Estudo retrospectivo dos achados cardiorrespiratórios e laboratoriais de cães atendidos para avaliação pré-operatória em um serviço de cardiologia e doenças respiratórias (2017-2021) / Retrospective study of cardiorespiratory and laboratory findings in dogs treated for preoperative evaluation in a cardiology and respiratory disease service (2017-2021)

Os cães idosos são acometidos com frequência por enfermidades no sistema cardiovascular e respiratório, estando muita das vezes assintomáticos até terem indicação para algum procedimento cirúrgico que requer a avaliação pré-operatória, momento este que muitos achados clínicos poderão ser detectados, ao ponto da necessidade de tratamento prévio à intervenção cirúrgica. Diante disso, o trabalho tem por objetivo detectar as principais manifestações cardiorrespiratórias e sua correlação aos dados encontrados nos exames complementares e informações epidemiológicas de 138 cães atendidos em um serviço especializado em cardiologia e doenças respiratórias, no período de 2017 a 2021, para fins de risco cirúrgico. Foi possível observar maior predominância de animais idosos, de pequeno porte e do sexo feminino. Dentre as doenças cardíacas, a doença degenerativa crônica de mitral foi a mais prevalente, seguida da dirofilariose. Em relação as afecções respiratórias, a bronquite crônica e o colapso de traqueia foram mais diagnosticadas, seguidas da broncopneumonia e da síndrome braquicefálica. Quando da observação do ritmo cardíaco por meio do eletrocardiograma, a arritmia sinusal, ritmo sinusal e sinus arrest foram os principais achados. Quanto aos achados laboratoriais, foi possível observar aumento da média de hematimetria, redução da média do hematócrito e das plaquetas. Entretanto, alguns animais apresentaram azotemia, leucocitose e eosinofilia. Observou-se que pacientes com doenças cardíacas em estágios de congestão possuem redução da pressão arterial, aumento da hematimetria e taquiarritmias, como taquicardia sinusal e/ou complexos atriais prematuros. Pacientes com idade mais avançada tendem a ter redução dos valores de leucometria global e maior probabilidade de manifestação de aumento da pressão arterial. Portadores de dirofilariose cursam com aumento de eosinófilos.

Elderly dogs are frequently affected by diseases in the cardiovascular and respiratory system, being often asymptomatic until they are indicated for a surgical procedure that requires preoperative evaluation, at which point many clinical findings can be detected, to the point of need for treatment prior to surgical intervention. Therefore, the work aims to detect the main cardiorespiratory manifestations and their correlation to data found in complementary exams and demographic information of 138 animals treated at a service specialized in cardiology and respiratory diseases, from 2017 to 2021, for risk purposes surgical. It was possible to observe a greater predominance of elderly, small and female animals. Among heart diseases, chronic degenerative mitral disease was the most prevalent, followed by heartworm disease. Regarding respiratory affections, chronic bronchitis and tracheal collapse were more commonly diagnosed, followed by bronchopneumonia and brachycephalic syndrome. When observing the cardiac rhythm through the electrocardiogram, sinus arrhythmia, sinus rhythm and sinus arrest were the main findings. As for laboratory findings, it was possible to observe an increase in mean hematimetry, a reduction in mean hematocrit and platelets. However, some animals showed azotemia, leukocytosis and eosinophilia. It was observed that patients with cardiac diseases in stages of congestion have reduced blood pressure, increased hematimetry and tachyarrhythmias, such as sinus tachycardia and/or premature atrial complexes. Older patients tend to have reduced global white blood cell values and more likely to manifest increased blood pressure. Heartworm patients have an increase in eosinophils.

Eletrocardiografia computadorizada em cadelas com tumores mamários / Electrocardiography in bitches with mammary tumors

The incidence of cancer has increased due to greater longevity of the animals as a consequence of better control of other diseases, improvement of nutrition and good practices in preventive medicine. Malignant tumors can cause paraneoplastic syndrome such as hypercalcemia, anemia, cachexia, among others and consequent cardiovascular disorders. The electrocardiography (ECG) is a complementary exam that can reveal with its traces these rhythmic disorders. Based on that, the objective of this study was to evaluate the ECG in bitches with mammary tumors in order to detect in which type of tumor would be found significant changes as in cardiac rhythm, ECG waves, segments or cardiac axis. Twenty-nine female dogs were used in this study, being 19 bitches with mammary tumor, and they were allocated in three groups: G1: control group (n = 10), G2: benign neoplasia group (n = 6) and G3: malignant neoplasia group (n = 13). The most prevalent type of neoplasia in G2 was the benign mixed tumor (83%), followed by adenoma (17%) whereas in G3: carcinoma in mixed tumor (61%); papillary carcinoma (23%). Regarding cardiac rhythm, it was found sinus arrhythmia (SA) and normal sinus rhythm (NS): G1: 50% SA and 50% NS; G2: 67% SA and 33% NS; G3: 54% SA and 46% NS. No ventricular or atrial arrhythmias were detected. For other parameters in G1, G2 and G3, respectively (mean ± Std error): FC (bpm): 110±9.2, 120 ± 8.5, 124±7,5; P (ms): 48 ± 1.6, 51 ± 1.8, 50 ± 1.2; P (mV) 0.19 ± 0.02, 0.2 ± 0.02, 0.19 ± 0.02; PR (ms): 94 ± 4.3, 93 ± 5.5, 89 ± 3.9; QRS (ms): 56 ± 1.54, 60 ± 4, 62 ± 1.2; R (mV): 1.1 ± 0.06, 1.2 ± 0.24, 0.9 ± 0.13; QT (ms): 203 ± 9.4; 204 ± 7.9; 182 ± 15.6; and cardiac axis (°): 66 ± 6.2, 61 ± 7.9, 70 ± 7.5. There were no significant differences for all cardiac parameters and also for ST interval and T wave morphology. All electrocardiographic parameters found are in accordance with other studies carried out in the canine species. The results regarding tumor types differ from what was found in another study, in which in 18 bitches with mammary tumors, 55% were benign, with prevalence of adenomas (38%) followed by benign mixed tumors, and 45% malignant, with adenocarcinoma prevailing (22%). In another study, it was verified in 63 bitches the predominance of tubular carcinoma (26.56%) and carcinoma in mixed tumors (23.44%). Diverging from the electrocardiographic parameters of this study, a significant difference was found in the R wave amplitude value in the research by Barros et al., (2015) who performed computerized electrocardiography in 50 dogs, not only with mammary neoplasms (55% mammary carcinomas), but also in mastocytomas, lymphomas, benign tumors and other sarcomas. This author found out that the R wave amplitude values of the neoplasia group were lower when compared to the control group. In addition, we suspect that other types of tumors could result in more paraneoplastic syndrome than the mammary neoplasms found in this research. Neoplasms as lymphomas (T cells), apocrine gland anal sac adenocarcinomas, multiple myelomas and thymomas are known as a cause of hypercalcemia of malignancy and histiocytic sarcomas, myelomas, leukemia and lymphomas causing anemia. In conclusion, ECG has no changes in benign or malignant mammary tumors in dogs. However, this fact does not exclude the importance of its performance in pre-anesthetic evaluations. Further studies with a larger sample including the clinical staging of these bitches with a balanced number of animals with low and high staging are suggested.(AU)

Determination of the value of vertebral heart size regarding the weight and body area in canines / Determinação dos valores do vertebral heart size em relação ao peso e área corporal canina

The vertebral heart size is a method used to measure the cardiac dimension in order to identify the remodeling of the chambres in heart disease. This study aims to determinate the vertebral heart size values at right lateral and ventrodorsal radiographs views relating to canines weight and body area variations. For the purpose of the study 40 healthy dogs within the age of 1 to 6 years, males and females, with deep or intermediated thorax were selected, brachycephalic dogs were not included in the study; the dogs were separated in four groups: group 1(n=9) compound of dogs up to 5 kg; group 2 (n=8) with dogs from 5,1 to 10 kg; group 3 (n=12) with dogs from 10,1 to19 kg and group 4 (n=11) with dogs weighing more than 19,1 kg. The values of body score, body mass index and the thorax configuration where previously measured, as well as the vertebral heart size and the depth width ratio from the radiographs. The results demonstrated intervals of right lateral-lateral vertebral heart size 9.9 to 10.4v and ventro-dorsal vertebral heart size of 9.8-10.3v. The study results show that the vertebral heart size numbers did not correlate with weight or body area, regardless the type of radiography view. Therefore, it can be concluded that the vertebral heart size in right lateral and ventrodorsal radiography can be used to rate the cardiac area, not suffering influence by the dog's weight or body area.

O vertebral heart size é um método utilizado para mensurar a dimensão cardíaca visando identificar os remodelamentos das câmaras nas cardiopatias. O objetivo do estudo foi determinar os valores de vertebral heart size nas projeções radiográficas latero-lateral direita e ventro-dorsal conforme as variações do peso e área corporal. Para isso, foram selecionados 40 cães hígidos com idade entre 1 e 6 anos, machos e fêmeas, com padrão torácico intermediário e profundo, com exclusão dos braquicefálicos; os cães foram divididos em quatro grupos: grupo 1 (n=9) composto por cães de até 5 kg; grupo 2 (n=8) com cães de 5,1 a 10 kg; grupo 3 (n=12) com cães de 10,1 a 19 kg e grupo 4 (n=11) com cães acima de 19,1 kg. Os valores de escore corporal, índice de massa corporal e conformação torácica foram previamente mensurados, bem como os valores dos vertebral heart size a relação profundidade/largura torácica das radiografias. Os resultados demonstraram intervalos de vertebral heart size latero-lateral 9.9 a 10.4v e vertebral heart size ventro dorsal de 9.8-10.3v. Os valores não apresentaram correlação com o peso e área corporal nos grupos estudados, independente das projeções estudas. Assim, pode-se concluir que método vertebral heart size nas projeções estudadas é aplicável na avaliação da área cardíaca, não sofrendo influências do peso e área corporal canina.

Identificação e distribuição de lesões cardíacas em bovinos intoxicados por Amorimia exotropica / Identification and distribution of cardiac lesions in cattle poisoned by Amorimia exotropica

Amorimia exotropica é um arbusto escandente que pertence à família Malpighiacea, cujo princípio tóxico é o monofluoracetato de sódio e possui ação cardiotóxica em bovinos. Ela é a única representante, na região Sul do país, do grupo de plantas que causam morte súbita associada ao exercício. Este trabalho identificou e mapeou as lesões cardíacas observadas em bovinos intoxicados naturalmente por A. exotropica. Selecionaram-se nove corações bovinos, provenientes de um surto de intoxicação natural pela planta em uma propriedade de gado de corte do Rio Grande do Sul e procedeu-se o mapeamento de oito regiões topográficas distintas (ápice, ventrículos direito e esquerdo, septo interventricular, músculos papilares direito e esquerdo e átrios direito e esquerdo). À avaliação macroscópica quatro bovinos apresentaram lesão focal e bem delimitada no músculo papilar esquerdo. Estas áreas na histologia correspondiam à necrose de coagulação em diferentes estágios de evolução, similares a infartos. Todos os bovinos apresentavam necrose de cardiomiócitos, caracterizadas por retração e hipereosinofilia citoplasmática e fragmentação celular em todas as áreas amostradas. A severidade da injúria celular foi avaliada pela imuno-histoquímica anti-troponina C, a qual demonstrou acentuada perda e/ou diminuição de marcação citoplasmática em células necróticas. O músculo papilar esquerdo foi a região mais acometida nos casos de intoxicação por Amorimia exotropica...

Amorimia exotropica is a shrub of the Malpighiacea family that contains sodium monofluoroacetate as the toxic principle, which has a cardiotoxic action in cattle. In Southern Brazil it is the only species of the group of plants that causes "sudden death during exercise". This study has identified and mapped cardiac lesions observed in cattle naturally poisoned by A. exotropica. An outbreak of poisoning by the plant occurred in a beef cattle herd in Rio Grande do Sul, where nine bovine hearts were selected for examination and mapping of eight distinct topographical regions (apex, right and left ventricles, interventricular septum, right and left papillary muscles , right and left atrium). At gross examination, four cattle showed focal and well-defined lesions in the left papillary muscle. This corresponds to areas of coagulation necrosis in different stages of evolution on histology, similar to infarcts. All hearts showed cardiomyocytes necrosis, characterized by shrinkage and hypereosinophilic cytoplasm and cellular fragmentation in all sampled areas. The severity of cellular injury was evaluated by immunohistochemistry anti-troponin C, which showed marked decrease of cytoplasm staining in necrotic cells. The left papillary muscle was the most affected region in cases of poisoning by A. exotropica...

Electrocardiographic study in the American Quarter Horse breed / Estudo eletrocardiográfico de equinos da raça Quarto de Milha

An evaluation of the electrocardiographic profile of 50 clinically healthy Quarter Horses, with ages ranging from six months to 28 years old, 34 females and 16 males, was performed. Heart rate has not decreased with age, and duration of the QRS complex increased with the growth of the animal. The amplitude of the S and T1 waves were higher in male subjects than in female Quarter Horses.

Avaliou-se o perfil eletrocardiográfico de 50 equinos da raça Quarto de Milha, clinicamente sadios, com idades variando de seis meses a 28 anos, sendo 34 fêmeas e 16 machos. A frequência cardíaca não diminuiu com a idade, e a duração do complexo QRS aumentou ao longo do crescimento do animal. A amplitude das ondas S e T1 foram maiores nos indivíduos machos do que nas fêmeas da raça Quarto de Milha.