A.J.M. Ferreira

N-Terminal–Pro-Brain Natriuretic Peptide Predicts Outcome After Hospital Discharge in Heart Failure Patients

Background—Heart failure (HF) is responsible for a huge burden in hospital care. Our goal was to evaluate the value of N-terminal–pro-brain natriuretic peptide (NT-proBNP) in predicting death or hospital readmission after discharge of HF patients. Methods and Results—We included 182 patients consecutively admitted to hospital because of decompensated HF. Patients were followed up for 6 months. The primary end point was death or readmission. Twenty-six patients died in hospital. The median admission NT-proBNP level was 6778.5 pg/mL, and the median level at discharge was 4137.0 pg/mL (P<0.001). Patients were classified into 3 groups: (1) decreasing NT-proBNP levels by at least 30% (n=82), (2) no significant modifications on NT-proBNP levels (n=49), and (3) increasing NT-proBNP levels by at least 30% (n=25). The primary end point was observed in 42.9% patients. Variables associated with an increased hazard of death and/or hospital readmission in univariate analysis were length of hospitalization, heart rate, signs of volume overload, no use of ACE inhibitors, higher NYHA class at discharge, admission and discharge NT-proBNP, and the change in NT-proBNP levels. The variation in NT-proBNP was the strongest predictor of an adverse outcome. Independent variables associated with an increased risk of readmission or death were signs of volume overload and the change in NT-proBNP levels. Conclusions—Variations in NT-proBNP levels are related to hospital readmission and death within 6 months. NT-proBNP levels are potentially useful in the evaluation of treatment efficacy and might help clinicians in planning discharge of HF patients. Whether therapeutic strategies aimed to lower NT-proBNP levels modify prognosis warrants future investigation.

Analysis of composite plates using higher-order shear deformation theory and a finite point formulation based on the multiquadric radial basis function method

In the present study the third-order theory of Reddy for composite laminated plates is discretized using a new type of meshless method, a finite point based on the multiquadric radial basis function method. The method allows a very accurate prediction of the field variables.

A formulation of the multiquadric radial basis function method for the analysis of laminated composite plates

Abstract The multiquadric radial basis functions (MQ) method is a recent mesh-free collocation method with global basis functions. The MQ method for the solution of partial differential equations was first introduced by Kansa in the early 1990s and showed exponential convergence for interpolation problems. In this paper we formulate and discuss the MQ method to the solution of moderately thick rectangular laminated composite plates. Numerical results show the high accuracy of the MQ method in the analysis of this class of structural problems.

Analysis of Composite Plates Using a Layerwise Theory and Multiquadrics Discretization

Abstract A layerwise shear deformation theory for composite laminated plates is discretized using multiquadrics. This new type of meshless method considers radial basis functions as the approximation method for both the differential governing equations and the boundary conditions. The combination of this layerwise theory and the multiquadrics discretization method allows a very accurate prediction of the field variables. Laminated composite and sandwich plates are analyzed.

Thick Composite Beam Analysis Using a Global Meshless Approximation Based on Radial Basis Functions

Composite beams are very common on primary structures, either in aeronautical or industrial applications. Shear deformations theories became fundamental in the analysis of laminated thick composite beams. Most of the approximation techniques so far have been based on finite element methods. In this article a meshless method based on radial basis functions is used for the analysis of thick laminated composite beams under a first-order shear deformation theory. This method provides very accurate solutions on isotropic and laminated beams.

Preliminary data on the potential usefulness of B-type natriuretic peptide levels in predicting outcome after hospital discharge in patients with heart failure

PURPOSE Among patients admitted for treatment of heart failure, we aimed to evaluate the value of B-type natriuretic peptide levels in predicting subsequent death or hospital readmission. SUBJECTS AND METHODS We observed and followed 50 consecutive patients admitted with decompensated heart failure. B-type natriuretic peptide levels were measured using an immunofluorometric assay at admission and at discharge. We followed patients for 6 months and ascertained readmissions for cardiovascular causes and death. RESULTS Forty-three patients were discharged. There were 20 events during follow-up (15 readmissions and 5 deaths). Mean (+/- SD) B-type natriuretic peptide levels decreased during the initial hospitalization, from 619 +/- 491 pg/mL to 328 +/- 314 pg/mL (P <0.001) among patients who were event free during follow-up, whereas declines were less marked among patients with hospital readmission or death (from 779 +/- 608 pg/mL to 643 +/- 465 pg/mL, P = 0.08). Among the 7 patients with in-hospital increases in B-type natriuretic peptide level, 6 had events, compared with 14 of the 36 patients whose levels declined (P = 0.04). An increase in B-type natriuretic peptide levels during hospital stay was associated with an increased event rate (hazard ratio [HR] = 3.3; 95% confidence interval [CI]: 1.3 to 8.8). Patients whose B-type natriuretic peptide level at discharge was above the median (321 pg/mL) had a somewhat higher rate of dying or being readmitted (HR = 2.3; 95% CI: 0.9 to 5.8). CONCLUSION These preliminary results in a small number of patients suggest that changes in B-type natriuretic peptide levels, as well as predischarge levels, are related to hospital readmission and death within 6 months.

Prognostic Value of High-Sensitivity C-Reactive Protein in Heart Failure: A Systematic Review

BACKGROUND Several studies have suggested that high-sensitivity C-reactive protein (hsCRP) is a strong independent predictor of acute myocardial infarction and cardiovascular death. In the specific heart failure (HF) context, a low-grade inflammatory state can contribute to HF progression. AIMS To perform a systematic review on the current knowledge about low-grade inflammation, as assessed by hsCRP, in the prediction of HF in general and in high-risk populations as well as its prognostic value in established HF. METHODS We used a computerized literature search in the Medline database using the following key words: C-Reactive Protein, Heart Failure, Cardiomyopathy, Cardiac Failure, Prognosis, and Death. Articles were selected if they had measurements of hsCRP in different patient samples and reference to outcomes in terms of morbidity and mortality. RESULTS hsCRP is associated with incident HF in general and high-risk populations and provides prognostic information in HF patients. In almost all studies, the association of hsCRP with clinical events was independent of other baseline variables known to influence morbidity and mortality. Very different cutoffs have been proposed in each context across studies. CONCLUSIONS The prognostic power of hsCRP, whether we consider incident HF or adverse outcomes in established HF, is consistent in different patient populations.

Prognostic information provided by serial measurements of brain natriuretic peptide in heart failure

BACKGROUND Brain natriuretic peptide (BNP) levels predict prognosis in heart failure patients. We aimed to evaluate if serial measurements of BNP can give additional prognostic information. METHODS Eighty-four patients with systolic dysfunction had two measurements of BNP with an interval of 8 to 12 months and were followed in order to register the occurrence of death. The study was observational and prospectively designed. During follow-up, patients were treated according to state of the art. Physicians were kept blind to BNP levels. RESULTS The median follow-up was 1190 days. The median initial BNP level was 260.4 pg/ml and decreased to 123 pg/ml in the second measurement (P=0.001). The decrease in BNP was significantly associated with ACE-i dosage and with the use of a beta-blocker. All-cause mortality was 20.2%. Patients whose initial BNP level was above the median had a significantly higher hazard of dying (HR 2.96, 95% CI 1.06-8.26). The same was observed for those whose BNP increased between the first and the second measurement (HR 2.64, 95% CI 1.00-7.00). In multivariable analysis, baseline BNP above the median and increasing BNP were associated with shorter survival. CONCLUSIONS Higher baseline BNP and the increasing levels during follow-up were independently associated with mortality. The decrease in BNP levels was proportional to ACE-i dosage and larger among patients on beta-blockers. These results confirm the prognostic information provided by BNP determination and suggest that serial measurements give additional prognostic information.

The different phases in the precipitation of dicalcium phosphate dihydrate

AbstractTheprecipitationofdicalciumphosphatedihydrate,brushite,bymixingacalciumhydroxidesuspensionandanorthophosphoricacidsolutioninequimolarquantities,hasbeeninvestigatedinabatchsystemat25C.Theconcentrationofcalciumhydroxideandorthophosphoricacid,beforemixing,rangedfrom50to300mmoldm 3 .ThephasefirstprecipitatedisCa 5 OH(PO 4 ) 3 ,hydroxyapatite.Theprecipitationprocessofbrushiteisdividedintofivestagesandissimilarforallinitialexperimentalconditions.Theextensionofeachstagevarieswiththeinitialreagents’concentrations.ThesestagesarediscussedindividuallyasafunctionofpHandreagents’concentrations.TheprecipitatewasanalysedbyscanningelectronmicroscopyandX-raydiffraction.Thesolubilityofbrushitewasdeterminedat25C,30Cand35C,andinthepHrange4.5–8.r 2003ElsevierScienceB.V.Allrightsreserved. PACS: 81.30.Mh;81.10.Dn;64.60.MyKeywords: A1.Precipitation;A1.Solubility;B1.Brushite;B1.Hydroxyapatite 1. IntroductionTheprecipitationofcalciumphosphatehasbeenstudiedbyvariousauthorsunderdifferentcondi-tions.Dependingontheprecipitationconditions,liketemperature,levelofsupersaturation,pHandinitialconcentrationofreagents,onecanobtaindifferentcalciumphosphatephases[1–5].Oneofthemisthedicalciumphosphate dihydrate (CaHPO

Analysis of Functionally Graded Plates by a Robust Meshless Method

The analysis of static deformations of functionally graded plates is performed by using the collocation method, the radial basis functions and a higher-order shear deformation theory. The collocation method is truly meshless, allowing a fast and simple domain and boundary discretization. We select the shape parameter in the radial basis functions by an optimization procedure based on the cross-validation technique, and use the Mori-Tanaka homogenization technique to deduce effective properties of functionally graded materials. Numerical tests show that the method is reliable, robust and produces accurate results.