Coronary arteries of the roe deer (Capreolus capreolus; Linnaeus 1758) heart

A study of the coronary arteries of the roe deer heart was performed on 21 hearts of animals of both sexes and various ages. The roe deer heart is supplied by two arteries: the left coronary artery and the right coronary artery. The left coronary artery arises from the left aortic sinus and forms a short common trunk. The left coronary artery reaches the coronary groove, then divides into the paraconal interventricular branch and the circumflex branch. The circumflex branch gives off several branches to the left ventricle wall and terminates in the subsinuosal interventricular groove as the subsinuosal interventricular branch. The right coronary artery is less pronounced than the left coronary artery. It arises from the right aortic sinus and enters the coronary groove as the right circumflex branch. We found the left arterial cone branch in 75% and the right arterial cone branch in 80% of the cases investigated. The coronary arteries of the heart run subepicardially. In 9 cases we found muscular bridges over the coronary arteries, mostly on the paraconal interventricular branch. In conclusion we affirm the left type of the arterial vascularisation in the roe deer heart.     

Arterial supply to the rat colon

Rats are often used as animal models in studies such as on intestinal transplantation and anastomosis healing, which require colectomy. Although detailed information regarding arterial supply is important to establish accurate and reproducible experimental procedures, this has not been studied in the rat colon. Therefore, we analysed the detailed arterial distribution pattern and its individual variations in the colon of 34 rats. The rat colon received colic branches of the ileocolic artery, and the right, middle and left colic arteries. The single left colic artery constantly arose from the caudal mesenteric artery and was distributed to the descending colon, whereas the others showed variations in number and distribution. The ileocolic artery gave rise to one (12%) or two (88%) colic branches supplying the proximal ascending colon, and these branches formed rich, mesh-like anastomoses along the initial portion of the ascending colon. One (74%) or two (26%) right colic arteries originated from the cranial mesenteric artery and supplied the ascending colon and right colic flexure. Moreover, one (38%), two (56%) or three (6%) middle colic arteries emerged from the cranial mesenteric artery and were distributed to the transverse colon, left colic flexure and proximal descending colon. In total, we categorized the individual variations in arterial branching and anastomosis into 11 patterns. Arterial supply to the rat colon showed a specific pattern and frequent individual variations. These findings thus provide essential information for establishing reproducible models of rat colic surgery.     

Unexpected death in an adult dog with anomalous origin of the left coronary artery from the pulmonary trunk

A two-year-old female miniature poodle died unexpectedly while romping with its owner. Anomalous origin of the left coronary artery from the left pulmonic sinus was discovered at necropsy. Histologically, the right ventricle was unremarkable, but multifocal to coalescing necrosis and fibrosis occurred in the myocardium and endocardium of the left ventricle. Medial hypertrophy of small muscular pulmonary arteries was observed in the lung. The cardiac lesions were similar to those of children with anomalous origin of the left coronary artery from the pulmonary trunk. Pulmonary hypertension, which is suggested by the pulmonary arterial medial hypertrophy, could have increased left ventricular myocardial perfusion and delayed the ischemic myocardial damage that resulted in the death of this dog.     

Reproductive tract vasculature of the female emu (dromaius novaehollandiae)

The arterial supply of the ovary and oviduct is provided by the ovarian artery, cranial oviductal artery, accessory cranial oviductal artery, middle oviductal artery, caudal oviductal artery and the medial and lateral vaginal arteries. These arteries supply various regions of the oviduct and are branches of either the left cranial renal artery, left external iliac artery, left middle renal artery, left lateral caudal artery or the left pudendal artery. The veins that drain the reproductive tract are satellite vessels to each artery that supplied the tract.     

The right coronary artery is absent in the chinchilla (Chinchilla lanigera)

A total of 10 adult, healthy, male chinchillas (Chinchilla lanigera) were used to investigate the origin, course, and termination of the coronary arteries. Coloured latex was injected into the carotid arteries following conventional anatomical applications. In all the chinchillas examined, the left coronary artery was the single coronary artery. The right coronary artery was missing. Additionally, a small vessel originating from the cranial border of the aorta was observed in one chinchilla. The left coronary artery divided into the paraconal, interventricular and left circumflex rami. The left marginis ventricular ramus arose from the paraconal interventricular ramus in eight chinchillas, and from the left circumflex ramus in two. The ventricular and septal branches of the left coronary artery ran subepicardially at the beginning mostly parallel to the muscle fibres, also surrounded by a thin adipose tissue. It was concluded that the only left coroner artery supplied blood to the heart in the chinchilla.     

Hemodynamic effects of nitrous oxide in isoflurane-anesthetized cats

OBJECTIVE: To determine the hemodynamic effects of nitrous oxide in isoflurane-anesthetized cats. ANIMALS: 12 healthy adult domestic shorthair cats. PROCEDURE: Cats were anesthetized by administration of isoflurane in oxygen. After instruments were inserted, end-tidal isoflurane concentration was set at 1.25 times the individual minimum alveolar concentration, and nitrous oxide was administered in a Latin-square design at 0, 30, 50, and 70%. Each concentration was administered for 25 minutes before measurements were obtained to allow for stabilization. Heart rate; systemic and pulmonary arterial pressures; central venous pressure; pulmonary artery occlusion pressure; cardiac output; body temperature; arterial and mixed-venous pH, PCO2, PO2, and hemoglobin concentrations; PCV; and total protein and lactate concentrations were measured before and during noxious stimulation for each nitrous oxide concentration. Arterial and mixed-venous bicarbonate concentrations and oxygen saturation, cardiac index, stroke index, rate-pressure product, systemic and pulmonary vascular resistance indices, left and right ventricular stroke work indices, arterial and mixed-venous oxygen contents, oxygen delivery, oxygen consumption, oxygen extraction ratio, alveolar-to-arterial oxygen difference, and venous admixture were calculated. RESULTS: Arterial pressure, central venous pressure, pulmonary arterial pressure, rate-pressure product, systemic and pulmonary vascular resistance indices, arterial PCO2, and PCV increased during administration of 70% nitrous oxide. Arterial and mixed-venous pH, mixed-venous PO2, and alveolar-to-arterial oxygen difference decreased during administration of 70% nitrous oxide. Results before and during noxious stimulation were similar. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of 70% nitrous oxide to isoflurane-anesthetized cats resulted in improved arterial pressure, which was related to a vasoconstrictive effect.     

Arterial Vascularization and Morphological Characteristics of Adrenal Glands in the Pampas Deer (Ozotoceros bezoarticus,Linnaeus 1758)

This research presents morphological characteristics of adrenal glands and a demonstration of arterial vascularization in the Pampas deer, which is considered to be in extreme danger of extinction. A total of ten deer constituted the material of the study. Vascularization of organs was investigated by using latex injection technique. Left adrenal glands were basically supplied by coeliac, cranial mesenteric, renal and lumbal arteries. The arterial vascularization of the left adrenal glands was very complex in comparison with right adrenal glands. In two examples, branch of the lumbal artery was divided into phrenic caudal artery and cranial adrenal artery. In six examples, it was observed that the caudomedial and ventral regions of the left adrenal glands were also supplied by thinner branches that stemmed from second left lumbal artery. Besides, coeliac and cranial mesenteric arteries also gave off shorter branches supplying the cranial region of the left adrenal glands in five examples. It was determined that two branches originated from abdominal aorta directly for supplying left adrenal glands in only two examples. In four examples, two caudal adrenal arteries stemmed separately from left renal artery in a short distance. Arterial vascularization of right adrenal glands was more constant and supplied by lumbal and renal arteries. The adrenal glands were generally oval or round shaped. In only two examples, left adrenal glands were ‘V‐’ or heart‐shaped. There was no significant difference (P > 0.05) in sizes between right and left adrenal glands.     

Arterial and venous supply to the bovine jejunum and proximal part of the ileum

The blood vasculature of the bovine jejunum and proximal part of the ileum was studied in 20 mature dairy cows at slaughter. The cranial mesenteric artery and vein supplied the jejunum and ileum, and their major branches were present in all specimens and supplied similar regions of the intestinal tract. Proximal branches of the cranial mesenteric artery were pancreatic arteries, caudal pancreaticoduodenal artery, middle colic artery, and ileocolic artery. A large collateral branch arose from the proximal segment of the cranial mesenteric artery, anastomosing with the continuation of the cranial mesenteric artery distally along the jejunum. Jejunal arteries arose from the continuation of the cranial mesenteric artery, forming a series of anastomosing arches. Straight vessels arising from these arches did not branch or anastomose before entering the serosal layer of the intestine. The proximal part of the ileum was supplied by branches from the continuation of the cranial mesenteric artery; these branches anastomosed with the mesenteric ileal (ilei mesenterialis) artery, a branch of the ileocolic artery. The venous supply paralleled the arterial supply in all specimens.     

The arterial supply of Meckel's diverticulum in geese (Anser anser domesticus).

This study was carried out to describe the arterial supply of Meckel's diverticulum (MD) in geese, using 36 adult healthy geese of both sexes, 50 to 52 weeks of age. The arterial supply of MD was classified into three types, In the first type, MD was supplied by a very distinct branch from the cranial mesenteric artery in 21 geese. In the second type, it was supplied by one terminal branch from the cranial mesenteric artery in 9 geese. In the third type, it was supplied both by one branch from the jejunal artery and by terminal branch from the cranial mesenteric artery in 6 geese. Based on the these types, we found significant differences (p < or = 0.01) in the length of MD between type I and II. The blood supply of the third type was observed more frequently in the male than in the female. Results from this study may contribute to the anatomical knowledge of arterial supply of MD in the geese.     

Effects of gastric distention-volvulus on coronary blood flow and myocardial oxygen consumption in the dog

Gastric distention-volvulus (GDV; at 50 mm of Hg gastric inflation pressure) was experimentally induced in 8 dogs anesthetized using pentobarbital. Hemodynamic indices including heart rate, mean arterial pressure, cardiac output, and coronary blood flow (4 dogs) were measured during a 20-minute period of GDV and for 10 minutes after decompression. Arterial and coronary venous oxygen tensions were also measured for calculation of myocardial oxygen extraction (7 dogs) and myocardial oxygen consumption (4 dogs). Dogs were monitored for 72 hours postoperatively for the occurrence of arrhythmias, then were euthanatized for gross and histologic examination of the heart. Experimental GDV resulted in significant (P less than 0.05) decreases in cardiac output (89%), mean arterial pressure (45%), and coronary blood flow (50%) compared with control values. Myocardial oxygen extraction increased (30%) and overall myocardial oxygen consumption decreased (50%), compared with control values. Evidence of subendocardial necrosis was seen in 6 dogs, 4 of which had developed ventricular arrhythmias 8 to 24 hours postoperatively.     

Study of lobation and vascularization of the lungs of wild boar (Sus scrofa)

The purpose of this study was to describe the anatomy of the lungs of wild boars for comparison with those of domestic swine. It was found that the right lung of the wild boar is divided into four lobes: cranial, median, caudal and accessory, whereas the left lung is divided into two lobes: cranial and caudal. In 93.4% of the cases, right pulmonary artery separates into the ascendant, descendant, median, accessory and caudal branches. In 73.3% of the cases, left pulmonary artery separates most frequently to form three branches to the cranial lobe, whereas the median lobe is generally supplied by only one arterial branch. There is a single pattern of bronchial distribution: in the right lung a tracheal bronchus leads to the cranial lobe, where it separates into the cranial and caudal bronchi and there are also bronchi to the median, caudal and accessory lobes. In the left lung, the large bronchus separates to form two branches, one of which further separates to form two branches to the cranial lobe whereas the other forms a single branch to the caudal lobe.     

Gross anatomy of the portal vein and hepatic artery ramifications in dogs: corrosion cast study

The anatomical variations of the portal vein and the hepatic artery ramifications were analysed on liver corrosion casts in 20 dogs as a possible aid in the surgical management of the organ. The portal vein ramified similarly in all dogs. It divided into the smaller right portal branch from which vessels for the caudate process and both right lobes arose and the substantial left portal branch, which supplied the remaining liver portions and in 12 cases also the dorsal part of the right lateral lobe. Right lateral, right medial and left branches are the major arteries originating from the hepatic artery; however, their origin and course varied among individual animals. In 10 livers, the right lateral and the left branches originated from the hepatic artery, while the right medial branch arose from the left branch and usually supplied the right medial lobe solely. In nine livers, the right medial branch arose directly from the hepatic artery and supplied quadrate lobe and gallbladder as well, while in one liver the common artery, which subsequently divided into lobar branches, branched away from the hepatic artery. An additional branch for the caudate process, originating directly from the hepatic artery, was observed in 10 livers. Certain liver portions received the arterial blood from two major branches, which was particularly characteristic for the right medial lobe (six livers) and caudate process (10 livers). The course of the major arterial branches was also variable, although they proceeded in close anatomical relationship with the portal vein branches. The left arterial branch accompanied the left portal branch on its dorsal aspect (15 cases) or crossed it from the caudal aspect (five cases). The right lateral branch crossed the initial parts of the left and right portal branches either from cranial (12 cases) or caudal aspects (eight cases), while the right medial branch always crossed the left portal branch from its caudal aspect.     

Arterial Vascularization of the Gastrointestinal Tract of the Pampas Deer (Ozotoceros bezoarticus,Linnaeus, 1758)

Based on gross dissection of fifteen adult animals (11 females, 4 males), we described the arterial supply of the stomach and intestines of the pampas deer (Ozotoceros bezoarticus), a South American endangered species. The coeliac artery emitted the splenic, left gastric and hepatic arteries. The splenic artery directed towards the spleen, and the right ruminal artery, which is its only collateral directed towards the stomach, being the main artery of the rumen. The left gastric artery gave origin to the left ruminal, the reticular and the left gastroepiploic arteries. The left gastroepiploic artery originated the reticular accessory artery. Both arteries, gastric and left gastroepiploic, anastomosed their right counterparts derived from the hepatic artery on the curvatures of the abomasum. The cranial mesenteric artery irrigated the second half of the duodenum until the beginning of the descending colon. The thickest branch emitted by the cranial mesenteric artery was the ileocolic artery, which was destined to the ascending colon, caecum and ileum. The colic branches and the right colic arteries were irradiated on the right surface of the spiral loop of the ascending colon and distributed to both centripetal and centrifugal coils of the ascending colon; the colic branches were also anastomosed with the last jejunals and ileals and with the right colic arteries. There were no variations in the origin of any of the main branches derived from the coeliac and cranial mesenteric arteries. This species had a basic pattern of arterial distribution similar to small domestic ruminants.     

Vascular Anatomy of the Descending Colon of the Horse

The blood supply to the descending colon of the horse was studied by gross dissection and methyl methacrylate corrosion casts. The arterial supply is derived from the left colic artery and cranial rectal artery with the left colic artery supplying approximately the proximal three fourths. Each artery gives off four to eight arcuate arteries that form a series of anastomosing arcades. The arcade pattern continues to form a marginal artery that parallels the long axis of the colon. Small branches from the marginal artery anastomose with adjacent branches to form a secondary arcade. The secondary arcade lies approximately 1 cm proximal to the mesenteric teniae and sends off long arteries at regular intervals that course circumferentially around the bowel. The long arteries begin under the serosal mesothelium and perforate the muscular layers to course in the submucosal layer. The long arteries branch off supplying the wall of the colon and arborize over the antimesenteric surface, anastomosing with the vessels from the opposite side. The result is the formation of a series of vascular rings surrounding the colon. Venous return, in general, parallels the arterial supply.     

Xylazine and xylazine-ketamine in dogs

The cardiopulmonary consequences of IV administered xylazine (1.0 mg/kg) followed by ketamine (10 mg/kg) were evaluated in 12 dogs. Xylazine caused significant decreases in heart rate, cardiac output, left ventricular work, breathing rate, minute ventilation, physiologic dead space, oxygen transport, mixed venous partial pressure of oxygen, and oxygen concentration. It caused significant increases in systemic blood pressure, central venous pressure, systemic vascular resistance, tidal volume, and oxygen utilization ratio. The subsequent administration of ketamine was associated with significant increases in heart rate (transient increase), cardiac output, the alveolar-arterial PO2 gradient and venous admixture (transient increase), and arterial PCO2 (transient increase). It caused significant decreases in stroke volume (transient decrease), left ventricular stroke work (transient decrease), effective alveolar ventilation, arterial PO2 and oxygen content (transient decrease).     

The effect of moderate hypovolemia on cardiopulmonary function in dogs

Objective: To collate canine cardiopulmonary measurements from previously published and unpublished studies in instrumented, unsedated, normovolemic and moderately hypovolemic dogs. Design: Collation of data obtained from original investigations in our research laboratory. Setting: Research laboratory, School of Veterinary Medicine. Subjects: Sixty‐eight dogs. Interventions: Subjects were percutaneously instrumented with an arterial catheter and a thermodilution cardiac output catheter. A femoral artery catheter was percutaneously placed for blood removal. Measurements and main results: Body weight, arterial and mixed‐venous pH and blood gases, arterial, pulmonary arterial, pulmonary artery occlusion, and central venous blood pressure, cardiac output, and core body temperature were measured. Body surface area, bicarbonate concentration, standard base excess, cardiac index (CI), stroke volume, systemic and pulmonary vascular resistance, left and right ventricular work and stroke work indices, left and right rate‐pressure product, alveolar PO₂, alveolar–arterial PO₂ gradient, arterial and mixed‐venous and pulmonary capillary oxygen content, oxygen delivery, oxygen consumption, oxygen extraction, venous admixture, arterial and venous blood carbon dioxide content, arterial–venous carbon dioxide gradient, carbon dioxide production were calculated. In 68 dogs, hypovolemia sufficient to decrease mean arterial blood pressure (ABPm) to an average of 62 mmHg, was associated with the following changes: arterial partial pressure of carbon dioxide (PaCO₂) decreased from 40.0 to 32.9 mmHg; arterial base deficit (BDa) increased from ?2.2 to ?6.3 mEq/L; lactate increased from 0.85 to 10.7 mm /L, and arterial pH (pHa) did not change. Arterial partial pressure of oxygen (PaO₂) increased from 100.5 to 108.3 mmHg while mixed‐venous PO₂ (PmvO₂) decreased from 49.1 to 34.1 mmHg. Arterial and mixed‐venous oxygen content (CaO₂ and CmvO₂) decreased from 17.5 to 16.5 and 13.8 to 9.6 mL/dL, respectively. The alveolar–arterial PO₂ gradient (A‐a PO₂) increased from 5.5 to 8.9 mmHg while venous admixture decreased from 2.9% to 1.4%. The ABPm decreased from 100 to 62 mmHg; pulmonary arterial pressure (PAPm) decreased from 13.6 to 6.4 mmHg; and pulmonary arterial occlusion pressure (PAOP) decreased from 4.9 to 0.1 mmHg. CI decreased from 4.31 to 2.02 L/min/m². Systemic and pulmonary vascular resistance (SVRI and PVRI) increased from 1962 to 2753 and 189 to 269 dyn s/cm⁵, respectively. Oxygen delivery (DO₂) decreased from 787 to 340 mL/min/m² while oxygen consumption (VO₂) decreased from 172 to 141 mL/min/m². Oxygen extraction increased from 20.9% to 42.3%. Conclusions: Moderate hypovolemia caused CI and oxygen delivery to decrease to 47% and 42% of baseline. Oxygen extraction, however, doubled and, therefore, oxygen consumption decreased only to 82% of baseline.     

Hemodynamic effects of sevoflurane in cats

OBJECTIVE: To determine hemodynamic effects of 3 concentrations of sevoflurane in cats. ANIMALS: 6 cats. PROCEDURE: Cats were anesthetized with sevoflurane in oxygen. After instruments were inserted, end-tidal sevoflurane concentration was set at 1.25, 1.5, or 1.75 times the individual minimum alveolar concentration (MAC), which was determined in another study. Twenty-five minutes were allowed after each change of concentration. Heart rate; systemic and pulmonary arterial pressures; central venous pressure; pulmonary artery occlusion pressure; cardiac output; body temperature; arterial and mixed-venous pH, PCO2, PO2, oxygen saturation, and hemoglobin concentrations; PCV; and total protein and lactate concentrations were measured for each sevoflurane concentration before and during noxious stimulation. Arterial and mixed-venous bicarbonate concentrations, cardiac index, stroke index, rate-pressure product, systemic and pulmonary vascular resistance indices, left and right ventricular stroke work indices, PaO2, mixed-venous partial pressure of oxygen (PVO2), oxygen delivery, oxygen consumption, oxygen-extraction ratio, alveolar-to-arterial oxygen difference, and venous admixture were calculated. Spontaneous and mechanical ventilations were studied during separate experiments. RESULTS: Mode of ventilation did not significantly influence any of the variables examined. Therefore, data from both ventilation modes were pooled for analysis. Mean arterial pressure, cardiac index, stroke index, rate-pressure product, left ventricular stroke work index, arterial and mixed-venous pH, PaO2, and oxygen delivery decreased, whereas PaCO2, PVO2, and mixed-venous partial pressure of CO2 increased significantly with increasing doses of sevoflurane. Noxious stimulation caused a significant increase in most cardiovascular variables. CONCLUSIONS AND CLINICAL RELEVANCE: Sevoflurane induces dose-dependent cardiovascular depression in cats that is mainly attributable to myocardial depression.     

Antiarrhythmic effects of diazepam during coronary artery occlusion in dogs.

The ventral interventricular branch of the left coronary artery was ligated in a 2-step operation in 10 dogs whose electrocardiograms and systemic arterial blood pressures were then monitored during the next 7 days. Monitoring was done in awake dogs given 1 mg of diazepam per kilogram of body weight (intravenously administered in 3 dogs and orally in 7). Because ventricualr ectopic activity was greatest during the interval of 10 to 48 hours after ligation, the antiarrhythmic activity of diazepam was recorded during this 38-hour interval. After administration of diazepam by either route, frequency of ventricular ectopic beats decreased from 98 to 80%. THIS REDUCTION BETAN IMMEDIATELY AFTER THE INTRAVENOUS ADMINISTRATION AND PERSISTED FOR ONLY 5 MINUTES; REDUCTION BEGAN APPROXIMATELY 1 HOUR AFTER THE ORAL ADMINISTRATION AND PERSISTED 4 TO 6 HOURS. Systemic arterial blood pressure decreased only after the intravenous administration. It is concluded that diazepam is effective in reducing the frequency of ventricular ectopic activity after occlusion of major branches of coronary arteries, that diazepam works independent of alterations in systemic arterial blood pressure, and that orally administered diazepam prolongs antiarrhythmic activity. Possibly, the adjuvants present in the parenteral form of diazepam reduce antiarrhythmic activity by being, themselves, arrhythmogenic.     

Vascular anatomy of the equine small colon

The vasculature of 22 small colons from dead adult ponies was perfused with latex or barium sulphate solution. The vascular anatomy was studied by use of dissection and alkali digestion of the latex specimens and microangiography of the barium sulphate-perfused specimens. The small colon is supplied by the caudal mesenteric artery. The left colic artery arises from the caudal mesenteric artery, which then becomes the cranial rectal artery. Branches from the left colic and cranial rectal arteries form anastomosing arcades that become narrower distally along the length of the small colon. From these arcades arise terminal arteries, which enter the small colon wall and give rise to a subserosal, an intermuscular, and a large submucosal plexus, with frequent anastomoses between them. The venous drainage closely parallels the arterial supply, except near to its origin from the portal vein, when the left colic vein and caudal mesenteric vein are separate from the corresponding arteries.     

兰州大尾羊心脏冠状循环血管宏观解剖观察

选取五个不同年龄和性别的兰州大尾羊的心脏,分别采用20%的ABS丙酮溶液进行血管灌注,以红色染料的溶液灌注动脉而用蓝色染料的液体来灌注静脉。结果表明,兰州大尾羊的动脉血液是由起源于主动脉的左冠状动脉和右冠状动脉供应的,左冠状动脉比较粗大。