Estimativas nacionais e internacionais indicam que a síndrome coronariana aguda é uma das principais causas de internação hospitalar e óbito. A maioria desses pacientes tem diagnóstico de síndrome coronariana aguda sem supradesnivelamento do segmento ST (SCASSSST) e possui amplo espectro de gravidade, que varia de acordo com características clínicas e laboratoriais. A estratificação de risco é essencial para auxiliar na decisão clínica, discriminando quais pacientes se beneficiam de estratégias mais agressivas. Os escores TIMI e GRACE são os mais utilizados e com valor prognóstico estabelecido por estudos de coorte prospectiva. O strain longitudinal bidimensional (S2DL) permite a quantificação da deformidade miocárdica por meio do rastreamento de \"marcas acústicas\" naturais do músculo cardíaco pelo ultrassom, apresentando valores reduzidos na presença de isquemia miocárdica. O objetivo principal desse trabalho foi identificar, por meio do S2DL do ventrículo esquerdo, quais pacientes com SCASSSST apresentam estenose coronariana maior ou igual a 70%. Os objetivos secundários foram: 1) Identificar a porcentagem de pacientes categorizados como de baixo risco e moderado risco, segundo os escores TIMI e GRACE, que apresentaram estenose coronária maior ou igual a 70%; 2) Determinar um valor de corte do S2DL e número mínimo de segmentos adjacentes acometidos que se correlacionem com o território irrigado pela coronária comprometida (com estenose maior ou igual a 70%) nos pacientes portadores de SCASSSST. Total de 100 pacientes com Idade de 60±11,4, 62% do sexo masculino e predomínio de pacientes (p) de baixo e moderado risco cardiovascular (80% pelo escore TIMI e 99% pelo escore GRACE). Divididos em grupo A (34p) com estenose coronária < 70% e grupo B (66p) com estenose coronária >=70%. Os escores clínicos foram maiores no grupo B (TIMI 3,59±1,4; p=0,008 e GRACE 88,7±24,18; p=0,040). O strain longitudinal global (SLG) permitiu identificar os pacientes com estenose coronária >=70% (AUC=0,72, sensibilidade=50%, especificidade=90%, valor preditivo positivo= 75,1% e valor preditivo negativo=74,9%). No grupo B, 72,8% e 98,5% foram categorizados como de baixo e moderado risco pelos escores TIMI e GRACE, respectivamente. O strain longitudinal segmentar (SLS) permitiu identificar a coronária culpada pelo evento isquêmico, com valor de cut-off e número mínimo de segmentos estimados em: -14 e 4 segmentos para coronária descendente anterior, -16 e 3 segmentos para a coronária circunflexa e coronária direita. Concluímos que o SLG mostrou ser acurado em discriminar pacientes com estenose coronária grave, mesmo naqueles com escore de risco baixo e moderado pelos escores TIMI e GRACE. O SLS permite estimar a área de miocárdio isquêmico por meio do número de segmentos com deformidade alterada, e conhecer a coronária culpada mais provável. / National and international estimates indicate that acute coronary syndrome is one of the major causes of hospitalization and death. Most of these patients have a diagnosis of non-ST-elevation acute coronary syndrome (NSTE-ACS) and have wide spectrum of severity. Risk stratification is essential to assist in clinical decision. The TIMI and GRACE risk scores are the most used and the prognostic values were established by prospective cohort study. Myocardial strain by speckle tracking is a technique based on widely available two-dimensional grayscale echocardiography, enabling the accurate evaluation of global and regional myocardial function, and it is has been shown to be sensitive to abnormalities caused by ischemia. The main objective of this study was to identify, through global longitudinal strain, whose patients (p) with NSTE-ACS had >= 70 % coronary stenosis. The secondary objectives were: 1) Identify the percentage of p categorized as low or moderate risk according to the TIMI and GRACE risk scores , who showed coronary stenosis >= 70 % ; 2) Determine a cutoff value of regional strain and the minimum number of segments allowing the identification of the culprit coronary artery in p with NSTE-ACS. Hundred (p) with diagnosis NSTE-ACS were stratified according to TIMI and GRACE risk scores, and all p underwent coronary angiography. Global longitudinal strain (GLS) and territorial strain (TS) were calculated. Age 60 ± 11.4, 62% male. Majority were low and moderate cardiovascular risk (TIMI score by 80 % and 99 % by the GRACE score). They were divided into group A (34p) with coronary stenosis < 70 % and group B (66p) with coronary stenosis >= 70 %. Clinical scores were higher in group B (TIMI 3.59 ± 1.4, p = 0.008 and 88.7 ± GRACE 24.18, p = 0.040). SLG was accurate identifying p with coronary stenosis >= 70 % (AUC = 0.72, p=0.001, sensitivity = 50 %, specificity = 90 %, positive predictive value = 75.1 % and negative predictive value = 74.9 %). Group B were low and moderate cardiovascular risk 72.8 % by TIMI risk score and 98.5 % by GRACE risk scores. TS was able to identify the culprit coronary in an ischemic event with cutoff values and minimum number of damaged segments as follow: -14 and 4 segments for anterior descending coronary, -16 and 3 segments to the circumflex coronary and right coronary. SLG has proved accurate in discriminating patients with severe coronary stenosis, even in those with low and moderate risk by TIMI and GRACE risk scores. TS estimates the area of ischemic myocardium by the number of segments with abnormal deformity, and suggests the most likely culprit coronary.

<p>Positron Emission Tomography (PET) permits regional myocardial perfusion, fibrosis and oxidative metabolism to be non-invasively quantified with radioactive tracers such as [¹⁵O]-water and [1-¹¹C]-acetate. PET is an established research tool in congestive heart failure (CHF), a major cause of morbidity and mortality. However, as CHF is a syndrome that eventually affects all aspects of cardiac and systemic hemodynamic function, more clinically relevant information from a single PET scan is desirable. The aim of this thesis therefore was to develop and implement some new concepts in cardiac PET.</p><p>A new method for the measurement of cardiac output with any tracer was validated in animal experiments and CHF patients. The early pulmonary retention of [1-¹¹C]-acetate was inversely related to left ventricular (LV) function in animals and was directly proportional to lung water content and severity of LV diastolic dysfunction in patients.</p><p>Eight patients with acute myocardial infarction were followed with serial PET from 3 hours to 3 weeks after trombolytic treatment. PET revealed that myocardial perfusion and the extraction and utilization of fuel substrates all decreased closer to the infarct centre. The rate of oxygen utilization within the infarct at 3 h predicted degree of myocardial fibrosis, pulmonary oedema and tissue viability at 3 weeks. </p><p>Seventeen patients with CHF due to chronic ischemic cardiomyopathy and severely reduced LV function were evaluated with [1-¹¹C]-acetate PET before and after coronary artery bypass surgery. There was a dramatic improvement in physical performance and symptoms, which was not correlated to the standard LV ejection indices. PET revealed that functional improvement was associated with improved LV loading conditions, reversed remodeling and homogenization of oxidative metabolism rather than increased output.</p>

Positron Emission Tomography (PET) permits regional myocardial perfusion, fibrosis and oxidative metabolism to be non-invasively quantified with radioactive tracers such as [15O]-water and [1-11C]-acetate. PET is an established research tool in congestive heart failure (CHF), a major cause of morbidity and mortality. However, as CHF is a syndrome that eventually affects all aspects of cardiac and systemic hemodynamic function, more clinically relevant information from a single PET scan is desirable. The aim of this thesis therefore was to develop and implement some new concepts in cardiac PET. A new method for the measurement of cardiac output with any tracer was validated in animal experiments and CHF patients. The early pulmonary retention of [1-11C]-acetate was inversely related to left ventricular (LV) function in animals and was directly proportional to lung water content and severity of LV diastolic dysfunction in patients. Eight patients with acute myocardial infarction were followed with serial PET from 3 hours to 3 weeks after trombolytic treatment. PET revealed that myocardial perfusion and the extraction and utilization of fuel substrates all decreased closer to the infarct centre. The rate of oxygen utilization within the infarct at 3 h predicted degree of myocardial fibrosis, pulmonary oedema and tissue viability at 3 weeks. Seventeen patients with CHF due to chronic ischemic cardiomyopathy and severely reduced LV function were evaluated with [1-11C]-acetate PET before and after coronary artery bypass surgery. There was a dramatic improvement in physical performance and symptoms, which was not correlated to the standard LV ejection indices. PET revealed that functional improvement was associated with improved LV loading conditions, reversed remodeling and homogenization of oxidative metabolism rather than increased output.

Patients with chronic kidney disease are at higher risk of developing cardiovascular disease. The complex, interaction between the kidney and the cardiovascular system is incompletely understood, particularly at the early stages of the cardiovascular continuum. The overall aim of this thesis was to clarify novel aspects of the interplay between the kidney and the cardiovascular system at different stages of the cardiovascular continuum; from risk factors such as insulin resistance, inflammation and oxidative stress, via sub-clinical cardiovascular damage such as endothelial dysfunction and left ventricular dysfunction, to overt cardiovascular death. This thesis is based on two community-based cohorts of elderly, Uppsala Longitudinal Study of Adult Men (ULSAM) and Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS). The first study, show that higher insulin sensitivity, measured with euglycemic-hyperinsulinemic clamp technique was associated to improve estimated glomerular filtration rate (eGFR) in participants with normal fasting plasma glucose, normal glucose tolerance and normal eGFR. In longitudinal analyses, higher insulin sensitivity at baseline was associated with lower risk of impaired renal function during follow-up. In the second study, eGFR was inversely associated with different inflammatory markers (C-reactive protein, interleukin-6, serum amyloid A) and positively associated with a marker of oxidative stress (urinary F2-isoprostanes). In line with this, the urinary albumin/creatinine ratio was positively associated with these inflammatory markers, and negatively associated with oxidative stress. In study three, higher eGFR was associated with better endothelial function as assessed by the invasive forearm model. Further, in study four, higher eGFR was significantly associated with higher left ventricular systolic function (ejection fraction). The 5th study of the thesis shows that higher urinary albumin excretion rate (UAER) and lower eGFR was independently associated with an increased risk for cardiovascular mortality. Analyses of global model fit, discrimination, calibration, and reclassification suggest that UAER and eGFR add relevant prognostic information beyond established cardiovascular risk factors in participants without prevalent cardiovascular disease. Conclusion: this thesis show that the interaction between the kidney and the cardiovascular system plays an important role in the development of cardiovascular disease and that this interplay begins at an early asymptomatic stage of the disease process.

The scientific novelty of the study A large number of reports have demonstrated that depressed heart rate variability after myocardial infarction (MI), left ventricular dysfunction and arrhythmias are powerful predictors of mortality. Nevertheless there is a lack of detailed assessment of heart rate variability in the acute period of MI, especially during the first 24 hours, from long-term (24-h) recordings, and the value of different parameters of heart rate variability in predicting dangerous complications of MI was not fully evaluated. The indications of complex and constant monitoring of heart rate variability, left ventricular function, arrhythmias in acute MI are not based on scientific studies as well as their value in predicting the effect of different methods of management, course and outcomes of critical cardiac conditions. Thus, the current study differs from all the earlier studies in that we assessed heart rate variability in the very early period of myocardial infarction (the first and the third day) using long time recordings (24 h), both – time-domain and frequency-domain –methods, and evaluated its changes in relation to arrhythmias and left ventricular function, using not only conventional 2D-echocardiography but also left ventricular long axis function assessment by M-mode and tissue Doppler imaging. The aim of the study The aim of the study was to determine the association between heart rate variability, cardiac arrhythmias and left ventricular... [to full text]

Orientador: Meliza Goi Roscani / Resumo: Os efeitos favoráveis de um programa de exercício físico combinado (EFC) em pacientes com insuficiência cardíaca (IC) e fração de ejeção ventricular esquerda reduzida (FEVER) são bem reconhecidos na literatura. Acredita-se que os efeitos benéficos do EF não se devam à melhora da FEVE. Por outro lado, alguns estudos apontaram para efeitos benéficos do EF na função diastólica do VE. Tendo em vista a importância da pressão de enchimento do VE na sintomatologia dos pacientes com IC, levantou-se a hipótese de que de que um programa de EFC e supervisionado é capaz de promover melhora na função diastólica em pacientes com IC com FEVE < 50%, e que esse efeito está associado à diminuição dos sintomas, refletindo em melhora da CF e da QV nesses pacientes. Objetivos: avaliar o efeito do EFC na função diastólica de pacientes com IC de FEVE reduzida e investigar se a melhora na função diastólica é fator associado à melhora dos sintomas, capacidade funcional e qualidade de vida desses pacientes. Metodologia: trata-se de um ensaio clínico prospectivo, randomizado e controlado, que incluiu pacientes com IC e FEVE <50%, acima de 18 anos. A amostra foi composta por 42 pacientes, distribuídos em 2 grupos pareados por idade e sexo: grupo controle (GC) n=20 - submetidos à prescrição já realizada nas consultas de rotina para prática de atividade física regular não supervisionada. Grupo intervenção (GI) n=22 - submetidos a um programa de exercício físico supervisionado composto por exercício aerób... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The favorable effects of a combined exercise program (CEP) in patients with heart failure (HF) and reduced left ventricular ejection fraction (RLVE) are well recognized in the literature. There is consensus that physical exercise (PE) improves quality of life (QOL) and functional capacity (FC) in patients with HF. It is believed that the beneficial effects of PE are not due to the improvement of LVEF. On the other hand, some studies indicated beneficial effects of PE on LV diastolic function. Given the importance of LV filling pressure in symptoms of HF patients, the hypothesis of this study was that an CEP supervised program should promote improvement in diastolic function in patients with HF with LVEF <50% and this effect may be associated with decreased symptoms, reflecting improvement in FC and QOL in these patients. Objective: evaluate the effect of ECF in diastolic function in patients with reduced LVEF IC and investigate whether the improvement in diastolic function is r associated with improvement in symptoms, functional capacity and quality of life of these patients. Methodology: Prospective clinical trial, randomized and controlled, which included patients with HF and LVEF <50%, above 18 years. The sample consisted of 42 patients, divided into two groups matched for age and sex: the control group (CG) n = 20 - submitted to prescription in clinical practice of regular physical activity, not supervised. Intervention group (IG) n = 22 - underwent a physical exercise pr... (Complete abstract click electronic access below) / Mestre

Estimativas nacionais e internacionais indicam que a síndrome coronariana aguda é uma das principais causas de internação hospitalar e óbito. A maioria desses pacientes tem diagnóstico de síndrome coronariana aguda sem supradesnivelamento do segmento ST (SCASSSST) e possui amplo espectro de gravidade, que varia de acordo com características clínicas e laboratoriais. A estratificação de risco é essencial para auxiliar na decisão clínica, discriminando quais pacientes se beneficiam de estratégias mais agressivas. Os escores TIMI e GRACE são os mais utilizados e com valor prognóstico estabelecido por estudos de coorte prospectiva. O strain longitudinal bidimensional (S2DL) permite a quantificação da deformidade miocárdica por meio do rastreamento de \"marcas acústicas\" naturais do músculo cardíaco pelo ultrassom, apresentando valores reduzidos na presença de isquemia miocárdica. O objetivo principal desse trabalho foi identificar, por meio do S2DL do ventrículo esquerdo, quais pacientes com SCASSSST apresentam estenose coronariana maior ou igual a 70%. Os objetivos secundários foram: 1) Identificar a porcentagem de pacientes categorizados como de baixo risco e moderado risco, segundo os escores TIMI e GRACE, que apresentaram estenose coronária maior ou igual a 70%; 2) Determinar um valor de corte do S2DL e número mínimo de segmentos adjacentes acometidos que se correlacionem com o território irrigado pela coronária comprometida (com estenose maior ou igual a 70%) nos pacientes portadores de SCASSSST. Total de 100 pacientes com Idade de 60±11,4, 62% do sexo masculino e predomínio de pacientes (p) de baixo e moderado risco cardiovascular (80% pelo escore TIMI e 99% pelo escore GRACE). Divididos em grupo A (34p) com estenose coronária < 70% e grupo B (66p) com estenose coronária >=70%. Os escores clínicos foram maiores no grupo B (TIMI 3,59±1,4; p=0,008 e GRACE 88,7±24,18; p=0,040). O strain longitudinal global (SLG) permitiu identificar os pacientes com estenose coronária >=70% (AUC=0,72, sensibilidade=50%, especificidade=90%, valor preditivo positivo= 75,1% e valor preditivo negativo=74,9%). No grupo B, 72,8% e 98,5% foram categorizados como de baixo e moderado risco pelos escores TIMI e GRACE, respectivamente. O strain longitudinal segmentar (SLS) permitiu identificar a coronária culpada pelo evento isquêmico, com valor de cut-off e número mínimo de segmentos estimados em: -14 e 4 segmentos para coronária descendente anterior, -16 e 3 segmentos para a coronária circunflexa e coronária direita. Concluímos que o SLG mostrou ser acurado em discriminar pacientes com estenose coronária grave, mesmo naqueles com escore de risco baixo e moderado pelos escores TIMI e GRACE. O SLS permite estimar a área de miocárdio isquêmico por meio do número de segmentos com deformidade alterada, e conhecer a coronária culpada mais provável. / National and international estimates indicate that acute coronary syndrome is one of the major causes of hospitalization and death. Most of these patients have a diagnosis of non-ST-elevation acute coronary syndrome (NSTE-ACS) and have wide spectrum of severity. Risk stratification is essential to assist in clinical decision. The TIMI and GRACE risk scores are the most used and the prognostic values were established by prospective cohort study. Myocardial strain by speckle tracking is a technique based on widely available two-dimensional grayscale echocardiography, enabling the accurate evaluation of global and regional myocardial function, and it is has been shown to be sensitive to abnormalities caused by ischemia. The main objective of this study was to identify, through global longitudinal strain, whose patients (p) with NSTE-ACS had >= 70 % coronary stenosis. The secondary objectives were: 1) Identify the percentage of p categorized as low or moderate risk according to the TIMI and GRACE risk scores , who showed coronary stenosis >= 70 % ; 2) Determine a cutoff value of regional strain and the minimum number of segments allowing the identification of the culprit coronary artery in p with NSTE-ACS. Hundred (p) with diagnosis NSTE-ACS were stratified according to TIMI and GRACE risk scores, and all p underwent coronary angiography. Global longitudinal strain (GLS) and territorial strain (TS) were calculated. Age 60 ± 11.4, 62% male. Majority were low and moderate cardiovascular risk (TIMI score by 80 % and 99 % by the GRACE score). They were divided into group A (34p) with coronary stenosis < 70 % and group B (66p) with coronary stenosis >= 70 %. Clinical scores were higher in group B (TIMI 3.59 ± 1.4, p = 0.008 and 88.7 ± GRACE 24.18, p = 0.040). SLG was accurate identifying p with coronary stenosis >= 70 % (AUC = 0.72, p=0.001, sensitivity = 50 %, specificity = 90 %, positive predictive value = 75.1 % and negative predictive value = 74.9 %). Group B were low and moderate cardiovascular risk 72.8 % by TIMI risk score and 98.5 % by GRACE risk scores. TS was able to identify the culprit coronary in an ischemic event with cutoff values and minimum number of damaged segments as follow: -14 and 4 segments for anterior descending coronary, -16 and 3 segments to the circumflex coronary and right coronary. SLG has proved accurate in discriminating patients with severe coronary stenosis, even in those with low and moderate risk by TIMI and GRACE risk scores. TS estimates the area of ischemic myocardium by the number of segments with abnormal deformity, and suggests the most likely culprit coronary.

Phenylethanolamine-N-methyltransferase (Pnmt) catalyzes the conversion of noradrenaline to adrenaline and is the last enzyme in the catecholamine biosynthetic pathway. Pnmt serves as a marker for adrenergic cells, and lineage-tracing experiments have identified the embryonic heart and hindbrain region as the first sites of Pnmt expression in the mouse. Pnmt expression in the heart occurs before the adrenal glands have formed and prior to sympathetic innervation, suggesting that the heart is the first site of catecholamine production in the mouse. The function of these Pnmt+ cells in heart development remains unclear. In the present study, we test the hypothesis that (i) a genetic ablation technique utilizing a suicide reporter gene selectively destroys Pnmt cells in the mouse, and (ii) Pnmt cells are required for normal cardiovascular and neurological function. To genetically ablate adrenergic cells, we mated Pnmt-Cre mice, in which Cre-recombinase is under the transcriptional regulation of the Pnmt promoter, and a Cre -activated diphtheria toxin A (DTA) mouse strain (ROSA26-eGFP-DTA), thereby causing activation of the toxic allele (DTA) in Pnmt-expressing (adrenergic) cells resulting in selective "suicide" of these cells in approximately half of the offspring. The other half serve as controls because they do not have the ROSA26-eGFP-DTA construct. In the Pnmt+/Cre; R26+/DTA offspring, we achieve a dramatic reduction in Pnmt transcript and Pnmt immunoreactive area in the adrenal glands. Furthermore, we show that loss of Pnmt cells results in severe left ventricular dysfunction that progressively worsens with age. These mice exhibit severely reduced cardiac output and ejection fraction due to decreased LV contractility and bradycardia at rest. Surprisingly, these mice appear to have a normal stress response, as heart rate and ejection fraction increased to a similar extent compared to controls. In addition to baseline cardiac dysfunction, these mice fail to gain body weight in a normal manner and display gross neurological dysfunction, including muscular weakness, abnormal gaiting, and altered tail suspension reflex, an indicator of neurological function. This work demonstrates that selective Pnmt cell destruction leads to severe left ventricular dysfunction, lack of weight gain, and neurological dysfunction. This novel mouse is expected to shed insight into the role of Pnmt cells in the heart, and suggests a role for Pnmt cells in neurological regulation of feeding behavior, metabolism, and motor control.

Introdução: Nos pacientes coronarianos, portadores de disfunção ventricular esquerda (DVE), a mortalidade cirúrgica da revascularização miocárdica é 3 a 4 vezes maior do que a encontrada em pacientes com função ventricular normal, sendo fundamental a seleção daqueles que efetivamente poderão ser beneficiados pela cirurgia. As metanálises indicam que a pesquisa da viabilidade miocárdica é útil nesta seleção, impactando em melhora da contratilidade ventricular e redução de mortalidade quando a revascularização é realizada em pacientes com ventrículo esquerdo viável; entretanto, os estudos clínicos randomizados não encontraram os mesmos resultados. Isso porque, apesar de 50% desses pacientes apresentarem quantidades substanciais de viabilidade miocárdica, nem todos conseguem melhorar a contratilidade ventricular esquerda após a revascularização, devido à existência de outros fatores que interferem nessa melhora. Objetivos: Determinar os fatores preditores de melhora da contratilidade ventricular esquerda em pacientes com fração de ejeção < 50% submetidos à cirurgia de revascularização miocárdica (CRM) isolada e o tempo necessário para a ocorrência dessa melhora contrátil. Métodos: Estudo prospectivo observacional que avaliou pacientes coronarianos com DVE submetidos a eletrocardiograma e ecocardiograma no pré-operatório e 1, 3, 6, 9 e 12 meses após a CRM, e à ressonância magnética cardíaca (RMC) com estresse farmacológico com dipiridamol e realce tardio com gadolínio no pré-operatório e após 3 e 12 meses da revascularização, buscando associações entre a melhora da contratilidade ventricular esquerda e as diversas variáveis dos pacientes. Resultados: Foram estudados 306 segmentos miocárdicos de 18 pacientes, com idade de 59,5 + 7,4 anos. Ocorreu melhora contrátil em 47 (29%) segmentos do ventrículo esquerdo que apresentavam alterações contráteis pré-operatórias (p < 0,0001). A análise multivariada identificou três fatores preditores de melhora da contratilidade ventricular esquerda: a ausência de onda Q patológica, que aumenta em 172% a chance de melhora, a presença de viabilidade miocárdica, que aumenta em 282% a chance de melhora e a ausência de isquemia miocárdica, que aumenta em 392% a chance de melhora (razão de chances 2,72, IC 95%, 1,24 a 5,92, p = 0,012; razão de chances 3,82, IC 95%, 1,79 a 8,16, p = 0,0005; e razão de chances 4,92, IC 95%, 2,13 a 11,36, p = 0,0002, respectivamente). Em 9 (75%) pacientes a melhora da contratilidade ventricular ocorreu nos 3 primeiros meses após a CRM e em 3 (25%) pacientes ocorreu nos 9 meses seguintes Conclusões: Os três fatores preditores de melhora da contratilidade ventricular esquerda encontrados foram a ausência de onda Q patológica no eletrocardiograma, e a presença de viabilidade e ausência de isquemia miocárdicas na RMC. A recuperação da contratilidade ventricular esquerda ocorreu predominantemente nos 3 primeiros meses após a CRM, no entanto foi verificada uma melhora progressiva até o final dos 12 meses de seguimento. / Introduction: In patients with coronary artery disease (CAD) and left ventricular dysfunction, the surgical mortality from coronary artery bypass graft (CABG) is 3 to 4 times higher than that reported for patients with normal ventricular function, and selecting those who can effectively benefit from the surgery is essential. Meta-analyses have indicate that myocardial viability assessment is useful in this selection, impacting on left ventricular contractility improvement and mortality reduction when revascularization is performed in patients with viable left ventricles; However, randomized clinical trials have not found the same results. Although 50% of these patients have substantial myocardial viability, not all of them can improve left ventricular contractility after revascularization, due to other factors that interfere with this improvement. Objectives: This study aims to determine the predictors of improvement in left ventricular contractility in patients with an ejection fraction of <50% who underwent isolated CABG, as well as the time required for this improvement in contractility. Methods: This prospective observational study assessed patients with CAD and left ventricular dysfunction who underwent electrocardiography and echocardiography during the preoperative period and 1, 3, 6, 9, and 12 months after CABG and cardiac magnetic resonance with pharmacological stress with dipyridamole and late gadolinium enhancement in the preoperative period and 3 and 12 months after revascularization, to determine the associations between the evolution of left ventricular contractility and several patient-related variables. Results: A total of 306 myocardial segments of the 18 patients, aged 59.5 ± 7.4 years, were studied. There was a contractile improvement in 47 (29%) segments of the left ventricle that presented preoperative contractile abnormalities (p < 0.0001). The multivariate analysis identified three predictors of left ventricular contractility improvement: the absence of pathological Q waves, which increases the chance of improvement by 172% (odds ratio (OR) 2.72, 95% confidence interval (CI), 1.24-5.92, p = 0.012), the presence of myocardial viability, which increases the chance of improvement by 282% (OR 3.82, 95% CI, 1.79-8.16, p = 0.0005), and the absence of myocardial ischemia, which increases the chances of improvement by 392%, (OR 4.92, 95% CI, 2.13-11.36, p = 0.0002). In 9 (75%) patients the improvement in ventricular contractility occurred in the first 3 months after CABG, and in 3 (25%) patients, it occurred in the following 9 months. Conclusions: The three predictors of left ventricular contractility improvement were the absence of pathological Q waves on an electrocardiogram, the presence of myocardial viability and the absence of signs of ischemia on cardiac MRI. The improvement in left ventricular contractility occurred predominantly in the first three months after CABG, but a progressive recovery was observed until the end of the 12-month follow-up period.

Introdução: A doença falciforme (DF) é a afecção hematológica hereditária de maior prevalência no mundo, sendo que a anemia falciforme (AF) é a forma mais grave com elevada morbidade e mortalidade. Alterações cardíacas são reconhecidamente associadas à AF, como aumento cavitário, hipertensão arterial pulmonar e disfunção diastólica do ventrículo esquerdo. No entanto, ainda não existe consenso quanto à função sistólica ventricular nesses pacientes. O objetivo deste estudo foi o de investigar a função ventricular de pacientes com anemia falciforme utilizando o strain e o twist ventricular obtidos pelo speckle tracking bidimensional, e reconhecer os indivíduos sob maior risco cardiovascular, em que a instituição precoce de tratamento específico poderá beneficiar essa população. Métodos: Foram recrutados 40 pacientes com anemia falciforme (23,5 ± 9,3 anos; 24 homens) e 40 controles saudáveis pareados por sexo e idade, submetidos à entrevista estruturada, ecocardiograma transtorácico, cintilografia pulmonar ventilação perfusão e coleta de amostras de sangue. Todos os indivíduos foram submetidos à avaliação ecocardiográfica convencional padrão e subsequente avaliação offline do strain sistólico biventricular e estudo rotacional do ventrículo esquerdo utilizando speckle-tracking ecocardiográfico. Resultados: Os pacientes com AF apresentaram volume do VE indexado, massa do VE indexado, pressão arterial pulmonar e E/E\' médio superiores aos controles. As medidas de FE do VE, excursão sistólica do plano da tricúspide (TAPSE), Strain Global do VE (longitudinal, circunferencial, radial) e Strain Global do VD (longitudinal) não evidenciaram diferenças entre os grupos. Twist VE se mostrou reduzido em comparação aos controles (7,4 ± 1,2? vs 10,7 ± 1,8? , P <0,0001 ) e Tempo de pico de rotação apical prolongado (366,7 ± 26,1ms vs 344,6 ± 11,7ms , P <0,0001 ). Algumas variáveis se mostraram fortemente relacionadas ao twist VE, como índice de gravidade clínico (Rho= - 0,97, Z value= - 6,05, P < 0,0001), relação E/E\' médio (r = 0,94, F valor= 156.9, p<0,0001), IVDFVE (índice do volume diastólico final do ventrículo esquerdo)(r = 0,81 e p<0,0001) e pressão sistólica arterial pulmonar (r = 0,72 e p<0,0001). Conclusões: Os resultados deste trabalho indicam que o twist ventricular esquerdo derivado do speckle tracking bidimensional encontra-se alterado em pacientes com anemia falciforme e função sistólica ventricular preservada, avaliada pela metodologia convencional, e existe forte correlação entre o twist ventricular esquerdo e o índice clínico de gravidade, relação E/E\', índice do volume diastólico final do ventrículo esquerdo e pressão sistólica arterial pulmonar. / Background: Sickle cell disease (SCD) is the most prevalent hematological condition in the world, with sickle cell anemia (SCA) being its most serious form, displaying a high level of morbidity and mortality. Cardiac changes are known to be associated with SCA, including an increase in cardiac chamber size, pulmonary hypertension and left ventricle diastolic dysfunction. However, there is still no consensus regarding the ventricular systolic function in these patients. The purpose of this study is to investigate the ventricular function of patients with sickle cell anemia utilizing the strain and ventricular twist, obtained by two-dimensional speckle tracking, as well as to identify individuals with higher cardiovascular risk, in which early application of specific treatment could benefit this group of people. Methods: 40 patients were recruited with sickle cell anemia (ages 23.5 ± 9.3 years; 24 males) and 40 healthy control individuals paired by gender and age, submitted to structured interviews, transthoracic echocardiogram, pulmonary scintigraphy and collection of blood samples. All individuals were submitted to a standard echocardiographic evaluation and subsequent off line evaluation of the biventricular systolic strain and rotational study of the left ventricle using echocardiographic speckle-tracking. Results: Patients with SCA presented LV volume indices, LV mass Indices, pulmonary arterial pressure and E/ E\' ratios statistically higher than the control individuals. Measurements of Ejection Fraction (EF) of the left ventricle, tricuspid annular plane systolic excursion (TAPSE), Overall LV Strain (Longitudinal, Circumferential, and Radial) and Overall RV Strain (Longitudinal) did not present differences between the groups. LV twist was significantly lower in relation to the control group (7,4 ± 1,2? vs 10,7 ± 1,8? , P <0,0001 ) and prolonged time to peak apical rotation (366.7 ± 26.1ms vs 344.6 ± 11.7ms , P <0.0001 ). In addition, some variables showed themselves to be strongly related to LV twist such as the clinical severity index ( Rho= - 0.97, Z value= - 6.05, P < 0.0001), E/E\' Ratio (r = 0.94, F value=156.9 e p<0.0001) ), left ventricle end diastolic volume index (LVEDV index) (r = 0,81, p<0,0001) and pulmonary systolic arterial pressure (r = 0.72 e p<0.0001). Conclusions: The results of this study indicate that the left ventricular twist derived from two-dimensional speckle tracking is altered in patients with sickle cell anemia and a preserved ventricular systolic function, evaluated using conventional methodology and that there is a strong correlation between left ventricular twist and the clinical severity index, E/E\' ratio, left ventricle end diastolic volume index and the pulmonary systolic arterial pressure.