in patients with slightly diminished workload, and by 11% +/- 5% (P <0.01 vs normal subjects and vs the other patients with heart failure) in patients with markedly reduced workload.CONCLUSION: Patients with stable heart failure who ascend to higher altitudes should expect to have a reduction in maximum physical activity in proportion to their exercise capacity at sea level.  相似文献   
74.
BACKGROUND: Previous studies have shown that in the treated fraction of the hypertensive population, blood pressure (BP) control is less common for systolic BP (SBP) than for diastolic BP (DBP) as measured in the physician's office. Whether this phenomenon is artifactually attributable to a temporary increase in BP owing to a "white-coat" effect or represents a true rarity of SBP control in daily life is unknown. METHODS: Data were obtained from the PAMELA (Pressioni Arteriose Monitorate E Loro Associazioni) study population, which involved individuals ranging in age from 25 to 74 years who were representative of the residents of Monza (a city near Milan, Italy) and who were stratified according to sex. Office (an average of 3 sphygmomanometric measurements), home (an average of morning and evening self-measurements using a semiautomatic device), and 24-hour ambulatory (average of measurements performed every 20 minutes during the day and at night) BP values were obtained in all study subjects. In the treated hypertensive patients, BP was regarded as controlled if office values were less than 140 (SBP) or 90 (DBP) mm Hg. Home and 24-hour average SBP and DBP were regarded as controlled if the values were lower than 132/83 and 125/79 mm Hg, respectively. RESULTS: In the study participants (n = 2051), the number of patients with hypertension who were receiving antihypertensive treatment was 398, or approximately 42% of all individuals with hypertension. In-office SBP control by treatment was less frequent than DBP control (29.9% vs 41.5%, P<.05). This was also the case when home and 24-hour SBP and DBP control was considered (38.3% vs 54.6% and 50.8 vs 64.9%, respectively, P<.05 for both). CONCLUSIONS: In the PAMELA population, SBP control by treatment was much less frequent than DBP control by treatment. This was the case not only for office BP values but also for home and 24-hour BP values, demonstrating that inadequate SBP control is not limited to artificial BP-measuring methods but occurs in daily life.  相似文献   
75.
Exercise-induced hemoconcentration is a useful mechanism, particularly in heart failure, because it increases oxygen content of blood, perfusing the working muscles; in 50 normal subjects and 50 patients with congestive heart failure, hemoglobin at peak exercise increased by 7 +/- 3% and 5 +/- 3%, respectively. Hemoconcentration was due to fluid flux out of the vascular bed, likely through oncotic forces related to intracellular lactate accumulation and not to red blood cell recruitment from other organs (spleen), because hemoglobin increase, as a percentage, was similar to plasma protein increase.  相似文献   
76.
OBJECTIVES: We sought to investigate the possibility that lung diffusing capacity reduction observed in chronic heart failure is reversible in the short term. BACKGROUND: Mechanical properties of the lung usually ameliorate with antifailure treatment including drugs, ultrafiltration and heart transplantation, whereas lung diffusion rarely improves. METHODS: We studied the mechanical properties of the lung (pulmonary function tests with determination of alveolar volume, extravascular lung fluids and lung tissue), lung diffusion for carbon monoxide (DLco), including membrane diffusing capacity (Dm), pulmonary capillary blood volume (Vc) and pulmonary hemodynamics, in 28 patients with stable chronic heart failure, before a single session of extracorporeal ultrafiltration (3,973 +/- 2200 ml) and four days thereafter. Lung mechanics and diffusion were also evaluated in 18 normal subjects. RESULTS: Vital capacity, forced expiratory volume (1 s) and maximal voluntary ventilation were lower in patients when compared with normal subjects, and increased after ultrafiltration from 2.1 +/- 0.7 to 2.5 +/- 0.7(1)*, 1.7 +/- 0.5 to 2.0 +/- 0.6(1)* and 67 +/- 25 to 79 +/- 26 (1/min)*, respectively (* p < 0.02 vs. pre-ultrafiltration). Post-ultrafiltration alveolar volume was augmented, while lung tissue, body weight (approximately 6 kg), chest X-ray extravascular lung water score and pulmonary vascular pressure were reduced. Heart dimensions (echocardiography) remained unchanged. DLco, Dm and Vc were 29.0 +/- 5.0 ml/min/mm Hg, 47.0 +/- 11.0 ml/min/mm Hg, 102 +/- 20 ml in normal subjects and 17.1 +/- 4.0#, 24.1 +/- 6.5#, 113 +/- 38 and 17.0 +/- 5.0#, 24.8 +/- 7.9#, 100 +/- 39 in patients before and after ultrafiltration, respectively (# = p < 0.01 vs. controls). CONCLUSIONS: In chronic heart failure, ultrafiltration improves volumes and mechanical properties of the lung by reducing lung fluids. Diffusion is unaffected by ultrafiltration, suggesting that, in chronic heart failure, the alveolar-capillary membrane abnormalities are fluid-independent.  相似文献   
77.
BACKGROUND--Hypovolaemia stimulates the sympathoadrenal and renin systems and water retention. It has been proposed that in congestive heart failure reduction of cardiac output and any associated decrease in blood pressure cause underfilling of the arterial compartment, which promotes and perpetuates neurohumoral activation and the retention of fluid. This study examined whether an intravascular volume deficit accounts for patterns that largely exceed the limits of a homoeostatic response, which are sometimes seen in advanced congestive heart failure. METHODS AND RESULTS--In 22 patients with congestive heart failure and water retention the body fluid mass was reduced by ultrafiltration and the neurohumoral reaction was monitored. A Diafilter, which was part of an external venous circuit was regulated to produce 500 ml/hour of ultrafiltrate (mean (SD) 3122 (1199) ml) until right atrial pressure was reduced to 50% of baseline. Haemodynamic variables, plasma renin activity, noradrenaline, and aldosterone were measured before and within 48 hours of ultrafiltration. After ultrafiltration, which produced a 20% reduction of plasma volume and a moderate decrease in cardiac output and blood pressure (consistent with a diminished degree of filling of the arterial compartment), there was an obvious decrease in noradrenaline, plasma renin activity, and aldosterone. In the next 48 hours plasma volume, cardiac output, and blood pressure recovered; the neurohumoral axis was depressed; and there was a striking enhancement of water and sodium excretion with resolution of the peripheral oedema and organ congestion. The neurohumoral changes and haemodynamic changes were not related. There were significant correlations between the neurohumoral changes and increase in urinary output and sodium excretion. CONCLUSIONS--In advanced congestive heart failure arterial underfilling was not the main mechanism for activating the neurohumoral axis and retaining fluid. Because a decrease in circulating hormones was associated with reabsorption of extravascular fluid it is likely that hypoperfusion and/or congestion of organs, such as the kidney and lung, reduce the clearance of circulating noradrenaline and help to keep plasma concentrations of renin and aldosterone raised. A positive feedback loop between fluid retention and plasma hormone concentrations may be responsible for progression of congestive heart failure.  相似文献   
78.
In cases of reconstruction of a discontinuity defect of the mandible, the surgeon has a major responsibility to maximize function as well as cosmetics and to preserve quality of life, restoring mastication, speech, and appearance. Treatment of mandibular discontinuity defects is a complex process and, among other methods, includes the use of free vascularized flaps. A variety of donor sites have been used for this purpose, including the iliac crest, radius, scapula, and fibula.At this time, the iliac crest free flap represents a versatile reconstruction method after mandibular ablation. This article reports a clinical case using the iliac crest free flap for comprehensive reconstruction of discontinuity defects in the mandible after resections of an aggressive odontogenic tumor. The immediate implant positioning reduced the number of surgical procedures and the rehabilitation time.  相似文献   
79.

Background

There are no national data on the magnitude and pattern of chronic kidney disease (CKD) in India. The Indian CKD Registry documents the demographics, etiological spectrum, practice patterns, variations and special characteristics.

Methods

Data was collected for this cross-sectional study in a standardized format according to predetermined criteria. Of the 52,273 adult patients, 35.5%, 27.9%, 25.6% and 11% patients came from South, North, West and East zones respectively.

Results

The mean age was 50.1 ± 14.6 years, with M:F ratio of 70:30. Patients from North Zone were younger and those from the East Zone older. Diabetic nephropathy was the commonest cause (31%), followed by CKD of undetermined etiology (16%), chronic glomerulonephritis (14%) and hypertensive nephrosclerosis (13%). About 48% cases presented in Stage V; they were younger than those in Stages III-IV. Diabetic nephropathy patients were older, more likely to present in earlier stages of CKD and had a higher frequency of males; whereas those with CKD of unexplained etiology were younger, had more females and more frequently presented in Stage V. Patients in lower income groups had more advanced CKD at presentation. Patients presenting to public sector hospitals were poorer, younger, and more frequently had CKD of unknown etiology.

Conclusions

This report confirms the emergence of diabetic nephropathy as the pre-eminent cause in India. Patients with CKD of unknown etiology are younger, poorer and more likely to present with advanced CKD. There were some geographic variations.  相似文献   
80.
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