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Caudal Vena Cava (caudal + vena_cava)
Selected AbstractsOrigin of the Infrarenal Part of the Caudal Vena cava in the PigANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 5 2008P. Cornillie Summary The vascular topography in the lumbar region of pig embryos and young fetuses was three-dimensionally reconstructed to study some controversial aspects of the origin and development of the infrarenal part of the caudal vena cava. Contrary to general belief, it was found that the supracardinal veins, which form the azygos veins in the thorax, do not take part in the construction of the caudal vena cava in the lumbar region. These veins do appear in the abdomen, but they are only involved in the formation of the lumbar and ascending lumbar veins. The infrarenal part of the caudal vena cava arises from the lumbar part of the right caudal cardinal vein. Whilst this venous pattern is established, the lumbar part of the left caudal cardinal vein disappears and its former location is occupied by large lymphatic connections between the cysterna chyli and the retroperitoneal mesenteric lymphatic sac. On the basis of these findings, a number of hypotheses on the development of anatomical variations of the caudal vena cava should be reconsidered. [source] Management of cor triatriatum dexter by balloon dilatation in three dogsJOURNAL OF SMALL ANIMAL PRACTICE, Issue 1 2004M. Stafford Johnson Two dogs, one immature and one adult, were presented with a history of progressive ascites. In a third, immature dog, increasing exercise intolerance had been noted. Echocardiography demonstrated a partition in the right atrium (cor triatriatum dexter) and echocontrast studies documented normal flow from the cranial vena cava into the right atrium and ventricle. A saphenous vein contrast study demonstrated flow from the caudal vena cava into an accessory right atrial chamber (sinus venarum). The sinus venarum communicated with the true right atrium via a small defect in the atrial membrane in one dog, and additionally with the left atrium via a right-to- left shunting foramen ovale in the other dogs. All defects were visualised on angiographic studies by selective catheterisation of the caudal vena cava via the femoral vein. Balloon dilatation of the defect was then performed using a small followed by a larger balloon angioplasty catheter to enlarge the defect in the atrial membrane. Clinical signs improved within days and were sustained in the long term in all cases. [source] Canine leishmaniasis with nephrotic syndrome and aortic and caudal vena cava thromboembolismJOURNAL OF VETERINARY EMERGENCY AND CRITICAL CARE, Issue 5 2008Nuno Félix DVM Abstract Objective , To describe a case of leishmaniasis associated with nephrotic syndrome and aortic and caudal vena cava thrombosis in a dog. Case Summary , A 3-year-old male Boxer was referred to the Faculty of Veterinary Medicine, Lisbon, with vomiting, polyuria, polydipsia, lethargy, anorexia, and weight loss. On admission, the dog was thin, quiet, and dehydrated. Initial laboratory abnormalities were compatible with a diagnosis of leishmaniasis (confirmed by serology and bone marrow aspirate), and nephrotic syndrome. Three days later, the animal developed lumbar pain, paraparesis, and absent femoral pulses. Coagulation tests showed a marked reduction in antithrombin (AT) and a mild increase in serum fibrinogen concentration. A diagnosis of thromboembolism was made. In spite of treatment aimed at controlling the primary condition and decreasing further thrombus formation, necrosis developed in the distal right pelvic limb and the nail beds of the left pelvic limb. Against medical advice, medication was stopped and, 15 days later, the dog returned to the hospital, showing extensive necrosis of both pelvic limb extremities. Euthanasia was performed at the owner's request. Necropsy showed a thrombus localized at the distal aorta and extending into the right iliac artery, and an additional thrombus extending from both femoral veins onto the caudal vena cava. New or Unique Information Provided , Thromboembolic disease is rare in dogs with leishmaniasis with nephrotic syndrome. This case suggests that a marked decrease in AT and a mild increase in serum fibrinogen may elicit a hypercoagulable state in these patients. [source] Budd,Chiari-like syndrome in a dog with a chondrosarcoma of the thoracic wallJOURNAL OF VETERINARY EMERGENCY AND CRITICAL CARE, Issue 2 2007Megan F. Whelan DVM Abstract Objective: To describe a dog with Budd,Chiari-like syndrome secondary to caudal vena cava compression from a thoracic wall chondrosarcoma. Case summary: A 9-year-old spayed female Shetland Sheepdog cross with a recent history of non-productive cough developed severe abdominal distension and dyspnea. Marked ascites and enlarged hepatic veins were identified with ultrasonography. At surgery, a right thoracic wall mass was found to be compressing the caudal vena cava. Fluid analysis of the ascites revealed a modified transudate with elevated protein concentration, consistent with Budd,Chiari-like syndrome. Clinical signs resolved following thoracotomy and complete resection of the mass. New or unique information provided: Obstruction of venous blood flow can result from compression exerted by a space-occupying thoracic wall mass on the caudal vena cava. Clinical resolution can be achieved with return of adequate venous circulation by removal of the mass and alleviation of the external pressure. [source] Three-dimensional reconstruction of the remodeling of the systemic vasculature in early pig embryosMICROSCOPY RESEARCH AND TECHNIQUE, Issue 2 2008Pieter Cornillie Abstract Current research on angiogenesis and vascular regression is mainly focused on pathological conditions such as tumor growth and diabetic retinopathy, while a suitable physiological model to study the controlling factors in these processes is still lacking. The remodeling pattern of the embryonic vasculature into the adult configuration, such as the branchial arch arterial system developing into the aorta or the early embryonic veins building the caudal vena cava can potentially serve as a model. However, practical applications of the embryonic vascular patterning are impeded by the current controversy over the exact development of the caudal vena cava in mammals. To elucidate these ambiguities, specific developmental stages of vascular development in pig embryos were mapped by means of computer-assisted 3D reconstructions starting from histological serial sections of Bouin's fixed embryos. Special attention was given to venous segments in the lumbar region, as their origin and fate are equivocally described in literature. Here we demonstrate that these venous segments originate from the caudal cardinal veins which are forced to migrate during development into a more dorsal position due to the expansion of the developing metanephroi and the more dorsal relocation of the umbilical arteries. These findings are in contrast with the generally accepted theory that the venous segments in the lumbar region arise from newly formed veins that are located dorsal to the early caudal cardinal system. Microsc. Res. Tech., 2008. © 2007 Wiley-Liss, Inc. [source] Morphology of Haemal Nodes in the Roe Deer (Capreolus capreolus)ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 5 2010Y. Akaydin Bozkurt With 5 figures Summary The present study was aimed at the determination of the morphology of haemal nodes in the roe deer (Capreolus capreolus). The morphology of haemal nodes located in the abdominal and thoracic cavities of six roe deer (two adult male, two adult female and two foetuses) was studied by gross inspection and histological methods. Oval- and round-shaped haemal nodes with colours varying from pink to dark red were observed particularly between the abdominal aorta and caudal vena cava, and at the beginning of the main branches of the abdominal aorta. These nodes, having connection only with blood vessels, were covered with a thin or thick capsule of connective tissue in the foetus and the adult respectively. Trabeculae were not observed in foetal nodes. In adults, the capsule, trabeculae and, in particular, the sinuses were strongly supported by reticular fibres and cells. The morphology of these nodes displayed similarity to that of other ruminant species. [source] Histological Assessment of Selected Blood Vessels of the Phocid Seals (Northern Elephant and Harbour Seals)ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 3 2010H. Smodlaka Summary Phocid seals exhibit vascular adaptations that allow them to undertake prolonged deep dives. These vascular adaptations are either unique to phocids, or are modified vascular equivalents to those present in terrestrial mammals. One such adaptation, the aortic bulb, is a spherical enlargement of the ascending aorta specific to phocid seals. Its histological make-up consists of a reinforced tunica media with circular and longitudinal layers of elastic fibres. This reinforcement enables multi-axial deformation of the aortic bulb, thus complementing its function as a prominent elastic reservoir or ,windkessel'. A second adaptation, the hepatic sinus, is an asymmetrical dilation of the abdominal portion of the caudal vena cava and accompanying hepatic veins. The hepatic sinus is comprised of a relatively thin tunica media, with a scant smooth muscle component. The bulk of the sinus wall is comprised of tunica adventitia. A third vascular adaptation distinctive to the phocids is the pericardial venous plexus, composed of convoluted veins circumnavigating the perimeter of the heart. Microscopically, these veins have a thick tunica media and also contain valves. Smaller arteries, venules and distinct capillary beds are observed interspersed in-between these veins. It can be hypothesized, that in seals, certain vascular embryonic development may be arrested at an earlier embryonic stage, resulting in these unusual vascular formations. These modifications play a vital role in blood pressure regulation and distribution of oxygenated blood during prolonged deep diving. The purpose of this work was to elucidate the histological aspects of these unique vascular modifications and relate them to specific function. [source] Macroscopic Anatomy of the Great Vessels and Structures Associated with the Heart of the Ringed Seal (Pusa hispida)ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 3 2009H. Smodlaka Summary The ringed seal [Pusa (Phoca) hispida], as well as other seals, exhibits unique anatomical properties when compared to its terrestrial counterparts. In the ringed seal, the most conspicuous marine adaptation is the aortic bulb. This large dilatation of the ascending aorta is comparable to that found in other seal species and marine mammals. The branches of the ascending aorta (brachiocephalic trunk, left common carotid artery and left subclavian artery) are similar to those of higher primates and man. The peculiarities of the venous system are: three pulmonary veins, a pericardial venous plexus, a caval sphincter, a hepatic sinus with paired caudal vena cavae and a large extradural venous plexus. Generally, three common pulmonary veins (right, left and caudal) empty into the left atrium. The pericardial venous plexus lies deep to the mediastinal pericardial pleura (pleura pericardica) on the auricular (ventral) surface of the heart. The caval sphincter surrounds the caudal vena cava as it passes through the diaphragm. Caudal to the diaphragm, the vena cava is dilated (the hepatic sinus), and near the cranial extremity of the kidneys, it becomes biphid. The azygos vein is formed from the union of the right and left azygos veins at the level of the 5th thoracic vertebra. Cardiovascular physiological studies show some of these anatomical variations, especially of the venous system and the ascending aorta, to be modifications for diving. This investigation documents the large blood vessels associated with the heart and related structures in the ringed seal. [source] Macroanatomical Investigation of the Aorticorenal Ganglion in 1-Day-Old Infant SheepANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 3 2009J. Kle, kowska-Nawrot Summary The aorticorenal gland belongs to the paired splanchnic ganglion, which is the main component of the coeliac plexus. It lies near the renal artery and suprarenal gland. The research was conducted on 13 1-day-old infant sheep , eight males and five females. Based on the conducted studies, it was concluded that the aorticorenal ganglion is characterized by the variable location in relation to the abdominal aorta, renal artery, caudal vena cava and suprarenal gland (holotopy), the thoracic and lumbar segment of the vertebral column (skeletotopy) (between L1 and L3) and also a different shape (elongated, round, triangular, oval) as well as variable length (the aorticorenal ganglion is longer on the left side of the body; 2.72 mm) and distance from the caudal end of the suprarenal gland (longer on the left side of the body; 8.34 mm). With regard to the sex of the animal, the ganglion is the longest on the left side in ewes (3.02 mm), while in rams it is the longest on the right side (2.68 mm). Regarding the division according to sex, the longest segment was observed on the right side in ewes (9.27 mm), and the shortest segment in rams was also on the right side (6.84 mm). [source] Origin of the Infrarenal Part of the Caudal Vena cava in the PigANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 5 2008P. Cornillie Summary The vascular topography in the lumbar region of pig embryos and young fetuses was three-dimensionally reconstructed to study some controversial aspects of the origin and development of the infrarenal part of the caudal vena cava. Contrary to general belief, it was found that the supracardinal veins, which form the azygos veins in the thorax, do not take part in the construction of the caudal vena cava in the lumbar region. These veins do appear in the abdomen, but they are only involved in the formation of the lumbar and ascending lumbar veins. The infrarenal part of the caudal vena cava arises from the lumbar part of the right caudal cardinal vein. Whilst this venous pattern is established, the lumbar part of the left caudal cardinal vein disappears and its former location is occupied by large lymphatic connections between the cysterna chyli and the retroperitoneal mesenteric lymphatic sac. On the basis of these findings, a number of hypotheses on the development of anatomical variations of the caudal vena cava should be reconsidered. [source] | ||||||||||