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Insights into left atrial response to pressure and volume overloadLisi, Matteo January 2016 (has links)
The general purpose of this thesis is to establish the ability of Speckle Tracking Echocardiography (STE) in assessing left atrial (LA) response to pressure and volume overload respectively in aortic stenosis (AS) and mitral regurgitation (MR), and to evaluate its accuracy in predicting LA and right ventricular (RV) fibrosis in patients with end-stage heart failure (HF) undergoing heart transplantation (HTx). I demonstrated that assessment of left ventricular (LV) long axis systolic velocity and amplitude of excursion is more sensitive than simple determination of ejection fraction (EF) for revealing the beneficial impact of MR surgery on overall LV systolic performance. Severe symptomatic AS is associated with LA enlargement and compromised mechanical function with a high incidence of peri-operative atrial fibrillation (AF). Valve replacement reverses these abnormalities and regains normal atrial function, a behaviour which is directly related to the severity of pre-operative LV outflow tract obstruction. Early identification of LA size and function disturbances, as shown by myocardial strain measurements might contribute to better patient’s recruitment for a safe valve replacement. In late stage HF patients, the right ventricle is enlarged, with reduced systolic function due to significant myocardial fibrosis. RV free wall myocardial deformation is the most accurate function measure that correlates with the extent of RV myocardial fibrosis and functional capacity. In patients with preserved EF, severe MR masks LV and LA myocardial dysfunction and correlates with symptoms and post-operative cavity function instability. Three months after MVR, the underlying myocardial disturbances are unmasked suggesting that most pre-operative measurements are subject to loading conditions. Finally LA volume and PALS remain the main predictors of post-operative AF, thus should be used for stratifying surgical risk. STE has been shown to accurately determine the severity of impairment of LA myocardial function shown by suppressed PALS which was the strongest predictor of the presence and extent of fibrosis, over and above other structure and function parameters. These findings may assist in better stratifying patients with end stage HF and identifying particularly those requiring HTx.
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Mechanical and histological disturbances in advanced heart failure and cardiac transplantationCameli, Matteo January 2016 (has links)
The general purpose of this thesis is to establish capability and accuracy of speckle tracking echocardiography (STE) in assessing left atrial (LA), left ventricular (LV) and right ventricular (RV) function and their correlation with myocardial fibrosis, filling pressure and clinical outcomes in advanced heart failure (HF) patients before and after heart transplantation (HT). I demonstrated that HT recipients had impaired LV twist dynamics in the form of reduced rotation twist angle and untwist rate but time to peak twist was not different from the age matched controls and other cardiac surgical patients. With a longitudinal study conducted on patients with refractory HF, the best prognostic power has been shown by RV strain analysis. Among the indexes of LV function, the LV ejection fraction (LVEF) demonstrated the lowest diagnostic accuracy; instead LV global circumferential strain (GCS) showed a better sensitivity and specificity than LV global longitudinal strain (GLS). When analyzing the relationship between different severity of myocardial fibrosis and LV cavity function, the strongest function parameter that correlated with severity of myocardial fibrosis was GLS. In contrast, none of diastolic LV function or even measures of exercise capacity correlated with myocardial fibrosis. In patients with end-stage HF, global peak atrial longitudinal strain (PALS), an index of atrial reservoir function was dependent by pulmonary capillary wedge pressure (PCWP) and LV fibrosis, but not influenced by LV systolic function. Results from this study confirm previous evidence of correlation between impaired global PALS and increased PCWP.
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Évaluation échocardiographique des effets du pimobendane dans le traitement des maladies valvulaires dégénératives canines asymptomatiquesOuellet, Mathieu 01 1900 (has links)
Contexte : Les maladies valvulaires dégénératives (MVD) représentent la pathologie cardiaque acquise la plus fréquente chez le chien. Malgré une recherche active, à l’heure actuelle aucun traitement étudié ne s’est avéré
efficace dans le traitement du stade asymptomatique de la condition. Le pimobendane est un nouvel agent inodilatateur, qui s’est montré prometteur dans le traitement des stades avancés des MVD, mais peu est
connu sur ses effets hémodynamiques et son impact sur le volume de régurgitation dans les MVD naturelles asymptomatiques.
Hypothèses : L’introduction du pimobendane réduit la fraction de régurgitation (FR) chez les chiens atteints de MVD asymptomatiques.
Sujets étudiés : Vingt-quatre chiens de compagnie, appartenant à la clientèle du Centre Hospitalier Universitaire Vétérinaire (CHUV) de l’université de Montréal et affectés par une MVD de classe ISACHC 1b.
Méthode: Étude prospective, contrôlée et conduite à l’aveugle. Les chiens ont été assignés à un groupe traitement (n=19) recevant du pimobendane (0,2-0,3 mg/Kg q12h) ou à un groupe contrôle (n=5). Les évaluations échocardiographiques ont été effectuées sur une période de 6 mois.
Résultats : L’introduction du pimobendane n’a pas été associée à une diminution de la FR chez les chiens affectés par une MVD asymptomatique de classe ISACHC 1b au cours de l’étude (p=0,85). Une augmentation significative de la fraction d’éjection (80,8 +/- 1,42 vs. 69,0 +/- 2,76, p=0,0064) ainsi qu’une baisse du diamètre ventriculaire gauche télé systolique (p=0.011) ont été observées chez le groupe pimobendane au jour 30. Toutefois, cet effet sur la fonction systolique n’a pas persisté au cours des 6 mois d’évaluation. / Background: Mitral Valve disease (MVD) is the most common acquired cardiac affectation of the dog, and is therefore associated with an undeniable clinical and economical importance for veterinarians and pet
owners. Despite active research, at this time no known treatment has been proven to delay the onset of congestive heart failure. Pimobendan is a novel inodilator that has shown promising results in the treatment of
advanced MVD, but little is known about its hemodynamic effects, especially regarding the mitral regurgitant volume in naturally occurring asymptomatic MVD.
Hypothesis: Administration of pimobendan decreases the regurgitant fraction (RF) of dogs with asymptomatic MVD.
Animals: Twenty-four client-owned dogs affected by ISACHC class Ib MVD.
Methods: Prospective, blinded, controlled clinical trial. Dogs were assigned to a pimobendan (0.2-0.3 mg/Kg q12h) treatment group (n=19) or a control group (n=5). Echocardiographic evaluations were performed over a
6 month study period.
Results: Administration of pimobendan to treatment did not decrease the RF of dogs affected by asymptomatic class 1b MVD over the study period (p=0.85). There was a significant increase in the ejection fraction of the
pimobendan treated dogs at day (80.8 +/- 1.42 vs. 69.0 +/- 2.76, p=0.0064), and a decrease in systolic left ventricular diameter (p=0.011). However, this improvement in systolic function was not sustained over the 6 month trial period.
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Doppler vortography : detection and quantification of the vortices in the left ventricleMehregan, Forough 09 1900 (has links)
Nous proposons une nouvelle méthode pour quantifier la vorticité intracardiaque (vortographie Doppler), basée sur l’imagerie Doppler conventionnelle. Afin de caractériser les vortex, nous utilisons un indice dénommé « Blood Vortex Signature (BVS) » (Signature Tourbillonnaire Sanguine) obtenu par l’application d’un filtre par noyau basé sur la covariance. La validation de l’indice BVS mesuré par vortographie Doppler a été réalisée à partir de champs Doppler issus de simulations et d’expériences in vitro. Des résultats préliminaires obtenus chez des sujets sains et des patients atteints de complications cardiaques sont également présentés dans ce mémoire. Des corrélations significatives ont été observées entre la vorticité estimée par vortographie Doppler et la méthode de référence (in silico: r2 = 0.98, in vitro: r2 = 0.86). Nos résultats suggèrent que la vortographie Doppler est une technique d’échographie cardiaque prometteuse pour quantifier les vortex intracardiaques. Cet outil d’évaluation pourrait être aisément appliqué en routine clinique pour détecter la présence d’une insuffisance ventriculaire et évaluer la fonction diastolique par échocardiographie Doppler. / We propose a new method for quantification of intra-cardiac vorticity (Doppler vortography) based on conventional Doppler images. To characterize the vortices, an index called “blood vortex signature” (BVS) was obtained using a specific covariance-based kernel filter. The reliability of BVS measured by Doppler vortography was assessed in mock Doppler fields issued from simulations and in vitro experimentations. Some preliminary results issued from healthy subjects and patients with heart disease were also presented in this research project. Strong correlations were obtained between the Doppler vortography-derived and ground-truth vorticities (in silico: r2 = 0.98, in vitro: r2 = 0.86, in vivo: p = 0.004). Our results demonstrated that Doppler vortography is a potentially promising echocardiographic tool for quantification of intra-ventricular vortex flow. This technique can be easily implemented for routine checks to recognize ventricular insufficiency and abnormal blood patterns at early stages of heart failure to decrease the morbidity of cardiac disease.
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Analyse du rôle des fonctions ventriculaires longitudinales dans les défaillances cardio-circulatoires graves / Analysis of the role of longitudinal ventricular functions in severe cardiac and circulatory failuresAissaoui, Nadia 05 December 2013 (has links)
Les analyses des fonctions ventriculaires gauche (VG) et droite (VD) et des pressions de remplissage sont des éléments importants dans le contexte des défaillances cardio-circulatoires graves car elles ont des conséquences diagnostiques et pronostiques avec un impact sur les prises de décisions thérapeutiques. Toutefois, l'évaluation de la fonction myocardique en cas de choc reste difficile pour des raisons physiopathologiques et technologiques. Les paramètres de fonction ventriculaire longitudinale (FVL) pourraient avoir un intérêt dans ce domaine car ils permettent une évaluation directe d'une composante majeure de la mécanique ventriculaire. Ces paramètres ont été évalués chez les défaillances chroniques stables et ont montré leurs intérêts diagnostiques et pronostiques. Ils restent très peu étudiés dans les contextes aigues et graves. / Despite advances in management and therapies, cardiogenic shock remains a clinical challenge with high mortality rates.The analysis of left and right ventricular functions and filling pressures are important in this context because they had diagnostic and prognostic consequences with impact in therapeutic decisions. Nevertheless, the assessment of myocardial function remains difficult for physiopathologic and technical reasons. The parameters of longitudinal ventricular function (LgVF) could have an interest in this context because they permit a direct assessment of a major component of ventricular mechanics whereas ejection fraction remains a global evaluation. These indices were assessed in chronic and stable heart failure patients and were found to have prognostic and diagnostic interests. Though, they were not evaluated in the context of acute and severe cardio-circulatory failures.
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Entrainement, préparation physique et physiologique cardio-respiratoire appliquée au rugby à XV / Training, physical training and cardiovascular physiology applied to the rugby unionFornasier Santos, Charly 20 December 2018 (has links)
Le rugby à XV est un sport collectif qui se caractérise en match par des courses et des collisions de hauteintensité très variables selon les positions. La première partie des travaux, qui s’est centrée sur l’analyse del’activité par centrale d’analyse cinématique, a mis en évidence une activité de haute intensité plus importante enCoupe d’Europe qu’en TOP14 qui varie selon les cinq postes de jeu en termes de répétitions d’efforts et dedistances parcourues à haute intensité notamment chez les avants. De plus, ces activités de haute intensitédiminuent en première et deuxième mi-temps et sont différentes selon les positions. En effet, une diminution plusprécoce est observée chez les avants et les trois-quarts ailes, qui est majorée au niveau des accélérations entre lesdeux dernières périodes d’un match pour les avants démontrant un impact de la fatigue. A l’inverse, les arrièresarrivent globalement à maintenir une intensité élevée. Ainsi, au regard des résultats de la première partie, ladeuxième partie des travaux a consisté en la mise en place d’un entraînement par répétition de sprints en hypoxieinduite par hypoventilation à bas volume pulmonaire. Celui-ci a permis une amélioration significative de lacapacité à répéter des sprints après sept séances d’entraînement par hypoventilation chez les joueurs très entraînés,alors qu’aucun changement n’a été observé dans le groupe normoxie. L’entraînement en rugby à XV se caractérisepar la répétition d’efforts de haute intensité à dominante dynamique (courses) et statique (musculation, phases decombat) qui vont impacter le remodelage du ventricule gauche de manière spécifique. La troisième partie a montré,à partir d’échocardiographies de repos en mode 2D-strain, une hypertrophie physiologique majorée chez les avantscomparativement aux arrières. Cette hypertrophie s’accompagne d’une augmentation des pressions de remplissageet une diminution de la relaxation lors de la diastole, notamment chez les avants. Enfin, malgré une torsionventriculaire inchangée, les rotations et les vitesses de rotation sont plus grandes au niveau basal et plus faibles auniveau apical chez les joueurs de rugby à XV. Ainsi, cette thèse CIFRE apporte de nouvelles données au niveaude l’analyse de l’activité, des méthodes d’entraînement facilement applicables pour l’entraîneur, ainsi que desdonnées plus spécifiques à l’évaluation cardiaque de repos pour le clinicien. / Rugby union is a team sport characterized by high-intensity collisions and running efforts during gameswhich are position-dependent. Accounting for the five different positional groups, the first part of this thesisdemonstrated greater high-intensity activity in European cup when compared to the TOP14 rugby unioncompetition; with position-dependent variations in the frequency of repeated high-intensity efforts and the relativedistance of high-speed movements in forwards. A decrease in high-intensity movement parameters was observedduring the first and second halves of a competitive rugby union match. Indeed, the decrease in high-intensitymovements was earlier in forwards and outside backs who peaked in high-intensity accelerations between the lasttwo periods of the game, while backs were able to maintain their high-intensity activity throughout the match.Collectively, the capacity for a player to repeat high-intensity efforts during a rugby union game varied by thelevel of competition and was influenced by the onset of fatigue. In this context, the second part of this thesis was to conduct a repeated-sprint training in hypoxia. Hypoxia was induced by voluntary hypoventilation at low lungvolume. This training protocol has largely improved the repeated-sprint ability performance in highly-trainedrugby union players after seven training sessions of hypoventilation, whereas it was unaltered in the controlnormoxic group. Such training demands in rugby union (characterised by repeated high-intensity efforts indynamic (running) and static (weightlifting, fighting)) have a specific impact on left ventricular remodelling. Thelast part of this thesis, using 2D-speckle-tracking resting echocardiography, demonstrated that LV hypertrophywas greater in forwards when compared to backs and to control group. Systolic function remained unchanged, butdiastolic function was altered, mainly in forwards, with an increase in filling pressures and a decrease in leftventricular relaxation. Finally, left ventricular twisting was similar while rugby union players exhibited lowerapical and higher basal rotations velocities compared to controls. Collectively, this CIFRE research programprovided new data in activity analysis and training methods that are widely applicable to a range of rugby unionprograms and data on left ventricular morphology, function and mechanics for the clinician.
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Valor prognóstico de provas funcionais na evolução tardia de pacientes com infarto agudo do miocárdio tratados com angioplastia coronária transluminal percutânea primária com implante de stent / Prognostic value of non-invasive functional tests during the follow-up of acute myocardial infarction treated with primary coronary stentingBüchler, Rica Dodo Delmar 25 June 2007 (has links)
Introdução: A angioplastia primária associada ao implante de stent é o tratamento de escolha no infarto agudo do miocárdio. Discute-se o valor de provas funcionais na abordagem de reestenose coronária, bem como o tempo ideal para sua realização. O objetivo deste estudo foi avaliar a importância do teste ergométrico, da cintilografia de perfusão miocárdica e do ecocardiograma bidimensional em repouso, no diagnóstico de reestenose em pacientes tratados durante as primeiras 12 horas de evolução do infarto com supra desnivelamento do segmento ST. Métodos: No período de agosto de 2003 a janeiro de 2006 foram selecionados 64 pacientes tratados com angioplastia primária e implante de stent nas primeiras 12 horas de evolução do primeiro infarto. Os pacientes realizaram ecocardiograma bidimensional em repouso, teste ergométrico com adição de derivações precordiais direitas e cintilografia de perfusão miocárdica com captação tomográfica (SPECT) sincronizada ao ECG (GATED SPECT), seis semanas (etapa1), seis meses (etapa 2) e um ano (etapa3) após a angioplastia primária. Foi realizado reestudo angiográfico no sexto mês de evolução. Resultados: A idade média foi 56,2 ±10,2 anos; 53 pacientes eram do sexo masculino. Doença uniarterial > = 50% foi observada em 46,9% dos casos. A artéria descendente anterior foi tratada em 48,4% dos pacientes, artéria coronária direita em 34,4%, artéria circunflexa em 10,9%, tronco de coronária esquerda em 3,1%,grande ramo diagonal em 1,6% e ponte safena em 1,6%. Reestenose angiográfica ocorreu em 28.8% dos 59 casos submetidos a reestudo. A fração de ejeção do ventrículo esquerdo ao ecocardiograma foi em média: 0,55 (etapa 1), 0,55 (etapa 2) e 0,56 (etapa 3). Observou-se diferença entre a fração de ejeção dos pacientes com e sem reestenose um ano após o procedimento (p=0,003). Sensibilidade, especificidade, valor preditivo positivo, valor preditivo negativo e acurácia do teste ergométrico foram respectivamente: 53,3%, 69% , 38,1%, 80,6% e 64,9% na etapa 1 (p=0,123); 54,5%, 70,7%, 33,3%, 85,3% e 67,3% na etapa 2(p=0,159) e 38,5%, 66,7%, 27,8% ,76,5% e 59,6% na etapa 3 (p=0,747). A adição de derivações precordiais direitas não elevou os índices de sensibilidade em nenhuma das etapas. Os valores de sensibilidade, especificidade, valor preditivo positivo, valor preditivo negativo e acurácía obtidos após a cintilografia de perfusão miocárdica com MIBI, quando considerada a diferença de escores entre esforço e repouso >2, foram respectivamente 40%,78,6%, 40%, 78,6% e 68,4% na etapa1(p=0,185); 54,5%,87,8%,54,5%,87,8% e 80,8% na etapa 2 (p=0,006) e 25%,91,7%,50%,78,6% e 75% na etapa 3(p=0,156). Quando considerada a diferença de escores >4 os valores foram respectivamente: 13,3%,88,1%,28,6% ,74% e 68,4% na etapa 1(p>0,999); 36,4%,95,1%,66,7%,84,8% e 82,7% na etapa 2 (p=0,014) e 8,3%,94,4 %,33,3%,75,6% e 72,9 % na etapa 3 (p >0,999). Conclusões: O teste ergométrico não permitiu discriminar reestenose na população estudada, em nenhuma das etapas durante a evolução. A cintilografia miocárdica realizada seis meses após o infarto apresentou associação com reestenose. Os pacientes com reestenose apresentaram menores valores de fração de ejeção do ventrículo esquerdo um ano após a angioplastia primária, por avaliação ecocardiográfica. / Primary coronary angioplasty and stenting during acute myocardial infarction is the first treatment choice. Non-invasive testings have been used in the diagnosis of restenosis but its efficacy and time to be performed have to be determined. The purpose of this study was to evaluate exercise treadmill test, myocardial perfusion imaging and rest two-dimensional echocardiogram in the diagnosis of restenosis in patients treated during the first 12 hours of STelevation myocardial infarction.Methods: From August 2003 to January 2006, 64 patients were selected after primary coronary angioplasty and stenting. Rest two- dimensional echocardiogram, exercise treadmill test associated to right precordial leads and myocardial perfusion imaging according to GATED-SPECT were performed 6 weeks (step 1), 6 months (step 2) and one year (step 3) after the procedure.Coronary angiography was performed during the sixth month of follow-up.Results : Mean age was 56.2 ± 10.2 years; 53 patients were male. Single vessel disease > = 50% was observed in 46.9% of patients. The left anterior descending coronary artery was treated in 48.4%, the right coronary artery in 34.4%, the left circumflex in 10.9%, the left main coronary artery in 3.1%, a large diagonal branch in 1.6% and saphenous vein graft in 1.6% of the cases. Angiographic restenosis occurred in 28.8% from 59 patients submitted to coronary angiography. Mean left ventricular ejection fraction observed during rest two-dimensional echocardiogram was: 0.55 (step 1), 0.55 (step 2) and 0.56 (step 3). It was observed in patients with and without restenosis a significant difference in the left ventricular ejection fraction one year after the procedure (p= 0.003). Exercise treadmill test sensitivity, specificity, positive and negative predictive values and accuracy were respectively: 53.3%, 69%, 38.1%, 80.6% and 64.9% in step 1(p=0.123); 54.5%, 70.7%, 33.3%, 85.3% and 67.3% in step 2 (p=0.159) and 38.5%, 66.7%, 27.8%, 76.5% and 59.6% in step 3 (p=0.747). Right precordial leads did not show any additional significance. Sensitivity, specificity, positive and negative predictive values and accuracy during myocardial perfusion imaging when considering summed difference score > 2 were respectively: 40%, 78.6%, 40%, 78.6% and 68.4% in step 1(p=0.185); 54.5%, 87.8%, 54.5%,87.8% and 80.8% in step 2(p=0.006) and 25%, 91.7%, 50%, 78.6% and 75% in step 3(p=0.156). When considering summed difference score > 4 they were respectively: 13.3%, 88.1%, 28.6%, 74% and 68.4% in step 1(p> 0.999); 36.4%, 95.1%,66.7%, 84.8% and 82.7% in step 2 (p=0.014) and 8.3%, 94.4%, 33.3%, 75.6% and 72.9% in step 3(p> 0.999). Conclusions: Exercise treadmill test did not allow to discriminate restenosis in this population in all steps.Myocardial perfusion imaging performed 6 months after acute myocardial infarction was associated to restenosis. Patients with restenosis showed lower left ventricular ejection fraction one year after acute myocardial infarction by rest two-dimensional echocardiogram.
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Cirurgia torácica vídeo-assistida para a ablação da fibrilação atrial por radiofreqüência bipolar: exeqüibilidade, segurança e resultados iniciais / Video-assisted thoracic surgery for atrial fibrillation ablation using bipolar radiofrequency: Feasibility, Safety and initial resultsColafranceschi, Alexandre Siciliano 06 October 2008 (has links)
INTRODUÇÃO: A prevalência da fibrilação atrial, os gastos com o sistema de saúde e a elevada morbidade e mortalidade associados a ela, têm justificado a procura por um melhor entendimento de suas bases fisiopatológicas e por novas abordagens terapêuticas. O objetivo deste manuscrito é avaliar a exeqüibilidade, a segurança e os resultados em três meses da cirurgia vídeo-assistida para a ablação da fibrilação atrial com radiofreqüência bipolar. MÉTODOS: Dez pacientes (90% homens) com fibrilação atrial sintomática e refratária à terapia medicamentosa foram submetidos ao procedimento cirúrgico proposto no Instituto Nacional de Cardiologia, Rio de Janeiro, no período de Maio 2007 a Maio de 2008. Foram analisadas variáveis de peri e pós-operatório. Além da avaliação clínica dos sintomas, todos os pacientes foram submetidos a um ecocardiograma e Holter de 24horas antes e três meses após a cirurgia. Realizou-se também uma angiotomografia de veias pulmonares no terceiro mês de seguimento pós-operatório. RESULTADOS: O procedimento foi realizado conforme planejado em todos os pacientes. Cem por cento das veias pulmonares direitas e 90% das esquerdas tiveram o isolamento elétrico confirmado. Não houve lesão iatrogênica de estruturas intra-torácicas ou óbitos. Dois pacientes apresentaram pneumonia pós-operatória e longo tempo de permanência hospitalar no início da experiência clínica. Nove dos dez pacientes saíram do centro cirúrgico em ritmo sinusal. Houve uma recorrência da fibrilação atrial em três meses (11,1%). No total, 80% dos pacientes estão livres de fibrilação atrial em três meses. Houve melhora significativa da função diastólica avaliada ecocardiograficamente pela relação E/E após a cirurgia (9,0 ± 2,23 para 7,7 ± 1,07; p=0,042) que se associa a uma melhora dos sintomas de insuficiência cardíaca classe funcional da New York Heart Association (2,4 ± 0,5 para 1,6 ± 0,7; p=0,011). Não houve evidência de estenose de veias pulmonares à angiotomografia nesta série. CONCLUSÃO: A cirurgia torácica vídeo-assistida para o tratamento da fibrilação atrial é exeqüível e segura mas a incorporação desta nova técnica à prática clínica requer uma curva de aprendizado da equipe envolvida. A melhora dos sintomas de insuficiência cardíaca está relacionada à melhora da função diastólica do ventrículo esquerdo / BACKGROUND: Atrial fibrillation prevalence, its health system cost and the high morbidity and mortality associated with it have justified the search for a better understanding of its pathophysiology and new therapeutic management. The objective of this study was to assess the feasibility, the safety and the three months results of the video-assisted thoracoscopic surgery for the ablation of atrial fibrillation using bipolar radiofrequency. METHODS: Ten patients (90% male) with symptomatic and refractory atrial fibrillation underwent the proposed surgical procedure at the National Institute of Cardiology, Rio de Janeiro, Brazil, from May 2007 to May 2008. Peri and post-operative data were collected for analysis. Besides clinical evaluation, all patients have been submitted to an echocardiogram and a 24h Holter monitoring before and three months after the procedure. A pulmonary veins angiotomography was also performed three months after surgery. RESULTS: The surgical procedure was done as planned in all patients and 100% of the right pulmonary veins were isolated. Ninety per cent of the left pulmonary veins were confirmed to be electrically isolated. There was no surgical injury to any intra thoracic organ or death in this series. Two patients had post-operative pneumonia that required prolonged in hospital stay early in the experience. Nine of ten patients were in sinus rhythm just after surgery. There was one recurrence of atrial fibrillation within the three months follow up (11,1%). In general, eighty per cent (80%) of the patients are free of atrial fibrillation three months after surgery. There was a significant improvement in diastolic function measured by the relation E/E on the echocardiogram before and after the procedure (9,0 ± 2,23 to 7,7 ± 1,07; p=0,042). This was associated to an improvement of heart failure symptoms of New York Heart Association (2,4 ± 0,5 to 1,6 ± 0,7; p=0,011). There was no pulmonary vein stenosis in this cohort. CONCLUSIONS: Video-assisted thoracoscopic surgery for the treatment of atrial fibrillation is feasible and safe although it requires a learning curve to incorporate this new technique to clinical practice. The improvement on heart failure symptoms is associated to an improvement on diastolic left ventricular function
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Avaliação ecocardiográfica da sincronia mecânica como marcador de eventos em portadores de insuficiência cardíaca. / Echocardiographic assessment of mechanical synchrony as predictor of events in patients with heart failure.Barretto, Rodrigo Bellio de Mattos 20 April 2012 (has links)
A ecocardiografia é um importante exame no diagnóstico de insuficiência cardíaca, avaliando as funções, sistólica e diastólica, comprometidas nesta síndrome. Pacientes com insuficiência cardíaca apresentando disfunção sistólica esquerda constituem uma população com alta morbidade e mortalidade, tendo sido descritos diversos parâmetros ecocardiográficos marcadores de prognóstico. Recentemente, desenvolveram-se metodologias que possibilitam avaliar a sincronia mecânica do coração que se apresenta especialmente comprometida nesta população. No entanto, o valor destas medidas em estimar o risco de eventos clínicos adversos é incerto. O objetivo deste estudo foi o de testar se estas medidas ecocardiográficas podem constituir marcadores de eventos cardíacos adversos em pacientes clinicamente estáveis com insuficiência cardíaca e disfunção sistólica esquerda. Duzentos e sete pacientes encaminhados consecutivamente dos ambulatórios de Insuficiência Cardíaca e Miocardiopatias, em condição clínica estável e com medicação otimizada realizaram um ecocardiograma, coletando-se nesta data: dados clínicos, eletrocardiográficos e amostras de sangue. No ecocardiograma, avaliaram-se além das medidas convencionais, aquelas que descrevem a sincronia: atrial esquerda, atrioventricular, interventricular, intraventriculares diastólica e sistólica, esta última por cinco metodologias distintas. Acompanharam-se estes pacientes por 1,5±0.9 anos. Por meio da regressão logística de Cox, analisaram-se estes dados como marcadores dependentes ou independentes de desfecho principal (óbito ou transplante cardíaco) e secundário (óbito, transplante cardíaco ou hospitalização por descompensação da insuficiência cardíaca). As características e frequências mais marcantes do grupo foram: sexo masculino - 64%, idade 58±13 anos, Classe funcional II/III - NYHA 70%, doença arterial coronariana 40%, uso de inibidores de enzima de conversão ou bloqueador dos receptores de angiotensina II 93%, uso de betabloqueadores 90%, intervalo QRS 148±31 ms, bloqueio de ramo esquerdo 57%, diâmetro diastólico do ventrículo esquerdo 72±9 mm, fração de ejeção do ventrículo esquerdo 30±5 %, disfunção diastólica grau III ou IV 46%, insuficiência mitral mais que discreta 19%. Nenhuma variável ecocardiográfica que avalia a sincronia mecânica foi marcadora destes eventos. Na análise multivariada pelo modelo de Cox, as variáveis associadas ao desfecho primário foram: sexo feminino HR, 0,14 (p=0.01), Classe funcional III - NYHA, HR 14,64 (p<0.01), índice de massa cardíaca cada 10 g, HR 1,16 (p<0,01), fração de ejeção do ventrículo esquerdo cada 5%, HR 0,44 (<0,01) e a fração de esvaziamento ativo do átrio esquerdo cada 10%, HR 0,38 (p<0,01). Para o desfecho secundário, as variáveis que se associaram foram: Classe funcional III - NYHA, HR 8,50 (p<0,01), índice de massa cardíaca cada 10 g, HR 1,06 (p=0,04), fração de esvaziamento ativo do átrio esquerdo cada 10%, HR 0,69 (p=0,01) e a integral do Doppler da via de saída do ventrículo esquerdo cada 5 cm, HR 0,65 (p=0,03). Os resultados deste estudo indicam que as medidas ecocardiográficas de sincronia cardíaca não se apresentam como marcadores prognósticos de pacientes clinicamente estáveis, portadores de insuficiência cardíaca com disfunção sistólica esquerda. / Echocardiography is a diagnostic tool to establish clinical diagnosis of heart failure, accurately evaluating heart\'s dysfunction, systolic and/or diastolic, existing in this syndrome. Heart failure patients with systolic left ventricular dysfunction constitute a population with high morbidity and mortality, have being described several echocardiographic prognostic factors. Recently, new methodologies enable the evaluation of mechanical synchrony of the heart that compromises frequently this particular population. However, the value of these measurements to estimate risk of adverse clinical events in such patients is uncertain. The purpose of this study was to test whether these echocardiographic measurements can predict cardiac adverse events in heart failure patients, clinically stable, with left ventricular systolic dysfunction. Two hundred and seven patients referred consecutively from outpatient heart failure clinics, in stable clinical condition, with optimized medication did an echocardiogram collecting also clinical, electrocardiographic data and blood samples. There were evaluated in addition to conventional echocardiographic measurements, those that describe the various types of synchrony: left atrial, atriovenricular, interventricular, intraventricular diastolic and systolic, the latter by five distinct methods. The follow up was 1.5 ± 0.9 years. By Cox regression, we analyzed if these data were dependent or independent predictors of primary (death or cardiac transplantation) and secondary outcome (death, heart transplantation or hospitalization for heart failure decompensation). The most remarkable features and frequencies of this group were: male gender- 64%, age 58 ± 13 years, functional class II / III - NYHA 70%, known coronary artery disease 40%, use of converting enzyme inhibitor or receptor blocker angiotensin II 93%, beta-blockers 90%, QRS interval 148 ± 31 ms, left bundle branch block 57%, left ventricular diastolic diameter 72 ± 9 mm, left ventricular ejection fraction 30 ± 5%, diastolic dysfunction grade III or IV 46%, mitral regurgitation - more than mild 19%. None of the echocardiographic variables that evaluate mechanical synchrony predicted these events. On Cox multivariate regression, the variables associated to the primary outcome were: female gender, HR 0.14 (p = 0.01), functional class III - NYHA, HR 14.64 (p <0.01), cardiac mass index - every 10 g, HR 1.16 (p <0.01), ejection fraction, left ventricular - every 5 %, HR 0.44 (p <0.01) and left atrial active emptying fraction - every 10%, HR 0.38 (p <0.01). For the secondary outcome, the variables associated were: functional class III - NYHA, HR 8.50 (p <0.01), cardiac mass index - every 10 g, HR 1, 06 (p = 0.04), left atrial active emptying fraction - every 10%, HR 0.69 (p = 0.01) and the integral of left ventricle outflow Doppler - every 5 cm, HR 0.65 (p= 0.03). The results of this study indicate that echocardiographic measurements of cardiac synchrony are not predictors of cardiac events of clinically stable heart failure patients with systolic left ventricular dysfunction.
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Ecocardiografia em terapia intensiva: avaliação de treinamento voltado para intensivistas e emergencistas pediátricos / Focused cardiac ultrasound: a training course for pediatric intensivists and emergency physiciansGonçalves, Heloisa Amaral Gaspar 08 August 2014 (has links)
Introdução: O exame ecocardiográfico direcionado realizado por médicos intensivistas e emergencistas pode ser uma ferramenta valiosa para a avaliação e manejo do estado hemodinâmico de crianças gravemente doentes. O objetivo do presente estudo foi avaliar o aprendizado de médicos pediatras de setores de emergência submetidos a um programa de treinamento teórico e prático supervisionado em ecocardiografia de emergência. Método: Treinamento com componente teórico e prático foi realizado por dois ecocardiografistas experientes e teve como alvo 16 médicos intensivistas/emergencistas pediátricos. O programa incluiu análises qualitativas de função do ventrículo esquerdo (VE) e ventrículo direito (VD), avaliação de derrame pericárdio/tamponamento cardíaco, regurgitação valvar e avaliação de variação respiratória de veia cava inferior através do índice de distensibilidade da veia cava inferior (dVCI), além de medidas objetivas de fração de ejeção (FE) e índice cardíaco (IC). As aulas práticas foram realizadas na unidade de terapia intensiva pediátrica do Instituto da Criança do Hospital das Clínicas e cada aluno realizou 24 exames direcionados de ecocardiograma durante o treinamento. Os alunos foram avaliados de forma prática, sendo os resultados dos exames realizados pelos alunos comparados com os exames realizados pelo ecocardiografista experiente. As avaliações ocorreram após 8, 16 e 24 exames práticos. Resultados: A taxa de concordância entre o aluno e ecocardiografista na análise subjetiva da função do VE foi de 81,3% na primeira avaliação, 96,9% na segunda avaliação e 100% na terceira avaliação (p < 0,001). Para o dVCI, observou-se uma concordância de 46,7% na primeira avaliação, 90,3% na segunda avaliação e 87,5% na terceira avaliação (p = 0,004). As médias das diferenças entre os alunos e ecocardiografista na medida de fração de ejeção e índice cardíaco foram 7% e 0,56 L/min/m2, respectivamente, após a terceira etapa do treinamento. Conclusões: O treinamento proposto demonstrou ser suficiente para capacitar os médicos pediatras na análise de função do VE de forma subjetiva e também para as medidas objetivas de dVCI, FE e IC. Este modelo de curso pode facilitar o desenho de outros treinamentos médicos em ecocardiografia de emergência e auxiliar na implementação destes cursos de forma isolada ou inserido em programas de residência médica, gerando melhoria nas habilidades técnicas dos médicos dos setores de emergência e desta forma culminando com melhor cuidado dos pacientes criticamente enfermos / Background: Focused echocardiographic examinations performed by intensivists and emergency room physicians can be a valuable tool for diagnosing and managing the hemodynamic status of critically ill children. The aim of this study was to evaluate the learning curve achieved using a theoretical and practical training program designed to enable pediatric intensivists and emergency physicians to conduct targeted echocardiograms. Methods: Theoretical and practical training sessions were conducted with 16 pediatric intensivist/emergency room physicians. The program included qualitative analyses of the left ventricular (LV) and right ventricular (RV) functions, evaluation of pericardial effusion/cardiac tamponade and valvular regurgitation and measurements of the distensibility index of the inferior vena cava (dIVC), ejection fraction (EF) and cardiac index (CI). The practical training sessions were conducted in the intensive care unit; each student performed 24 echocardiograms. The students in training were evaluated in a practical manner, and the results were compared with the corresponding examinations performed by experienced echocardiographer. The evaluations occurred after 8, 16 and 24 practical examinations. Results: The concordance rates between the students and echocardiographers in the subjective analysis of the LV function were 81.3% at the first evaluation, 96.9% at the second evaluation and 100% at the third evaluation (p < 0.001). For the dIVC, we observed a concordance of 46.7% at the first evaluation, 90.3% at the second evaluation and 87.5% at the third evaluation (p=0.004). The means of the differences between the students\' and echocardiographers\' measurements of the EF and CI were 7% and 0.56 L/min/m2, respectively, after the third stage of training. Conclusions: The proposed training was demonstrated to be sufficient for enabling pediatric physicians to analyze subjective LV function and to measure dIVC, EF and CI. This training course should facilitate the design of other echocardiography training courses that could be implemented in medical residency programs to improve these physicians\' technical skills and the care of critically ill patients
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