Adrenal glands of Chinchilla lanigera - study of anatomical features with computed tomography and magnetic resonance imaging

Background: Since chinchilla (Chinchilla lanigera) is frequently used as a laboratory animal, satisfactory data about the imaging anatomical appearance of its adrenal glands, such as their anatomical location and closeness with other abdominal soft tissue and vessels, are important. The aim of this study to determine anatomical features of the chinchilla adrenal gland's using computed tomography and magnetic resonance imaging. Materials, Methods & Results: We used 12 chinchillas (6 males and 6 females), aged 18 months. The animals were in supine recumbency when contrast-enhanced computed tomography (CT) was performed. Transverse, sagittal and dorsal images of the adrenal glands were obtained with iodinated contrast medium, and 3D reconstruction of the obtained images was applied. The craniocaudal (CrCc - length), dorsoventral (DV - height) and lateromedial (LM - width) diameters were measured using an electronic calliper. Magnetic resonance imaging was performed, and coronal T1-weighted images were obtained. The transverse CT anatomical image at the level of the 3rd lumbar vertebra demonstrated the location of the both adrenal glands in accordance with the grey-white scale's variation. The right adrenal gland was hypo-attenuated and elliptic compared to the right kidney and in close contact to it and to the caudal vena cava. The left adrenal gland was oval and at a distance to the abdominal aorta. The dorsal MRI anatomical study of the chinchilla's abdominal organs at a distance of 10 mm from the spine and in a T1-weighted sequence showed that both adrenal glands were retroperitoneal organs. Discussion: Post-contrasted CT defined the topography of both glands. The right adrenal gland has an oval shape and is cranially situated to the left gland, whose shape is cylindrical and elongated. The LM diameter of the right gland is higher than that measured in the left gland. Both DV and CrCc diameters of the right gland are lower compared to those of the left gland. The right adrenal gland is in close contact to the caudal vena cava, the right kidney and the liver, and the left adrenal gland is in a distance to the abdominal aorta. The right adrenal gland was close to the caudal vena cava and the right kidney and medially to the left kidney. The successful comparative analysis of the images in 3D reconstruction and post-contrast CT in 2D allowed us to conclude that 3D reconstruction is suitable to obtain detailed information in a summary form regarding the closeness of the glands and their shape, mainly because the results are in a real time and highly comprehensive. Our data are in in agreement with previous findings about the advantages of 3D reconstruction. The research algorithm applied was based on the dorsal visualization of the glands in T1-weighted sequence, achieving a comprehensive and high-quality MRI imaging of the examined organs in chinchillas. Both adrenal glands were retroperitoneal organs and with low signal. The dorsal MRI anatomical study of the chinchilla's abdominal organs at a distance of 10 mm from the spine and in a T1-weighted sequence showed the whole profile of the right and left glands and the cranial position of the right gland to the left one, the close contact between the right gland and the kidney and the distance between the left gland and the left kidney. The MRI results are detailed and comprehensive for interpretation. In conclusion, the results of the present study are comprehensive, detailed and with high resolution. We present data for the anatomical relationships of the studied organs, their shape and macrometric parameters, concluding that the above mentioned modalities are very important tools for studying the chinchilla's adrenal glands to create a morphological base, which is necessary to investigate specific diseases.

Hemoperitoneum in a cow with lumbar muscle hemangiosarcoma

Background: Hemangiosarcoma is a malignant neoplasm of endothelial cells with an infiltrative growth pattern. Hemangiosarcomas are frequently reported in canines and rare in felines, sheep, goats, swine, horses and cattle. Few cases of hemangiosarcoma were reported in cattle. In the present report, we describe the clinicopathological findings of a bovine muscle hemangiosarcoma. Case: A 6-year-old, Girolando cow from the Dairy Cattle Sector of the Federal Rural University of Rio de Janeiro (UFRRJ), Seropédica, presented sternal decubitus. Clinical signs were markedly pale mucous membranes, moderate dehydration, respiratory distress, and increased heart rate. The hematological examination revealed intense regenerative anemia. Due to the worsening of the clinical condition, the cow was submitted to euthanasia. The necropsy and collection of various fragments of organs were performed, which were sent to the "Setor de Anatomia Patológica" (SAP-UFRRJ). Tissues were fixed in 10 % buffered formalin, routinely processed for histology and stained with Hematoxylin and Eosin (HE). The external mucous membranes were markedly pale. Multifocal areas of 1.5 x 1.0 cm, irregular and dark red were observed dissecting the quadratus lumborum muscle (hemangiosarcoma) fibers. These neoplasms were associated with an extensive cruoric clot adhered to the muscle fibers. The extensive, red, friable mass measured approximately 76 x 55 x 20 cm on the serous surfaces of the organs of the peritoneal cavity (hemoperitoneum). The spleen was moderately reduced. The bone marrow was markedly pale. Histologically, it was observed that there was an extensive proliferation of endothelial cells in the quadratus lumbar muscle mass dissecting the epimysium and perimysium. Endothelial cells had moderate pleomorphism, organized in vascular channels and forming multifocally solid areas with a significant amount of eosinophilic fibrillar material (fibrin). Sections of muscle neoplasm were subjected to immunohistochemistry with anti-von Willebrand factor primary antibody, which showed a multifocal moderate cytoplasmic immunolabeling of neoplastic endothelial cells. Discussion: There are few reports of striated muscle hemangiosarcoma in cattle. Muscular hemangiosarcomas were reported in a 4-month-old calf in the left cervical trapezius muscle and a 6-year-old Holstein cow with left pelvic limb mass lateral and distal to the knee. Some reports presented hemangiosarcoma in the iliopsoas muscle, left cervical trapezius muscle, pelvic limb muscles and right cervical muscle of the bovine. In the presented report, hemoperitoneum occurred as a result of hemorrhages from muscle hemangiosarcoma. Other studies have demonstrated cavity hemorrhages in joint, pelvic, pleural and cranial cavities associated with hemangiosarcoma. Hemangiosarcoma with regenerative anemia must be distinguished from other diseases that cause anemia. The main differential diagnoses of bovine with anemia are vena cava syndrome, coumarin derivatives poisoning, acute poisoning by Pteridium spp., tick fever, anaplasmosis, babesiosis and trypanosomiasis. Hemangiosarcoma should be differentiated from other lesions as hemangioma, vascular tumor of lymphatic endothelium and perivascular wall tumors. Cases with poorly differentiated morphology should be submitted for immunohistochemistry. In the present hemangiosarcoma case, we have used the von Willebrand factor for immunohistochemistry diagnosis. Expression of angiogenic growth factors such as CD31, vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and angiopoietin-1 (Ang-1) have also been used in the diagnosis of vascular proliferation lesions. Hemangiosarcoma in cattle should be included mainly in the differential diagnosis of diseases that cause acute anemia in cattle.

Tamponamento cardíaco secundário ao hemangiossarcoma em cães / Cardiac tamponade secondary to hemangiosarcoma in a dog

Background: Nonspecific clinical manifestations such as apathy, anorexia and diarrhea are common in the clinical routine, and therefore may mask the severity of its triggering factor. When patients presenting this symptomatology are referred to the care center, it is essential that a thorough investigation is performed to clarify the primary causes of these manifestations, and for this, complementary imaging exams may be necessary. The objective of this study is to describe the clinical and imaging aspects of a canine with cardiac hemangiosarcoma and to correlate with the pathophysiology of the alterations observed, in order to optimize the clinical care of patients with nonspecific clinical signs and affected by this alteration. Case: A 10-year-old Pitbull dog was treated with a history of vomiting, loss of appetite and diarrhea. Upon clinical examination, the animal presented dehydration level and distended abdomen. On ultrasound examination, hepatomegaly was observed, associated with signs of double layer in the gallbladder wall and the presence of moderate peritoneal effusion. On chest radiography, the cardiac silhouette showed an important increase in size with loss of shape and contours. Dorsal displacement of the trachea, greater contact of the heart with the sternum and displacement of the caudal vena cava were observed. In addition, an amorphous and poorly defined structure with radiopacity of soft tissues was observed in the region of the atrium and right ventricle, causing the obliteration of pulmonary fields. On echocardiographic examination, a significant amount of free anechogenic fluid was observed in the pericardial sac, confirming the suspicion of pericardial effusion, with consequent collapse of the wall of the right heart chambers during systole. Furthermore, an amorphous, poorly defined and heterogeneous structure was observed in the right atrium wall. Due to the location of the neoformation, the patient's general clinical condition, euthanasia was chosen. During the necropsy, the ocular, oral and preputial mucosae were moderately pale. In the abdomen, the presence of hydroperitoneum and hepatomegaly was observed. In the thoracic cavity, hemothorax, enlarged heart were identified and, in the right atrium, a reddish mass was identified. In addition, the lungs were whitish and hypercrepitating at the edges of the cranial lobes; the rest of the organ was moderately hyperemic, hypocrepitating. In histopathological examination of the liver, the centrilobular region showed chronic passive congestion associated with necrosis and multifocal degeneration of hepatocytes. Neoplastic proliferation of mesenchymal cells, moderately cellular, non-encapsulated, of infiltrative growth was observed in the heart. Neoplastic cells formed bundles, with a tendency to organize themselves into small blood vessels filled with red blood cells. The cytoplasm was moderate, elongated, indistinct, eosinophilic and homogeneous. The nucleus was large, unique, elongated, with finely dotted chromatin and sometimes with one or two nucleoli evident. Anisocytosis, anisocariosis and cell pleomorphism were moderate. Interwoven with neoplastic cells, a moderate presence of multifocal lymphohistioplasmocytic inflammatory infiltrate was observed. The definitive diagnosis of cardiac changes was hemangiosarcoma. Discussion: Hemangiosarcoma is a vascular endothelial cell neoplasm with high metastatic power and unfavorable prognosis. When located in the heart, it is commonly found in the auricle and right atrium and the cardiovascular changes caused by this neoplasm as well as the severity of these changes vary according to size and location. Clinical manifestations can be quite nonspecific and are usually associated with hemodynamic impairment, causing signs of right or left congestive heart failure.

Duplicidad de la vena renal derecha en Didelphis aurita (Didelphimorphia: Didelphidae): reporte de un caso / Double right renal vein in Didelphis aurita (Didelphimorphia: Didelphidae): case report

El Didelphis aurita, conocido como comadreja de orejas negras, es un marsupial con amplia distribución en la América del Sur, frecuente tanto en los ambientes silvestres como antrópicos debido a su gran plasticidad ecológica. Animales de esta especie son comúnmente atendidos en la medicina de animales silvestres y vienen siendo empleados como modelos experimentales alternativos a especies tradicionales. El objetivo de ese trabajo fue relatar la ocurrencia de un caso de vena renal doble en un espécimen adulto, macho, de D. aurita. Para eso, se ha disecado un cadáver fijado y conservado en solución de formaldehído 10%, previamente inyectado con látex de color azul por la porción torácica de la arteria aorta para facilitar la disección. El espécimen poseía dos venas renales derechas, una vena craneal (11,3 mm) y otra caudal (10,0 mm) que drenaban distintamente para una vena cava caudal. La vena renal izquierda y las arterias renales eran únicas. Aunque la duplicidad de la vena renal es reportada en otras especies como perros, gatos y felideos silvestres, este es el primer relato en el género Didelphis. El conocimiento de las variaciones anatómicas vasculares es relevante para la correcta ejecución de procedimientos veterinarios y en la interpretación de hallazgos experimentales en relación con el sistema urogenital.(AU)

Didelphis aurita, known as black eared oposum, is a marsupial widely distributed in South America, frequently seen in both wild and anthropogenic environments due to its great ecological plasticity. This species is commonly treated in wildlife veterinary services and has been used as alternative experimental models instead of conventional species. The aim of this report was to describe a case of double renal vein in a male, adult, specimen of D. aurita. In order to make the dissection easier, the cadaver was fixed and preserved in 10 % formaldehyde solution, and previously injected with latex in blue color by the thoracic aorta to facilitate dissection. The specimen had two right renal veins, one cranial (11.3 mm) and other caudal (10.0 mm) that drained distinctly for caudal vena cava. The left renal vein and the renal arteries were single. Although double renal vein has been reported in other species, such as dogs, cats and wild felids, this is the first mention in the genus Didelphis. The knowledge of the vascular anatomical variations is relevant for the correct execution of veterinary procedures and the interpretation of experimental findings in urogenital system research.(AU)

Osteossarcoma axial intratorácico / Osteosarcoma axial intrathoracic

Background: Bone tumors have a challenging diagnosis and treatment. Osteosarcoma is the name given to a heterogeneous group of malignant, agressive and invasive tumors that often determine bone lysis. Almost all of the animals develop lung metastases, progressing to death. Usually affect the appendicular skeleton, but can also occurs in others areas, although these presentations are rare. Prognosis is always poor. The aim of this paper is to report a case of a dog with osteoblastic osteosarcoma of the sternum, which was diagnosed by computed tomography and histopathologic analysis after excisional biopsy.Case: A male Cocker Spaniel dog, weighing 25 kg, elderly, was examined at the Veterinary Hospital. As main complaint was reported soft swelling on the ventral cervical region causing dyspnea. The patient had previously been medicated with dexamethasone with a significant decrease in the swelling, however recurrence was observed with the cessation of the treatment. Due to the presence of heart murmur, patient underwent to chest radiography and eletrocardiography. Images showed a tumor in the sternal lymph node region, displacing the heart caudally, trachea and esophagus dorsally, causing cranial edema due to a compression of the venous return by the cranial vena cava and subsequent dyspnea. Furosemide (Lasix®) was administered during ambulatorial treatment and prescribed to home, with satisfactory results, with decreased edema and consequent improvement of respiratory symptoms. It was decided to perform computed tomography to better design of the chest structure. The structure located in cranial thoracic region measured about 10.5 cm long x 5.8 cm high x 8.4 cm wide. The patient was undergone to sternotomy to remove the mass that was closely adhered to the sternum and pericardium. The pericardectomy and sternum removal were not performed due to animal being old and present metabolic and cardiopulmonary conditions.[...]

Osteossarcoma axial intratorácico / Osteosarcoma axial intrathoracic

Background: Bone tumors have a challenging diagnosis and treatment. Osteosarcoma is the name given to a heterogeneous group of malignant, agressive and invasive tumors that often determine bone lysis. Almost all of the animals develop lung metastases, progressing to death. Usually affect the appendicular skeleton, but can also occurs in others areas, although these presentations are rare. Prognosis is always poor. The aim of this paper is to report a case of a dog with osteoblastic osteosarcoma of the sternum, which was diagnosed by computed tomography and histopathologic analysis after excisional biopsy.Case: A male Cocker Spaniel dog, weighing 25 kg, elderly, was examined at the Veterinary Hospital. As main complaint was reported soft swelling on the ventral cervical region causing dyspnea. The patient had previously been medicated with dexamethasone with a significant decrease in the swelling, however recurrence was observed with the cessation of the treatment. Due to the presence of heart murmur, patient underwent to chest radiography and eletrocardiography. Images showed a tumor in the sternal lymph node region, displacing the heart caudally, trachea and esophagus dorsally, causing cranial edema due to a compression of the venous return by the cranial vena cava and subsequent dyspnea. Furosemide (Lasix®) was administered during ambulatorial treatment and prescribed to home, with satisfactory results, with decreased edema and consequent improvement of respiratory symptoms. It was decided to perform computed tomography to better design of the chest structure. The structure located in cranial thoracic region measured about 10.5 cm long x 5.8 cm high x 8.4 cm wide. The patient was undergone to sternotomy to remove the mass that was closely adhered to the sternum and pericardium. The pericardectomy and sternum removal were not performed due to animal being old and present metabolic and cardiopulmonary conditions.[...](AU)

Use of total venous inflow occlusion to enable correction of an atrial septal defect in a dog

Background: Atrial septal defects are generally classified into three types: ostium secundum, ostium primum, and sinus venosus. Diagnose is normaly confirmed with Doppler echocardiography, which can identify and classify atrial septal defects types. This cardiac anomaly may be corrected by different surgical approaches, such as cardiopulmonary bypass or transvenous approaches. Therefore, we chose to close the atrial septal defect using a total venous inflow occlusion technique (TIVO), which has been successfully used in other procedures without major postoperative complications, and are notably cheaper and requires no specialized equipment, been able to be done in different places.Case: An American Pit Bull Terrier was referred to our surgical service for ostium secundum atrial septal defect correction, by the time of surgery the patient presented dyspneic; normal capillary refill time and rectal temperature; the owner mentioned the patient exhibited exercise intolerance and delayed development compared to other dogs of the same age or from the same litter. Cardiac auscultation revealed a systolic murmur at the left base, femoral pulse was normokinetic, and patient was emaciated and prostrated at the time of clinical evaluation. Atrial septal defect was suspected and then confirmed by Doppler echocardiography that revealed a discontinuous area in the interatrial septum, and by color doppler images an aliased signal, that extended through the interatrial septum and shunted from the left to the right atria, was visualized, confirming an ostium secundum atrial septal defect. After a right intercostal thoracotomy, a subphrenic pericardiectomy was performed to provide access to the heart. Cranial and caudal vena cava as well as the azygos vein, were dissected, which allowed placement of a Satinsky’s clamp to proceed with TIVO. Before TIVO initiation, a pursestring suture with 3-0 polypropylene was applied to the right atrium.[...]

Use of total venous inflow occlusion to enable correction of an atrial septal defect in a dog

Background: Atrial septal defects are generally classified into three types: ostium secundum, ostium primum, and sinus venosus. Diagnose is normaly confirmed with Doppler echocardiography, which can identify and classify atrial septal defects types. This cardiac anomaly may be corrected by different surgical approaches, such as cardiopulmonary bypass or transvenous approaches. Therefore, we chose to close the atrial septal defect using a total venous inflow occlusion technique (TIVO), which has been successfully used in other procedures without major postoperative complications, and are notably cheaper and requires no specialized equipment, been able to be done in different places.Case: An American Pit Bull Terrier was referred to our surgical service for ostium secundum atrial septal defect correction, by the time of surgery the patient presented dyspneic; normal capillary refill time and rectal temperature; the owner mentioned the patient exhibited exercise intolerance and delayed development compared to other dogs of the same age or from the same litter. Cardiac auscultation revealed a systolic murmur at the left base, femoral pulse was normokinetic, and patient was emaciated and prostrated at the time of clinical evaluation. Atrial septal defect was suspected and then confirmed by Doppler echocardiography that revealed a discontinuous area in the interatrial septum, and by color doppler images an aliased signal, that extended through the interatrial septum and shunted from the left to the right atria, was visualized, confirming an ostium secundum atrial septal defect. After a right intercostal thoracotomy, a subphrenic pericardiectomy was performed to provide access to the heart. Cranial and caudal vena cava as well as the azygos vein, were dissected, which allowed placement of a Satinskys clamp to proceed with TIVO. Before TIVO initiation, a pursestring suture with 3-0 polypropylene was applied to the right atrium.[...](AU)

Aspectos hemodinâmicos da circulação extracorpórea em cães

The cardiopulmonary bypass (CPB) promotes major changes to the body of the patient that needs to be subjected to this procedure, but it can be circumvented or minimized with specific maneuvers for each situation. Despite being an established technique in human medicine, there are still improvements to be achieved. The purposes of this work were to clarify the cardiopulmonary bypass and inform its hemodynamic effects when applied to dogs. Four mongrel healthy dogs were used. The animals were anesthetized and monitored and samples were collected (T0). After that, the animals underwent median sternotomy and cannulation of the aorta and cranial and caudal vena cava and they were kept in CPB for a period of 30 minutes (T1), then disconnected from the CPB machine during 30 minutes in reperfusion process (T2), followed by one hour of reperfusion (T3), and then they were euthanized. The following parameters were evaluated: mean arterial pressure (MAP), central venous pressure (CVP), oxygenation (SaO2) and capnography (ETCO2). MAP, CVP and SaO2 remained within normal limits during the times evaluated. Although the observed average of ETCO2 was low in one of the experimental animals, it maintained the values within the normal range in most experimental animals. We concluded that CPB can be performed in dogs without severe hemodynamic compromise, considering the parameters evaluated in this experiment.

A circulação extracorpórea (CEC) promove alterações graves no organismo do paciente que necessita ser submetido a esse procedimento, que pode, no entanto, ser contornadas ou minimizadas com manobras específicas para cada situação. Apesar de ser uma técnica já estabelecida na medicina humana, ainda existem avanços a serem alcançados. Objetivou-se com este trabalho descrever a técnica de circulação extracorpórea e informar seus efeitos hemodinâmicos quando aplicada em cães. Utilizaram-se quatro cães hígidos, sem raça definida. Os animais foram submetidos à anestesia e monitoramentos e coletas sanguíneas foram realizadas (T0). Em seguida, os animais foram submetidos à esternotomia mediana, canulação da artéria aorta e veias cava cranial e caudal e mantidos por um período de 30 minutos em CEC (T1), foram, depois, desconectados da máquina de CEC, permanecendo por 30 minutos em processo de reperfusão (T2), seguidos de uma hora de reperfusão (T3), sendo, então, eutanasiados. Avaliaram-se os seguintes parâmetros: pressão arterial média, pressão venosa central, oxigenação (SaO2) e capnografia (ETCO2). PAM, PVC e SaO2 permaneceram dentro da normalidade durante os tempos avaliados, já a média observada do ETCO2 estava abaixo apenas em um dos animais experimentais, porém os valores mantiveram-se dentro da normalidade na maioria dos animais experimentais. Concluiu-se que a CEC é possível de ser realizada em cães, sem prejuízos hemodinâmicos graves, considerando-se os parâmetros avaliados neste experimento.

MORFOLOGIA DO CORAÇÃO DE CATETO (Pecari tajacu LINNAEUS, 1758)

Objetivou-se pesquisar a angioarquitetura, forma e localização e, também, aspectos miscroscópicos do sistema de condução do coração de cateto (Pecari tajacu), sendo utilizados 12 animais, 6 machos e 6 fêmeas. Para estabelecimento dos parâmetros topográficos do coração uma incisão foi realizada desde a sincondrose intermandibular à cartilagem xifoide, para remoção do esterno. Os corações foram retirados, dos quais quatro corações foram imersos em solução de formaldeído 10% por 24h para fixação e, posteriormente, feitas secções a fim de expor a face interna. Dois corações tiveram seus sistemas arteriais perfundidos com látex Neoprene (650) amarelo, e dois com acetato de vinil amarelo, estes posteriormente submetidos a corrosão com ácido sulfúrico a 20% por 72h. Foram incluídos em parafina histológica toda a região contendo o ângulo entre a veia cava cranial e átrio direito de dois corações e, dos dois restantes, fragmentos desde a região intercava, até a porção dorsal do septo interventricular, posteriormente, obtidos cortes de 5 m, corados com hematoxilina e eosina (HE). A análise dos dados demostrou que o coração de cateto apresenta forma cônica alongada, ocupa a maior parte do espaço mediastínico médio do tórax e situa-se em região delimitada entre a 3ª e a 6ª costela, envolta pelo pericárdio, este ligado ao diafragma por meio do ligamento frenopericárdico. Do arco aórtico emergem dois ramos colaterais, o tronco braquiocefálico, que se ramifica em artéria subclávia direita e um tronco comum das artérias carótidas comuns direita e esquerda e, em seguida, em artéria subclávia esquerda. Nos modelos arteriais cardíacos a artéria coronária esquerda emergiu da aorta, entre a aurícula esquerda e o tronco pulmonar, e ramificava-se em um ramo superficial que retorna para a aurícula esquerda; um ramo circunflexo, o qual, pelo sulco coronário, circundava a base do coração em direção a face atrial; um ramo oblíquo e o ramo paraconal, que seguia em direção ao ápice. A artéria coronária direita emerge da aorta, entre a aurícula direita e o átrio direito, em seguida, bifurca-se em um ramo superficial que se insere na aurícula direita e no ramo circunflexo direito, que contorna a aurícula direita em direção a face atrial, onde torna-se o ramo subsinuoso, seguindo em direção ao ápice, conferindo ao coração uma vascularização do tipo equilibrada. O nó sinoatrial do cateto foi encontrado na região entre a veia cava cranial e o átrio direito, a nível subepicárdico, não envolvendo a região da junção por completo. É uma estrutura delgada, não encapsulada, envolvida por uma densa malha de tecido conjuntivo frouxo, onde pode-se notar artérias de pequeno calibre e células ganglionares. Os miócitos nodais são menores, com forma arredondada a ovoide e citoplasma menos eosinofílico que o miocárdio atrial, distribuídas como feixes entrelaçados sem nenhuma orientação específica. O nó atrioventricular do cateto está localizado próximo ao local de inserção do folheto septal da válvula tricúspide, numa região subendocárdica, sendo dividido em duas zonas, uma zona compacta e uma zona de transição. A primeira composta por células pequenas e arredondadas, algumas com zonas citoplasmáticas perinucleares transparente, fibroblastos e vasos sanguíneos; a segunda, apresenta células fusiformes, contínuas e organizam-se como uma rede, sendo menores que os miócitos de trabalho.

The objective of this study was to investigate the angioarchitecture, shape and location, as well as the mischroscopic aspects of the collared peccary (Pecari tajacu) heart conduction system, using 12 animals, 6 males and 6 females. To establish the topographic parameters of the heart, an incision was made from intermandibular synchondrosis to xiphoid cartilage to remove the sternum. The hearts were removed from which four hearts were immersed in 10% formaldehyde solution for 24h for fixation and subsequently made sections to expose the inner face. Two hearts had their arterial system perfused with yellow Neoprene (650) latex, and two with yellow vinyl acetate, which were later corroded with 20% sulfuric acid for 72h. The whole region containing the angle between the cranial vena cava and the right atrium of two hearts was included in histological paraffin, and fragments from the remaining two to the dorsal portion of the interventricular septum were obtained, stained with hematoxylin and eosin (HE). The analysis of the data showed the heart of collared peccary has an elongated conical shape, occupies most of the middle mediastinal space of the thorax and is located in a region delimited between the 3rd and 6th rib, surrounded by the pericardium, which is connected to the diaphragm by of the frenopericardial ligament. From the aortic arch emerge two collateral branches, the brachiocephalic trunk, which branches into the right subclavian artery and a common trunk of the right and left common carotid arteries and then into the left subclavian artery. In cardiac arterial models the left coronary artery emerged from the aorta, between the left auricle and the pulmonary trunk, and branched into a superficial branch that returns to the left auricle; a circumflex branch which, through the coronary sulcus, circled the base of the heart toward the atrial face; an oblique branch and the paraconal branch, which ran toward the apex. The right coronary artery emerges from the aorta, between the right atrium and the right atrium, then bifurcates into a superficial branch that inserts into the right auricle and the right circumflex branch, which surrounds the right auricle toward the atrial face, where it becomes the subsinuous branch, moving towards the apex, giving the heart a balanced type vascularization. The sinoatrial node of the catheter was found in the region between the cranial vena cava and the right atrium, at the subepicardial level, not involving the entire junction region. It is a thin, unencapsulated structure, surrounded by a dense mesh of loose connective tissue, where one can notice small arteries and ganglion cells. The nodal myocytes are smaller, with an ovoid round shape and less eosinophilic cytoplasm than the atrial myocardium, distributed as intertwined beams without any specific orientation. The atrioventricular node of the catheter is located near the insertion site of the tricuspid valve septal leaflet, in a subendocardial region, and is divided into two zones, a compact zone and a transition zone. The first consists of small round cells, some with transparent perinuclear cytoplasmic zones, fibroblasts and blood vessels; the second presents continuous fusiform cells and is organized as a network, being smaller than the working myocytes.

Aspectos hemodinâmicos da circulação extracorpórea em cães / Hemodynamic aspects of cardiopulmonary bypass in dogs

The cardiopulmonary bypass (CPB) promotes major changes to the body of the patient that needs to be subjected to this procedure, but it can be circumvented or minimized with specific maneuvers for each situation. Despite being an established technique in human medicine, there are still improvements to be achieved. The purposes of this work were to clarify the cardiopulmonary bypass and inform its hemodynamic effects when applied to dogs. Four mongrel healthy dogs were used. The animals were anesthetized and monitored and samples were collected (T0). After that, the animals underwent median sternotomy and cannulation of the aorta and cranial and caudal vena cava and they were kept in CPB for a period of 30 minutes (T1), then disconnected from the CPB machine during 30 minutes in reperfusion process (T2), followed by one hour of reperfusion (T3), and then they were euthanized. The following parameters were evaluated: mean arterial pressure (MAP), central venous pressure (CVP), oxygenation (SaO2) and capnography (ETCO2). MAP, CVP and SaO2 remained within normal limits during the times evaluated. Although the observed average of ETCO2 was low in one of the experimental animals, it maintained the values within the normal range in most experimental animals. We concluded that CPB can be performed in dogs without severe hemodynamic compromise, considering the parameters evaluated in this experiment.

A circulação extracorpórea (CEC) promove alterações graves no organismo do paciente que necessita ser submetido a esse procedimento, que pode, no entanto, ser contornadas ou minimizadas com manobras específicas para cada situação. Apesar de ser uma técnica já estabelecida na medicina humana, ainda existem avanços a serem alcançados. Objetivou-se com este trabalho descrever a técnica de circulação extracorpórea e informar seus efeitos hemodinâmicos quando aplicada em cães. Utilizaram-se quatro cães hígidos, sem raça definida. Os animais foram submetidos à anestesia e monitoramentos e coletas sanguíneas foram realizadas (T0). Em seguida, os animais foram submetidos à esternotomia mediana, canulação da artéria aorta e veias cava cranial e caudal e mantidos por um período de 30 minutos em CEC (T1), foram, depois, desconectados da máquina de CEC, permanecendo por 30 minutos em processo de reperfusão (T2), seguidos de uma hora de reperfusão (T3), sendo, então, eutanasiados. Avaliaram-se os seguintes parâmetros: pressão arterial média, pressão venosa central, oxigenação (SaO2) e capnografia (ETCO2). PAM, PVC e SaO2 permaneceram dentro da normalidade durante os tempos avaliados, já a média observada do ETCO2 estava abaixo apenas em um dos animais experimentais, porém os valores mantiveram-se dentro da normalidade na maioria dos animais experimentais. Concluiu-se que a CEC é possível de ser realizada em cães, sem prejuízos hemodinâmicos graves, considerando-se os parâmetros avaliados neste experimento.

Aspectos hemodinâmicos da circulação extracorpórea em cães / Hemodynamic aspects of cardiopulmonary bypass in dogs

The cardiopulmonary bypass (CPB) promotes major changes to the body of the patient that needs to be subjected to this procedure, but it can be circumvented or minimized with specific maneuvers for each situation. Despite being an established technique in human medicine, there are still improvements to be achieved. The purposes of this work were to clarify the cardiopulmonary bypass and inform its hemodynamic effects when applied to dogs. Four mongrel healthy dogs were used. The animals were anesthetized and monitored and samples were collected (T0). After that, the animals underwent median sternotomy and cannulation of the aorta and cranial and caudal vena cava and they were kept in CPB for a period of 30 minutes (T1), then disconnected from the CPB machine during 30 minutes in reperfusion process (T2), followed by one hour of reperfusion (T3), and then they were euthanized. The following parameters were evaluated: mean arterial pressure (MAP), central venous pressure (CVP), oxygenation (SaO2) and capnography (ETCO2). MAP, CVP and SaO2 remained within normal limits during the times evaluated. Although the observed average of ETCO2 was low in one of the experimental animals, it maintained the values within the normal range in most experimental animals. We concluded that CPB can be performed in dogs without severe hemodynamic compromise, considering the parameters evaluated in this experiment.(AU)

A circulação extracorpórea (CEC) promove alterações graves no organismo do paciente que necessita ser submetido a esse procedimento, que pode, no entanto, ser contornadas ou minimizadas com manobras específicas para cada situação. Apesar de ser uma técnica já estabelecida na medicina humana, ainda existem avanços a serem alcançados. Objetivou-se com este trabalho descrever a técnica de circulação extracorpórea e informar seus efeitos hemodinâmicos quando aplicada em cães. Utilizaram-se quatro cães hígidos, sem raça definida. Os animais foram submetidos à anestesia e monitoramentos e coletas sanguíneas foram realizadas (T0). Em seguida, os animais foram submetidos à esternotomia mediana, canulação da artéria aorta e veias cava cranial e caudal e mantidos por um período de 30 minutos em CEC (T1), foram, depois, desconectados da máquina de CEC, permanecendo por 30 minutos em processo de reperfusão (T2), seguidos de uma hora de reperfusão (T3), sendo, então, eutanasiados. Avaliaram-se os seguintes parâmetros: pressão arterial média, pressão venosa central, oxigenação (SaO2) e capnografia (ETCO2). PAM, PVC e SaO2 permaneceram dentro da normalidade durante os tempos avaliados, já a média observada do ETCO2 estava abaixo apenas em um dos animais experimentais, porém os valores mantiveram-se dentro da normalidade na maioria dos animais experimentais. Concluiu-se que a CEC é possível de ser realizada em cães, sem prejuízos hemodinâmicos graves, considerando-se os parâmetros avaliados neste experimento. (AU)

Estrutura, ultraestrutura e morfometria da veia cava de paca (Cuniculus paca Linnaeus, 1766) criada em cativeiro / Structure, ultrastructure and morphometry of the Vena cava in the paca (Cuniculus paca Linnaeus, 1766) raised in captivity

A paca (Cuniculus paca) é o segundo maior roedor da fauna brasileira. Apresenta carne de excelente qualidade, o que incentiva a criação comercial. Além disso, este animal pode tornar-se uma opção válida em experimentação embora poucas sejam as informações detalhadas sobre sua morfologia. Assim, objetivou-se descrever a morfologia, morfometria e ultraestrutura de segmentos das porções cranial e caudal da veia cava de quatro pacas (Cuniculus paca) adultas excedentes do plantel do Setor de Animais Silvestres do Departamento de Zootecnia da FCAV-Unesp. Os segmentos venosos foram analisados à microscopia de luz e à microscopia eletrônica de varredura. Foram mensuradas as espessuras do complexo formado pelas túnicas íntima e média, além da túnica adventícia e analisou-se os resultados pela estatística descritiva, teste "T" pareado (p<0,05). Em relação à espessura das túnicas estudadas, comprovou-se que os valores da espessura das túnicas íntima, média e adventícia, para todos os animais, foram significativamente maiores no segmento cranial. As camadas das paredes dos vasos apresentaram variações entre si quanto à estrutura e espessura, supostamente devido a uma adaptação à exigência funcional.(AU)

The paca (Cuniculus paca) is the second largest rodent of the Brazilian fauna. The excellent meat quality of this specie encourages the development of their commercial production. Moreover, this animal can become a viable alternative for animal experimentation although there exists scarce detailed information concerning their morphology. Therefore the purpose of this study is to describe the morphology, morphometry and ultrastructure in segments of the cranial and caudal portions of vena cava in four adult males and females of Cuniculus paca from the squad of Wild Animals Sector of Animal Science Department of FCAV-Unesp. Parts of the segments were examined by light microscopy and part by scanning electron microscopy. Thickness measures of the tunica intima and media complex and tunica adventitia of the vena cava were taken and analyzed using "T" test (p<0.05). In vena cava the thickness values of the intima, media and adventitia, for all animals, were significantly higher in the cranial segment. The layers of the vessel walls showed variations in structure and thickness, presumably due to an adaptation to functional demand.(AU)

Thoracic and heart biometrics of non-anesthetized agouti (Dasyprocta primnolopha Wagler, 1831) measured on radiographic images / Biometria torácica e cardíaca de cutias não anestesiadas (Dasyprocta primnolopha Wagler, 1831) mensuradas em imagens radiográficas

The agouti is a species intensively hunted throughout the Amazon and the semi-arid regions of northeastern Brazil. Considering the current trend in conservation management of wild species, the aim of this study was to determine the morphometric reference to the heart of agouti raised in captivity, based on thoracic and cardiac measurements in these animals. Thirty adult agoutis, 1 to 3 years of age, without clinical signs of cardiac disease were selected. The animals were physically restrained and radiographies in laterolateral (LL) and ventrodorsal (VD) recumbence were produced. The following measures were taken: the apicobasilar length of the heart (at the most cranial height of the Carina region to the heart apex) (AB), maximum width of the heart perpendicular to AB (CD), heart inclination angle (AIC), trachea inclination angle (AIT), distance from the right heart wall (DPTd), distance from the left heart wall (DPTe) and vertical depth of the thorax, and the ventral face of the vertebral column to the dorsal border of the sternum at the level of the trachea bifurcation (H). The ratios between AB/CD, AB/H and CD/H were also analyzed. To calculate the vertebral heart scale (VHS), the AB and CD measurements were laid over the thoracic vertebra starting at T4. Radiographic evaluation showed values consistent with those reported in small animals and some wild and exotic species. The main biometric values in the chest cavity and heart of agouti are arranged as follows: (1) The ratios between AB/H ratio and CD/H were not sensitive for identifying heart increases (p>0.05), while the ratio AB/CD was more sensitive in this identification (p<0.05); (2) AIC: 21.2±6.4º (mean between male and famale); (3) AIT for males and females: 9.93±3.23° and 8.4±3.94°; (4) DPTd and DPTe for males: 0.97±0.40cm and 0.7±0.30cm; (5) DPTd and DPTe for females: 1.12±0.42cm and 01.02±0.43cm; (6) VHS for males and females: 7.75±0.48v e 7.61±0.34v; (7) The caudal vena cava (CVC) was visualized dorsal-cranially and located right of the midline. The data obtained allowed the acquisition of the first reference values for biometry of the heart of agoutis, contributing to better understanding of cardiac morphology and identification of cardiomyopathy in these animals.(AU)

A cutia é uma espécie intensamente caçada em toda a Amazônia e nas regiões semi-áridas do Nordeste do Brasil. Considerando a tendência atual em gestão de conservação das espécies selvagens, o objetivo deste estudo foi determinar referências morfométricas para o coração de cutia criadas em cativeiro, com base em medições torácicas e cardíacas desses animais. Foram selecionados 30 cutias adultas, sem sinais clínicos de doença cardíaca, com idade entre 1 a 3 anos. Os animais foram contidos fisicamente e realizadas projeções radiográficas laterolaterais e (LL) e ventrodorsais (VD). As seguintes medidas foram tomadas: O comprimento apicobasilar do coração (na altura mais cranial da região carina até o ápice do coração) (AB); a largura máxima coração perpendicular a AB (CD); o ângulo de inclinação do cardíaca (AIC); ângulo de inclinação da traquéia (AIT); a distância a partir da parede direita do coração (DPTd); a distância a partir da parede esquerda do coração (DPTe) e profundidade vertical do tórax, da face ventral da coluna vertebral até à borda dorsal do esterno, no nível da bifurcação da traqueia (H). As relações entre AB/CD, AB/H e CD/H também foram analisadas. Para calcular o "vertebral heart scale" (VHS), as medidas AB e CD foram colocadas sob as vértebras torácicas a partir de T4. A avaliação radiográfica demonstrou valores consistentes com aqueles relatados em pequenos animais e algumas espécies selvagens e exóticos. Os principais valores biométricos mensurados na cavidade torácica e cardíaca da cutia, estão dispostas da seguinte forma: (1) As relações entre AB/H e CD/H não foram sensíveis para identificar aumento do coração (p> 0,05), enquanto a proporção AB/CD foi mais sensível nesta identificação (p <0,05); (2) AIC: 21,2 ± 6.4º (média entre machos e fêmeas); (3) AIT para machos e fêmeas: 9.93 ± 3.23° and 8.4±3.94°; (4) DPTd e DPTe para os machos: 0,97 ± 0,40 cm e 0,7 ± 0,30, (5) DPTd e DPTe para as fêmeas: 1,12 ± 0,42 e 01,02 ± 0,43; (6) VHS para machos e fêmeas: 7.75±0.48v e 7.61±0.34v; (7) A veia cava caudal (CVC) foi visualizada dorso-cranialmente e localizada à direita da linha média. Os dados obtidos permitiram a obtenção dos primeiros valores de referência para a biometria do coração de cutias, contribuindo para uma maior compreensão da morfologia cardíaca e identificação de cardiomiopatia nestes animais.(AU)

Avaliação morfométrica e hemodinâmica comparativa dos vasos envolvidos no shunt portossistêmico congênito em cães / Morphometric and haemodynamic evaluation of the vessels associated with the congenital portosystemic shunting in dogs

The morphometry and haemodynamic aspects of portal vein were studied in 20 normal dogs with less than 120 days of age and in 14 dogs presenting portosystemic shunting with ages between 90 and 360 days. In the control group the hepatic margins were seen 1.50cm to 3.00cm caudal to the costal margin. Collected data indicated that the mean diameter of portal vein (VP), caudal vena cava (VCC) and abdominal aorta (AO) measured respectively, 0.38cm, 0.37cm and 0.41cm. The VP/VCC and VP/AO mean ratios were respectively, 1.10 and 0.94. The average of VP, VCC and AO areas were respectively, 0.12cm², 0.11cm² and 0.14cm². The haemodynamic of portal vein was studied by ultrasound Doppler and the mean velocity of portal blood flow (VMFSP) measured was 17.76cm/s. It was verified that portal blood flow (FSP) average was 83.11ml/min/kg and the congestion index (IC) average was 0.006. In the group of animals presenting portosystemic shunting, the hepatic margins were seen 1.00cm to 2.00cm cranial to the costal margin. The morphometry of VP, VCC and AO presented a mean diameter of 0.40cm, 0.74cm and 0.56cm, respectively. The VP/VCC and VP/AO mean ratios were respectively, 0.54 and 0.69. The average of VP, VCC and AO areas were respectively, 0.14cm², 0.31cm² and 0.25cm². The haemodynamic study demonstrated that the VMFSP measured was 22.29cm/s and the IC average was 0.006.(AU)

Foram realizados o estudo morfométrico e o estudo hemodinâmico da veia porta em vinte cães clinicamente normais, de idade igual e inferior a 120 dias e em quatorze cães portadores de shunt portossistêmico, de idades entre 90 e 360 dias. Nos cães do grupo controle, as margens hepáticas apresentaram-se entre 1,50cm e 3,00cm caudalmente à margem costal. Os diâmetros médios da veia porta (VP), veia cava caudal (VCC) e aorta abdominal (AO) obtidas foram respectivamente, 0,38cm, 0,37cm e 0,41cm. As proporções entre os diâmetros médios VP/VCC e VP/AO apresentaram médias de 1,10 e 0,94, respectivamente. As médias das áreas da VP, VCC e AO resultaram respectivamente em 0,12cm² , 0,11cm² e 0,14cm². No estudo hemodinâmico da VP destes animais, utilizando-se o ultrassom Doppler, a velocidade média de fluxo sangüíneo portal (VMFSP) mediu 17,76cm/s. A média de fluxo sangüíneo portal (FSP) resultou em 83,11ml/min/kg. O índice de congestão (IC) apresentou média de 0,006. Para o grupo de cães portadores de shunt portossistêmico, o fígado apresentou redução de seu volume, sendo as margens hepáticas visibilizadas entre 1,00cm e 2,00cm cranialmente à margem costal. No estudo morfométrico, as médias dos diâmetros médios obtidos de VP, VCC e AO resultaram respectivamente em 0,40cm, 0,74cm e 0,56cm. As proporções entre os diâmetros médios VP/VCC e VP/AO resultaram respectivamente em 0,54 e 0,69. As médias das áreas de VP, VCC e AO resultaram respectivamente em 0,14cm², 0,31cm² e 0,25cm². Ao ultrassom Doppler a VMFSP mediu 22,29cm/s e a média do IC da VP obtido foi de 0,006.(AU)

Persistência da veia cava cranial esquerda em cão / Persistent Left Cranial Vena Cava in a Dog

Background: Persistent left cranial vena cava with absent right cranial vena cava is a rare anomaly. Congenitally persistent left cranial vena cava is the most common variant of the systemic venous return to the heart, embryologically resulting from failure of the anterior cardinal vein in becoming obliterated. Persistent left cranial vena cava is the most common form of anomalous venous drainage involving the cranial vena cava, and represents persistence of the left horn of the embryonic sinus venosus, which normally involutes during normal development, becoming the coronary sinus. Usually, persistent left cranial vena cava enters the right atrium through the orifice of an enlarged coronary sinus. Persistent left cranial vena cava is an uncommon congenital cardiovascular anomaly in dogs, generally coexisting with other more serious cardiac defects. The condition is rare as an isolated single defect. The left cranial vena cava is observed only among domestic mammals, but it is a relatively rare anomaly that can be found in other species, including man, without causing clinical problems. The objective of this study was to report the occurence of a rare vascular formation of the cranial vena cava, which caused the persistence of the left cranial vena cava instead of the right one. Case: At the anatomy laboratory of the Faculty of Veterinary of the UFGRS, a male dog was identified with a persistent left cranial vena cava and absent right cranial vena cava.[...]

Persistência da veia cava cranial esquerda em cão / Persistent Left Cranial Vena Cava in a Dog

Background: Persistent left cranial vena cava with absent right cranial vena cava is a rare anomaly. Congenitally persistent left cranial vena cava is the most common variant of the systemic venous return to the heart, embryologically resulting from failure of the anterior cardinal vein in becoming obliterated. Persistent left cranial vena cava is the most common form of anomalous venous drainage involving the cranial vena cava, and represents persistence of the left horn of the embryonic sinus venosus, which normally involutes during normal development, becoming the coronary sinus. Usually, persistent left cranial vena cava enters the right atrium through the orifice of an enlarged coronary sinus. Persistent left cranial vena cava is an uncommon congenital cardiovascular anomaly in dogs, generally coexisting with other more serious cardiac defects. The condition is rare as an isolated single defect. The left cranial vena cava is observed only among domestic mammals, but it is a relatively rare anomaly that can be found in other species, including man, without causing clinical problems. The objective of this study was to report the occurence of a rare vascular formation of the cranial vena cava, which caused the persistence of the left cranial vena cava instead of the right one. Case: At the anatomy laboratory of the Faculty of Veterinary of the UFGRS, a male dog was identified with a persistent left cranial vena cava and absent right cranial vena cava.[...](AU)

comportamento da frequência cardíaca e da temperatura corpórea em coelhos submetidos à parada circulatória cardíaca / Behavior of heart rate and temperature in rabbits submitted to circulatory arrest

A técnica da parada circulatória total (PTC) ou inflow occlusion consiste em impedir a entrada do sangue às câmaras cardíacas através do clampeamento das veias cavas caudal e cranial e veia ázigos. Contudo, alterações nos parâmetros fisiológicos do paciente podem ser desencadeadas com a aplicação desta técnica. Em enfermidades cardíacas intracavitárias, cuja correção leva alguns minutos, como na estenose pulmonar ou na estenose subaórtica, esta técnica pode ser facilmente utilizada. Por ser de baixo custo e de simples aplicação, é passível de realização em clínicas particulares. Neste ensaio, avaliou-se o comportamento da frequência cardíaca e da temperatura corpórea de coelhos submetido a dois períodos de cinco minutos de PCT, utilizando-se a técnica da inflow occlusion. Um período de recirculação sanguínea entre as oclusões foi realizado a fim de verificar os potenciais benefícios desta prática sobre o comportamento da frequência cardíaca e temperatura corpórea dos animais, parâmetros avaliados ao longo de todo o período transoperatório. Ocorreram dois óbitos, ambos no período de recirculação, dada a ocorrência de fibrilação ventricular. Todavia, com a aplicação do período de recirculação do sangue, foi possível constatar que esta técnica pode ser utilizada em cirurgias intracardíacas, com duração de até dez minutos.

The technique of total circulatory arrest (TCA), or inflow occlusion, consists in preventing the blood entry into the heart chambers by clamping the vena cava and the cranial and caudal vena azygos. However, changes in physiological parameters of the patient can be triggered with the application of this technique. This technique can be easily used in heart intra-cavity diseases, whose correction takes a few minutes, as in pulmonary stenosis or subaortic stenosis. Because low cost and simple implementation, it may be carried out in private clinics. In this trial, the behavior of heart rate and body temperature of rabbits submitted to two periods of five minutes of TCA, by the use of inflow occlusion technique, was evaluated. A period of blood recirculation between occlusions was performed to verify the potential benefits of this practice on the behavior of heart rate and body temperature of the animals. These parameters were assessed throughout the perioperative period. There were two deaths, both in the recirculation period due to the occurrence of ventricular fibrillation. Nevertheless, with the implementation of the period of blood recirculation, we verified that this technique can be used in intra-cardiac surgery lasting up to 10 minutes.

comportamento da frequência cardíaca e da temperatura corpórea em coelhos submetidos à parada circulatória cardíaca / Behavior of heart rate and temperature in rabbits submitted to circulatory arrest

A técnica da parada circulatória total (PTC) ou inflow occlusion consiste em impedir a entrada do sangue às câmaras cardíacas através do clampeamento das veias cavas caudal e cranial e veia ázigos. Contudo, alterações nos parâmetros fisiológicos do paciente podem ser desencadeadas com a aplicação desta técnica. Em enfermidades cardíacas intracavitárias, cuja correção leva alguns minutos, como na estenose pulmonar ou na estenose subaórtica, esta técnica pode ser facilmente utilizada. Por ser de baixo custo e de simples aplicação, é passível de realização em clínicas particulares. Neste ensaio, avaliou-se o comportamento da frequência cardíaca e da temperatura corpórea de coelhos submetido a dois períodos de cinco minutos de PCT, utilizando-se a técnica da inflow occlusion. Um período de recirculação sanguínea entre as oclusões foi realizado a fim de verificar os potenciais benefícios desta prática sobre o comportamento da frequência cardíaca e temperatura corpórea dos animais, parâmetros avaliados ao longo de todo o período transoperatório. Ocorreram dois óbitos, ambos no período de recirculação, dada a ocorrência de fibrilação ventricular. Todavia, com a aplicação do período de recirculação do sangue, foi possível constatar que esta técnica pode ser utilizada em cirurgias intracardíacas, com duração de até dez minutos.(AU)

The technique of total circulatory arrest (TCA), or inflow occlusion, consists in preventing the blood entry into the heart chambers by clamping the vena cava and the cranial and caudal vena azygos. However, changes in physiological parameters of the patient can be triggered with the application of this technique. This technique can be easily used in heart intra-cavity diseases, whose correction takes a few minutes, as in pulmonary stenosis or subaortic stenosis. Because low cost and simple implementation, it may be carried out in private clinics. In this trial, the behavior of heart rate and body temperature of rabbits submitted to two periods of five minutes of TCA, by the use of inflow occlusion technique, was evaluated. A period of blood recirculation between occlusions was performed to verify the potential benefits of this practice on the behavior of heart rate and body temperature of the animals. These parameters were assessed throughout the perioperative period. There were two deaths, both in the recirculation period due to the occurrence of ventricular fibrillation. Nevertheless, with the implementation of the period of blood recirculation, we verified that this technique can be used in intra-cardiac surgery lasting up to 10 minutes.(AU)

Tratamento cirúrgico da dirofilariose canina utilizando a a triotomia direita através da inflow occlusion: relato de caso / The surgical treatment of the heartworm disease in the dog using the technique of right atriotomy through the inflow occlusion: a case report

A dirofilariose é uma doença com distribuição mundial, causada pelo parasita Dirofilária immitis. Esta doença apresenta importância zoonótica, pois os humanos também podem ser infectados, mas são considerados hospedeiros acidentais, sendo o cão um dos hospedeiros definitivos. Em cães a gravidade da doença esta relacionada ao número de parasitas adultos, que são frequentemente encontrados no coração e pulmão. Este parasita se aloja principalmente na artéria pulmonar e no átrio direito, podendo levar a uma insuficiência cardíaca congestiva direita. O diagnóstico é dado através da utilização do teste de ELISA, exame eco cardiográfico e pesquisa de microfilárias na circulação sanguínea. A maioria dos animais infectados são assintomáticos. Porém dentre os animais sintomáticos podemos observar letargia, tosse e distensão abdominal devido a ascite. Outros sinais incluem perda de peso, caquexia, anemia, dispnéia, intolerância ao exercício e morte devido à insuficiência cardíaca congestiva direita. O tratamento clínicopara a dirofilariose consiste em terapia adulticida ou microfilaricida. No entanto nos casos em que há uma carga parasitária muito grande e/ou o animal manifesta a síndrome da veia cava cranial o tratamento cirúrgico torna-se o mais recomendado. O presente artigo visa relatar o tratamento da dirofilariose em um cão utilizando a técnica de atriotomia direita através da inflow occlusion.AU

The heartworm disease is a disease with global distribution, caused by the parasite Dirofilária immitis. This disease presents a zoonotic relevance, because humans can be also infected, but are considered accidental hosts, being dogs one of the definitive hosts. In dogs the disease severity is related to the number of adult parasites, are the often found in the heart and lung. This parasite lodges primarily in the pulmonary artery and in the right atrium, and may induce a right congestive cardiac insufficiency. The diagnosis is given through the utilization of the ELISA test, echocardiography exam and search of microfilaries in the blood circulation. The majority of infected animals are asymptomatics. However, among the symptomatic dogs can be observed lethargy, cough, abdominal distention due the ascites. Others signals include weight loss, cachexy, anemia, dyspnea, exercise intolerance, and death due the right congestive cardiac insufficiency. The clinical treatment to the heartworm disease consists in a adulticide and microfilaricide. However in cases that there is a very high parasitic load and/or the animal manifests the cranial vena cava syndrome the surgical treatment becomes the most recommended. The present article aim to relate the treatment of the heartworm disease in a dog, using the technique of right atriotomy through the inflow occlusion.AU