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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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]