Anatomy of circulation I_ part 3.pdf

07/03/24 Anatomy of circulation I: part 3 Learning objective: identify the coronary vessels including the origin and pathways and region of the heart they supply. External surface of the heart: The outer surface of the heart is marked by a number of grooves or sulci. These sulci demonstrate the loca...

07/03/24 Anatomy of circulation I: part 3 Learning objective: identify the coronary vessels including the origin and pathways and region of the heart they supply. External surface of the heart: The outer surface of the heart is marked by a number of grooves or sulci. These sulci demonstrate the location of where the internal partitions bet ween the chambers of the heart are. 1. The coronary sulcus shows the separation of the atrium and ventricle on both sides. This circles the heart. 2. The anterior inter ventricular groove marks the separation of the t wo ventricles. This is located on the sternocostal surface of the heart. 3. The posterior interventricular groove marks the separation of the t wo ventricles. This is located on the diaphragmatic area of the heart. Coronary Arteries: Right Coronary Artery: This originates from the right aortic sinus. Follows the coronary sulcus. It branches off on its course from the right aortic sinus to the posterior inter ventricular sulcus/ groove. It usually supplies: The right atrium and ventricle. Sinu-atrial and atrioventricular nodes. Interventricular septum ( posterior 1/3 ). Left ventricle ( diaphragmatic part only ). 1. Sinu-atrial branch- this supplies the sino-atrial node. 2. Right marginal branch. 3. Posterior inter ventricular branch- this travels in the posterior inter ventricular sulcus. Left Coronary Artery: This originates from the left aortic sinus. Passes bet ween the pulmonary trunk and left auricle. This usually supplies the: Left atrium and ventricle. Right ventricle ( partially ). Interventricular septum ( anterior 2/3 ). AV bundle. Branches of the artery include: Anterior inter ventricular branch- this gives rise to diagonal branches. Circum ex branch- this gives rise to the left marginal branch. Summary of blood supply: Note: the percentages means what proportion of people this applies to. For example, in the nal row the AV node is supplied by the right coronary artery in 80 to 90% of people, but in the other 10% to 20% of people it is supplied by the left coronary artery. Coronary Veins: Ultimately, the venous blood that the cardiac veins are transporting will be returning to the right atrium of the heart. 1. Great cardiac vein- it begins towards the apex of the heart and ascends the anterior interventricular sulcus where it’s related to the anterior inter ventricular artery. Once it reaches the coronary sulcus, this vein turns left and continues onto the posterior aspect of the heart. 2. The coronary sinus – this is an enlargement of the great cardiac vein. This enters the right atrium via an opening. 3. Middle cardiac vein- this can be found in association with the posterior inter ventricular artery. 4. Small cardiac vein- this begins in the coronary sulcus bet ween the right atrium and ventricle. It also drains into the right atrium via the coronary sinus. 5. Right marginal vein- this is a branch of the small cardiac vein. 6. The posterior cardiac vein- this is found on the posterior surface of the left ventricle. it will either drain directly into the great cardiac vein or drain directly into the coronary sinus. 7. Anterior veins of the right ventricle- this drains directly through the wall of the right atrium, as opposed to going through the coronary sinus. Great cardiac vein middle cardiac vein small coronary sinus Right marginal cardiac vein Posterior Anterior cardiac vein vein veins of RA