Aberrant Right Subclavian Artery in a Dog - Clinical and Imaging Aspects

Background: Aberrant right subclavian artery is only rarely observed in veterinary medicine. Some animals may present postprandial regurgitation and progressive weight loss, which is considered an incidental finding unrelated to clinical alterations. Advanced imaging techniques such as thoracic CT scan, magnetic resonance imaging (MRI) and contrast angiography are used for the accurate detection of lesions, anatomical changes and specific information about vascular rings. This paper describes the clinical changes, imaging exams and therapeutic approach in a female dog with megaesophagus induced by an aberrant right subclavian artery.   Case: A 2-month-old female bull terrier, weighing 1.6 kg, with a history of regurgitation immediately or a few minutes after a meal, diarrhea, polyphagia, progressive emaciation and apathy for 45 days, was treated at a University Veterinary Hospital. The dog’s physical examination revealed 7% dehydration and body condition score 1 (scale 1 to 5), but no cardiac or pulmonary alterations upon auscultation. The hematological analysis and renal and hepatic serum enzymes were within the normal range for the species. In view of the presumptive clinical diagnosis of vascular anomaly, suggested by the contrast X-ray examination, a chest tomography was performed, which revealed altered aortic arch shape and contours, and a posterior aneurysm in the area of ​​abnormal connection of the right subclavian artery. The patient was released with a prescription for conservative dietary management for megaesophagus. Within two weeks, the patient returned with a report of a good response to the prescribed therapy, absence of vomiting and diarrhea, and an increase in body weight. Surgical correction was recommended, but has not been performed so far, but conservative treatment for megaesophagus was continued. No further episodes of regurgitation were identified during the nine-month follow-up period. Discussion: In the case reported here, the right subclavian artery is considered anatomically atypical because it arises directly from the aortic arch.  This vascular anomaly passes on to the right pectoral limb, dorsal to the esophagus, contracting it in its dorsal aspect. It tends to affect purebred dogs, occurring more frequently in Irish setters, German shepherds and Labrador retrievers, although it has been described in other breeds such as the bull terrier documented here and mixed breed dogs. Vascular ring anomalies may not cause clinical changes in animals and represent only incidental findings, or they may lead to gastrointestinal changes resulting from esophageal stricture, contributing to megaesophagus and clinical signs of esophageal obstruction, especially in recently weaned puppies. Such alterations were observed in this case, with the dog presenting regurgitation, immediately or a few minutes after a meal, megaesophagus, diarrhea and progressive weight loss. A CT scan was performed to confirm the type and location of the vascular anomaly and diagnostic accuracy, as recommended in the literature. Dietary therapy is one of the approaches adopted for patients presenting with regurgitation resulting from megaesophagus secondary to vascular anomalies. The dog in this report responded well to the medical therapy; nevertheless, the treatment of choice to correct the esophageal obstruction caused by this anomaly is surgical sectioning of the aberrant vessel by right intercostal thoracotomy, given that the degree of esophageal dilation and dysfunction tends to increase over time. However, at this time, the animal’s owner decided to suspend the recommended surgical procedure. Keywords: aberrant right subclavian artery, female dog, megaesophagus. Título: Artéria Subclávia Direita Aberrante em cão - aspectos clínicos e de imagem. Descritores: artéria subclávia direita aberrante, cão fêmea, megaesôfago

Pectus Excavatum and Pectus Carinatum in dogs

Background: Deformities of the anterior thoracic wall are called pectus: pectus excavatum and pectus carinatum. Pectus excavatum is characterised by dorsal deviation of the caudal region of the sternum while pectus carinatum consists of protrusion of the sternum and/or adjacent cartilage. Both defects may remain symptom-free, but respiratory and cardiac abnormalities have been reported. Another deformity observed in dogs is the swimming dog syndrome, which consists of the lateral opening of the thoracic and pelvic limbs, associated with the pedalling movement. These disorders are frequently reported in medical practice, are considered rare among canines. This report aims to describe a case of pectus excavatum associated with the swimming dog syndrome (Case 1) and another case of pectus carinatum (Case 2).Case: In Case 1, an approximately 45-day-old male American Pitbull canine had difficulty standing. Physical examination revealed hyperextension of the thoracic and pelvic limb joints and flattening of the thorax. After radiographic examination, pectus excavatum and the swimming dog syndrome were confirmed. The conservative treatment with splinting and hydrotherapy was chosen. At the 3-month follow-up, slight improvement in the limbs and irregular and unsatisfactory growth of the thorax leading to episodes of dyspnoea were observed. In Case 2, a female Pug, approximately 2 months old, had a thorax deformity. Physical examination revealed thorax protrusion, confirmed on radiography as pectus carinatum. Conservative therapy was provided using compressive bandage. One month later, the tutor reported improvement in the condition and absence of respiratory changes.Discussion: Pectus deformities has low incidence, and cases to pectus carinatum, there is a sexual predisposition, that is, males are more predisposed, differing from Case 2, a female dog. In the cases of pectus excavatum, no genetic alteration was directly related to its occurrence, although familial occurrence is reported in humans, as in Case 1, in which the patient was the only one of this litter to present this deformity. Though the possibility is lower, the acquired aetiology has been described in other cases. In pectus carinatum, there is the possibility of an acquired aetiology, which corroborates Case 2, considering that the canine had no history of inbreeding, nor family history. However, it is important consider racial predisposition, where there is an increasing number of cases of pectus carinatum in brachycephalic canines. Respiratory symptoms are frequently reported in cases of pectus excavatum, which the evolution of the condition occurred in Case 1, that can be explained by the displacement of organs or the restriction to ventilation. Humans have shown that pectus excavatum reduces static lung function. Case 2 showed no clinical signs, despite this presented dextrocardia, which in the future may confer cardiac dysfunctions. The diagnosis for pectus is considered simple. Performed only by radiography, it can be complemented by echocardiography. In both cases, conservative treatment was the choice. However, in Case 1 there was no success due to the degree of patient involvement, unlike Case 2, which had a better development of the thoracic wall, ensuring better quality of life for the patient. Thus, it is possible to conclude that some differences were found in these two reported cases when compared to others described in the literature.  The radiographic diagnosis is confirmatory, and the therapy must be adequate to the degree of thoracic wall deformity. In addition, the prognosis is more reserved for pectus excavatum than pectus carinatum

Aberrant Right Subclavian Artery in a Dog - Clinical and Imaging Aspects

Background: Aberrant right subclavian artery is only rarely observed in veterinary medicine. Some animals may present postprandial regurgitation and progressive weight loss, which is considered an incidental finding unrelated to clinical alterations. Advanced imaging techniques such as thoracic CT scan, magnetic resonance imaging (MRI) and contrast angiography are used for the accurate detection of lesions, anatomical changes and specific information about vascular rings. This paper describes the clinical changes, imaging exams and therapeutic approach in a female dog with megaesophagus induced by an aberrant right subclavian artery.   Case: A 2-month-old female bull terrier, weighing 1.6 kg, with a history of regurgitation immediately or a few minutes after a meal, diarrhea, polyphagia, progressive emaciation and apathy for 45 days, was treated at a University Veterinary Hospital. The dog’s physical examination revealed 7% dehydration and body condition score 1 (scale 1 to 5), but no cardiac or pulmonary alterations upon auscultation. The hematological analysis and renal and hepatic serum enzymes were within the normal range for the species. In view of the presumptive clinical diagnosis of vascular anomaly, suggested by the contrast X-ray examination, a chest tomography was performed, which revealed altered aortic arch shape and contours, and a posterior aneurysm in the area of ​​abnormal connection of the right subclavian artery. The patient was released with a prescription for conservative dietary management for megaesophagus. Within two weeks, the patient returned with a report of a good response to the prescribed therapy, absence of vomiting and diarrhea, and an increase in body weight. Surgical correction was recommended, but has not been performed so far, but conservative treatment for megaesophagus was continued. No further episodes of regurgitation were identified during the nine-month follow-up period. Discussion: In the case reported here, the right subclavian artery is considered anatomically atypical because it arises directly from the aortic arch.  This vascular anomaly passes on to the right pectoral limb, dorsal to the esophagus, contracting it in its dorsal aspect. It tends to affect purebred dogs, occurring more frequently in Irish setters, German shepherds and Labrador retrievers, although it has been described in other breeds such as the bull terrier documented here and mixed breed dogs. Vascular ring anomalies may not cause clinical changes in animals and represent only incidental findings, or they may lead to gastrointestinal changes resulting from esophageal stricture, contributing to megaesophagus and clinical signs of esophageal obstruction, especially in recently weaned puppies. Such alterations were observed in this case, with the dog presenting regurgitation, immediately or a few minutes after a meal, megaesophagus, diarrhea and progressive weight loss. A CT scan was performed to confirm the type and location of the vascular anomaly and diagnostic accuracy, as recommended in the literature. Dietary therapy is one of the approaches adopted for patients presenting with regurgitation resulting from megaesophagus secondary to vascular anomalies. The dog in this report responded well to the medical therapy; nevertheless, the treatment of choice to correct the esophageal obstruction caused by this anomaly is surgical sectioning of the aberrant vessel by right intercostal thoracotomy, given that the degree of esophageal dilation and dysfunction tends to increase over time. However, at this time, the animal’s owner decided to suspend the recommended surgical procedure. Keywords: aberrant right subclavian artery, female dog, megaesophagus. Título: Artéria Subclávia Direita Aberrante em cão - aspectos clínicos e de imagem. Descritores: artéria subclávia direita aberrante, cão fêmea, megaesôfago

Chondroprotectant therapy in rats with degenerative joint disease experimentally transected cranial cruciate

A osteoartrite (OA) é a doença articular mais comum em humanos e animais, o que ocasiona restrição de movimentos e dor, na região acometida. Tal enfermidade afeta mais de 25% dos humanos acima de 60 anos e, aos 70 anos, ela é considerada universal. Estima-se que nos Estados Unidos da América, 20% ou mais da população canina é acometida pela OA. O presente estudo tem como finalidade avaliar a terapia medicamentosa (polisulfato de pentosano, betametasona e sulfato de condroitina/glucosamina), em um modelo experimental de OA cirurgicamente induzido, em ratos. A doença articular foi promovida pela transecção cirúrgica do ligamento cruzado cranial, sendo que, após o procedimento cirúrgico, os animais foram mantidos e tratados por oito semanas. Foi realizada avaliação radiográfica e tomográfica antes e oito semanas após a indução da osteoartrite. Todos os animais foram submetidos à eutanásia para análise macroscópica e microscópica, que foram realizadas para avaliar a progressão da enfermidade e a ação terapêutica.  Na análise macroscópica foi observadas lesões nos joelhos submetidos à indução OA. Os animais não tratados apresentaram lesões graves enquanto que, os animais tratados apresentaram lesões leves a moderadas. Concluiu-se que o polissulfato de pentosano é eficiente no tratamento de lesões articulares iatrogênicas de ratos, uma vez que outros tratamentos não mostraram qualquer diferença significativa.Osteoarthritis (OA) is the most common joint disease in both humans and animals, and it results in movement restriction and pain at the affected area. This disorder affects more than 25% of people over 60 years of age, and it is considered universal for 70-year-old people. OA is estimated to affect over 20% of the canine population from the United States of America. The present study aimed to evaluate the treatment of rats that were surgically induced to OA using two different drug therapies, one with pentosan polysulfate, one with betamethasone, and one with chondroitin sulfate/ glucosamine. In order to produce joint disease, the cranial cruciate ligament was surgically transected. Animals were kept and treated for eight days after surgery and were assessed via both radiographies and tomographies taken before surgery and eight weeks later. All animals were euthanized having both macroscopic and microscopic analysis performed to evaluate the disorder progression and therapeutic action. Macroscopic analysis showed lesion in the knees subjected to OA induction. The untreated animals presented major lesions whereas the treated ones presented mild to moderate lesions. In conclusion, pentosan polysulfate is recommendable for the treatment of iatrogenic joint lesions in rats since the other treatments showed no significant difference

USO DE BIOMARCADORES CK-NAC, CK-MB E TROPONINA I EM CÃES COM DOENÇA CARDÍACA

O uso de biomarcadores cardíacos para diagnóstico clínico vem aumentando, porém, em medicina veterinária o uso ainda é restrito a pesquisas. Objetivou-se com esse trabalho avaliar a confiabilidade dos valores séricos de creatinoquinase, creatinoquinase fração MB e troponina I- fração cardíaca (Tnlc), na doença cardíaca correlacionando com a presença ou não de sinais clínicos. Foram avaliados 45 animais de diferentes raças, sexo e idade, separados em dois grupos. Ao grupo I foram selecionados 15 cães clinicamente sadios e sem alterações em radiografia, eletrocardiografia e ecocardiografia. No grupo II foram inseridos 30 cães com sinal clínico de doença cardíaca e com alteração em ao menos um dos exames utilizados na avaliação cardíaca. A idade variou de 1 a 11 anos de idade no grupo I (controle) e de 2 a 17 anos no grupo II. O sinal clínico mais relatado foi tosse, seguido por cansaço fácil. Os valores de referência para CK-MB no grupo I variou de 95 a 262 U/I com média de 157±49,99 e no grupo II (cardiopatas) variou de 74 a 787 U/L com média de 187,46±161,10, porém não houve diferença significativa (P≤0,05) entre os grupos para os valores de CK-MB e CK-NAC. O teste rápido de troponina I - fração cardíaca (Tnlc) apresentou resultado negativo para os 45 animais do estudo. Nesta pesquisa, o CK-MB não se mostrou um bom indicador de doença cardíaca, porém recomendam-se análises futuras com aumento no numero de cães

Myxomatous Degeneration of Atrioventricular Valves in a Crab-eating fox (Cerdocyon thous) - Echodopplercardiography Diagnosis

Background: The myxomatosis degeneration is a degenerative cardiac valve disease, with a higher incidence in male and senile canids. The diagnosis is made by a doppler echocardiography exam. Although there are few reports on the occurrence of cardiopathies in wild dogs (Cerdocyon thous), some studies on their cardiological parameters can be found. Considering this, and knowing that the cardiopathies in wild canids are common post mortem findings, the objective of this study is to describe the echocardiography diagnosis of a case of myxomatous degeneration of the atrioventricular valves in 1 wild dog (Cerdocyon thous) living in captivity.Case: It was treated at the Diagnostic Imaging Department of the Veterinary Hospital of the Federal University of Mato Grosso (HOVET-UFMT), 1 wild dog (C. thous), male, living in captivity with approximately 10-year-old, directed by the Center of Medicine and Research in Wild Animals of Cuiabá, to perform echocardiography exam. The patient was submitted to anesthesia for proper examination, which was used Esaote® machine model MyLabFive VET with sector scan transducer (4.0 -7.5 MHz). The longitudinal, transverse and apical scan planes were obtained through left and right parasternal windows. The evaluation of M mode exposed ejection fraction and shortening increased, of 81% and 47%, respectively, however it showed no increase in systolic and diastolic values of left ventricle, nor in right cavities on subjective evaluation. The relation between the left atrium (LA) and the aorta (Ao) remained normal, at 1.2 mm, with dimensions of 13.4 mm from the AO and 16.3 mm from LA, compatible with species parameters or domestic canines. The atrioventricular valves showed thickening and irregularities in their cusps, with great intensity in the left atrioventricular valve (LAV). The Doppler mode analysis revealed a turbulent systolic flow into the left atrium and right atrium, constituting transvalvular LAV and right atrioventricular valve- (RAV) regurgitation, both observed through the blood flow in colored Doppler and measured through the reflux velocity of 4.02 m/s of LAV and 2.17 m/s of RAV by the continuous Doppler, showing insufficiency of intense degree of LAV and moderate degree of RAV, no evidence of pulmonary hypertension. On the other hand, the relation between wave E and wave A (E/A) was 1.0, with increased transvalvular velocities and values of 0.95 m/s for wave E and A. The isovolumetric mitral relaxation time was approximately 76 m/s. The value of the pressure derivative (dp) in relation to time (dt) dp/dt measured from the LAV reflux was 1257 mmHg, within the limit considered normal for canines. Four months after the diagnosis, the patient died due to complications of chronic renal failure.Discussion: Despite being a commonly diagnosed pathology in domestic canids, the myxomatous degeneration of atrioventricular valves is still little reported in wild canids. The evaluation of the results showed that although there was severe LAV regurgitation, there was no hypertrophy or compensatory dilation of the left cavities. However, there was a compensatory increase in the shortening fraction together with the ventricular relaxation deficit. The diagnosis of this condition in Cerdocyon thous demonstrates that the pathology can affect animals of advanced age and that its incidence needs to be determined in these captive species, in order to understand the real impact of this disease in these populations. Keywords: cardiopathies, cardiac valve disease, degenerative disease, cardiological parameters, wild dog. Título: Degeneração mixomatosa das válvulas atrioventriculares em cachorro-do-mato (Cerdocyon thous) - diagnóstico ecocardiográfico Descritores: cardiopatias, doença valvular cardíaca, doença degenerativa, parâmetros cardiológicos, canídeo selvagem

Myxomatous Degeneration of Atrioventricular Valves in a Crab-eating fox (Cerdocyon thous) - Echodopplercardiography Diagnosis

Background: The myxomatosis degeneration is a degenerative cardiac valve disease, with a higher incidence in male and senile canids. The diagnosis is made by a doppler echocardiography exam. Although there are few reports on the occurrence of cardiopathies in wild dogs (Cerdocyon thous), some studies on their cardiological parameters can be found. Considering this, and knowing that the cardiopathies in wild canids are common post mortem findings, the objective of this study is to describe the echocardiography diagnosis of a case of myxomatous degeneration of the atrioventricular valves in 1 wild dog (Cerdocyon thous) living in captivity.Case: It was treated at the Diagnostic Imaging Department of the Veterinary Hospital of the Federal University of Mato Grosso (HOVET-UFMT), 1 wild dog (C. thous), male, living in captivity with approximately 10-year-old, directed by the Center of Medicine and Research in Wild Animals of Cuiabá, to perform echocardiography exam. The patient was submitted to anesthesia for proper examination, which was used Esaote® machine model MyLabFive VET with sector scan transducer (4.0 -7.5 MHz). The longitudinal, transverse and apical scan planes were obtained through left and right parasternal windows. The evaluation of M mode exposed ejection fraction and shortening increased, of 81% and 47%, respectively, however it showed no increase in systolic and diastolic values of left ventricle, nor in right cavities on subjective evaluation. The relation between the left atrium (LA) and the aorta (Ao) remained normal, at 1.2 mm, with dimensions of 13.4 mm from the AO and 16.3 mm from LA, compatible with species parameters or domestic canines. The atrioventricular valves showed thickening and irregularities in their cusps, with great intensity in the left atrioventricular valve (LAV). The Doppler mode analysis revealed a turbulent systolic flow into the left atrium and right atrium, constituting transvalvular LAV and right atrioventricular valve- (RAV) regurgitation, both observed through the blood flow in colored Doppler and measured through the reflux velocity of 4.02 m/s of LAV and 2.17 m/s of RAV by the continuous Doppler, showing insufficiency of intense degree of LAV and moderate degree of RAV, no evidence of pulmonary hypertension. On the other hand, the relation between wave E and wave A (E/A) was 1.0, with increased transvalvular velocities and values of 0.95 m/s for wave E and A. The isovolumetric mitral relaxation time was approximately 76 m/s. The value of the pressure derivative (dp) in relation to time (dt) dp/dt measured from the LAV reflux was 1257 mmHg, within the limit considered normal for canines. Four months after the diagnosis, the patient died due to complications of chronic renal failure.Discussion: Despite being a commonly diagnosed pathology in domestic canids, the myxomatous degeneration of atrioventricular valves is still little reported in wild canids. The evaluation of the results showed that although there was severe LAV regurgitation, there was no hypertrophy or compensatory dilation of the left cavities. However, there was a compensatory increase in the shortening fraction together with the ventricular relaxation deficit. The diagnosis of this condition in Cerdocyon thous demonstrates that the pathology can affect animals of advanced age and that its incidence needs to be determined in these captive species, in order to understand the real impact of this disease in these populations. Keywords: cardiopathies, cardiac valve disease, degenerative disease, cardiological parameters, wild dog. Título: Degeneração mixomatosa das válvulas atrioventriculares em cachorro-do-mato (Cerdocyon thous) - diagnóstico ecocardiográfico Descritores: cardiopatias, doença valvular cardíaca, doença degenerativa, parâmetros cardiológicos, canídeo selvagem

Incidental Adrenocortical Carcinoma in Dogs: Clinical, Tomographic and Histopathological

Background: Adrenal incidentalomas are masses accidentally discovered during imaging examinations performed when there is no suspicion of adrenal disease. Even with a low prevalence, it is important to perform a reliable evaluation observing biological behavior and determining whether the hormonal activity is stimulated. Frequently, these masses are not functional, but in some cases, there is increased cortisol activity, and patients with adrenal incidentalomas may present hyperadrenocorticism. This report aims to describe the clinical, tomographic, and histopathological aspects of a case of adrenal incidentaloma detected in a routine abdominal ultrasound.Case: An 8-year-old, male, maltese dog with occasional emesis, halitosis, claudication of the left pelvic limb, and previous compensated and untreated cardiomyopathy was treated at the Veterinary Hospital of the Federal University of Mato Grosso (HOVET-UFMT). Physical examination revealed arterial hypertension and claudication, with the positive posterior drawer test suggesting rupture of the cruciate ligament. The blood count showed no alteration, and the serum biochemistry revealed a slight increase in the activity of alanine aminotransferase. In order to investigate this increase, an abdominal ultrasound was performed. Slight hepatomegaly and a heterogeneous mass of irregular edges were observed with a moderate and difficult-to-delimit vascularization of the adrenal gland. Left knee radiography raised the suspicion of rupture of the cranial cruciate ligament due to the cranial displacement of the tibia in relation to the femur. Computed tomography was performed to define the extent and delimitation of the mass, which was compatible with a tumor of the right adrenal gland characterized by the visualization of an abdominal mass between the kidneys, extending from the hepatic region to the cranial pole of the left kidney. On follow-up, the patient was reported to have diarrhea with black stools, and a low-dose dexamethasone suppression test was ordered. Unilateral adrenalectomy was recommended due to the suspicion of pheochromocytoma. During the surgical procedure, the mass adhered to the abdominal wall and the diaphragm resulting in the death of the animal. Histopathological analysis revealed a cellular proliferation of cortical adrenal cells forming multiple cell nests separated by a small amount of fibrovascular stroma. Proliferated cells were polyhedral, with densely eosinophilic cytoplasm and well-defined edges, and were occasionally vesicular. They had globular nuclei, slightly stained chromatin, and inconspicuous nucleoli. Pleomorphism, anisocytosis, and anisokaryosis were accentuated, and eight mitosis figures were observed in ten high-power fields (40×), leading to a diagnosis of adrenocortical carcinoma.Discussion: When there is no suspicion or characteristic clinical sign, and adrenal growth is observed on imaging examination, the finding may be called an incidentaloma. Here, the incidentaloma was a non-functional adrenal carcinoma, because the tests were not conclusive. Adrenal carcinomas grow by infiltrating adjacent tissues, such as the caudal vena cava. In this case, it infiltrated the abdominal wall and diaphragm. Therefore, imaging, ultrasound, and tomography examinations were important for the characterization of the adrenal incidentaloma in this dog. This adrenal incidentaloma, which was a carcinoma with metastasis to the adjacent tissues, required other hormonal tests to rule out further endocrine dysfunctions.