Anatomy Flashcards
What is the mediastinum?
It is the space between both pleural capillaries
What is the superior border of the superior mediastinum?
The oblique plane passing from the jugular notch upward
What is the posterior border of the superior mediastinum?
The superior border of T1
What is the inferior border of the superior mediastinum?
The transverse plane passing from the sternal angle to the intervertebral disc T4-T5
What are the major structures of the superior mediastinum?
The thymus gland, the esophagus, the trachea and the thoracic duct
What vessels are located in the superior mediastinum?
The left/right brachiocephalic veins, the left superior intercostal vein, the superior vena cava, the arch of the aorta and its 3 main branches
What nerves are found in the superior mediastinum?
The phrenic nerves, the vagus nerves and the left recurrent laryngeal branch of the left vagus nerve
What is the most anterior component of the mediastinum?
The Thymus
What is the function of the thymus?
It is involved in the early development of the immune system
What arteries supply the thymus?
The small branches of the internal thoracic arteries
What vein drains the thymus?
The left brachiocephalic vein
What lymph nodes drain the thymus?
The Parasternal and Tracheobroncial Lymph Nodes
What is immediately posterior to the thymus?
The Brachiocephalic Veins
What passes over the left side of the aortic arch?
The Left Suprior Intercostal Vein
What are the rising branches of the arch of the aorta?
The Brachiocephalic Trunk, the Left Common Carotid Artery and the Left Subclavian Artery
What lies between the Pulmonary Artery and the Arch of the Aorta?
The Ligamentum Arteriosum
What is innervated by the Vagus Nerve?
The Esophagus, the Cardiac Plexus and the Pulmonary Plexus
What lies lateral to the Ligamentum Arteriosum?
The Left Recurrent Laryngeal Nerve
Where does the Vagus Nerve originate?
It is the Tenth Cranial Nerve
What does the Phrenic Nerve originate from?
The Anterior Rami of C3-C5
What does the Phrenic Nerve innervate?
The diaphragm, the fibrous pericardium and the parietal layer of the serous pericardium
Where does the right phrenic nerve pierce the diaphragm?
The inferior vena cava opening
Where does the left phrenic nerve pierce the diaphragm?
Near the apex of the heart
What is the major lymphatic vessel in the body?
The Thoracic Duct
Where does the thoracic duct lie?
It passes through the posterior portion of the superior mediastinum
Where is the Anterior Mediastinum?
Posterior to the body of the sternum and anterior to the pericardial sac
What is located in the Middle Mediastinum?
The Pericardium, the Heart, the Origins of the great vessels and various nerves
What defines the boundaries of the middle mediastinum?
The Fibrous Pericardium
What are the layers of the Serous Pericardium?
The Parietal Layer and the Visceral Layer
What innervates the Fibrous Pericardium?
The Phrenic Nerves
What supplies the Fibrous Pericardium?
The Pericardiacophrenic Vessels
Where is the Posterior Mediastinum?
Posterior to the pericardial sac and Diaphragm
Where is the Esophagus located?
In the Posterior Mediastinum
What supplies the esophagus?
The Thoracic aorta, the Branchial arteries and the ascending branches of the left gastric artery
What drains the esophagus?
The Azygous vein, the Hemizygous vein and the oesophageal branches of the left gastric vein in the abdomen
Where is the Heart found?
The pericardial cavity
What is the pericardium innervated by?
The Vagus Nerves, the Phrenic nerves and the Sympathetic trunks
What are the pericardial sinuses?
The Oblique Sinus and the Transverse Pericardial Sinus
What is the posterior part of the heart made of?
The Left Atrium and part of the Right Atrium as well as the proximal part of the great veins
What is the anterior part of the Heart made up of?
The Right Ventricle and part of the Right Atrium and the Left Ventricle
Where does the heart rest in the anatomical position?
The Diaphragmatic surface
What is the diaphragmatic surface made up of?
The Left Ventricle and a small portion of the Right Ventricle
What are the External Sulci?
The Coronary Sulcus and the Anterior/Posterior Interventricular Sulci
What does the Coronary Sulcus contain?
The Right Coronary Artery, the Small Cardiac Vein, the Coronary Sinus and the Circumflex branch of the Left Coronary Artery
What does the Anterior Interventricular Sulci contain?
The Anterior Interventricular Artery and the Great Cardiac Vein
What does the Posterior Interventricular Sulcus contain?
The Posterior Interventricular Artery and the Middle Cardiac Vein
What does the Right Atrium receive blood from?
The Superior Vena Cava, the Inferior Vena Cava and the Coronary Sulcus
What is the function of the Tricuspid Valve?
It prevents backflow of blood into the right atrium
What divides the parts of the right atrium externally?
The Sulcus Terminalis Cordis
What divides the parts of the right atrium internally?
The crista terminalis
What is the space posterior to the crista terminalis?
The sinus of the venae cavae
What is the space anterior to the crista terminalis?
The atrium proper
How are the walls in the sinus of the vanae cavae?
They are smooth and thin
How are the walls in the atrium proper?
They are covered by the pectinate muscles
What is the right auricle?
It is an ear-like conical muscular pouch that externally overlaps the ascending aorta
What separates the atria?
The Interatrial Septum
What is found on the interatrial septum?
The fossa ovalis
What is found on the walls of the right ventricle?
Trabeculae carnae
What muscles are found on the walls of the ventricles?
Papillary muscles
What do the papillary muscles attach to?
Chordae Tendineae
What do the chordae tendineae attach to?
The heart valves
Tricuspid in the right ventricle
Mitral in the left ventricle
What are the papillary muscles of the right ventricle?
The anterior, posterior and septal papillary muscles
What are the cusps of the tricuspid valve?
The anterior, posterior and septal cusps
What is the infundibulum?
It is the outflow tract of the right ventricle
What is the function of the pulmonary valve?
It allows/restricts blood flow into the pulmonary trunk
What are the cusps of the pulmonary valve?
The anterior, right and left semilunar cusps
What does the left atrium receive?
The 4 pulmonary veins
Does the left atrium contain pectinate muscles?
Yes
What can be found on the intertribal septum in the left atrium?
The valve of the foramen ovale
Which compartment of the heart has the thickest layer of myocardium?
The left ventricle
What is the aortic vestibule?
It is the outflow tract of the left ventricle
What are the papillary muscles of the left ventricle?
The anterior and posterior papillary muscles
What are the parts of the interventricular septum?
The muscular and membranous parts
What is the function of the mitral valve?
It prevents back flow of blood into the left atrium
What is the function of the aortic valve?
It allows/restricts blood flow into the aorta
What are the semilunar cusps of the aortic valve?
The right, left and posterior semilunar cusps
What is unique about the cusps of the aortic valve?
They contain the aortic sinuses
What is the function of the aortic sinuses?
They force blood into the coronary arteries
What are the anulus fibrosis?
They form the cardiac skeleton
What connects the annulus fibrosis?
The right and left fibrous trigone
What are the functions of the cardiac skeleton?
- To maintain the stability and diameter of the orifices
- To provide points of attachment for the cusps
- To electrically isolate the atria from the ventricles
What passes through the cardiac skeleton?
The bundle of His
What supplies the cardiac muscles?
The coronary arteries
What drains the cardiac muscles?
The coronary veins
What do the coronary arteries give off?
The marginal and interventricular branches of the coronary arteries
Where do the coronary veins empty?
The coronary sinus
Where does the coronary sinus empty?
The right atrium
What are the branches of the right coronary arteries?
The sinn-atrial nodal branch, the right marginal branch and the posterior interventricular branch
What are the branches of the left coronary artery?
The anterior interventricular branch and the circumflex branch
What are the cardiac veins?
The great cardiac vein, the middle cardiac vein, the small cardiac vein and the posterior cardiac vein
What innervates the heart?
The peripheral nervous system
What is the function of parasympathetic innervation on the heart?
It decreases heart rate and force of contraction and causes vasoconstriction of the coronary arteries
What is the function of the sympathetic nervous system on the heart?
It increases heart rate and force of contraction
What does the parasympathetic innervation of the heart originate as?
The right and left vagus nerve
What does the sympathetic innervation of the heart originate as?
The cardiac nerves of the sympathetic trunk
What are the visceral afferents of the heart?
The cardiac nerves of the sympathetic trunk and the vagal cardiac branch
What part of the heart does the circumflex artery supply?
The anterior part of the left ventricle
