Flashcards in Anatomy questions Deck (23):
Describe anatomy of the radial artery
Commences as one of the two terminal branches of the brachial artery, located medical to the biceps tendon
proximal--between its origin and the distal extent of the antecubital fossa
middle---extends from the antecubital fossa up to the origina of the tendons of brachioradialis, extenso carpi radialis longus and extensor carpi radialis brevis...
distal part-- which runs from the origin of these tendons to the wrist crease
Main nerves at risk during harvesting of radial
Lateral cutaneous nerve of the forearm (C5-C6)--carries sensory fibres to the lateral aspect of the forearm
Superficial radial nerve (nerve roots C7-C8), which crosses the anatomical snuff box and carries sensory fibres to the thenar eminence
Describe the anatomy of the phrenic nerve
Phrenic nerve originates from the C3 C4 and C5 nerve roots and courses down through the neck lying anterior to scalenous anterior
Passes posterior to the subclavian artery and medial to the internal mammary artery to lie on the lateral surface of the pericardium
Right phrenic passes through the inferior vena cava opening in the diaphragm at the level of T8
Left phrenic nerve pierces the muscular part of the left hemi-dirphragm.
How is dominance of the coronary artery system determined
Artery from which the posterior descending artery originates (not the vessel which supplies the greater absolute myocardial mass)
Right dominant system occurs in 80-85%
Left in 10-15%
Co dominant in 5%.
Left dominance more often in males and bicuspid valve
Describe the coronary venous drainage system
Majority of veins drain via the coronary sinus into the right atrium
Coronary sinus is a continuation of the great cardiac vein and the change is denoted by the valve of Vieussens and entry of the oblique vein of the left atrium (the vein of Marshall)
Thesbian veins and larger anterior veins drain directly into the right atrium, bypassing the coronary sinus
Describe location of atrioventricular node
Within the triangle of koch
Boundaries of the triangle of koch include
a) tendon of todaro
b) hinge of the septal leaflet of the tricuspid valve
c) superior margin of the coronary sinus
The membranous septum lies just superior to the triangle of koch and is where the bundle of HIS penetrates to enter the muscular septum.
Describe the structure of the mitral valve
2) Papillary muscles
a) the anterolateral papillary muscle has a single head and takes its blood supply from the circumflex artery
b) the posteromedial papillary muscle has multiple heads and takes its blood supply from the right coronary artery
3) Chordae tendineae:
a) Primary (free edge chordae) which run from the papillary muscles to the free edge of the leaflets
b) secondary (strut chordae) which run from the papillary muscles to the roughened zone of the ventricular surface of the leaflet
c) tertiary (basal chordae) which run from the papillary muscles or ventricular wall to the bases of the leaflets.
Describe the location of the oblique and transverse pericardial sinuses
oblique sinus lies posterior to the left atrium, between the 4 pulmoanry veins and medial to the inferior vena cava
transverse sinus lies behind the aorta and pulmonary trunk and in front of the superior vena cava and left atrial appendage
Describe the course and landmarks of the long saphenous vein
Commences just anterior and superior to the medial malleolus
continues up medical aspect of lower leg before turning slightly posteriorly at the superior aspect of gastrocnemius
passes medial to knee joint (5 cm posterior to the medial aspect of the patella)
Continues up to the medial aspect of the thigh to drain the common femoral vein at the saphenofemoral junction.
The SFJ location 3 cm inferior and 3 cm medial to the femoral artery pulsation.
List veins of the heart
small cardiac vein
middle cardiac vein
Great cardiac vein
Describe infraclavicular approach to exposure to axillary artery
Horizontal skin incision 2 cm below middle 3rd of clavicle.
split pec major fascia and reveal clavipectoral fascia
sharply dissect axillary sheath
divide pec minor as needed but try to avoid it.
artery lies superior and deep to vein--best exposed by mobilizing and retracting vein inferiorly
Thoracoacromial artery may need ligation
obtain proximal and distal control
use a 8 to 10 mm dacron graft and a 3/8 connector
Describe the left phrenic nerve
Between the Left subclavian artery and the Left common carotid artery.
Crosses the arch anterior and to the left of the vagus.
Continues anterior to the root of the lung and passes over the pericardium of the left ventricle and through diaphragm
What does the recurrent nerve supply
All the intrinsic muscles of the larynx except cricothyroid muscle and sensory function below the vocal folds
What is path of Left vagus
Left Vagus starts posterior of the L-CCA and enters the chest between the L-CCA and L-SCA. Gives recurrent laryngeal nerve which goes around the arch (near ligamentum arteriosium) posterior and medical to the CCA.
What are tests of hemolysis
peripheral blood smear--sperocytes
increase indirect Biliubin
increased Hemglobin in urine (Dark--increased hemosiderine, urobiliogen)
bone marrow biopsy
Where is Bundle of HIS
Penetrates central fibrous body to reach the membranous septum to lie on the crest of muscle ventricular septum just beneath the commissure between the right and non-coronary cusps of the aortic valve
What is nodule of arantius
fibrous core at the free edge of the leaflet, usually located centrally.
What is papillary muscle blood supply
posteriormedial--usually has multiple head, most supply from from the RCA only
How much does mitral annulus contract during systole
reduces its cross sectional area by 20-40%
List Chordae of mitral valve
Primary--free edge. Run from the papillary muscle to the free edge of the leaflets
Secondary--strut chordae--run from papillary muscle to the roughened zone on the ventricular surface of each leaflet
tertiary---run from the papillary muscle to ventricular free wall to the base of leaflets
What are leaflets of tricuspid valve
anterior leaflet (largest)
What are two muscles to identify when harvesting the radial artery
Flexor carpi radialis
*often see the flexor pollicis longus