Elaine Cristina Soares

Chronic valvular disease: correlation between clinical, electrocardiographic, radiographic and echocardiographic aspects in dogs

ABSTRACT Echocardiographic aspects of chronic mitral valvular disease were studied and compared to physical, radiographic and electrocardiographic aspects. Seventy dogs were used, and clinical examination, thoracic radiography, electrocardiogram and echocardiogram were performed. Correlations between regurgitation severity with cardiac failure functional class and murmur intensity were observed. The electrocardiogram showed a low sensibility in detecting cardiac chamber enlargement, caused by mitral regurgitation. All the dogs with severe mitral regurgitation showed cardiomegaly according to thoracic radiographies. Keywords: dog, heart, cardiac failure, echocardiography, cardiac valve RESUMO Avaliaram-se os aspectos ecocardiograficos da doenca valvar cronica, comparando-os com os aspectos clinicos, radiograficos e eletrocardiograficos em caes. Estudaram-se 70 animais, realizando-se exames fisicos, radiografias toracicas, eletrocardiograma e ecocardiograma. Observaram-se correlacoes entre a gravidade da regurgitacao, a classe funcional da insuficiencia cardiaca e a intensidade de sopro. O eletrocardiograma mostrou baixa sensibilidade para detectar aumento de câmaras cardiacas causadas por regurgitacao mitral. Todos os caes com regurgitacao mitral grave apresentaram cardiomegalia nas radiografias toracicas Palavras-chave: cao, coracao, insuficiencia cardiaca, ecocardiografia, valva cardiaca

Electrocardiographic Parameters of Captive Lions (Panthera leo) and Tigers (Panthera tigris) Immobilized with Ketamine Plus Xylazine

Abstract Twenty-seven healthy captive lions (Panthera leo) and 13 healthy captive tigers (Panthera tigris) from São Paulo Zoo (Fundação Parque Zoológico de São Paulo, São Paulo, Brazil) collection were selected for this study. They were anesthetized with ketamine (10 mg/kg) combined with xylazine (1–2 mg/kg) for physical examinations, hematologic and serum chemical analysis and electrocardiogram recording. The main aim of this research was to gather initial information about normal electrocardiographic parameters of large felids. Standard P-QRS-T deflections on leads described for domestic carnivores were analyzed, and they did not greatly differ from those of large felids, taking into account the greater weight and corporal mass of large felids. Heart rate of lions ranged from 42 to 76 beats per minute (bpm). Heart rate of tigers ranged from 56 to 97 bpm. In both species, the most common rhythm detected was normal sinus rhythm followed by sinus arrhythmia; wandering pacemaker was also observed with normal sinus rhythm or sinus arrhythmia. Mean electrical axis lay between +60° and +120°. QRS complexes were predominantly positive in leads DI, DII, DIII, and AVF, and negative in AVR and AVL. This study provides insights into normal electrocardiograms of large felids. Wider investigations on the same subject are necessary to establish criteria for the recognition of abnormalities in these species and should include other anesthetic drug(s) combinations and reports of electrocardiographic features of animals with cardiac disease and electrolytes disturbances.

Avaliação de alguns parâmetros ecocardiográficos do gato-do-mato (Leopardus tigrinus), mantido em cativeiro e submetido à anestesia com xilazina e quetamina

Some echocardiographic parameters in B, M-mode and Doppler of 27 Oncillas, Leopardus tigrinus, a wild little feline, kept in captivity and submitted to anesthesia with 1 to 2mg/kg of xilazine and 10mg/kg of ketamine, had been evaluated. Changes of the cardiovascular parameters were observed when the results were compared to non anesthetized domestic cat (Felis catus).

Aspectos radiográficos da doença valvar crônica

The radiographic examination is one of the most applied diagnostic method in chronic valvular disease, evaluating the cardiac silhouette and/or lung abnormalities. The radiographic cardiac image can be measured by the “vertebral heart size” system, proposed by BUCHANAN and BUCHELER (1995). Seventy dogs who presented murmur on auscultation, symptomatic or not, were studied, and the radiographic examination of them were evaluated by the “VHS” method. Clinical and radiographic findings were compared, indicating that the worse the severity of symptoms the higher the probability of finding cardiomegaly in radiographies. Besides, the higher the murmur intensity the more often the radiographic signs of cardiomegaly were observed.

Padronização de parâmetros ecocardiográficos de cães da raça Golden Retriever clinicamente sadios

The Duchennes muscular dystrophy (DMD) in humans is a recessive X-linked neuromuscular disease, caused either by the absence or dysfunction of the dystrophin. Clinically it is characterized by severe alteration in the skeletal musculature, resulting in precocious death of the affected patient. In Golden Retriever dogs, the mutation that determines the muscular dystrophy occurs spontaneously and the extensive homology among the pathogenesis of DMD and of Golden Retriever muscular dystrophy allows to qualify the dog as the main substitute of humans in the clinical tests of new therapies. The deficient myocardium in dystrophin is more vulnerable to the pressure overload, and the patients with DMD can develop dilated cardiomyopathy as well as arterial hypertension; in echocardiography, diastolic function abnormalities are verified and systolic inadequacy can be observed in some old patients. In the present study, 41 healthy Golden Retriever dogs were evaluated by echocardiographic exam with the purpose to obtain parameters for the standardization of these cardiovascular characteristics in the refered breed, what hereafter can be used as reference in the identification of bearer or affected dogs by muscular dystrophy.

Monitorização eletrocardiográfica ambulatorial por 24-horas em cães com cardiomiopatia dilatada idiopática

This study aimed to characterize 24-hour ambulatory electrocardiographic monitoring (Holter monitoring) in dogs with idiopathic dilated cardiomyopathy. Physical examination and indirect (Doppler) blood pressure measurement, and also electrocardiography, thoracic radiography, echocardiography, and 24-hour ambulatory electrocardiographic exams were performed in 40 dogs with idiopathic dilated cardiomyopathy. Ventricular extrasystoles were detected in 97.5% of the animals, and ventricular tachycardia in 45%. No correlation between the number of ventricular extrasystoles and the shortening fraction was observed. Concerning the clinical symptoms, there was only association between the presence of ventricular tachycardia and past report of syncope. It was concluded that the incidence of ventricular arrhythmias is high in dogs with dilated cardiomyopathy, being ventricular tachycardia, mostly non-sustained, relatively frequent.

Survival and echocardiographic evaluation of dogs with idiopathic dilated cardiomyopathy treated with carvedilol

Sixty dogs with idiopathic dilated cardiomyopathy were randomly treated with traditional therapy - digitalis, diuretics, angiotensin-converting inhibitors - (group A) or treated with these drugs plus carvedilol (group B). Echocardiographic variables were measured before and after 3, 13, 26, and 52 weeks of treatment or until death. Comparisons between groups and time were performed. No significant differences between groups were found in the most of the echocardiographic variables. The left ventricular end-systolic diameter indexed to body surface area (LVESDi) increased significantly in the group A dogs compared to the group B animals. The survival of groups A and B dogs were not different (P-value=0.1137). In conclusion, the stability of the LVESDi observed in the group treated with carvedilol may represent the beneficial effect over the ventricular remodeling.

Indices ecodopplercardiográficos de função diastólica de gatos saudáveis não sedados

The purpose of this study was to determine values as E and A waves velocities, E/A ratio, E wave deceleration time, and IVRT in healthy non-sedated cats, as well as correlate these indices to the heart rate. Forty healthy, adult cats housed in the cattery of the School of Veterinary Medicine of Sao Paulo University were studied. Mean, standard deviation, median, interquartilic interval and range were calculated. Doppler examination was performed with the cats restrained in left lateral recumbency. Good correlation between heart rate and E wave velocity, E/A ratio and IVRT was observed, whereas E wave deceleration time and A wave velocity were not affected by the heart rate. The estabilishment of these values will allow to define the pattern of the diastolic abnormality, usually related to cardiomyopathies in cats.