CVR: Anatomy of the Thorax Flashcards
What is the base of the heart?
Superior surface of the heart (formed mainly of the left atrium).
Where is the sternal angle, and at what vertebral level?
Between the manubrium and the sternal body, at level between 4th & 5th thoracic vertebra.
How does the sternal angle divide the mediastinum?
Above sternal angle = superior mediastinum.
Below sternal angle = inferior mediastinum.
What are the three sets of intercostal muscles?
Which are for inspiration/expiration?
External = for inspiration.
Internal & innermost = for expiration.
Which lung has more lobes, the left or right?
The right; 3 lobes. Left only has 2 lobes.
What is the fossa ovalis?
Depressed structure in between right and left atriums, remnant of foramen ovale.
What are the smooth and rough portions of the atria called?
Smooth = sinus venarum
Rough = trabeculated
What is the crista terminalis?
Vertical ridge of myocardium in the right atrium, separates sinus venarum and trabeculated portions of atrium.
Does the left atrium have a crista terminalis?
No, only the right atrium has a crista terminalis.
In the fibrous skeleton of the heart, which valves are connected, and what is this connection called?
Mitral and aortic valves.
The aorto-mitral continuity.
Where does the coronary sinus drain into?
The right atrium.
Where do the coronary arteries lie in the heart?
Under the pericardium, embedded in fat in grooves in between the chambers of the heart.
What arteries does the left mainstem split into?
Left anterior descending (which splits into septal and diagonal arteries)
Circumflex (which becomes obtuse marginal artery)
In coronary arterial dominance, 80-85% of people are right dominant. What does this mean?
The posterior descending artery (PDA) is supplied by the right coronary artery as opposed to circumflex in left-dominance (or both in co-dominance!).
What divides the anterior, middle, and posterior mediastinum?
The pericardium.
How are the atrioventricular valves prevented from everting into the atria during systole?
Papillary muscles (part of the ventricle) are attached to the valves via chordae tendinae.
Which coronary artery runs in the anterior inter-ventricular groove?
Left Anterior Descending.
What part of the heart does the diagonal coronary artery branch supply?
Left ventricle.
Which groove does the circumflex artery run in?
Left atrioventricular groove.
What part of the heart does the obtuse marginal branches supply?
Posterolateral left ventricular wall
Which groove does the right coronary artery run in?
The right atrioventricular groove.
Which groove does the posterior descending artery run in and where does it supply?
Posterior interventrciular groove.
Supplies inferior septum and left ventricle.
The mitral valve is between the left atrium and left ventricle. How many leaflets/cusps does it have?
Two cusps/leaflets.
What is the mediastinum?
The thoracic cavity excluding the lungs (but includes the trachea).
The right coronary artery and the left main stem branch from what major blood vessel?
Ascending aorta/aortic root.
What blood vessels does the brachiocephalic trunk of the aortic arch bifurcate into?
Right common carotid.
Right subclavian
One branch of the aortic arch is the brachiocephalic trunk. Name the other two branches.
Left common carotid.
Left subclavian.
Where does the descending aorta lead to?
The thoracic and then abdominal aorta, supplying blood to lower body.
What fibrous cord-like remanent of the ductus arteriosus connects the pulmonary trunk to the aortic arch?
Ligamentum arteriosum.
What veins converge to form the superior vena cava?
Left and right brachiocephalic veins.
Is the oesophagus anterior or posterior to the trachea?
Posterior.
The phrenic nerve innervates the diaphragm and what other structure?
The pericardium.
What are the ear-like appendages/outpouchings of the walls of the atria called?
Auricles.
In cardiac tamponade, the heart is compressed and unable to fill properly. Which layer of the pericardium is responsible for this and why?
Parietal layer of the pericardium - fibrous and cannot stretch.
What does the recurrent laryngeal nerve originate from?
Vagus nerve - recurrent laryngeal nerve ascends back up the neck to the larynx.
Why might lung cancer cause a hoarse voice?
Cancer at apex of lung may involve the recurrent laryngeal nerves, leading to paralysis of the ipsilateral intrinsic laryngeal muscles, so cannot fully adduct vocal cords.
From what spinal nerves do the phrenic nerves originate from?
C3, C4, C5 (“keep the diaphragm alive”).
What are the three parts of the sternum?
Manubrium, sternal body, xiphoid process/xiphisternum.
What is the name of the joint where the manubrium articulates with the clavicle?
The sternoclavicular joint.
What is another term for the sternal angle, other than the angle of Louis?
Manubriosternal joint.
What does the manubrium articulate with?
Clavicles, first ribs, and the sternal body.
Where is the suprasternal (jugular) notch?
Superior border of the sternum.
With which ribs does the body of the sternum articulate, and what are these joints called?
Ribs 2-7 (the “true” ribs).
Sternocostal joints.
How many pairs of ribs are there and which vertebra do they attach to?
12 pairs, each pair attaching to a thoracic vertebra (of which there are 12!).
What is the costal margin?
The lowest part of the ribs anteriorly.
What is the term for where the ribs articulate with their costal cartilage?
Costochondral joints.
How are ribs 8-10 related?
Their costal cartilage unite and join the 7th costal cartilage
Why are ribs 11 & 12 different to the other ribs?
They are shorter, don’t have costal cartilage and don’t articulate with the sternum, they are “floating” ribs.
Describe how ribs articulate with vertebra at the costovertebral joints.
Tubercle of rib articulates with transverse process, head of rib articulates with vertebral body above and below.
What is the costal groove and what is its function?
Groove in the internal aspect of rib, protects the neurovascular bundle.
What forms the boundary of the superior thoracic aperture?
Manubrium, first ribs, and first thoracic vertebra.
What is a dermatome?
An area of skin innervated by a single spinal nerve.
Are the dermatomes of the thoracic wall in vertical strips or horizontal strips, and which spinal nerves innervate them?
Horizontal strips.
T1-T12
(same as the ribs! just all the thoracic vertebra).
In which dermatome is the umbillicus?
T10
In which dermatome are the nipples?
T4
Where is the axillary tail and what tissue is it part of?
The part of the breast tissue extending towards the anterior axilla.
In breast tissue, what is a lobule composed, and what does it lead to?
Glandular or secretory tissue.
Leading to ducts which converge on the nipple.