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Background: Canine hypercortisolism (HC) is the most prevalent endocrinopathy in dogs in southern Brazil. The prognosis depends on several factors including the general health status, owners´ commitment, and the development of disease complications and comorbidities occurrence, such as cardiovascular complications including mitral valve disease (MVD), systemic arterial hypertension, and left ventricular hypertrophy. The main objective of the present study was to assess cardiovascular parameters in canine HC, based on investigating survival-related variables. The study also aimed to evaluate the influence of concurrent preclinical (MVD) on dogs` survival and the impact of HC on MVD progression. Materials, Methods & Results: A total of 25 dogs with spontaneous HC were enrolled and divided into 2 subgroups accordingly to their echocardiographic findings: group HC (normal echocardiography at first evaluation, n = 16); and group HC + MVD (concurrent presence of stages B1 and B2 MVD diagnosed at the first evaluation, n = 9). The patients were evaluated at diagnosis (T0); 6 months after treatment begging (T1); and after 12 months of treatment (T2). The owners were further contacted by phone or e-mail for 1 more year after T2 regarding survival information. A control group (CG, n = 20) was also evaluated at T0 and T1. At each evaluation, dogs were submitted to a complete clinical evaluation and physical exam, associated with a minimum database (CBC, serum biochemistry, and urine analysis) and cardiovascular evaluation composed of systolic blood pressure determination, electrocardiogram (ECG), and echodopplercardiography. In the HC group, 11/16 dogs underwent the evaluation at T2, while 4/9 dogs from the HC + MVD group and 17/20 dogs from the CG underwent the evaluation at T2. Five dogs (31.25%) from the HC group and 4 dogs (44.44%) from the HC + MVD group died before the end of the follow-up period. In the control group, only 1 dog (5.26%) died before the end of the study. Despite the higher mortality in the HC + MVD group during the follow-up period, there was no significant difference (P = 0.632) in survival when compared with the HC group. The MVD of 4 dogs included in the HC + MVD group was classified as stage B1, while the other 5 dogs were classified as stage B2. Only 1 dog from the CG developed stage B1 MVD in the period studied; however, progression of the MVD stage was documented in 1/4 of dogs in the HC + MVD group and MVD development was documented in 3/11 of dogs from the HC group from T0 to T2. The odds ratio (OR) and respective 95% confidence interval (95%CI) for HC as a risk factor for MVD progression were 4.267 (0.4268 - 42.65; P = 0.342). Exercise intolerance (12/16 dogs) and dyspnea (6/16 dogs) were the cardiorespiratory clinical signs with the highest incidence in the HC group at T0. When compared to the control group, both exercise intolerance (P < 0.001) and dyspnea (P = 0.03) occurrence were significantly higher in the HC group. The age (P = 0.001) and the occurrence of dyspnea (P = 0.036) at diagnosis were significantly higher in dogs with HC that died during the follow-up than those that remained alive. Regarding the occurrence of cardiac arrhythmias verified by ECG, no statistically significant differences were observed among groups. Discussion: The study suggests that systemic hypertension and altered echocardiographic measurements did not interfere with dogs' survival; however, dyspnea was associated with a worse prognosis. Finally, it is possible to conclude that mitral valve degeneration is a common comorbidity in dogs with HC, however, it was not evidenced their interference in the survival of dogs with this endocrine disease or even a role of the HC in the progression of the MVD.

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A brown howler monkey (Alouatta guariba clamitans) was presented with lethargy, hyporexia, cough and heart murmur. The complementary tests and necropsy revealed pleuropneumonia, bacterial endocarditis and interventricular septal defect. To the best of our knowledge, this is the first report of increased cardiac troponin I levels in this species.

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Supraventricular trigeminy is an uncommon cardiac impulse formation disturbance. Detecting and treating cardiac arrhythmias is an important therapeutic goal in cardiology. The aim of this note is to report an occurrence of supraventricular trigeminy in a dog with myxomatous mitral valve disease (MMVD). A 15-year-old intact male mongrel dog weighing 13kg and with a history of heart murmur, cough, dyspnea, and ascites was referred for cardiac evaluation. Echocardiographic findings were consistent with a diagnosis of myxomatous mitral and tricuspid valves disease with a severe hemodynamic compromise. Electrocardiography (ECG) revealed a sinus arrhythmia with isolated supraventricular premature complexes, supraventricular couplets, and periods of supraventricular trigeminy. Previous retrospective and prospective studies that evaluated cardiac arrhythmias in dogs have not reported supraventricular trigeminy. The present report showed that supraventricular trigeminy may occur in dogs with MMVD with severe hemodynamic compromise, probably related to atrial enlargement. In addition, this case reinforces the importance of performing ECG in dogs with MMVD, since it complements the echocardiogram and enables a better therapeutic approach.(AU)

O trigeminismo supraventricular é um distúrbio incomum de formação do impulso elétrico cardíaco. Detectar e tratar arritmias cardíacas são um importante objetivo terapêutico em cardiologia. O objetivo desta nota é relatar a ocorrência de trigeminismo supraventricular em um cão com doença mixomatosa da valva mitral (DMVM). Um cão sem raça definida, macho, inteiro, 15 anos de idade e 13kg foi levado para avaliação cardíaca com um histórico de sopro cardíaco, tosse, dispneia e ascite. Os achados ecocardiográficos foram compatíveis com doença mixomatosa de valvas mitral e tricúspide com comprometimento hemodinâmico severo. A eletrocardiografia (ECG) revelou arritmia sinusal com presença de complexos supraventriculares prematuros isolados, aos pares e períodos de trigeminismo supraventricular. O trigeminismo supraventricular não é relatado em estudos retrospectivos e prospectivos que avaliaram arritmias cardíacas em um grande número de cães. O presente relato evidencia que o trigeminismo supraventricular pode ocorrer em cães com DMVM e comprometimento hemodinâmico severo, provavelmente relacionado à dilatação atrial. Ainda, reforça a importância da realização do ECG em cães com DMVM, complementando as informações ecocardiográficas e possibilitando uma melhor abordagem terapêutica.(AU)

Assuntos

RESUMO

Supraventricular trigeminy is an uncommon cardiac impulse formation disturbance. Detecting and treating cardiac arrhythmias is an important therapeutic goal in cardiology. The aim of this note is to report an occurrence of supraventricular trigeminy in a dog with myxomatous mitral valve disease (MMVD). A 15-year-old intact male mongrel dog weighing 13kg and with a history of heart murmur, cough, dyspnea, and ascites was referred for cardiac evaluation. Echocardiographic findings were consistent with a diagnosis of myxomatous mitral and tricuspid valves disease with a severe hemodynamic compromise. Electrocardiography (ECG) revealed a sinus arrhythmia with isolated supraventricular premature complexes, supraventricular couplets, and periods of supraventricular trigeminy. Previous retrospective and prospective studies that evaluated cardiac arrhythmias in dogs have not reported supraventricular trigeminy. The present report showed that supraventricular trigeminy may occur in dogs with MMVD with severe hemodynamic compromise, probably related to atrial enlargement. In addition, this case reinforces the importance of performing ECG in dogs with MMVD, since it complements the echocardiogram and enables a better therapeutic approach.

O trigeminismo supraventricular é um distúrbio incomum de formação do impulso elétrico cardíaco. Detectar e tratar arritmias cardíacas são um importante objetivo terapêutico em cardiologia. O objetivo desta nota é relatar a ocorrência de trigeminismo supraventricular em um cão com doença mixomatosa da valva mitral (DMVM). Um cão sem raça definida, macho, inteiro, 15 anos de idade e 13kg foi levado para avaliação cardíaca com um histórico de sopro cardíaco, tosse, dispneia e ascite. Os achados ecocardiográficos foram compatíveis com doença mixomatosa de valvas mitral e tricúspide com comprometimento hemodinâmico severo. A eletrocardiografia (ECG) revelou arritmia sinusal com presença de complexos supraventriculares prematuros isolados, aos pares e períodos de trigeminismo supraventricular. O trigeminismo supraventricular não é relatado em estudos retrospectivos e prospectivos que avaliaram arritmias cardíacas em um grande número de cães. O presente relato evidencia que o trigeminismo supraventricular pode ocorrer em cães com DMVM e comprometimento hemodinâmico severo, provavelmente relacionado à dilatação atrial. Ainda, reforça a importância da realização do ECG em cães com DMVM, complementando as informações ecocardiográficas e possibilitando uma melhor abordagem terapêutica.

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RESUMO: O trigeminismo supraventricular é um distúrbio incomum de formação do impulso elétrico cardíaco. Detectar e tratar arritmias cardíacas são um importante objetivo terapêutico em cardiologia. O objetivo desta nota é relatar a ocorrência de trigeminismo supraventricular em um cão com doença mixomatosa da valva mitral (DMVM). Um cão sem raça definida, macho, inteiro, 15 anos de idade e 13kg foi levado para avaliação cardíaca com um histórico de sopro cardíaco, tosse, dispneia e ascite. Os achados ecocardiográficos foram compatíveis com doença mixomatosa de valvas mitral e tricúspide com comprometimento hemodinâmico severo. A eletrocardiografia (ECG) revelou arritmia sinusal com presença de complexos supraventriculares prematuros isolados, aos pares e períodos de trigeminismo supraventricular. O trigeminismo supraventricular não é relatado em estudos retrospectivos e prospectivos que avaliaram arritmias cardíacas em um grande número de cães. O presente relato evidencia que o trigeminismo supraventricular pode ocorrer em cães com DMVM e comprometimento hemodinâmico severo, provavelmente relacionado à dilatação atrial. Ainda, reforça a importância da realização do ECG em cães com DMVM, complementando as informações ecocardiográficas e possibilitando uma melhor abordagem terapêutica.

ABSTRACT: Supraventricular trigeminy is an uncommon cardiac impulse formation disturbance. Detecting and treating cardiac arrhythmias is an important therapeutic goal in cardiology. The aim of this note is to report an occurrence of supraventricular trigeminy in a dog with myxomatous mitral valve disease (MMVD). A 15-year-old intact male mongrel dog weighing 13kg and with a history of heart murmur, cough, dyspnea, and ascites was referred for cardiac evaluation. Echocardiographic findings were consistent with a diagnosis of myxomatous mitral and tricuspid valves disease with a severe hemodynamic compromise. Electrocardiography (ECG) revealed a sinus arrhythmia with isolated supraventricular premature complexes, supraventricular couplets, and periods of supraventricular trigeminy. Previous retrospective and prospective studies that evaluated cardiac arrhythmias in dogs have not reported supraventricular trigeminy. The present report showed that supraventricular trigeminy may occur in dogs with MMVD with severe hemodynamic compromise, probably related to atrial enlargement. In addition, this case reinforces the importance of performing ECG in dogs with MMVD, since it complements the echocardiogram and enables a better therapeutic approach.

RESUMO

This study describes a case of tetralogy of Fallot in a lamb showing failure to thrive and signs of respiratory distress. Physical examination, electrocardiography, thoracic radiographies, echocardiography and cardiac troponin I evaluation were performed. The value of cardiac troponin I was compared with the values of 10 healthy lambs of the same age and breed, and the affected animal demonstrated an increase in cardiac troponin I. Due to the poor prognosis, euthanasia was indicated, and necropsy confirmed the diagnosis. This is the first report of an increase in cardiac troponin I in a lamb with tetralogy of Fallot.

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A hipertensão arterial sistêmica (HAS) é uma doença que acomete cães e gatos, e manifesta-se, namaioria das vezes, secundariamente à outra afecção. Elevações constantes da pressão sanguínea podem,com o tempo, causar sérias consequências clínicas. É importante o conhecimento da fisiologiacardiovascular e mecanismos compensatórios, com o objetivo de fazer uma abordagem terapêuticacorreta. Diversos fatores podem influenciar a aferição da pressão arterial de cães e gatos, como, porexemplo, o ambiente, o horário e o método utilizado. Assim, é importante que o exame seja padronizadoe o clínico tenha conhecimento destes fatores. A terapia dietética pode contribuir para o controleda doença, porém não existe comprovação de que ela seja eficaz isoladamente. Os inibidores da ECAe bloqueadores dos canais de cálcio são os medicamentos mais utilizados para o tratamento de HASem cães e gatos, respectivamente, porém outros fármacos devem ser considerados e novos fármacosestudados. O objetivo deste trabalho foi fazer uma revisão bibliográfica sobre o tratamento da hipertensãoarterial sistêmica em cães e gatos.(AU)

Systemic hypertension is a disease that affects dogs and cats, and manifests itself in most cases, secondaryto another condition. Constant elevations of blood pressure can, over time, lead to seriousclinical consequences. Cardiovascular physiology and compensatory mechanisms are important toa correct therapeutic approach. Blood pressure measurement may be influenced by several factors,such the environment, time and method. It is therefore important that these factors be known andthe measurement method standardized. The dietary therapy can help control the disease, but thereis no proof that is effective alone. ACE inhibitors and calcium channel blockers are the most widelydrugs used for the treatment of systemic hypertension in dogs and cats, however other drugs shouldbe considered and new drugs studied. The aim of this work was make an update on the treatment ofsystemic hypertension in dogs and cats.(AU)

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RESUMO

A hipertensão arterial sistêmica (HAS) é uma doença que acomete cães e gatos, e manifesta-se, namaioria das vezes, secundariamente à outra afecção. Elevações constantes da pressão sanguínea podem,com o tempo, causar sérias consequências clínicas. É importante o conhecimento da fisiologiacardiovascular e mecanismos compensatórios, com o objetivo de fazer uma abordagem terapêuticacorreta. Diversos fatores podem influenciar a aferição da pressão arterial de cães e gatos, como, porexemplo, o ambiente, o horário e o método utilizado. Assim, é importante que o exame seja padronizadoe o clínico tenha conhecimento destes fatores. A terapia dietética pode contribuir para o controleda doença, porém não existe comprovação de que ela seja eficaz isoladamente. Os inibidores da ECAe bloqueadores dos canais de cálcio são os medicamentos mais utilizados para o tratamento de HASem cães e gatos, respectivamente, porém outros fármacos devem ser considerados e novos fármacosestudados. O objetivo deste trabalho foi fazer uma revisão bibliográfica sobre o tratamento da hipertensãoarterial sistêmica em cães e gatos.

Systemic hypertension is a disease that affects dogs and cats, and manifests itself in most cases, secondaryto another condition. Constant elevations of blood pressure can, over time, lead to seriousclinical consequences. Cardiovascular physiology and compensatory mechanisms are important toa correct therapeutic approach. Blood pressure measurement may be influenced by several factors,such the environment, time and method. It is therefore important that these factors be known andthe measurement method standardized. The dietary therapy can help control the disease, but thereis no proof that is effective alone. ACE inhibitors and calcium channel blockers are the most widelydrugs used for the treatment of systemic hypertension in dogs and cats, however other drugs shouldbe considered and new drugs studied. The aim of this work was make an update on the treatment ofsystemic hypertension in dogs and cats.

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RESUMO

Background: Gastric-dilation volvulus complex (GDV) is an acute condition characterized by dilation of the stomach associated with rotation around its mesenteric axis. Cardiac arrhythmias, especially of ventricular origin are frequently found in animals with GDV. Ventricular tachycardia is characterized by three or more ventricular premature complexes in sequence. Atrial flutter is a supraventricular arrhythmia uncommon in dogs, characterized by rapid atrial rate and altered atrial depolarization resulting in bidirectional saw-toothed atrial complexes. The aim of this work is describe the cardiac arrhythmias and electrocardiographic patterns observed in a postoperative period of seven days in a dog with GDV syndrome. Case: A 2-year-old female dog of Fila Brasileiro breed was presented to veterinary hospital due to an acute onset of abdominal distension. Clinical findings included hyperemic mucous membranes, capillary refill time of less than two seconds, normal sounds in cardiac auscultation, heart rate of 160 beats per min, tachypnea, normal femoral pulses and an increased abdominal volume compatible with accumulation of gas. The surgical procedure was the treatment of choice for correction of GDV syndrome. The stomach was dilated, rotated 180 degrees clockwise and possibly with a necrotic area. The spleen was congested and infarcted. During surgery, the patient had a period of low oximetry and two isolated ventricular premature complexes, treated with lidocaine in bolus. In the postoperative period, the electrocardiographic monitoring revealed the presence of two types of arrhythmia. Ventricular tachycardia occurred one day after surgery, being treated with lidocaine in bolus and constant rate infusion. On the third day, the dog developed atrial fl utter, treated with digoxin. On the fourth day, cardiac rhythm returned to normal and showed no further changes up to 7 days after surgery, when the dog was discharged. Discussion: The presence of cardiac arrhythmias in the postoperative period is one of the factors that makes the prognosis worse in dogs with GDV. The etiological mechanism of cardiac arrhythmias in this syndrome has not been elucidated. Among the possibilities are myocardial ischemia, release of myocardial depressant factors, release of catecholamines, electrolyte imbalances and acidosis. Ventricular tachycardia is a relatively common arrhythmia in cases of GDV, which can progress to ventricular fibrillation, the leading cause of deaths from cardiac arrhythmia in dogs with the disease. Among supraventricular arrhythmias, atrial premature complexes were reported, however atrial flutter was not described before in this syndrome. Moreover, the dog developed cardiac arrhythmia until about 72 h after surgery, unlike another reports. An electrocardiographic pattern changed was the size of the P wave, suggesting left atrial enlargement, but thoracic radiography showed a normal-sized cardiac silhouette. Moreover, the animal showed T wave amplitude greater than 25% of the R wave amplitude, which may be related to low oximetry observed at the start of surgery, possible electrolyte imbalances or be physiological. The present case reinforces the importance of electrocardiographic monitoring in the postoperative GDV, including a period of up to 72 h after surgery. Moreover, it is concluded that atrial flutter may be another type of arrhythmia caused by secondary changes of GDV syndrome and confirms the effectiveness of antiarrhythmic therapy with lidocaine in cases of ventricular tachycardia.(AU)

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Background: The external otitis is an inflammatory process that gets at the pinna and the external acoustic meatus of many animals; it can be a pathological process with acute, chronic or still recurrent chronic evolution. In dogs, the external otitis has high clinic importance. This condition could do stenosis or acoustic duct occlusion, inhibiting the ears cleanliness and the application of topical preparations as a way of medical treatment. The vertical acoustic ducts ablation is indicated when all this are ill; however the horizontal duct keeps normal. This employments goal is report a case of ablation at vertical acoustic duct in a male dog, Husky Siberiano race, seven years old which showed chronic and recurrent external otitis. Case: A dog with chronic and recurrent otitis historic and some bids of medicated treatments, without success therapeutic, it was rescued at Hospital of Clínicas Veterinárias at Universidade Federal do Rio Grande do Sul. The owner also reported that the acoustic duct was completely closed and the canine was prostrate and aggressive. In the physical exam was observed stenosis of the right acoustic canal, where had a small orifice, approximately 2 mm, whereby purulent secretion was drained. The patient was submitted to screenings exams like: complete CBC and skull radiography. In the presence of the historic and alterations observed in the clinical exam, it was routed to make an ablation of the vertical acoustic duct. The postoperative consisted of antibiotic, anti-inflammatory and analgesics. External point dehiscence happened, choosing healing it for second intention. At forty-fifth day postsurgical, the canine had already shown completely wounds healing, without secretion by ostium at horizontal auditory duct and without any sign of pain to handle the ear. Discussion: The acoustic ducts stenosis in the canine reported happened because of the chronicle external otitis that can change permanently the size and the external acoustic ducts characteristics. The surgical proceeding made is an alternative technique that has been used when the entire vertical duct is found, grossly, distorted or filled in with a hyperplastic mucosa. The antibiotic used after surgery until the culture result and susceptibility testing it was amoxicillin with clavulanic acid, once which has already known the effectiveness on external and medium otitis treatment. The dehiscence of some points and the wounds infection happened probably cause of the surgical manipulation of inflamed and septic tissues or still cause of the inappropriate dead space closing or inappropriate drainage. It was chosen the healing for second intention using in it an ointment composed by collagenase and chloramphenicol. It was used an ear solution in locus, containing anti-inflammatory, antibacterial and anesthetic to minimize the inflammation, infection and pain at external ear, even after surgical treatment. The discomfort and the pain to manipulate and touch at right ear were obvious on clinical treatment and also what it was identified by the owner like an aggressive animals behavior decreased substantially after the surgical proceeding, could be classified as absent at the revaluation in forty-fifth days postoperative. The vertical portions ablation of the acoustic duct is a technique little used and documented in veterinary medicine, once that has really indications points. The surgical proceeding showed to be important, because allow the secretions drainage, the application of topical agents in the horizontal acoustic duct and the pains control caused by chronicle and recurrent otitis in this patient.(AU)

Assuntos

RESUMO

Background: The external otitis is an inflammatory process that gets at the pinna and the external acoustic meatus of many animals; it can be a pathological process with acute, chronic or still recurrent chronic evolution. In dogs, the external otitis has high clinic importance. This condition could do stenosis or acoustic duct occlusion, inhibiting the ear’s cleanliness and the application of topical preparations as a way of medical treatment. The vertical acoustic duct’s ablation is indicated when all this are ill; however the horizontal duct keeps normal. This employment’s goal is report a case of ablation at vertical acoustic duct in a male dog, Husky Siberiano race, seven years old which showed chronic and recurrent external otitis. Case: A dog with chronic and recurrent otitis historic and some bids of medicated treatments, without success therapeutic, it was rescued at Hospital of Clínicas Veterinárias at Universidade Federal do Rio Grande do Sul. The owner also reported that the acoustic duct was completely closed and the canine was prostrate and aggressive. In the physical exam was observed stenosis of the right acoustic canal, where had a small orifice, approximately 2 mm, whereby purulent secretion was drained. The patient was submitted to screening’s exams like: complete CBC and skull radiography. In the presence of the historic and alterations observed in the clinical exam, it was routed to make an ablation of the vertical acoustic duct. The postoperative consisted of antibiotic, anti-inflammatory and analgesics. External point dehiscence happened, choosing healing it for second intention. At forty-fifth day postsurgical, the canine had already shown completely wound’s healing, without secretion by ostium at horizontal auditory duct and without any sign of pain to handle the ear. Discussion: The acoustic duct’s stenosis in the canine reported happened because of the chronicle external otitis that can change permanently the size and the external acoustic duct’s characteristics. The surgical proceeding made is an alternative technique that has been used when the entire vertical duct is found, grossly, distorted or filled in with a hyperplastic mucosa. The antibiotic used after surgery until the culture result and susceptibility testing it was amoxicillin with clavulanic acid, once which has already known the effectiveness on external and medium otitis treatment. The dehiscence of some points and the wound’s infection happened probably cause of the surgical manipulation of inflamed and septic tissues or still cause of the inappropriate dead space closing or inappropriate drainage. It was chosen the healing for second intention using in it an ointment composed by collagenase and chloramphenicol. It was used an ear solution in locus, containing anti-inflammatory, antibacterial and anesthetic to minimize the inflammation, infection and pain at external ear, even after surgical treatment. The discomfort and the pain to manipulate and touch at right ear were obvious on clinical treatment and also what it was identified by the owner like an aggressive animal’s behavior decreased substantially after the surgical proceeding, could be classified as absent at the revaluation in forty-fifth days postoperative. The vertical portion’s ablation of the acoustic duct is a technique little used and documented in veterinary medicine, once that has really indications points. The surgical proceeding showed to be important, because allow the secretions drainage, the application of topical agents in the horizontal acoustic duct and the pain’s control caused by chronicle and recurrent otitis in this patient.

Assuntos

RESUMO

Background: Gastric-dilation volvulus complex (GDV) is an acute condition characterized by dilation of the stomach associated with rotation around its mesenteric axis. Cardiac arrhythmias, especially of ventricular origin are frequently found in animals with GDV. Ventricular tachycardia is characterized by three or more ventricular premature complexes in sequence. Atrial flutter is a supraventricular arrhythmia uncommon in dogs, characterized by rapid atrial rate and altered atrial depolarization resulting in bidirectional saw-toothed atrial complexes. The aim of this work is describe the cardiac arrhythmias and electrocardiographic patterns observed in a postoperative period of seven days in a dog with GDV syndrome. Case: A 2-year-old female dog of Fila Brasileiro breed was presented to veterinary hospital due to an acute onset of abdominal distension. Clinical findings included hyperemic mucous membranes, capillary refill time of less than two seconds, normal sounds in cardiac auscultation, heart rate of 160 beats per min, tachypnea, normal femoral pulses and an increased abdominal volume compatible with accumulation of gas. The surgical procedure was the treatment of choice for correction of GDV syndrome. The stomach was dilated, rotated 180 degrees clockwise and possibly with a necrotic area. The spleen was congested and infarcted. During surgery, the patient had a period of low oximetry and two isolated ventricular premature complexes, treated with lidocaine in bolus. In the postoperative period, the electrocardiographic monitoring revealed the presence of two types of arrhythmia. Ventricular tachycardia occurred one day after surgery, being treated with lidocaine in bolus and constant rate infusion. On the third day, the dog developed atrial fl utter, treated with digoxin. On the fourth day, cardiac rhythm returned to normal and showed no further changes up to 7 days after surgery, when the dog was discharged. Discussion: The presence of cardiac arrhythmias in the postoperative period is one of the factors that makes the prognosis worse in dogs with GDV. The etiological mechanism of cardiac arrhythmias in this syndrome has not been elucidated. Among the possibilities are myocardial ischemia, release of myocardial depressant factors, release of catecholamines, electrolyte imbalances and acidosis. Ventricular tachycardia is a relatively common arrhythmia in cases of GDV, which can progress to ventricular fibrillation, the leading cause of deaths from cardiac arrhythmia in dogs with the disease. Among supraventricular arrhythmias, atrial premature complexes were reported, however atrial flutter was not described before in this syndrome. Moreover, the dog developed cardiac arrhythmia until about 72 h after surgery, unlike another reports. An electrocardiographic pattern changed was the size of the P wave, suggesting left atrial enlargement, but thoracic radiography showed a normal-sized cardiac silhouette. Moreover, the animal showed T wave amplitude greater than 25% of the R wave amplitude, which may be related to low oximetry observed at the start of surgery, possible electrolyte imbalances or be physiological. The present case reinforces the importance of electrocardiographic monitoring in the postoperative GDV, including a period of up to 72 h after surgery. Moreover, it is concluded that atrial flutter may be another type of arrhythmia caused by secondary changes of GDV syndrome and confirms the effectiveness of antiarrhythmic therapy with lidocaine in cases of ventricular tachycardia.

Assuntos