Communication [Comunicação] Comparison between conventional and computerized electrocardiography in cats [Comparação entre registros eletrocardiográficos convencional e computadorizado em gatos]

RESUMOEstudaram-se os parâmetros eletrocardiográficos utilizando-se os métodos convencional, computadorizado e computadorizado impresso de 30 cães da raça Beagle clinicamente normais. As medidas eletrocardiográficas dos três diferentes traçados foram analisadas na derivação DII. A comparação entre os métodos revelou diferença nos valores da onda P, onda R, complexo QRS, intervalo QT e intervalo PR e na polaridade da onda T. Este fato deve ser levado em consideração, na dependência do método a ser utilizado. Palavras-chave: cão, eletrocardiograma ABSTRACTElectrocardiographic parameters were studied in thirty healthy adult Beagles, using conventional and computerized methods and reading the computerized registration printed on paper. The electrocardiographic measurements of the three different tracings were analyzed in lead II. The results obtained showed that there are differences among the three methods for P wave, R wave, QRS complex, QT interval, PR interval and polarity of the T wave. Special attention should be given to these differences, depending on the chosen method.

The aim of this study was to verify the applicability and accuracy of B-mode ultrasonography in detecting malignancy in dog cutaneous neoplasms. Forty-two neoplasms (12 benign and 30 malignant) of mesenchymal, round cells, epithelial and melanocytic origins from 24 dogs of different breeds and ages were included. The ultrasound evaluation was performed with a linear multi-frequency transducer (7.0 to 12MHz), with frequency dependent on the mass dimension. Ultrasonographic characteristics of echogenicity (hypo/hyperechogenic), echotexture (homogeneous/heterogeneous), regularity, invasiveness in adjacent tissues were classified. Dimensions were also measured to calculate the depth/width ratio. Neoplasms were classified as malignant or benign after cytological and/or histopathological analysis and the results were associated with ultrasound characteristics. There was a significant association (P<0.05) between malignancy and echogenicity, echotexture and invasiveness in adjacent tissues, so that 84.6% of hypoechogenic neoplasms, 76.9% of heterogeneous masses and 88.2% of invasive neoplasms were classified as malignant. However, for all these associations, moderate predictive values were obtained, which may be due to the small experimental number included in this study. Therefore, although it has been observed that hypoechogenic, heterogeneous and invasive neoplasms were more prone to malignancy, these findings should be used with caution until new studies are developed with a greater number and variety of cutaneous neoplasms in dogs.

RESUMENEl desarrollo de una cardiomiopatía dosis dependiente es la principal limitación para el uso de doxorrubicina en protocolos de quimioterapia tanto en seres humanos como en animales. En estos casos, la función global del miocardio puede ser cedida, teniendo como resultado signos atribuibles a la insuficiencia cardíaca congestiva. En este estudio, nosotros investigamos la capacidad del índice de desempeño miocárdico de Tei para identificar disfunción de miocardio en perros sanos tratados con doxorrubicina a una dosis cumulativa de 210 mg/m 2 en un periodo de 147 días, comparándolo con otros indicadores ecográficos estándar de función sistólica y diastólica. Nuestros resultados indicaron que el índice de Tei, el tiempo de relajación isovolumétrica, el período de pre-eyección, y la relación período de pre-eyección/tiempo de eyección ventricular izquierda pudieron identificar los efectos cardiotóxicos de doxorrubicina en la función cardíaca cuando sólo 60 mg/m 2 habían sido administrados, mientras los parámetros estándar sistólicos y diastólicos, incluso el diámetro sistólico del ventrículo izquierdo, la fracción de eyección y la fracción de acortamiento, necesitaron por lo menos 120 mg/mg 2 para empeorar. Se concluye que la terapia prolongada con antraciclinas perjudica las funciones sistólica y diastólica, que pueden ser documentadas antes adicionándose el índice de Tei a la evaluación ecográfica estándar en animales que reciben doxorrubicina.Palabras clave: cardiotoxicidad, antraciclinas, disfunción cardiaca, quimioterapia. SUMMARYThe development of a dose-dependent cardiomyopathy is the main limitation for the use of doxorubicin in chemotherapy protocols in both humans and animals. In this setting, the global myocardial function may be compromised resulting in signs of congestive heart failure. In this study, we investigated the ability of the Tei index of myocardial performance to identify myocardial dysfunction in healthy dogs receiving doxorubicin to a cumulative dose of 210 mg/m 2 over 147 days, comparing it with other standard echocardiographic indicators of systolic and diastolic function. Our results indicated that the Tei index, the isovolumic relaxation time, pre-ejection period and the pre-ejection period-to-left ventricular ejection time ratio were able to identify the cardiotoxic effects of doxorubicin on cardiac function when only 60 mg/m 2 had been administered, while the standard systolic and diastolic parameters, including left ventricular diameter at systole, ejection fraction, and fractional shortening needed at least 120 mg/mg 2 to deteriorate. We concluded that prolonged anthracycline therapy compromises both systolic and diastolic functions, which may be documented earlier by including the Tei index evaluation to the standard echocardiographic assessment of animals receiving doxorubicin.

Visceral leishmaniasis (VL) is a cosmopolitan parasitic zoonosis that can promote myocarditis and heart rate changes in canine and human hosts. Thus, histopathological aspects of the myocardium and clinical, hematological, biochemical, radiological and electrocardiographic data were evaluated in a group of 36 dogs naturally infected with VL (VLG) and compared to data from 15 non-infected dogs (CG=Control Group). A prevalence of asymptomatic dogs was present in the CG (100%) and polysymptomatic dogs in the VLG (66%). In addition, two dogs in the VLG demonstrated systolic murmurs in the mitral valve region: one with a II/VI intensity and the other with a III/VI intensity. The mean values of RBC, hemoglobin and hematocrit were lower in dogs in VLG and were associated with higher values of total protein, total leukocytes, neutrophils, creatine kinase overall (CK) and the CK-MB fraction (CK-MB). The absence of radiographic changes was accompanied by a predominance of respiratory sinus arrhythmia associated with episodes of migratory pacemaker and sinus arrest in dogs in VLG (75%), sinus rhythm in dogs in CG (60%) and decreased P wave amplitude in VLG electrocardiography. Mononuclear cell infiltration was detected in the myocardium of 77,8% of dogs in GVL and classified primarily as mild multifocal lymphohistioplasmacytic. Amastigotes were detected in only one dog, which did not allow the association between myocarditis and parasitism, although the myocardial lesions that were found constitute irrefutable evidence of myocarditis in the VLG dogs, accompanied by lenient electrocardiographic changes compared to CG. Keywords: Electrocardiography, Leishmania sp., visceral leishmaniasis, dogs RESUMO A leishmaniose visceral (LV) é uma zoonose parasitária cosmopolita capaz de promover miocardite e alterações no ritmo cardíaco em cães e seres humanos. Dessa forma, os aspectos clínicos, hematimétricos, bioquímicos, radiográficos, eletrocardiográficos e histopatológicos do miocárdio foram avaliados em 36 cães naturalmente infectados com LV (GLV) e comparados a 15 cães não infectados (GC). Houve predomínio de cães assintomáticos no GC (100%) e polissintomáticos no GLV (66%). Dois cães do GLV apresentaram sopro sistólico de intensidade II/VI e III/VI, em região de foco mitral. Os valores médios de hemácia, hemoglobina e hematócrito foram inferiores nos cães do GLV, associados a maiores valores de proteína total, leucócitos totais, neutrófilos, creatinina quinase total (CK) e fração MB (CK-MB

A 10-month-old intact female mixed breed dog was referred for evaluation of exercise-induced dyspnea and a low grade II/VI systolic murmur was detected. The communication between ascending aortic and pulmonary trunk was observed by detecting a continuous flow just above the semilunar valves on echoDopplercardiography and attested by surgery. After the surgical procedure, the dog was presented in good clinical conditions without exercise-induced dyspnea, reflecting the importance of an early and accurate diagnostic for the therapeutic success. This is the first Brazilian report of this rare congenital disease and the unique well succeed surgery in the veterinary literature.Keywords: dog, aorticopulmonary window, aorticopulmonary fenestration RESUMO Na avaliação da dispneia pós-exercício em uma cadela de 10 meses de idade, não castrada e sem raça definida, foi detectado sopro sistólico leve grau II/VI. A comunicação entre a aorta ascendente e o tronco pulmonar, observada pela presença de fluxo contínuo logo abaixo das valvas semilunares

The present study has the objective of evaluating the effects of exercise training, using moderate intensity walking (60 to 80% of maximum heart rate), from 30 to 50 minutes, three times a week, in alternate days, during eight weeks, on heart rate variability in dogs with myxomatous valve disease (MVD). For that, 20 dogs in stages B1 (1), B2 (14) and C2 (5) of MVD (ACVIM classification) were divided into untrained control group (CG, n=9) and training group (TG, n=11), and assessed at baseline (T0), after four (T1) and eight weeks (T2). Only one B1 and five B2 dogs completed the training program. In the time domain, the rMSSD was greater in TG in T1 (155,5+42,07) and T2 (199,8+83,54) than CG (T1:91,17+35,79 and T2:88,17+57,51). In the frequency domain, the variable High Frequency (HF) increased in TG in T1 (30950+25810) and T2 (40300+33870) when compared to the CG (T1:19090+23210 and T2:18810+22200) and within the group TG in T2 in relation to T0 (29340+20950). The proposed walking protocol is concluded to have increased the rMSSD and HF variables in TG, representing an increase of the parasympathetic tonus, justifying the indication of this therapy in B1 and B2 stages of MVD.

ABSTRACT. The Tei index of myocardial performance is a noninvasive echocardiographic parameter that combines systolic and diastolic time intervals to assess global cardiac performance. It was demonstrated to be a reliable indicator of myocardial dysfunction in dogs with varying clinical conditions. Because only a few studies focused on the measurement of the index in healthy dogs, this cross-sectional study was conceived to investigate how it performs in a large population of clinically healthy Beagle dogs. Our results showed no correlation between the index and body weight, heart rate, and several standard echocardiographic measures which are estimates of preload and afterload. There was no difference between de index calculated for males or females. Also, results indicated strong intra-observer and inter-observer correlations. In conclusion, the Tei index was shown to perform independently of loading conditions, besides being a straightforward and easily reproducible parameter.Key words: echocardiography, cardiac function, Doppler, dog. RESUMEN.El índice de rendimiento miocárdico es un parámetro ecocardiográfico no invasivo que combina intérvalos de tiempo sistólico y diastólico para evaluar el rendimiento cardiaco total. Se ha demostrado que es un indicador fiable de disfunción miocárdica en perros con diferentes condiciones clínicas. Debido a que pocos estudios se centraron en la medición de este índice en perros sanos, este estudio transversal fue concebido para investigar este rendimiento en una gran población de perros Beagle clínicamente sanos. Nuestros resultados no muestran correlación entre el índice y el peso corporal, la frecuencia cardiaca, y varias medidas ecocardiográficas que son estimaciones estándar de precarga y poscarga. No hubo diferencia entre machos y hembras para el índice calculado. Además, los resultados indicaron notorias correlaciones intraobservador e interobservador. En conclusión, el índice de Tei se mostró como un parámetro independiente de las condiciones de la carga, que además de ser fácil de calcular también es un parámetro de fácil reproducción.