Association of severe coronary stenosis with subclinical left ventricular dysfunction in the absence of infarction

Background. Regional left ventricular (LV) dysfunction may occur in patients with coronary artery disease (CAD) in the absence of infarction, but the causes of this phenomenon are unclear. We sought to identify whether changes in regional LV function were related to stenosis severity, using sensitive new ultrasound markers of function. Methods: We studied 67 individuals with no history of infarction and with normal LV systolic function: 49 patients with CAD and 18 control subjects without CAD. All patients underwent color Doppler tissue imaging, integrated backscatter (IB), anatomic M-mode echocardiography, and strain rate imaging to detect changes in structure and function. Peak early and late diastolic myocardial velocity, cyclic variation of IB, wall thickness, and percent wall thickening were measured in each basal and mid segment. Strain rate and peak systolic strain were calculated in each wall. CAD was defined as greater than or equal to 50% diameter stenosis. Normokinetic segments (n = 354) subtended by CAD were divided according to stenosis severity into 3 groups: group 1 (subtended by 50%-69% stenosis); group 2 (subtended by 70%-98% stenosis); and group 3 (subtended by greater than or equal to99% stenosis). Each parameter in each group was compared with that in 216 segments from control subjects. Results: Segments subtended by significant CAD showed lower peak early and late diastolic myocardial velocity compared with control segments. Group 3 showed significantly lower myocardial velocities than group 2 for both peak early (4.8 +/- 1.8 vs 6.0 +/- 2.0 cm/s, P

Effects of glucose-insulin-potassium infusion on chronic ischaemic left ventricular dysfunction

Background: Glucose-insulin-potassium (GIK) infusion improves cardiac function and outcome during acute ischaemia. Objective: To determine whether GIK infusion benefits patients with chronic ischaemic left ventricular dysfunction, and if so whether this is related to the presence and nature of viable myocardium. Methods: 30 patients with chronic ischaemic left ventricular dysfunction had dobutamine echocardiography and were given a four hour infusion of GIK. Segmental responses were quantified by improvement in wall motion score index (WMSI) and peak systolic velocity using tissue Doppler. Global responses were assessed by left ventricular volume and ejection fraction, measured using a three dimensional reconstruction. Myocardial perfusion was determined in 15 patients using contrast echocardiography. Results: WMSI (mean (SD)) improved with dobutamine (from 1.8 (0.4) to 1.6 (0.4), p < 0.001) and with GIK (from 1.8 (0.4) to 1.7 (0.4) p < 0.001); there was a similar increment for both. Improvement in wall motion score with GIK was observed in 55% of the 62 segments classed as viable by dobutamine echocardiography, and in 5% of 162 classed as non-viable. There was an increment in peak systolic velocity after both doputamine echocardiography (from 2.5 (1.8) to 3.2 (2.2) cm/s, p < 0.01) and GIK (from 3.0 (1.6) to 3.5 (17) cm/s, p < 0.001). The GlK effects were not mediated by changes in pulse, mean arterial pressure, lactate, or catecholamines, nor did they correlate with myocardial perfusion. End systolic volume improved after GlK (p = 0.03), but only in 25 patients who had viable myocardium on dobutom ne echocardiography. Conclusions: In patients with viable myocardium and chronic left ventricular dysfunction, GlK improves wall motion score, myocardial velocity, and end systolic volume, independent of effects on haemodynamics or catecholamines. The response to GlK is observed in areas of normal and abnormal perfusion assessed by contrast echocardiography.

Left ventricular dyssynchrony predicts benefit of cardiac resynchronization therapy in patients with end-stage heart failure before pacemaker implantation

We evaluated patients with end-stage heart failure who have a high likelihood of response to cardiac resynchronization therapy (biventricular pacing). It appears that 20% of patients do not respond to this expensive therapy despite the use of selection criteria (dilated cardiomyopathy, heart failure, New York Heart Association class II or IV, left ventricular election fraction 120 ms). The presence of left ventricular dys-synchrony is needed to result in improvement after cardiac resynchronization therapy. (C)2003 by Excerpta Medica, Inc.

Relationship of ventricular longitudinal function to contractile reserve in patients with mitral regurgitation

Background Latent left ventricular (LV) dysfunction in patients with valvular or myocardial disease may be identified by loss of contractile reserve (CR) at exercise echocardiography. Contraction in the LV longitudinal axis may be more sensitive than radial contraction to minor disturbances of LV function. We sought to determine whether tissue Doppler measurement of longitudinal function could be used to identify CR. Methods Exercise echocardiography was performed in 86 patients (20 women, age 53 +/- 18 years), 72 with asymptomatic or minimally symptomatic mitral regurgitation, and 14 normal controls. Pulsed-wave tissue Doppler imaging (DTI) was used to measure maximum annular systolic velocity at rest and stress. Inducible ischemia was excluded by analysis of wall motion by an experienced observer. CR was defined by greater than or equal to5% improvement of stress compared with rest ejection fraction (EF). Exercise capacity was assessed from expired gas analysis. Results CR was present in 34 patients with mitral regurgitation (47%); peak EF in patients with and without CR was 74% +/- 11% versus 54% +/- 15% (P

Usefulness of B-type natriuretic peptide in hypertensive patients with exertional dyspnea and normal left ventricular ejection fraction and correlation with new echocardiographic indexes of systolic and diastolic function

B-type natriuretic peptide (BNP) levels increase in systolic heart failure (HF). However, the value of BNP in hypertensive patients with suspected diastolic HF (symptoms suggestive of HF but normal ejection fraction) and its relation to myocardial function in these patients is unclear. We prospectively studied 72 ambulatory hypertensive subjects (40 women, mean age 58 +/- 8 years) with exertional dyspnea and ejection fraction greater than or equal to50%. Diastolic function was evaluated with transmitral and pulmonary venous Doppler, mitral annular velocities (pulsed-wave tissue Doppler), and flow propagation velocity (color M-mode). Systolic function was assessed with strain and strain rate derived from color tissue Doppler imaging. BNP was related to myocardial function and the presence or absence of global diastolic dysfunction. By conventional Doppler criteria, 34 patients had normal left ventricular diastolic function and 38 had isolated diastolic dysfunction. BNP values were higher in patients with diastolic dysfunction (46 +/- 48 vs 20 +/- 20 pg/ml, p = 0.004) and were related independently to blood pressure, systolic strain rate, left atrial function (p < 0.01 for all), and age (p = 0.015). Patients with diastolic dysfunction and pseudonormal filling had higher BNP levels compared with impaired relaxation (89 +/- 47 vs 35 +/- 42 pg/ml, p = 0.001). However, 79% of patients with diastolic dysfunction had BNP levels within the normal range. We conclude that in ambulatory hypertensive patients with symptoms suggestive of mild HF and normal ejection fraction, BNP is related to atrial and ventricular systolic parameters, blood pressure, and age. Although elevated in the presence of diastolic dysfunction, the BNP level mostly is in the normal range and, therefore, has limited diagnostic value in stable patients with suspected diastolic HF. (C) 2003 by Excerpta Medica, Inc.

Usefulness of myocardial tissue Doppler echocardiography to evaluate left ventricular dyssynchrony before and after biventricular pacing in patients with idiopathic dilated cardiomyopathy

Tissue Doppler imaging allows assessment of left ventricular dyssynchrony and resynchronization after biventricular pacing.

Usefulness of quantitative echocardiographic techniques to predict recovery of regional and global left ventricular function after acute myocardial infarction

The left ventricular response to dobutamine may be quantified using tissue Doppler measurement of myocardial velocity or displacement or 3-dimensional echocardiography to measure ventricular volume and ejection fraction. This study sought to explore the accuracy of these methods for predicting segmental and global responses to therapy. Standard dobutamine and 3-dimensional echocardiography were performed in 92 consecutive patients with abnormal left ventricular function at rest. Recovery of function was defined by comparison with follow-up echocardiography at rest 5 months later. Segments that showed improved regional function at follow-up showed a higher increment in peak tissue Doppler velocity with dobutamine therapy than in nonviable segments (1.2 +/- 0.4 vs 0.3 +/- 0.2 cm/s, p = 0.001). Similarly, patients who showed a > 5% improvement of ejection fraction at follow-up showed a greater displacement response to dobutamine (6.9 +/- 3.2 vs 2.1 +/- 2.3 mm, p = 0.001), as well as a higher rate of ejection fraction, response to dobutamine (9 +/- 3% vs 2 +/- 2%, p = 0.001). The optimal cutoff values for predicting subsequent recovery of function at rest were an increment of peak velocity > 1 cm/s, >5 mm of displacement, and a >5% improvement of ejection fraction with low-dose dobutamine. (C) 2003 by Excerpta Medica, Inc.

Ventricular dysfunction in early diabetic heart disease: detection, mechanisms and significance

The detection of preclinical heart disease is a new direction in diabetes care. This comment describes the study by Vinereanu and co-workers in this issue of Clinical Science in which tissue Doppler echocardiography has been employed to demonstrate subtle systolic and diastolic dysfunction in Type 11 diabetic patients who had normal global systolic function and were free of coronary artery disease. The aetiology of early ventricular dysfunction in diabetes relates to complex intramyocardial and extramyocardial mechanisms. The initiating event may be due to insulin resistance, and involves abnormal myocardial substrate utilization and uncoupling of mitochondrial oxidative phosphorylation. Dysglycaemia plays an important role via the effects of oxidative stress, protein kinase C activation and advanced glycosylation end-products on inflammatory signalling, collagen metabolism and fibrosis. Extramyocardial mechanisms involve peripheral endothelial dysfunction, arterial stiffening and autonomic neuropathy. The clinical significance of the ventricular abnormalities described is unknown. Confirmation of their prognostic importance for cardiac disease in diabetes would justify routine screening for presymptomatic ventricular dysfunction, as well as clinical trials of novel agents for correcting causal mechanisms. These considerations could also have implications for patients with obesity and the metabolic syndrome.

In situ characterization of stickiness of sugar-rich foods using a linear actuator driven stickiness testing device

A stickiness testing device based on the probe tack test has been designed and tested. It was used to perform in situ characterization of drying hemispherical drops with an initial radius 3.5 mm. Tests were carried out in two drying temperatures, 63 and 95 degreesC. Moisture and temperature histories of the drying drops of fructose, honey, sucrose, maltodextrin and sucrose-maltodextrin mixtures were determined. The rates of moisture evaporation of the fructose solution was the fastest while those of the maltodextrin solution was the lowest. A profile reversal was observed when the temperature profiles of these materials were compared. Different modes of failure were observed during the stickiness tests. Pure fructose and honey solutions remained completely sticky and failed cohesively until the end of drying. Pure sucrose solution remained sticky and failed cohesively until complete crystallization occurred. The surface of the maltodextrin drops formed a skin shortly after the start of drying. It exhibited adhesive failure and reached a state of non-adhesion. Addition of maltodextrin significantly altered the stickiness of sucrose solution. (C) 2002 Elsevier Science Ltd. All rights reserved.

A class B switch-mode assisted linear amplifier

A switch-mode assisted linear amplifier (SMALA) combining a linear (Class B) and a switch-mode (Class D) amplifier is presented. The usual single hysteretic controlled half-bridge current dumping stage is replaced by two parallel buck converter stages, in a parallel voltage controlled topology. These operate independently: one buck converter sources current to assist the upper Class B output device, and a complementary converter sinks current to assist the lower device. This topology lends itself to a novel control approach of a dead-band at low power levels where neither class D amplifier assists, allowing the class B amplifier to supply the load without interference, ensuring high fidelity. A 20 W implementation demonstrates 85% efficiency, with distortion below 0.08% measured across the full audio bandwidth at 15 W. The class D amplifier begins assisting at 2 W, and below this value, the distortion was below 0.03%. Complete circuitry is given, showing the simplicity of the additional class D amplifier and its corresponding control circuitry.

O censo Suas como processo de aprimoramento e institucionaliza????o da pol??tica de assist??ncia social no Brasil

O Censo Suas ?? um processo de monitoramento que coleta dados por meio de um formul??rio eletr??nico preenchido pelas secretarias e conselhos de Assist??ncia Social. ?? realizado anualmente desde 2007, por meio de uma a????o integrada entre a Secretaria de Assist??ncia Social e a Secretaria de Avalia????o e Gest??o da Informa????o. Esse processo alcan??ou sua maturidade com a incorpora????o de novos question??rios para a coleta de informa????es sobre ??rg??os gestores, Conselhos e entidades privadas de Assist??ncia Social. Em 2010, 99,2% dos munic??pios preencheram 28.519 question??rios. Assim, a Assist??ncia Social aprimorou seu processo de tomada de decis??o, expandindo a rede e a cobertura dos servi??os. Com os indicadores e as metas de desenvolvimento dos Centros de Refer??ncia de Assist??ncia Social (Cras), apurados com base no Censo, foram retroalimentados a????es e projetos de assist??ncia social, institu??dos processos gradativos de adequa????o dos servi??os ??s normas e constitu??dos processos de planejamento para melhoria da gest??o e do controle social do Sistema ??nico de Assist??ncia Social (Suas)

Rede Suas: o sistema nacional de informa????o da assist??ncia social

A Rede SUAS ?? o sistema de informa????o do Sistema ??nico de Assist??ncia Social ??? SUAS e tem a fun????o de responder ??s novas necessidades de informa????o e comunica????o no ??mbito do SUAS, que ?? a regula????o ampliada da Constitui????o Federal de 88, no que tange ?? pol??tica p??blica de assist??ncia social, integrante do sistema brasileiro de seguridade social. Considerada como um instrumento de gest??o colegiada, a Rede SUAS inaugurou para os trabalhadores, gestores e entidades da ??rea, a tarefa de redimensionar a cultura de gest??o, at?? ent??o vivenciada, com a instala????o de aplicativos que geram novos ??ndices de agilidade e transpar??ncia, dando suporte aos processos e procedimentos previstos na Pol??tica Nacional de Assist??ncia Social, 2004, PNAS e na norma operacional b??sica do SUAS/2005. O projeto resolve duas quest??es centrais para a ??rea: a revers??o das tend??ncias que caracterizaram experi??ncias anteriores de gest??o e a necess??ria associa????o dos instrumentos e condi????es tecnol??gicas de produ????o, recebimento, tratamento, armazenamento e entrega de dados e informa????o, com as opera????es de gest??o, financiamento e controle social da pol??tica p??blica de assist??ncia social

A integra????o do Programa Bolsa Fam??lia e da Assist??ncia Social: um olhar sobre a gest??o municipal do Programa

O presente trabalho tem como objetivo entender como se deu a integra????o do Programa Bolsa Fam??lia com a assist??ncia social, tendo em vista que na maior parte dos munic??pios a gest??o do PBF est?? sob a responsabilidade das Secretarias Municipais de Assist??ncia Social. Ao analisar o PBF, foi poss??vel notar duas principais caracter??sticas: 1) descentraliza????o e 2) intersetorialidade. No caso da primeira, as responsabilidades s??o descentralizadas para estados e munic??pios. A implementa????o do PBF dependeu de processos de negocia????o e coordena????o federativa, constru??das a partir de mecanismos volunt??rios de ades??o e pactua????o. J?? com rela????o ?? segunda caracter??stica, o PBF ?? um programa de transfer??ncia de renda com condicionalidades, assim, ele se articula com as ??reas de sa??de e educa????o, que fazem o acompanhamento das condicionalidades das fam??lias benefici??rias. A assist??ncia social tem participa????o nas duas caracter??sticas. Na descentraliza????o, a assist??ncia foi aos poucos incorporando a gest??o municipal do PBF. Quanto ?? integra????o na intersetorialidade do Programa, a assist??ncia social tem o papel de ofertar o acompanhamento familiar ??s fam??lias que n??o cumprem os compromissos da agenda de sa??de ou a frequ??ncia escolar, no acompanhamento das condicionalidades. Para analisar as formas como a assist??ncia social participa da gest??o do PBF foram elaboradas tipologias de estrutura de gest??o do programa. O trabalho tamb??m contou com a an??lise de quatro fontes de dados diferentes: duas quantitativas (Censo SUAS 2011 e Relat??rio de Ades??o dos Munic??pios ao PBF) e duas qualitativas (relat??rios de visitas municipais e question??rios aplicados aos gestores municipais ou t??cnicos do PBF). Com base nas tipologias e nos dados analisados, dentro da assist??ncia foram encontrados tr??s modelos diferentes: gest??o do PBF como uma unidade central no ??rg??o gestor, gest??o do PBF com equipe exclusiva no CRAS e gest??o do PBF sob responsabilidade do PAIF. A partir das pesquisas e das observa????es, foi poss??vel identificar que em 93% dos munic??pios a gest??o do PBF est?? como responsabilidade do ??rg??o gestor da assist??ncia, nos demais a gest??o ?? responsabilidade do gabinete do prefeito ou de outras ??reas, como sa??de, educa????o, finan??as, administra????o ou outras. O trabalho localizou ainda quatro espa??os onde a assist??ncia social participa da gest??o do PBF de forma integrada: 1) Cadastro ??nico, 2) transfer??ncia fundo a fundo para o IGD, 3) Protocolo de Gest??o Integrada de Servi??os Benef??cios e Transfer??ncia de Renda no ??mbito do SUAS, e seus desdobramentos, e 4) presen??a do PBF nas Comiss??es, F??runs e Conselhos de Assist??ncia Social. Ao final, constatou-se que as fontes utilizadas na pesquisa n??o detalham como ?? a participa????o da assist??ncia na gest??o do PBF. Tendo em vista que na maior parte dos munic??pios a assist??ncia ?? a respons??vel pela gest??o do Programa, as considera????es finais trazem a recomenda????o de o Censo SUAS ser o instrumento que pode fornecer insumos para avalia????o de gest??o do PBF, facilitando o planejamento de a????es e di??logos com as equipes municipais