Importancia de la sincronía aurículo-ventricular para el gasto cardíaco en un paciente con insuficiencia cardíaca y fracción de eyección reducida / Importance of atrioventricular synchrony for cardiac output in a patient with heart failure and reduced ejection fraction

RESUMEN Hombre de 80 años de edad, con antecedentes de miocardiopatía dilatada de origen isquémico, con disfunción sisto-diastólica del ventrículo izquierdo, que inicialmente presentó flutter auricular con inestabilidad hemodinámica y se realizó cardioversión eléctrica, luego de la cual se obtuvo un ritmo no precedido de onda P a 40 latidos por minuto, que fue interpretado como fibrilación auricular bloqueada; razón por la que se le colocó un marcapasos externo. Durante su evolución se realizó electrocardiograma de 12 derivaciones, donde se evidenció estimulación ventricular permanente con conducción retrógrada (ventrículo-auricular). Se disminuyó la frecuencia de estimulación para priorizar el ritmo espontáneo del paciente y se obtuvo marcada mejoría de la curva de presión arterial.

ABSTRACT An 80-year-old male patient is presented, with previous dilated cardiomyopathy of ischemic etiology, with systo-diastolic left ventricular dysfunction, who initially presented atrial flutter and hemodynamic instability, thus, an electrical cardioversion was performed. After this procedure, a blocked atrial fibrillation was observed. Thus, an external pacemaker was placed. During the evolution, a 12 lead electrocardiogram was performed, showing permanent ventricular stimulation with retrograde conduction (ventriculo-atrial). The pacing rate was diminished for prioritizing the patient's spontaneous rhythm resulting in an improvement of the blood pressure curve.

Função atrial esquerda pelo método de speckle tracking: além da avaliação volumétrica / Left atrial function using speckle tracking: beyond volumetric evaluation

Atualmente, a avaliação da função atrial esquerda é um método emergente que pode ter relação com o prognóstico dos pacientes. Classicamente, as medidas estáticas de diâmetro, área e volume são as mais usadas com esta finalidade. A técnica conhecida como speckle tracking é capaz de fornecer informações dinâmicas do átrio esquerdo ao longo do ciclo cardíaco, assim como detectar alterações na função atrial esquerda em fases subclínicas, antes de ocorrerem aumentos volumétricos ou disfunções diastólicas. Valores de normalidade para o speckle tracking estão sendo propostos, mas as diferenças metodológicas e de técnicas empregadas dificultam sua padronização. Esta revisão da literatura se propõe a discutir os avanços na análise da função atrial esquerda, em especial via speckle tracking

Assessment of Subclinical Cardiac Alterations and Atrial Electromechanical Delay by Tissue Doppler Echocardiography in Patients with Nonfunctioning Adrenal Incidentaloma / Avaliação de Alterações Cardíacas Subclínicas e Atraso Eletromecânico Atrial por Ecocardiografia com Doppler Tecidual em Pacientes com Incidentaloma Adrenal Não Funcionante

Abstract Background: Majority of the incidentally discovered adrenal masses, called adrenal incidentaloma (AI), are nonfunctioning adrenal adenomas. The appropriate management of AI is still a matter debate, so it is necessary to investigate their associated morbidity. However, data regarding morphological and functional cardiac alterations are limited in this group. Objective: In this study, we aimed to assess cardiac structural and functional characteristics and atrial conduction properties in patients with nonfunctioning AI. Methods: Thirty patients with nonfunctioning AI and 46 properly matched control subjects were included in the study. After hormonal and biochemical analysis, all participants underwent transthoracic echocardiography to obtain systolic and diastolic parameters of both ventricles, in addition to atrial conduction times by tissue Doppler echocardiography. Data were analyzed with Statistical Package for the Social Sciences (SPSS, Chicago, IL, United States) statistics, version 17.0 for Windows. P < 0.05 was considered statistically significant. Results: Left ventricular (LV) mass index and LV myocardial performance index were significantly increased in AI group. Among atrial conduction times, both intra- and interatrial electromechanical delays were significantly prolonged in patients with nonfunctioning AI. Other laboratory and echocardiographic findings were similar between groups. Conclusion: Our study revealed that intra- and inter-atrial conduction times were prolonged, and LV mass index was increased in patients with nonfunctioning AI. These findings may be markers of subclinical cardiac involvement and tendency to cardiovascular complications. Close follow-up is necessary for individuals with nonfunctioning AI for their increased cardiovascular risk.

Resumo Fundamento: A maioria das massas adrenais descobertas incidentalmente, denominadas incidentaloma adrenal (IA), são adenomas adrenais não funcionantes. O manejo adequado da IA ainda é um tema de debate, e por isso é necessário investigar suas morbidades associadas. Entretanto, dados referentes a alterações cardíacas morfológicas e funcionais são limitados nesse grupo. Objetivo: Neste estudo, objetivamos avaliar as características estruturais e funcionais cardíacas e as propriedades de condução atrial em pacientes com IA não funcionante. Métodos: Trinta pacientes com IA não funcionante e 46 controles adequadamente pareados foram incluídos no estudo. Após análise hormonal e bioquímica, todos os participantes foram submetidos a ecocardiograma transtorácico para obtenção de parâmetros sistólicos e diastólicos de ambos os ventrículos, além dos tempos de condução atrial pelo ecocardiograma com Doppler tecidual. Os dados foram analisados com o Statistical Package for the Social Sciences (SPSS, Chicago, IL, Estados Unidos), versão 17.0 para Windows. P < 0,05 foi considerado estatisticamente significativo. Resultados: O índice de massa do ventrículo esquerdo (VE) e o índice de desempenho miocárdico do VE foram significativamente aumentados no grupo IA. Entre os tempos de condução atrial, os atrasos eletromecânicos intra- e interatriais foram significativamente prolongados em pacientes com IA não funcionante. Outros achados laboratoriais e ecocardiográficos foram semelhantes entre os grupos. Conclusão: Nosso estudo revelou que os tempos de condução intra- e interatrial estavam prolongados e o índice de massa do VE estava aumentado em pacientes com IA não funcionante. Esses achados podem ser marcadores de envolvimento cardíaco subclínico e de tendência a complicações cardiovasculares. Um acompanhamento rigoroso é necessário para indivíduos com IA não funcionante, devido ao aumento do risco cardiovascular.

Long Term Outcomes of Left Atrial Reservoir Function in Children with a History of Kawasaki Disease

BACKGROUND: Decreased left atrial (LA) reservoir function is reported to be associated with elevated left ventricular (LV) end diastolic pressure and LV diastolic dysfunction. Echocardiographic parameters that reflect LA reservoir function include LA total emptying fraction [(maximum LA volume - minimum LA volume) / maximum LA volume], peak LA longitudinal strain (PLALS) at systole, and LA stiffness index (E/E´/PLALS). We aimed to investigate the long-term outcomes of LV diastolic function in children with a history of Kawasaki disease (KD) (KDHx group) by assessing LA reservoir function. METHODS: Retrospectively, echocardiograms performed at a mean follow-up period of 5 years after the acute phase of KD in 24 children in the KDHx group were compared to those from 20 normal control subjects. LA total emptying fraction, PLALS, LA stiffness index, LV peak longitudinal systolic strain (ε), and strain rate (SR) were evaluated with conventional echocardiographic parameters. RESULTS: The mean age at long term follow-up echocardiography in children in the KDHx group was 6.8 years. Five children (20.8%) had coronary artery lesions (CALs) in the acute stage of KD. No children showed CALs at a mean follow-up period of 5 years after the acute phase of KD. There were no significant differences in the conventional echocardiographic parameters and in LA total emptying fraction, PLALS, LA stiffness index, LV peak longitudinal systolic ε, and SR, between the children in the KDHx and control group. CONCLUSION: LV diastolic function assessed by LA reservoir function parameters at long-term follow-up in children in the KDHx group appears to be favorable.

Assessment of left atrial function in dogs with myxomatous mitral valve disease by biplane simpson's method / Avaliação da função atrial esquerda em cães com degeneração mixomatosa de valva mitral pelo método Simpson biplanar

The relationship between the diameter of the left atrium (LA) and aorta (Ao) is considered as a prognostic factor in chronic mitral valve disease. As the left atrium is a three-dimensional structure, methods based on measurement of the chamber volume can be more accurate than linear methods.The aim of this study was to assess the feasibility of measuring LA volume with 2D echocardiography using the biplane modified Simpson (SIMP) method in 33 dogs with various classes of myxomatous mitral valve disease (MMVD), as well as to present values of LA function using the atrial diastolic and systolic volume indices (ADVI and ASVI), cardiac index (ACI) and atrial ejection fraction (AEF). We observed agreement among the LA/Ao ratio and the atrial volume indices (ADVI and ASVI) and the ACI, suggesting that the values of the variables increase as the LA/Ao ratio increases due to atrial remodeling that accompanies MMVD progression. The data demonstrated a good assessment of atrial function, allowing a better understanding of LA's role in the pathophysiology of MMVD.(AU)

A relação entre o diâmetro átrio esquerdo (AE) e da aorta (Ao) é considerada como fator prognóstico na doença crônica de valva mitral. Como o átrio esquerdo é uma estrutura tridimensional, os métodos baseados na mensuração de volume da câmara podem ser mais precisos que os métodos lineares. O objetivo deste estudo foi avaliar a viabilidade da mensuração do volume do AE com a ecocardiografia bidimensional, sendo usado o método Simpson biplanar em 33 cães com diversas classes da degeneração mixomatosa de valva mitral (DMVM), bem como apresentar valores de função do AE utilizando-se os índices de volumes atriais diastólico e sistólico (iVdA e iVsA), o índice cardíaco atrial (iCA) e a fração de ejeção atrial (FEA). Observou-se uma concordância entre a relação AE/Ao e os índices de volume atrial (iVdA e iVsA) e o iCA, o que sugere que os valores das variáveis aumentam à medida que a relação AE/Ao aumenta, devido à remodelação atrial que acompanha a progressão da DMVM. Os dados demonstram uma boa avaliação da função atrial e permitem uma melhor compreensão do papel do AE na fisiopatologia da DMVM.(AU)

Efecto inotrópico y cronotrópico del propranolol sobre aurículas extraídas de ratas con insulina-resistencia inducida por fructosa / Inotropic and chronotropic effects of propranolol in isolated atrium of rats with fructose-induced insulin-resistance

La insulina-resistencia (IR) es una deficiencia metabólica asociada princi palmente con diabetes tipo 2 y comúnmente relacionada a la etiopatogenia de enfermedades cardiovasculares, siendo el factor determinante del síndrome metabólico. La investigación pretende conocer los efectos cronotrópico e inotrópico del propranolol sobre aurículas de ratas IR. Para ello, 16 ejemplares Sprague-Dawley, fueron divididos en Grupo control, alimentado ad libitum con alimento para perros Perrarina® y Grupo experimental, alimentado con Perrarina®-manteca vegetal, y suministro de agua con fructosa (20%)-sacarosa (20%) durante ocho meses. Al finalizar este periodo, se verificó la insulina-resistencia y las aurículas extraídas se mantuvieron en solución Krebs (37ºC, pH 7,4; 95% O2 - 5% CO2), en baño de órganos aislados marca Letica®, conectado a un polígrafo Grass®, registrándose la frecuencia de los latidos y evaluando las diferencias a través de la prueba t de Student (grado de significancia p<0,05). Se establecieron curvas dosis-respuesta acumulativas con isoproterenol y previa incubación de 15 minutos con propranolol (1x10 -6 M), registrándose un efecto cronotrópico negativo en el grupo control mas no así en las ratas IR, estableciéndose diferencias significativas entre el porcentaje de incremento de los latidos/seg en ambos grupos (Control 58,81±4,08; IR 68,84±4,16; p<0,001). La máxima fuerza de contracción auricular alcanzada por el grupo IR con propranolol (278,47±11,22), generó diferencias significativas (p<0,001), en comparación con el grupo control (42,60±3,13), evidenciándose que el propranolol no generó bloqueo sobre los receptores beta-adrenérgicos auriculares de las ratas insulina-resistentes.

Insulin resistance (IR) is a metabolic deficiency associated with type 2 diabe tes and commonly related to the pathogenesis of cardiovascular diseases, being the determining factor of the metabolic syndrome. This research aims to understand the chronotropic and inotropic effects of Propranolol in isolated atrium of rats with fructose-induced insulin-resistance. For this reason, 16 male Sprague-Dawley rats were assigned to two groups and given ad libitum access to one of the following diets: Perrarina® dog chow or Perrarina® dog chow supplemen ted with vegetable shortening and with fructose (20%) and sucrose (20%) added to the water supply. Both groups were maintained on their respective dietary regimens for eight months. At the end of this period insulin resistance was verified by routine blood test. The rat hearts were rapidly removed, and the atria were dissected and kept in Krebs solutions (37ºC, pH 7.4; 95% O2 - 5% CO2) in an isolated organ bath Letica®, connected to a polygraph Grass®, registering atria frequency. The Student ́s t-test was used to evaluate statistical differences between the two groups (p<0.05). Cumulative dose-response curves with isoproterenol were established in basal condition, and after fifteen minutes of pre-incubation with propranolol (1x10 -6 M). A significant positive chronotropic effect was observed in IR rats (8.84±4.16 vs 58.81±4.08 beats/sec of control; p<0.001). The maximum force of atrial contraction after pre-incubation with propranolol was significantly higher in the IR group (278.47±11.22 atrial contraction percentage; p<0.001). These findings suggest that a blunted response of atrial β-adrenoceptor to propranolol exists in rats with fructose-induced insulin-resistance.

Left Atrial Deformation Analysis in Patients with Corrected Tetralogy of Fallot by 3D Speckle-Tracking Echocardiography (from the MAGYAR-Path Study) / Análise por Speckle-Tracking com Ecocardiografia 3D da Deformação de Átrio Esquerdo em Pacientes com Tetralogia de Fallot Corrigida (do MAGYAR-Path Study)

Abstract Background: Three-dimensional (3D) echocardiography coupled with speckle-tracking echocardiographic (STE) capability is a novel methodology which has been demontrated to be useful for the assessment of left atrial (LA) volumes and functional properties. There is increased scientific interest on myocardial deformation analysis in adult patients with corrected tetralogy of Fallot (cTOF). Objectives: To compare LA volumes, volume-based functional properties and strain parameters between cTOF patients and age- and gender-matched healthy controls. Methods: The study population consisted of 19 consecutive adult patients with cTOF in sinus rhythm nursing at the University of Szeged, Hungary (mean age: 37.9 ± 11.3 years, 8 men, who had repair at the age of 4.1 ± 2.5 years). They all had undergone standard transthoracic two-dimensional Doppler echocardiographic study extended with 3DSTE. Their results were compared to 23 age- and gender-matched healthy controls (mean age: 39.2 ± 10.6 years, 14 men). Results: Increased LA volumes and reduced LA emptying fractions respecting cardiac cycle could be demonstrated in cTOF patients compared to controls. LA stroke volumes featuring all LA functions showed no differences between the 2 groups examined. LA global and mean segmental uni- and multidirectional peak strains featuring LA reservoir function were found to be diminished in adult patients with cTOF as compared to controls. Similarly to peak strains reduced global and mean segmental LA strains at atrial contraction characterizing atrial booster pump function could be demonstrated in cTOF patients as compared to controls. Conclusions: Significant deterioration of all LA functions could be demonstrated in adult patients with cTOF late after repair.

Resumo Fundamento: Ecocardiografia tridimensional (3D) acoplada à técnica de speckle-tracking (3DSTE) é uma nova metodologia útil para a avaliação de volumes e propriedades funcionais do átrio esquerdo (AE). Há crescente interesse científico na análise da deformação miocárdica em adultos com tetralogia de Fallot corrigida (cTOF). Objetivos: Comparar os volumes de AE, propriedades funcionais baseadas no volume e parâmetros de strain entre pacientes com cTOF e controles saudáveis pareados por idade e sexo. Métodos: A população do estudo consistiu em 19 adultos com cTOF consecutivos, em ritmo sinusal, acompanhados na Universidade Szeged, Hungria (idade média: 37,9 ± 11,3 anos; 8 homens; com correção cirúrgica aos 4,1 ± 2,5 anos de idade). Todos foram submetidos a ecocardiografia transtorácica bidimensional com Doppler padrão e 3DSTE. Os resultados foram comparados aos de 23 controles saudáveis pareados por idade e sexo (idade média: 39,2 ± 10,6 anos; 14 homens). Resultados: Aumento dos volumes de AE e redução das frações de esvaziamento de AE em relação ao ciclo cardíaco foram demonstrados em pacientes com cTOF em comparação aos dos controles. Os volumes de ejeção de AE caracterizando todas as funções do AE não diferiram entre os dois grupos. Strains de AE global e segmentar médio uni- e multidimensional, caracterizando função de reservatório de AE, estavam diminuídos em adultos com cTOF em comparação aos de controles. À semelhança dos strains de pico, reduzidos strains de AE global e segmentar médio na contração atrial, caracterizando função de bomba atrial, foram demonstrados em pacientes com cTOF em comparação aos de controles. Conclusões: Demonstrou-se significativa deterioração das funções de AE em adultos com cTOF em fase tardia após correção.

Atrial Strain and Strain Rate: A Novel Method for the Evaluation of Atrial Stunning / Strain Atrial e Strain Rate: Novo Método para Avaliar Atordoamento Atrial

Abstract Background: Atrial fibrillation (AF) is the most common arrhythmia seen in adults. Atrial stunning is defined as the temporary mechanical dysfunction of the atrial appendage developing after AF has returned to sinus rhythm (SR). Objectives: We aimed to evaluate atrial contractile functions by strain and strain rate in patients with AF, following pharmacological and electrical cardioversion and to compare it with conventional methods. Methods: This study included 41 patients with persistent AF and 35 age-matched control cases with SR. All the AF patients included in the study had transthoracic and transesophageal echocardiography performed before and after. Septum (SEPsSR), left atrium (LAsSR) and right atrium peak systolic strain rate (RAsSR) were defined as the maximum negative value during atrial contraction and septum (SEPε), left atrium (LAε) and right atrium peak systolic strain (RAε) was defined as the percentage of change. Parameters of two groups were compared. Results: In the AF group, 1st hour and 24th hour LAε, RAε, SEPε, LAsSR, RAsSR, SEPsSR found to be significantly lower than in the control group (LAε: 2.61%±0.13, 3.06%±0.19 vs 6.45%±0.27, p<0.0001; RAε: 4.03%±0.38, 4.50%±0.47 vs 10.12%±0.64, p<0.0001; SEPε: 3.0%±0.22, 3.19%±0.15 vs 6.23%±0.49, p<0.0001; LAsSR: 0.61±0.04s-1, 0.75±0.04s- 1 vs 1.35±0.04s-1, p<0.0001; RAsSR: 1.13±0.06s-1, 1.23±0.07s-1 vs 2.10±0.08s- 1, p<0.0001; SEPsSR: 0.76±0.04s- 1, 0.78±0.04s- 1 vs 1.42±0.06 s- 1, p<0.0001). Conclusion: Atrial strain and strain rate parameters are superior to conventional echocardiographic parameters for the evaluation of atrial stunning in AF cases where SR has been achieved.

Resumo Fundamento: A fibrilação atrial (FA) é a arritmia mais comum em adultos. Define-se atordoamento atrial como a disfunção mecânica temporária do apêndice atrial que se desenvolve depois de reversão da FA ao ritmo sinusal (RS). Objetivos: Avaliar as funções atriais contráteis através de strain atrial e strain rate em pacientes com FA, após cardioversão farmacológica e elétrica, assim como compará-los com os métodos convencionais. Métodos: Este estudo incluiu 41 pacientes com FA persistente e 35 controles com RS e pareados por idade. Todos os pacientes com FA incluídos neste estudo foram submetidos a ecocardiografia transtorácica e transesofágica antes e após. Strain rates de pico sistólico do septo (SEPsSR), do átrio esquerdo (LAsSR) e do átrio direito (RAsSR) foram definidas como o máximo valor negativo durante contração atrial. Strains de pico sistólico do septo (SEPε), do átrio esquerdo (LAε) e do átrio direito (RAε) foram definidas como porcentagem de mudança. Resultados: No grupo com FA, os parâmetros LAε, RAε, SEPε, LAsSR, RAsSR e SEPsSR da 1a hora e da 24a hora foram significativamente mais baixos que no grupo controle (LAε: 2,61%±0,13; 3,06%±0,19 vs 6,45%±0,27; p<0,0001; RAε: 4,03%±0,38; 4,50%±0,47 vs 10,12%±0,64; p<0,0001; SEPε: 3,0%±0,22; 3,19%±0,15 vs 6,23%±0,49; p<0,0001; LAsSR: 0,61±0,04s-1; 0,75±0,04s-1 vs 1,35±0,04s-1; p<0,0001; RAsSR: 1,13±0,06s-1; 1,23±0,07s-1 vs 2,10±0,08s-1; p<0,0001; SEPsSR: 0,76±0,04s-1; 0,78±0,04s-1 vs 1,42±0,06 s-1; p<0,0001). Conclusão: Os parâmetros strain atrial e strain rate são superiores aos parâmetros ecocardiográficos convencionais para avaliar atordoamento atrial em pacientes com FA que reverteram ao RS.

Biological significance of miR-126 expression in atrial fibrillation and heart failure

We investigated the biological significance of microRNA-126 (miR-126) expression in patients with atrial fibrillation (AF) and/or heart failure (HF) to examine the possible mechanism of miR-126-dependent AF and development of HF. A total of 103 patients were divided into three groups: AF group (18 men and 17 women, mean age: 65.62±12.72 years), HF group (17 men and 15 women, mean age: 63.95±19.71 years), and HF-AF group (20 men and 16 women, mean age: 66.56±14.37 years). Quantitative real-time PCR was used to measure relative miR-126 expression as calculated by the 2−ΔΔCt method. miR-126 was frequently downregulated in the 3 patient groups compared with controls. This reduction was significantly lower in permanent and persistent AF patients than in those with paroxysmal AF (P<0.05, t-test). Moreover, miR-126 expression was markedly lower in the HF-AF group compared with the AF and HF groups. The 3 patient groups had higher N-terminal prohormone brain natriuretic peptide (NT-proBNP) levels, lower left ventricular ejection fraction (LVEF), larger left atrial diameter, and higher cardiothoracic ratio compared with controls. There were significant differences in NT-proBNP levels and LVEF among the AF, HF, and HF-AF groups. Pearson correlation analysis showed that relative miR-126 expression was positively associated with LVEF, logarithm of NT-proBNP, left atrial diameter, cardiothoracic ratio, and age in HF-AF patients. Multiple linear regression analysis showed that miR-126 expression was positively correlated with LVEF, but negatively correlated with the logarithm of NT-pro BNP and the cardiothoracic ratio (all P<0.05). Serum miR-126 levels could serve as a potential candidate biomarker for evaluating the severity of AF and HF. However, to confirm these results, future studies with a larger and diverse patient population are necessary.

Características, benefícios e consequências dos algoritmos deminimização da estimulação do ventrículo direito por dispositivos de estimulação cardíaca artificial / Characteristics, benefits and consequences of right ventricle stimulation minimizing algorithms by artificial cardiac pacing devices

Os dispositivos implantáveis de estimulação cardíaca artificial (marcapasso definitivo, cardiodesfibriladore terapia de estimulação multissítio para ressincronização cardíaca) têm benefícios bem estabelecidos e indicações sem expansão. Diversos estudos e publicações têm demonstrado que a estimulação cardíaca artificial convencional não é isenta de efeitos adversos (dissincronia ventricular, risco de insuficiência cardíaca e mortalidade). O progresso tecnológico da eletroterapia cardíaca trouxe novos algoritmos e estratégias de programação dos dispositivos, particularmente os que minimizam a estimulação do ventrículo direito por programação do intervalo atrioventricular. Atualmente, tanto para portadores de marcapasso definitivo como, particularmente, para portadores de cardiodesfibrilador implantável, são recomendadas estratégias que explorem ao máximo a condução atrioventricular intrínseca, quando esta é confiável, com o objetivo de produzir complexos com QRS estreito, evitando as potenciais consequências deletérias da ativação artificial do ventrículo direito. Esta revisão aborda as diferenças entre sequência atrioventricular e sincronia atrioventricular produzidas por esses algoritmos, e o surgimento de um outro virtual conflito de paradigmas: permitir intervalos atrioventriculares não fisiológicos, gerando potencialmente dissincronia atrioventricular mas com QRS estreito, ou estimular artificialmente o ventrículo direito com intervalo atrioventricular fisiológico e QRS largo?.

Implantable artificial cardiac pacing devices (permanent pacemakers, cardioverter-defibrillators and multisite pacing for cardiac resynchronization therapy) have well-established benefits and expanding indications. Several studies and publications have demonstrated that conventional artificial cardiac pacing is not free from adverse effects (ventricular desynchronization, risk of heart failure and mortality). Technological advances in cardiac electrotherapy have led to new algorithms and device programming strategies, particularly those that minimize right ventricle pacing by atrioventricular interval programming. Currently and when ever reliable, strategies that explore intrinsic atrioventricular conduction to a maximum are recommended for carriers of permanent pacemakers and implantable cardioverter-defibrillators to avoid the potential deleterious consequences of artificial right ventricle activation. This review addresses the differences between atrioventricular synchrony and atrioventricular sequencing produced by these algorithms and the emergence of another virtual paradigm conflict: should weallow long, non-physiological, atrioventricular intervals, potentially generating atrioventricular desynchronization with a narrow QRS or artificially stimulate the right ventricle with a physiological atrioventricular interval and awide QRS?.

Relação do índice de massa corpórea com as mudanças na geometria e função cardíaca em 5.898 pacientes valiados por Ecocardiografia Transtorácica / Relationship of Body Mass Index with Changes in Cardiac Geometry and Function in 5.898 Patients Evaluated

Introdução: Este estudo descreve a relação entre índice de massa corpórea (IMC) e a geometria e função cardíacaanalisada por ecocardiografia transtorácica. Materiais e métodos: Analisaram-se 5.898 estudos ecocardiográficos, numa faixa de idade entre 18,0 e 98,6 anos. Resultados: O IMC variou de 15,23 a 49,61 Kg/m2. O aumento do IMC teve uma associação direta estatisticamente significativa com a massa ventricular esquerda, observando-se inicialmente hipertrofia concêntrica leve, que se faz excêntrica na medida em que aumenta, especialmente quando se normaliza pela relação alométrica (altura2,7). Também observou-se aumento do volume de ejeção e do débito cardíaco e evidenciou-se associação inversa entre o índice de massa corpórea e a relação E/A de enchimento mitral, com diminuição sigificativa da velocidade de e’ doDoppler tecidual, demonstrando-se disfunção diastólica do tipo alteração do relaxamento do ventrículo esquerdono indivíduo com sobrepeso ou obeso. Observou-se aumento discreto, porém significativo, da área e do volumeindexado do átrio esquerdo para a massa corpórea. Não houve diferenças na geometria e função do ventrículo direito. Conclusões: O presente estudo evidenciou uma associação direta significativa entre o índice de massa corpórea (IMC) e a massa miocárdica ventricular esquerda. A indexação da massa do VE à altura2,7 evita artefatos relacionados à normalização pela área de superfície corpórea, principalmente em indivíduos com obesidade grau II e III.

Introduction: This study describes the relationship between Body Mass Index (BMI) and the cardiac geometry and heart function assessed bytransthoracic echocardiography.Materials and methods: We analyzed 5,898 echocardiographic studies in an age range between 18.0 and 98.6 years.Results: The BMI ranged from 15.23 to 49.61 kg/m2 . The increased BMI had a statistically significant direct association with left ventricular mass initially observing a light concentric hypertrophy, which becomes eccentric as it increases, especially when allometric ratio is normalized (Height2.7). An increase in ejection volume and cardiac output was observed, as well as an inverse association between body mass index and the E/A ratio of mitral filling, with a significant reduction of e’ velocity of tissue Doppler, showing a relaxation-type diastolic dysfunction in overweight or obese individuals. We observed a slight yet significant increase in the left atrial area and volume indexed to body mass. There were no differences in the right ventricular geometry and function.Conclusions: The present study demonstrated a significant direct association between the increase in BMI and LV myocardial mass. IndexingLV mass to height 2.7 avoids artifacts related to body mass index, especially in subjects with grade II and III obesity.

Avaliação ecocardiográfica de centenários / Echocardiographic Assessment of Centenary Patients

Fundamento: O ecocardiograma é uma ferramenta diagnóstica capaz de detectar diversos parâmetros com potencial de auxiliar o cardiologista na conduta do paciente. O conhecimento desses parâmetros em centenários pode levar ao maior entendimento do processo saúde/doença nessa população.Objetivos: Avaliar os parâmetros ecocardiográficos em centenários, uma vez que não foi encontrado na literaturatrabalho que contemplasse tais dados nesse grupo. Métodos: Foram avaliados por meio de ecocardiograma transtorácico 16 pacientes centenários, com baixo estado de dependência e fragilidade e sem histórico de cardiopatia.Resultados: Diâmetros, áreas, volumes e volumes indexados do átrio esquerdo encontraram-se aumentados em 31,25%, 50%, 68,75% e 87,5% dos pacientes, respectivamente. Os diâmetros diastólicos absolutos e indexados do ventrículo esquerdo acharam-se aumentados em 6,25% e 68,75%, respectivamente. A massa ventricular esquerda absoluta eindexada estava aumentada em 37,5% e 75% dos idosos. Apresentaram padrão de hipertrofia excêntrica 62,5% dos indivíduos. Déficit de contratilidade segmentar ocorreu em 31,25% da amostra. Pressão sistólica em artéria pulmonar acima de 40 mmHg ocorreu em 61,5% dos pacientes. Conclusão: As dimensões aumentadas das câmaras esquerdas e massa ventricular esquerda principalmente quando quantificadas pela superfície corporal apontam para a necessidade de indexação dos valores nesses indivíduos. A presençade déficit segmentar em 31,25% dos pacientes sugere que isquemia silenciosa seja relativamente comum em centenários. Hipertensão pulmonar em 61,5% dos pacientes sem elevação da pressão capilar pulmonar faz suspeitar de doença pulmonar não diagnosticada.

Background: Echocardiography is a diagnostic tool capable of detecting different parameters with the potential to assist the cardiologists inpatients management. Being aware of these parameters in centenary patients may lead to greater understanding of the health/disease process in this population. Objectives: To evaluate echocardiographic parameters in centenary patients, since no study covering such data in that group was found in the literature. Methods: Sixteen centenary patients with low state of dependence and weakness and no history of heart disease were assessed by transthoracic echocardiography.Results: Diameters, areas, volumes and indexed left atrial volumes were found to be increased by 31.25%, 50%, 68.75% and 87.5% of patients, respectively. Absolute and indexed left ventricular diastolic diameters were found to be increased by 6.25% and 68.75%, respectively. Absolute and indexed left ventricular mass was increased by 37.5% and 75% of elderly patients. The study found that 62.5% of individuals presented a pattern of eccentric hypertrophy. Deficit of segmental contractility occurred in 31.25% of the sample. Pulmonary arterial systolic pressure above 40 mm Hg occurred in 61.5% of patients. Conclusion: Increased dimensions of left chambers and left ventricular mass especially when quantified by body surface point out to the need for indexing the values in these individuals. The presence of segmental deficit in 31.25% of patients suggests that silent ischemia is relativelycommon in centenarians. Pulmonary hypertension in 61.5% of patients without elevated pulmonary capillary pressure leads to suspectedundiagnosed lung disease.

Metabolic syndrome is associated with atrial electrical and mechanical dysfunction

In this study, we aimed to investigate the left atrial [LA] electrical and mechanical functions in patients with metabolic syndrome [MetS]. Subjects and The study population consisted of 87 patients with MetS and 67 controls. Intra-atrial and interatrial electromechanical delays [EDs] were measured with tissue Doppler imaging. P-wave dispersion [Pd] was calculated from the 12-lead electrocardiograms. LA volumes were measured echocardiographically by the biplane area-length method. Intra-atrial and interatrial EDs and Pd were significantly higher in patients with MetS [10.3 +/- 6.3, 21.0 +/- 11.5 and 41.7 +/- 10.8] than in controls [7.4 +/- 5.5, 12.3 +/- 10.4 and 29.2 +/- 7.4; p = 0.003, p < 0.001 and p < 0.001, respectively]. The LA preatrial contraction volume and active emptying volumes were higher in this population, but the LA passive emptying fraction was lower. In the multivariate linear regression analysis, the presence of MetS, LA active emptying volume and left ventricular early diastolic [E] wave velocity/late diastolic [A] wave velocity [E/A] ratios were independent correlates of interatrial ED [p = 0.002, p = 0.001 and p = 0.025, respectively]. This study showed that intra-atrial and interatrial EDs and Pd were prolonged and LA mechanical functions were impaired in patients with MetS

Análise da função diastólica e função atrial em ciclistas de alto desempenho por meio da ecocardiografia tridimensional / Analysis of diastolic function and atrial function in high performance cyclists through three-dimensional echocardiography

Objetivos: Avaliar a função diastólica e a função atrial esquerda por meio do estudo com Doppler e ecocardiograma tridimensional em ciclistas de alto desempenho; comparar as variáveis estudadas a controles não esportistas. Métodos: Foram estudados 18 ciclistas profissionais (homens, idade 29, 5±4, 3 anos) e 18 indivíduos controles não esportistas (homens, idade 28, 8±5, 8 anos). Todos os indivíduos foram submetidos a ecocardiograma bidimensional e tridimensional com medidas de variáveis de função diastólica e de esvaziamento atrial como volume atrial esquerdo máximo, mínimo e antes de sua contração. Com base nestes volumes fundamentais foram calculadas a função de esvaziamento ativo, passivo e total, bem como a força de contração atrial. Resultados: Os indivíduos de ambos grupos apresentaram variáveis antropométricas semelhantes. Foi observado no grupo ciclista em relação aos controles: menor velocidade da onda A’ (5,9cm/s ± 2,2 versus 7,6 ± 2,3cm/s, com P=0,03), menor força de contração atrial (4,7 ±1,4Kdyn Vs. 6,2 ± 2,1Kdyn, com P= 0,02) e maior fração de esvaziamento passivo (43,8 ± 12,8% versus 34,8 ± 10,4% com P=0,03). Foi observada correlação linear entre a velocidade da onda A’ e a força de contração atrial no grupo dos ciclistas (r=0,80, P<0,05), entre a força de contração atrial e a fração de esvaziamento passivo (r=-0,88, P<0,05) e entre a força de contração atrial e o volume atrial antes de sua contração (r=0,65, P<0,05). Conclusão: O grupo ciclistas apresentou aumento do componente passivo em detrimento de uma redução do componente ativo no esvaziamento atrial total, o que mostrou estar correlacionado à atividade diastólica supernormal nesse grupo.

Objectives: To assess left ventricular diastolic and atrial function by means of Doppler and three-dimensional echocardiography of high-performance cyclists; To compare the variables studied for non-athlete controls. Methods: The study included 18 professional cyclists (men, age 29, 5±4, 3 years) and 18 non-athlete control individuals (men, age 28, 8±5, 8 years). All individuals underwent two-dimensional and three-dimensional echocardiography including measures of diastolic function variables and atrial emptying, such as maximum, minimum and before contraction left atrial volume. Based on these fundamental volumes, active, passive and total emptying function, and atrial contraction strength were calculated. Results: The individuals of both groups had similar anthropometric variables. The following was observed in the cyclist group as for the controls: lower A’ wave velocity (5.9 cm/s ± 2.2 versus 7.6 ± 2.3 cm/s, with P = 0.03), smaller atrial contraction force (4.7 ± 1,4Kdyn vs. 6.2 ± 2.1Kdyn, P = 0.02) and greater passive emptying fraction (43.8% ± 12.8 versus 34.8 ± 10.4% with P = 0.03). A linear correlation was found between A’ wave velocity and atrial contraction force in the cyclists group (r = 0.65, P <0.05), between atrial contraction force and passive emptying fraction (r = 0.80, P <0.05) and between atrial contraction and volume before contraction (r = 0.65, P < 0.05). Conclusion: The cyclists group showed an increase in the passive component to the detriment of a reduction in the active component in total atrial emptying, which was showed to be correlated with supernormal diastolic activity in this group.

Derivação ventriculoatrial percutânea – Nota técnica / Derivation percutaneous atrial ventricle - Technical Note

Descrição passo a passo de técnica de derivação ventriculoatrial utilizando punção cervical percutâneapor técnica de Seldinger. O objetivo é demonstrar e difundir entre os neurocirurgiões brasileiros umaforma alternativa segura, rápida e e'caz de introdução e instalação de cateter venoso até o átrio direito,sem necessidade de dissecção venosa convencional. São vantagens a redução do tempo cirúrgico eo melhor resultado cosmético, sem aumento signi'cativo do custo...

Step-by-step technique using ventriculoatrial shunt through percutaneous cervical puncture by Seldinger’s technique. The goal is to demonstrate and spread among Brazilian neurosurgeons an alternative safe, fast and effective way to introduce and install venous catheter up to the right atrium without the need for conventional venous dissection. Advantages of the method are shorter surgical time and better cosmetic results, without significant increase in the cost...

Infliximab; an Anti-TNF-Alpha Agent; Improves Left Atrial Abnormalities in Patients with Rheumatoid Arthritis: Preliminary Results : Cardiovascular Topic

Background : Rheumatoid arthritis (RA) is associated with increased cardiovascular morbidity and mortality. In the current prospective study; we addressed the impact of RA on left atrial (LA) function and electrical remodelling. Further; we tried to demonstrate the effects of infliximab; an anti-TNF-alpha agent; on echocardiographical LA abnormality in RA patients with preserved left ventricular (LV) ejection fraction. Methods: We compared 38 female RA patients without clinical evidence of heart disease and 30 female controls without RA and clinical evidence of heart disease. Further; we compared RA patients receiving infliximab and increasing doses of prednisolone over a three-month period. At baseline and post treatment; this study assessed (1) LA and LV parameters using conventional and speckle tracking echocardiography (STE); and (2) electrocardiographic P-wave changes. Results: The values of C-reactive protein (CRP); isovolumic relaxation time (IVRT); A wave; and deceleration time (DT) were significantly higher in RA patients compared to the control group (p 0.05); whereas E/E' and E/A values were found to be lower (p 0.05) in RA patients. E/E' values were lower in prednisolone- compared to infliximab-treated patients (p 0.05). After three months of infliximab and prednisolone treatment; CRP and disease activity score (DAS 28) values decreased in both groups (p 0.05); and Duke activity status index (DASI) increased (p 0.05). Maximal left atrial volume index (LAVImax); pre-contraction left atrial volume index (LAVIpreA) and maximum P wave (Pmax) of the RA patients were higher compared to the control group (p 0.05); whereas LA global strain was found to be lower (p 0.05). There was no difference in Pmax values between groups before and after the treatment period. E/E'; LAVImax and LAVIpreA values of infliximab-treated patients decreased and LA global strain increased after three months of therapy compared to baseline (p 0.05). At baseline in both treatment groups; E/E' and LA global late diastolic strain rate were lower in prednisolone- compared to infliximab-treated patients (p 0.05). Conclusion: There was echocardiographic LA abnormality in these RA patients. In this patient group there was also a meaningful increase in maximum P wave assessed by

Ionic mechanism underlying distinctive excitability in atrium and ventricle of the heart / 生理学报

Cellular excitability is an important physiological factor in maintaining normal cardiac activity. The present study was designed to investigate the ionic mechanism underlying different excitability in atrial and ventricular myocytes of guinea pig heart using a whole-cell patch configuration. We found that excitability is lower in ventricular myocytes than that in atrial myocytes. Although the density of voltage-gated fast Na(+) current (INa) was lower in ventricular myocytes, it would not correlate to the lower excitability since its availability was greater than that in atrial myocytes around threshold potential. Classical inward rectifier K(+) current (IK1) was greater in ventricular myocytes than that in atrial myocytes, which might contribute in part to the lower excitability. In addition, the transient outward K(+) current with inward rectification (Itoir) elicited by depolarization was greater in ventricular myocytes than that in atrial myocytes and might contribute to the lower excitability. In ventricular myocytes, Ba(2+) at 5 µmol/L significantly inhibited Itoir, enhanced excitability, and shifted the threshold potential of INa activation to more negative, and the effect was independent of affecting INa. Our results demonstrate the novel information that in addition to classical IK1, Itoir plays a major role in determining the distinctive excitability in guinea pig atrial and ventricular myocytes and maintaining cardiac excitability. More effort is required to investigate whether increase of Itoir would be protective via reducing excitability.

Baixa concordância entre diâmetro e volume do átrio esquerdo em pacientres com maior risco de fibrilação atrial / Low agreement between left atrial diameter and volume in patients with increased risk of atrial fibrillation

Introdução: O aumento do átrio esquerdo (AE) está diretamente relacionado a disfunção diastólica do VE(VD) e ambos estão associados a ocorrência de fibrilação atrial (FA). Embora o diâmetro (DAE) seja mundialmente usado como medida do AE, muitas evidencias mostram que o volume indexado para a superficie corporea (indVAE) é mais acurado. Objetivo: Avaliar a correlação entre DAE e IndVAE em pacientes (pt) com DD. Material e Métodos: Dentre 892 pacientes encaminhados ao ecocardiograma, (ECO) de uma clínica terciaria no DF, entre janeiro de 2008 a junho de 2009, foram selecionados 540 com addos clínicos e ecocardiograficos, dos quais foram excluidos 21, devido a idade < 18 anos e 18 pacientes com lesão valvar mitral > discreta. A função diastólica foi considerada, significativamente, anormal se E/e'>-15 (elevação das pressões de encihmento ventricular esquerdo). A concordância entre as medidas de DAE e IndVAE foi avaliada da seguinte forma concordante (IndVAE<- 40mm ou IndVAE > 40); e discordante (indVAE<- 32 e DAE > 40 ou IndVAE > 32 e DAE <- 40.). Resultados: Dos 501 pacientes estudados, 33 (6,6%) tinham E/e' >- 15 e 468 (93,4%) E/e' < 15. Houve boa correlação entre DAE e IndVAE tanto para pacientes com E/e' >- 15 (r=0,57), quando para pacientes com E/e' < 15 (r=0,62). A discordância entre DAF e IndVAE foi maior nos pacientes...

Background: Increased left atrial (LA) is directly related to LV diastolic dysfunction (DD), and both are associated with atrial fibrillation (AF). Although the diameter (LAD) is used as a measure of LA, many evidences show that LA volume index (iLAV) is more accurate. Objective: To evaluate the correlation between LAD and iLAV in patients (pt) with DD. Material and Methods: Among 892 pt referred to the echocardiography laboratory of a tertiary clinic, from Jan/08 to June/09, 540 pt with clinical and echocardiographic data were selected and 21 were excluded for being <18yo and 18 pt presenting more than mild mitral valve lesion. Diastolic function was considered abnormal when E/e¡¯ ratio ¡Ý 15 (elevated left ventricular filling pressures). Agreement between measures of LAD and iLAV was evaluated: agreement if iLAV ¡Ü 32ml/m2 and LAD ¡Ü 40mm or iLAV > 32 and LAD > 40; and disagreement if iLAV ¡Ü 32 and LAD > 40 or iLAV > 32 and LAD ¡Ü 40. Results: Of 501 pt, 33 (6.6%) presented E/e¡¯ ratio ¡Ý 15 and 468 (93.4%) < 15. There was a good correlation between LAD and iLAV in both patients with E/e¡¯ ¡Ý 15 (r = 0.57), and E/e¡¯ < 15 (r = 0.62). The disagreement between LAD and iLAV was higher in p with E/e¡¯ ¡Ý 15 (21.2% vs 9% - p <0.0001). Clinical and echocardiographic data were, respectively, for E/e¡¯ ¡Ý15 and E/e¡¯ < 15: male 54.5% vs 45.5% (p = ns), age 73.2 ¡À 12.4 vs 50.1 ¡À 16.5 (p <0.0001), LAD (cm) 38.8 ¡À 6.3 vs 35.2 ¡À 5.2 (p <0.0001); iLAV (ml/m2) 35 ¡À 16.2 x 21.9 ¡À 7 (p <0.0001), EF (%) 60.7 ¡À 16.2 vs 70.7 ¡À 6.9 (p <0.0001), E/e¡¯ 21 , 1 ¡À 8.1 vs 16.5 ¡À 2.4 (p <0.0001), HBP 81.8% vs. 50.2% (p <0.0001), DM 21.2% vs. 9.4% (p = 0.04); CHF 24.2% vs. 3.2% (p <0.0001), CAD 33.3% versus 9% (p <0.0001). Conclusion: Patients with elevated left ventricular filling pressures are older, have larger LA diameter and volume, worse EF and higher incidence of HBP, diabetes, CHF and CAD. There is less agreement between LAD and iLAV in these patients.