Anatomy Of Great Blood Vessels of the thorax- 2024-25.pdf

Anatomy Of Great Blood Vessels Of Thorax By: Dr. ABDELHAMID ELSIFY MBBCH, M.SC. MD ASSOCIATE PROFESSOR OF ANATOMY & EMBRYOLOGY HEAD OF ANATOMY-HISTOLOGY DEPARTMENT  Learning Objectives Knowledge & understanding By the...

Anatomy Of Great Blood Vessels Of Thorax By: Dr. ABDELHAMID ELSIFY MBBCH, M.SC. MD ASSOCIATE PROFESSOR OF ANATOMY & EMBRYOLOGY HEAD OF ANATOMY-HISTOLOGY DEPARTMENT  Learning Objectives Knowledge & understanding By the end of this lecture the student should be able to: Describe the anatomical details with clinical correlates of the following structures: Thoracic aorta Pulmonary trunk Brachiocephalic veins SVC&IVC 8/25/2024 Dr.ABDELHAMID 2 The ascending aorta The ascending aorta: is contained within the pericardial sac which also surrounds the pulmonary trunk in a common sheath. The origin of the ascending aorta is the aortic orifice, at the level of the lower border of the 3rd. left costal cartilage, posterior to the left half of the sternum. Moving superiorly, slightly forward and to the right, the ascending aorta continues to the level of the 2nd. right costal cartilage. At this point, it enters the superior mediastinum and is then referred to as the arch of the aorta. Dr.ABDELHAMID The ascending aorta DR.ABDELHAMID 4 The ascending aorta Immediately above the aortic valve, the ascending aorta presents three small outward bulges opposite the semilunar cusps of the aortic valve. These are the aortic sinuses. Where the right and left coronary arteries originate from the anterior and left posterior aortic sinuses, respectively. Dr.ABDELHAMID Arch of aorta and its branches The arch of the aorta is present in the superior mediastinum. It begins when the ascending aorta emerges from the pericardial sac and courses upward, backward, and to the left as it passes through the superior mediastinum, ending on the left side at the lower border of vertebra T4 The arch is initially anterior and finally on the left side of the trachea. Three branches arise from the superior border of the arch of the aorta; at their origins, all three are crossed anteriorly by the left brachiocephalic vein. Dr.ABDELHAMID Arch of aorta and its branches 8/25/2024 Dr.ABDELHAMID 7 Branches of Arch of aorta 1-Brachiocephalic trunk. It is the largest of the three branches. Above the right sternoclavicular joint, the brachiocephalic trunk divides into: right common carotid artery right subclavian artery. These arteries mainly supply the right 1/2 of the head and neck and the right upper limb, respectively. Dr.ABDELHAMID Branches of Arch of aorta 2- Left common carotid artery. It ascends through the superior mediastinum along the left side of the trachea. It supplies the left 1/2 of the head and neck. 3-Left subclavian artery. It ascends through the superior mediastinum along the left side of the trachea. It supplies the the left upper limb. Thyroid ima artery may arise from brachiocephalic trunk or as a direct branch from arch of aorta. It contributes to the vascular supply of the thyroid gland. Dr.ABDELHAMID Ligamentum arteriosum The ligamentum arteriosum is a short fibrous band which connects the left pulmonary artery with arch of aorta, distal to the origin of the left subclavian artery. It is important in embryonic circulation, when it is a patent vessel (the ductus arteriosus) which allows blood to bypass the lungs during development. The vessel closes soon after birth and forms the ligamentous arteriosum. 1- Anterior relations Superficial cardiac plexus. 2- Posterior relations Left recurrent laryngeal nerve. Dr.ABDELHAMID Descending Thoracic aorta  The descending thoracic aorta begins at the lower border of vertebra T4 , where it is continuous with the arch of aorta.  It ends anterior to the lower border of vertebra T12 , where it passes through the aortic hiatus of the diaphragm.  It lies to the left side of the vertebral column superiorly, it approaches the midline inferiorly, lying directly anterior to the lower thoracic vertebral bodies.  Throughout its course, it gives off a number of branches, which are summarized in Table 3.3. Dr.ABDELHAMID Branches of Descending Thoracic Aorta 8/25/2024 Dr.ABDELHAMID 12 Coarctation of Aorta Clinical picture: Brachial artery pressure is markedly increased and femoral artery pressure is decreased. 8/25/2024 Dr.ABDELHAMID 13 Pulmonary trunk Pulmonary trunk  Course and surface marking: 1. It is about 5 cm long. 2. It begins at the pulmonary orifice of the right ventricle behind the 3rd. Left costal cartilage. 3. It ends in the concavity of the aortic arch behind the 2nd. Left costal cartilage by dividing into right &left pulmonary arteries. 4. Its root presents 3 sinuses just above its valve cusps ( 2 anterior &one posterior) Dr.ABDELHAMID 15 Pulmonary trunk  Relations: Pulmonary trunk lies within the fibrous pericardium in the middle mediastinum. It is enclosed with the ascending aorta in a common tube of serous pericardium - Right relations Right auricle + right coronary artery - Left relations Left auricle + left coronary artery Dr.ABDELHAMID 16 Branches of Pulmonary trunk  Right pulmonary artery: 1. Longer & larger than the left one 2. Runs behind the ascending aorta &SVC  Left pulmonary artery: is connected to the aortic arch by ligamentum arteriosum Dr.ABDELHAMID 17 Brachiocephalic veins  Each brachiocephalic vein is formed by the union of the internal jugular and subclavian veins posterior to the medial end of the corresponding clavicle.  Both unite to form the SVC posterior to the lower border of the 1st right costal cartilage near to the sternum.  Both lie in the superior mediastinum and both have NO valves.  The right brachiocephalic vein: It is short (2.5 cm long ) and has a vertical course. Right relations Right phrenic nerve. Right pleura and lung. Dr.ABDELHAMID 18 Brachiocephalic veins Relations of Left Brachiocephalic vein Tributaries of Brachiocephalic veins Left Brachiocephalic Vein  The left brachiocephalic vein: It is (5 cm long ) and has an oblique course. It runs downwards and to the right behind the upper ½ of manubrium sterni.  Relations: the vein crosses anterior to the 3 big branches of aortic arch Dr.ABDELHAMID 22 Tributaries of Brachiocephalic veins  Common tributaries: 1. Internal jugular vein 2. Subclavian vein 3. Inferior thyroid vein 4. Vertebral vein 5. Internal thoracic vein 6. First posterior intercostal vein  Special tributaries of: left superior intercostal vein to the left one. Note: Right superior intercostal vein drains in the azygos vein. Dr.ABDELHAMID 23 Superior vena cava (SVC)  Superior vena cava is a large venous channel (7 cm long )which collects venous blood from the upper half of the body and drains it into the right atrium.  It is formed by the union of the right and left brachiocephalic veins behind the lower border of the sternal end of the 1st right costal cartilage.  It pierces the pericardium opposite the 2nd right costal cartilage.  It terminates by opening into the upper part of the right atrium behind the 3rd right costal cartilage.  It has no valves. Right relations Right phrenic nerve. Right pleura and lung. Its upper ½ lies in the superior mediastinum and its lower ½ lies in the middle mediastinum within the fibrous pericardium. Dr.ABDELHAMID 24 Tributaries of Superior vena cava (SVC) 1. Right &left brachiocephalic veins 2. The azygos vein arches over the root of the right lung and opens into the back of superior vena cava at the level of the 2nd. right costal cartilage, just before the SVC enters the pericardium. Dr.ABDELHAMID 25 Superior vena cava (SVC) Tributaries of Superior vena cava (SVC) Dr.ABDELHAMID 27 Inferior vena cava (IVC)  The intrathoracic part of IVC is short (0.5 inch long).  Lies in the middle mediastinum within the fibrous pericardium.  It pierces the central tendon of diaphragm opposite T8 one inch to the right side of midline and immediately enters the inferior part of right atrium. Right relations Right phrenic nerve. Right pleura and lung. Dr.ABDELHAMID 28 Inferior vena cava (IVC) Dr.ABDELHAMID 29 Azygos venous system(had been taken in M1)  Case Problem : A 61-year-old man comes to the physician because of a 5-month history of sharp, shooting pain in both legs. Twenty years ago, he had a painless ulcer on his penis that resolved without treatment. He has no history of serious illness. Examination shows small pupils that constrict with accommodation but do not react to light. Sensation to pinprick and light touch is decreased over the distal lower extremities. Patellar reflexes are absent bilaterally. His gait is unsteady and broad-based. This patient is at increased risk for which of the following complications? a) Atrioventricular block b) Mitral valve regurgitation c) Penile squamous cell carcinoma d) Cerebral artery septic embolism e) Inflammatory poly arthritis f) Thoracic aorta aneurysm 8/25/2024 Dr.ABDELHAMID 31 Any Questions?  References: 1- Gray’s Anatomy for students; Richard drake et al; 4th. edition 2-Clinical Anatomy by Regions; by Richard Snell 9th edition. 3-https://www.amboss.com/ Thank You