Cardiovascular Anatomy Flashcards
Mediastinum subdivision
The mediastinum is divided into Superior and Inferior mediastinum and the Inferior mediastinum is subdivided into Ant, Middle and Posterior.
Superior Mediastinum:
Contents
Thymus gland
Brachiocephalic veins
Superior vena cava
Aortic arch and branches:
- R. brachiocephalic trunk
- L. common carotid artery
- L. subclavian artery
Phrenic nerve
Vagus nerve
Left recurent laryngeal nerve
Cardiac nerve plexus
Sympathetic trunk
Trachea
Esophagus
Ductus thoracicus
Prevertebral muscles
Inferior Mediastinum:
Subdivisions
Anterior Inf. Mediastinum
Middle Inf. Mediastinum
Posterior Inf. Mediastinum
Anterior Mediastinum
Fat
Loose connective tissue
Lymph vessels
Anterior borders of lungs & pleura
Internal thoracic blood vessels
Thymus (sometimes)
Middle Mediastinum
Pericardium
Heart
Roots of major blood vessels
Phrenic nerves
Pericardiophrenic blood vessels
POSTERIOR MEDIASTINUM
´
´
Posterior Mediastinum:
Borders
Anterior: Heart and pericardium
Post:T5 – T12
Sup: Sternal angle
Inf: Diaphragm
It has transverse as well as longitudinal structures
Posterior Mediastinum:
Longitudinal Structures
Blood vessels (aorta & azygos system)
Esophagus
Ductus thoracicus
Sympathetic trunk & splanchnic nn. & n. vagus
Posterior Mediastinum:
Tranverse Structures
Post. intercostal blood vessels
Intercostal nerves
Crossing of ductus thoracicus (R to L)
Crossing of v. hemiazygos (L to R)
Pericardium
The pericardium consists of a Fibrous as well as a Serous pericardium
Fibrous pericardium:
Protects heart against sudden overfilling,
Serous pericardium:
-Parietal layer: internal surface of fibrous pericardium
-Visceral layer: surface of the heart = epicardium
Layers of the Pericardium
Junction: Between fibrous pericardium and Adventitia
Fibrous Pericardium
Pericardial Cavity
Serous Pericardium:
- Parietal serous pericardium
- Visceral serous pericardium-Epicardium
Pericardial Sinus
There are two main pericardial Sinuses:
Tranverse Pericardial Sinus
Oblique Pericardial Sinus
Transverse pericardial sinus
Posterior to aorta and pulmonary trunk
Anterior to superior vena cava
Right and left side of pericardial space communicate
and it can be reached from anterior
Oblique pericardial sinus
U-shaped, blind recess posterior to left atrium
pulmonary veins and VCI bulge into pericardial space
Can be reached from inferior
Remnant of mesocardium between transverse- and oblique sinuses
Neurovascular Supply of the Pericardium
Blood supply
Venous drainage
Nerve Innervation
Lymphatic drianage
Blood Supply
Fibrous and parietal serous pericardium: pericardiophrenic arteries, branches of the thorac aorta epicardium: = heart ´ Venous drainage: ´ Nerve supply: ´ Lymphatic drainage:
Venous drainage
Fibrous and parietal serous pericardium:
pericardiophrenic veins, azygos and hemiazygos veins
epicardium: = heart
Nerve Supply
Fibrous and parietal serous pericardium:
n. phrenicus (referred pain), n. vagus (? function), ST (vasomotor)
epicardium: = heart (autonomic)
Lymphatic drainage
Tracheobronchial lymph nodes
Functions of the Fibrous Skeleton
Attachment of valve slips
Prevents dilatation of valves
Attachment of myocardium
Electric insulation
Conducting system of the Heart
Co-ordinate heart cycle and consists of heart muscle fibres and conducting tissue:
SA node: = pacemaker, RA, near superior end of crista terminalis just deep to epicardium, impulses at 70/minute
AV node: interatrial septum, near opening of coronary sinus
AV bundle: split into L & R leg on both sides of IVS
runs deep to endocardium branches: subendocardial = Purkinje fibres
R branch - (RV ant. papillary muscles) / L branch - (LV papillary muscles, IVS)
Septomarginal / moderator band: RV, Between IVS and anterior wall
Control of heart muscle contraction
Conducting tissue, Nerve innervation
Inherent rhythmic ability of myocardium
Blood Supply of the Heart
Endocardium, subendocardial tissue: directly from heart chambers
Myocardium and epicardium: coronary arteries from aortic sinuses (left and right)
Right coronary artery:
- course: in coronary groove to the right
- Branches: R marginal branch, post. interventricular branch, AV nodal artery (85%), SA nodal artery (55%)
-Supply: AV node (80%), AV bundle, SA node (60%), RA, RV, IVS LA (varying amount), LV (varying amount)
Left coronary artery:
-course: between left auricle and pulmonary trunk, in coronary sulcus to the left
Branches: ant interventricular branch - runs in ant interventricular sulcus
- lateral / diagonal artery
- Circumflex artery - runs in coronary sulcus to the L around the heart
- left marginal artery supply: ant. interventricular a.: LV, RV, IVS circumflex a.: LV, LA, IVS, RA (partly), SA / AV node (varies) heart muscles
Venous drainage to the Heart
Primary
Secondary
Primary Drianage
Via coronary sinus
location: coronary sulcus, posterior to the heart orifice: in RA (valve at opening)
Contributing branches:
- Great cardiac vein (» L coronary a.)
- Middle cardiac vein (» post. interventricular a.)
- Small cardiac vein (» R marginal a.)
- Posterior vein of the LV ® inferior surface of LV
- Oblique vein of the LA ® post. wall of the LA
Secondary Drianage
Opens directly in heart chambers
Anterior cardiac veins - between RV and RA
vv. cordis minimae (myocardium)
No valves
Open directly into heart chambers
Collateral circulation of the myocardium
Surface Anatomy of the Heart
Superior Border
Inferior Border
Right Border
Left Border
Superior Border
L 2nd CC (inf. border) (3cm from median)
R 3rd CC (sup. border) (2cm from median)
Inferior Border
R 6th CC
L 5th ICS (med. to mid-clavicular line) = apex
Right Border
R 3rd CC (sup. border)
R 6th CC (2cm from median)
Left Border
L 5th ICS
L 2nd CC
Surface Anatomy for Auscultation of Heart Valves
Aortic valve - 2nd ICS R parasternal
Pulmonary valve - 2nd ICS L parasternal
Mitral valve - 5th ICS mid-clavicular line
Tricuspid valve - 3-6th CC L parasternal
