Avaliação eletrocardiográfica em cães submetidos à pneumonectomia direita

O propósito das ressecções pulmonares em cães e gatos, quer sejam por lobectomia ou pneumonectomia, é a cura ou paliação de processos broncopulmonares sempre que os meios conservadores de tratamento clínico sejam considerados ineficientes. Tendo em vista as significativas alterações resultantes da pneumonectomia, novos estudos experimentais devem ser feitos para avaliar as vantagens dessa intervenção cirúrgica e determinar a maneira como aplicá-la com segurança. O presente estudo tem como objetivo avaliar as alterações eletrocardiográficas em dez cães adultos de ambos os sexos, sem raça definida, com 10-30 kg, submetidos à pneumonectomia direita. Foram avaliados diariamente os parâmetros clínicos de cada cão e as alterações em todas as derivações do eletrocardiograma. Todos os cães apresentaram um bom desenlace pós-operatório. Apenas um cão apresentou alteração de relevância clínica, um caso de complexos ventriculares prematuros, possivelmente decorrente da parada cardiorrespiratória, que foi revertido com sucesso. Houve diminuição da amplitude dos complexos QRS nos primeiros 14 dias, retornado ao normal após 60 dias de pós-operatórioThe purpose for using lobectomy or pneumonectomy in dogs and cats, is to cure or palliate of bronchopulmonary diseases whenever conservative clinical treatment proves ineffective. Considering the marked changes caused by pneumonectomy, new experimental studies have to be done to assess the advantages of this surgical intervention allow its performance without any risk. The aim of the current study was to evaluate the electrocardiographic alterations in ten adult mongrel dogs of both sexes with between 10 and 30 Kg that were submitted to right pneumonectomy. The clinical parameters of the dogs were evaluated in a daily basis and the alterations in every electrocardiogram derivation were recorded. All dogs presented a good post-operative outcome. In most cases there were no electrocardiographic alterations; when these alterations were observed they were of no clinical significance and included premature ventricular complexes in one dog, most likely resulting from a cardiorespiratory arrest that was reverted to successfully, and a decreased width in the QRS complex amplitude on the first 0-14 days post surgery which returned to normal after sixty days post surger

Long-term treatment with deferiprone enhances left ventricular ejection function when compared to deferoxamine in patients with thalassemia major

Transfusion and iron chelation treatment have significantly reduced morbidity and improved survival of patients with thalassemia major. However, cardiac disease continues to be the most common cause of death. We report the left-ventricular ejection fraction, determined by echocardiography, in one hundred sixtyeight patients with thalassemia major followed for at least 5 years who received continuous monotherapy with deferoxamine (N = 108) or deferiprone (N = 60). The statistical analysis, using the generalized estimating equations model, indicated that the group treated with deferiprone had a significantly better left-ventricular ejection fraction than did those treated with deferoxamine (coefficient 0.97; 95% CI 0.37; 1.6, p = 0.002). The heart may be particularly sensitive to iron-induced mitochondrial damage because of the large number of mitochondria and its low level of antioxidants. Deferiprone, because of its lower molecular weight, might cross into heart mitochondria more efficiently, improving their activity and, thereby, myocardial cell function. Our findings indicate that the long-term administration of deferiprone significantly enhances left-ventricular function over time in comparison with deferoxamine treatment. However, because of limitations related to the design of this study, these findings should be confirmed in a prospective, randomized clinical trial

Morphophysiogenetic characterization of wild poinsettia biotypes with low resistance to glyphosate.

The objective of this work was to compare wild poinsettia (Euphorbia heterophylla) biotypes as to their morphological characteristics, as well as to determine their genetic similarity in the state of Rio Grande do Sul, Brazil, and to confront the light compensation point of susceptible biotypes and of biotypes with low-resistance level to glyphosate. Besides the morphology analysis, the study included the genetic characterization, by AFLP, of susceptible (GR50 = 58.65 g ha-1 a.e.) biotypes and of biotypes with low resistance (GR50 = 310.36 g ha-1 a.e.) to glyphosate. The competitive ability of the biotypes was inferred according to their light compensation point. The observed morphological characteristics do not allow to differentiate biotypes as to their geographical location, or their resistance level to glyphosate. The genetic analysis identified low genetic diversity among the 15 tested biotypes, with a large amount of subgroups. The biotypes with low resistance formed an isolated group. The susceptible biotypes showed the lowest values of light compensation point and, possibly, they have a greater competitive ability under low-luminosity conditions. The evaluated characteristics do not enable to differentiate genotypes with different levels of glyphosate resistance.Título em português: Caracterização morfofisiogenética de biótipos de leiteira com baixa resistência ao glifosato

Left atrial function after atrial fibrillation cryoablation concomitant to minimally invasive mitral valve repair: A pilot study on long-term results and clinical implications

Background and Objectives: Surgical atrial fibrillation (AF) ablation concomitant to minimally invasive mitral valve repair has been proven to offer improved short- and long-term sinus rhythm (SR) maintenance compared to mitral valve surgery only. The objective of the present study was to explore, by thorough echocardiographic assessment, long-term morphological and functional left atrial (LA) outcomes after this combined surgical procedure. Materials and Methods: From October 2006 to November 2015, 48 patients underwent minimally invasive mitral valve repair and concomitant surgical AF cryoablation. Results: After 3.8 ± 2.2 years, 30 (71.4%) of those completing the follow-up (n = 42, 87.5%) presented SR. During follow-up, four (9.5%) patients suffered from cerebrovascular accidents and two of these subjects had a long-standing persistent AF relapse and were in AF at the time of the event, while the other two were in SR. An echocardiographic study focused on LA characteristics was performed in 29 patients (69.0%). Atrial morphology and function (e.g., maximal LA volume indexed to body surface area and total LA emptying fraction derived from volumes) in patients with stable SR (60.6 ± 13.1 mL/mq and 25.1 ± 7.3%) were significantly better than in those with AF relapses (76.8 ± 16.2 mL/mq and 17.5 ± 7.4%; respectively, p = 0.008 and p = 0.015). At follow-up, patients who suffered from ischemic cerebral events had maximal LA volume indexed to body surface area 61 ± 17.8 mL/mq, with total LA emptying fraction derived from volumes 23.6 ± 13.7%; patients with strokes in SR showed very enlarged LA volume (>70 mL/mq). Conclusions: AF cryoablation concomitant with minimally invasive mitral valve repair provides a high rate of SR maintenance and this relates to improved long-term morphological and functional LA outcomes. Further prospective studies are needed to define the cut-off values determining an increase in the risk for thromboembolic complications in patients with restored stable SR

بررسی عوارض قلبی در بيماران مبتلا به تالاسمی ماژور در کاشان در سالهای 1378 لغايت 1379

با توجه به شيوع تالاسمی ماژور در کشور ما و با در نظر گرفتن اينکه عوارض قلبی ناشی از اضافه بار آهن، از مهمترين علل مرگ و مير در اين بيماران می‌باشد، بر آن شديم تا عوارض قلبی را در بيماران مبتلا به تالاسمی ماژور در شهر کاشان در طی سالهای 1378 تا 1379 بررسی نمائيم. بايد به اين نکته اشاره شود که مطالعه مشابهی تاکنون در اين منطقه انجام نشده بود. اين پژوهش به روش توصيفی و آينده‌نگر، روی 17 بيمار مبتلا به تالاسمی ماژور انجام شد. تمام بيماران، مورد بررسی کامل و غيرتهاجمی قلبی عروقی ( شرح حال ، معاينه فيزيکی، الکتروکارديوگرافی( ECG )، پرتونگاری قفسه سينه ( CXR ) و اکوکارديوگرافی کامل 2 بعدی و داپلر M-Mode رنگی) قرار گرفتند. در گروه شاهد، اندازه گيری فشار خون شريانی و بررسی اکوکارديوگرافيک کنش ( Function ) دياستولی در 17 فرد سالم که از نظر سن و جنس با گروه بيماران مشابه بودند، انجام شد. داده‌های بدست آمده ثبت و انحراف معيار تعيين شد و P value کمتر از 05/0 معنی‌دار محسوب گرديد. از 17 بيمار، 11 نفر مرد و 6 نفر زن بودند که سن آنها بين 18 ماه تا 25 سال ( با ميانگين 14 سال ) بود در شرح حال، 88% بيماران از ضعف و خستگی شکايت داشتند. در تمام بيماران فشار خون شريانی بين منحنی 5% تا 25% برای قد ، جنس و سن قرار داشت. ECG و اندازه قلب در CXR به ترتيب در 82% و 76% بيماران طبيعی بود. يافته‌های غير طبيعی در ECG عبارت بودند از هيپرتروفی بطن چپ در 2 بيمار و بلوک دهليزی بطنی درجه يک در 1 بيمار( که در ECG 6 ماه قبل وجود نداشت). در اکوکارديوگرافی، دژکنشی( dysfunction ) دياستولی و سيستولی به ترتيب در 82% و 11% از بيماران ملاحظه گرديد. دژکنشی دياستولی، پيش از دژکنشی سيستولی در بيماران مبتلا به تالاسمی ماژور رخ می‌دهد. ECG و پرتونگاری قفسه سينه ابزار حساسی برای شناسايی زودرس اختلال در کنش دياستولی بيماران نمی‌باشند، اما اکوکارديوگرافی بهترين ابزار غير تهاجمی جهت بررسی کنش بطنها بويژه کنش دياستولی می‌باشد و انجام آن برای شناسايی زودرس عوارض قلبی در اين بيماران توصيه می‌گردد

Age, Sex and Body Weight Related Echocardiographic Parameters of Clinically Healthy New Zealand White Rabbits

Background: Echocardiography provides useful additional information on cardiac dimensions including heart wall and dimension of the ventricles, atria and conditions. Rabbits have been diagnosed with cardiac diseases, and an understanding of the animals’ cardiac chamber dimensions is vital in assessing the diseases’ severity and prognoses. Changes in cardiac dimensions due to age related and body weight were determined at different animals. The increased incidence of congenital cardiovascular anomalies makes it essential to establish the diagnosis at an early age. The aims of this study 1) establish normal values for the commonly used two-dimensional (2D) M-mode parameters using pre anaesthetics and 2) evaluate the effects of age, sex, and body weight on echocardiographic parameters in clinically healthy New Zealand rabbits.Materials, Methods & Results: In this study we used 49 New Zealand white rabbits (25 male, 24 female) all reared under the same conditions. A general physical and clinical examination including complete blood count was performed for each animal. Body surface area was calculated as BSA= 0.00718 × Height 0.725 × Weight 0.425. Rabbits were sedated with midazolam before echocardiographic examination was performed. Echocardiographic examination was performed using a DC 6-Vet® (Mindray, PRC) ultrasonographic device equipped with a micro-convex 8 MHz probe. Right parasternal short-axis view, B-mode and two-dimensional guided M-mode parameters were measured. Echocardiographic measurements were performed using leading-edge-to-leading-edge conventions outlined by the American Society of Echocardiography. Statistical analyses were employed using the SPSS 19.0 program. Sex had no significant effect on the measured echocardiographic parameters except in the case of interventricular septum thickness in diastole values of the three-month-old rabbits. The increase in the left ventricular systolic and diastolic diameters, E- point to septal separation, diastolic aortic root parameters for the three, six, and nine-month-old groups indicated persistent anatomic heart enlargement. However, it was also discovered that the fractional shortening percentage of the left ventricle and diastolic diameters of left atrium:aortic root  were unrelated to age and weight.Discussion: New Zealand rabbits are an important model for cardiovascular research, mainly as they are small and relatively inexpensive however large enough to allow anatomical and physiological experiments. Different ages and sizes of New Zealand rabbits showed no significant difference in fractional shortening despite heart enlargement. The ejection fraciton, which can be calculated from the left ventricular dimensions via M-mode echocardiography, is another parameter of cardiac function. Our echocardiograph calculated the ejection fraction automatically using the Teicholz formula. It was further observed that three-month-old rabbits ejection fraction of the left ventricle was higher than that of the six and nine-month-old rabbits. This might indicate the necessity of periodical analysis of echocardiographic parameters. Transthoracic echocardiography can be considered an applicable method for cardiovascular research using a growing rabbit animal model after appropriate adjustments for age, sex and body size. These findings give a better understanding of the functional changes investigated by echocardiography in rabbits and will be helpful when evaluating echocardiographic data in small experimental animals

Cardiopatías congénitas en el perro : conducto arterioso persistente, estenosis pulmonar y estenosis aórtica

En el presente artículo se describen los hallazgos clínicos, radiológicos, electrocardiográficos y ecográficos de las principales cardiopatías congénitas en el perro de acuerdo con una serie de casos clínicosClinical signs and radiological, electro and echocardiographic findings of the main congenital heart diseases in the dog are described in this paper based on c1inicalcases

Quantification of cardiac blood flow by Doppler technique

The investigations described in this thesis started as part of the research program of the divisions of pediatric cardiology of the Universities of Arizona and California (San Diego). The investigations were part of an ongoing project designed by D.J. Sahn and L.M. Valdes-Cruz. This project was initiated to implement Doppler techniques in the daily practice of pediatric cardiology. New developments in medical technology made the Doppler techniques integrated into sophisticated two-dimensional echocardiographic equipment available to the clinician. In order to extend the use of the Doppler equipment beyond that of a sophisticated stethoscope and to enter the era of quantitative two-dimensional Doppler echocardiography it was felt that clinical validation of simple quantification approaches was necessary. As an initial approach animal studies were performed. Open chest dog models were created where simultaneously with the Doppler studies electromagnetic flow measurements and pressure gradients could be obtained. The results of both techniques were compared and a good correlation was obtained. Twodimensional Doppler echocardiographic quantifications were subsequently performed in patients with a variety of diseases during cardiac catheterization to validate the results in a clinical setting. The blood flow calculations over the mitral valve orifice and the development of the mitral valve flow method, including the mean to maximal index of the mitral valve, were performed by D. Fisher. Measurement of shunt size at atrial and ventricular level of the left-to- right type was validated by S. Horowitz. The measurement of extracardiac type left-to-right shunting such as in the persistent ductus arteriosus, of the tricuspid valve flow and a simplified approach to measurement of mitral valve flow will be described in this thesis. The tricuspid valve method and the simplified mitral valve methods are both studied in patients during cardiac catheterization for validation purposes and were subsequently used for calculation of flows in the human fetus during the second and third trimester of pregnancies. This thesis was completed by the study of the reproducibility of the previously described techniques in human subjects. This part of the investigation was performed at the Thoraxcenter in Rotterdam and supported by the Interuniversity Cardiology Institute of the Netherlands. This investigation was supervised by Professor Born and Professor Roeland!. H.Rijsterborgh performed the statistical analysi