RESUMO

Background: The left coronary artery (LCA) in the bovines is more developed than the right. Aim: The objective of the study is to describe the bovine coronary system from a morphological point of view, including the morphometry and its distribution. Methods: Arciform suture with 2.0 silk was applied around the sinus orifice and coronary ostium and a number 14 catheter was installed, to perfuse semi-synthetic polyester resin, consisting of a mixture of 85% GP40L palatal with 15% styrene with red color mineral. Results: The average weight of 28 bovine hearts used in our study was 1.534.1 kg. The right coronary artery had a proximal caliber of 5 +/- 0.9 mm. The LCA caliber and length were 9.4 +/- 1.2 and 18.3 +/- 4.8 mm, respectively. This artery was divided into two branches in 85.7% of the cases and trifurcated in 14.3%. The paraconal interventricular branch (PIB) ended more frequently in the apex (46.4%), and its proximal caliber was 6.4 +/- 1.4 mm. The left circumflex branch ended in 82.1% in the subsinusal interventricular sulcus, and its proximal caliber was 5.9 +/- 1.2 mm. The proximal calibers of the PIB and the left circumflex branch did not present statistically significant differences (p = 0.137). The sinoatrial branch presented a dual origin (right and LCA) in 46.4% of the cases and a single origin from the LCA in 53.6% of the samples. In the evaluated hearts, left coronary dominance was observed in most cases (96.4%). Their presence of anastomosis between the branches of the coronary arteries was observed in 57.1% of cases. Conclusion: The presence of a myocardial bridge was found in six hearts (21.4%). In bovines, a high percentage of anastomosis was found, a protective factor in obstruction of the coronary arterial branches.

Assuntos

RESUMO

Mazama gouazoubira is a widely distributed deer in the South American continent. However, studies on its anatomical characteristics are still scarce. The objective of this study was to elucidate the coronary circulation of M. gouazoubira. With this aim, after collecting cadavers on highways, twenty-four hearts injected with latex and preserved in formaldehyde at 10% were dissected. The dissections revealed that all specimens presented left coronary dominance, characterized by the origin of the subsinuous interventricular branch from the circumflex branch of the left coronary artery. The number of ventricular branches originated from branches of the left coronary artery was approximately five times higher than that of the right coronary artery. The occurrence of myocardial bridges was registered in 91.7% of the individuals, with bridges predominating over the paraconal interventricular branch. The mean length of the paraconal interventricular sulcus was significantly higher in males (p = 0.02). The number of atrial branches and ventricular branches, length of myocardial bridges and length of subsinuous interventricular sulcus did not vary significantly between sex. Left coronary dominance and high frequency of myocardial bridges in M. gouazoubira are preponderant anatomical traits also present in different species of Ruminantia suborder. Coronary dominance studies in other South American deer species may confirm the correlation of this trait with the evolutionary history of these animals.

Mazama gouazoubira é um cervídeo com ampla distribuição no continente sul americano. Entretanto, estudos sobre suas características anatômicas, ainda, são escassos. Objetivou-se elucidar a circulação coronariana do M. gouazoubira. Para tal, foram dissecados 24 corações injetados com látex e conservados em formaldeído a 10%, obtidos de cadáveres recolhidos em rodovias. As dissecações revelaram que todos os espécimes apresentaram dominância coronariana esquerda, caracterizada pela origem do ramo interventricular subsinuoso, a partir do ramo circunflexo da artéria coronária esquerda. O número de ramos ventriculares originados, a partir de ramos da artéria coronária esquerda, foi aproximadamente cinco vezes maior do que aquele da artéria coronária direita. A ocorrência de pontes de miocárdio foi registrada em 91,7% dos indivíduos, predominando as pontes sobre o ramo interventricular paraconal. O comprimento médio do sulco interventricular paraconal foi significativa-mente maior em machos (p = 0,02). O número de ramos atriais e ramos ventriculares, comprimento das pontes de miocárdio e comprimento do sulco interventricular subsinuoso, não variaram, significativamente, entre os sexos. A dominância corona-riana esquerda e a elevada frequência de pontes de miocárdio no M. gouazoubira são traços anatômicos preponderantes, tam-bém, em diferentes espécies da subordem Ruminantia. Estudos sobre dominância coronariana em outras espécies de cervídeos sul americanos poderão sugerir a correlação desta característica com a história evolutiva destes animais.

Assuntos

RESUMO

Mazama gouazoubira is a widely distributed deer in the South American continent. However, studies on its anatomical characteristics are still scarce. The objective of this study was to elucidate the coronary circulation of M. gouazoubira. With this aim, after collecting cadavers on highways, twenty-four hearts injected with latex and preserved in formaldehyde at 10% were dissected. The dissections revealed that all specimens presented left coronary dominance, characterized by the origin of the subsinuous interventricular branch from the circumflex branch of the left coronary artery. The number of ventricular branches originated from branches of the left coronary artery was approximately five times higher than that of the right coronary artery. The occurrence of myocardial bridges was registered in 91.7% of the individuals, with bridges predominating over the paraconal interventricular branch. The mean length of the paraconal interventricular sulcus was significantly higher in males (p = 0.02). The number of atrial branches and ventricular branches, length of myocardial bridges and length of subsinuous interventricular sulcus did not vary significantly between sex. Left coronary dominance and high frequency of myocardial bridges in M. gouazoubira are preponderant anatomical traits also present in different species of Ruminantia suborder. Coronary dominance studies in other South American deer species may confirm the correlation of this trait with the evolutionary history of these animals.(AU)

Mazama gouazoubira é um cervídeo com ampla distribuição no continente sul americano. Entretanto, estudos sobre suas características anatômicas, ainda, são escassos. Objetivou-se elucidar a circulação coronariana do M. gouazoubira. Para tal, foram dissecados 24 corações injetados com látex e conservados em formaldeído a 10%, obtidos de cadáveres recolhidos em rodovias. As dissecações revelaram que todos os espécimes apresentaram dominância coronariana esquerda, caracterizada pela origem do ramo interventricular subsinuoso, a partir do ramo circunflexo da artéria coronária esquerda. O número de ramos ventriculares originados, a partir de ramos da artéria coronária esquerda, foi aproximadamente cinco vezes maior do que aquele da artéria coronária direita. A ocorrência de pontes de miocárdio foi registrada em 91,7% dos indivíduos, predominando as pontes sobre o ramo interventricular paraconal. O comprimento médio do sulco interventricular paraconal foi significativa-mente maior em machos (p = 0,02). O número de ramos atriais e ramos ventriculares, comprimento das pontes de miocárdio e comprimento do sulco interventricular subsinuoso, não variaram, significativamente, entre os sexos. A dominância corona-riana esquerda e a elevada frequência de pontes de miocárdio no M. gouazoubira são traços anatômicos preponderantes, tam-bém, em diferentes espécies da subordem Ruminantia. Estudos sobre dominância coronariana em outras espécies de cervídeos sul americanos poderão sugerir a correlação desta característica com a história evolutiva destes animais.(AU)

Assuntos

RESUMO

During the performance of an angiotecnich in a human heart, to highlight the coronary circulation, weobserved the presence of myocardial bridges in the anterior and medial branches of the left coronary artery, inthis heart was also demonstrated the presence of an artery trifurcation left coronary branches that originatedthe anterior interventricular, circumflex and median. Myocardial bridges are intriguing entities that do notalways show signs and symptoms, the presence of the median artery in hearts with myocardial bridges, is oneof the factors that may explain the absence of signs and symptoms in some patients with this entity. Moreoverthe myocardial bridges can explain the signs and symptoms of ischemia on functional testing.

Assuntos

RESUMO

Thirty hearts of female Bos taurus bovines of Canchin breed were studied, the relationship between the arterial wall and the tissues surrounding different drawbridge segments was also assessed. Tissue fragments were collected and treated according to conventional microscopic techniques. Muscle fibers of the pre-bridge and post-bridge segments were of subepicardiac in location. The striate cardiac muscle fibers of the bridging segment are predominantly oblique to the vase, accompanying its longitudinal axis; they separate themselves to form a losanged space to shelter in its center the coronary artery and at its laterals the conjunctive tissue, constituted by colagens and elastic fibers, vases, nerves and adipose tissue

Estudamos em 30 corações de Bos taurus adultos, fêmeas da raça Canchim, as relações entre a parede arterial e o tecido circunjacente nos diferentes segmentos pontinos. Para o estudo microscópico foram coletados fragmentos de material a fresco tratados segundo técnicas microscópicas convencionais. As fibras musculares dos segmentos pré-pontino e pós-pontino são de localização subepicárdica. As fibras musculares estriadas cardíacas do segmento pontino apresentam-se predominantemente oblíquas ao vaso, acompanhando o seu eixo longitudinal; separam-se para formar um espaço losângico que abriga no centro a referida artéria e nas laterais tecido conjuntivo, constituído por fibras colágenas, elásticas, vasos, nervos e tecido adiposo.

RESUMO

It was studied 30 hearts of adult Bos taurus, females of the race Canchim, with the objective of observing the frequency, width, location and angulation of the myocardial bridges. For the macroscopic study the hearts had injected the coronary arteries with solution of Neoprene red-faced latex 450, with posterior fixation in aqueous solution of formol to 10% and after dissection. The results indicate that the myocardial bridges happen in 100% of the hearts, with medium width of 1.24 cm and they locate more commonly in the portions average (38.87%), ventral (26.11%). Multiple bridges are observed in 93.33% of the hearts varying from two to six. The muscular fibers of the segment form angles with the longitudinal axis of the arterial vases with medium of 46º.

Estudaram-se em 30 corações de Bos taurus, fêmeas adultas da raça Canchim, a freqüência, a largura, a localização e a angulação das pontes de miocárdio. Os corações tiveram injetadas as artérias coronárias com solução corada de Neoprene Látex 450, com posterior fixação em solução aquosa de formol a 10% e consecutiva dissecação. Os resultados indicaram que as pontes de miocárdio ocorreram em 100% dos corações, com largura média de 1,24 cm e situaram-se mais comumente nas porções média (38,87%), ventral (26,11%). Pontes múltiplas foram observadas em 93,33% dos corações variando de duas a seis. As fibras musculares do segmento formam ângulos com o eixo longitudinal dos vasos arteriais com mediana de 46º.

RESUMO

Thirty hearts of males cattle from 30 to 50 months old were studied, in order to observe the frequency, width and localization of the myocardial bridges on the coronary arteries. Hearts had their coronary arteries injected with colored solution of Neoprene latex 450, what was followed by dissection. Myocardial bridges were observed in 100% of the hearts.They were multiple in56,6% of the cases. The width of those bridges ranged from 0.3 to 6.2 cm with an avarege of 1.62 cm. Bridges were most frequently found in the medium portion of the ventriculus.The most common site of myocardial bridges was the paraconal interventricular branch.

Estudou-se em 30 corações de bovinos azebuados, machos, com idade variando de 30 a 50 meses, a freqüência, a largura, a posição e a vasculotopia das pontes de miocárdio, mediante injeção das artérias coronárias com solução de Neoprene látex 450 e posterior dissecação. Os resultados indicam freqüência de 100% de corações com pontes e 56,6% das peças apresentaram pontes múltiplas. A largura das pontes variou de 0,3 cm a 6,2 cm com média de 1,62 cm e estas localizaram-se com maior freqüência na região média (36,8%) do ventrículo. O ramo interventricular paraconal foi o que apresentou maior número e freqüência de pontes.