Heart anatomy Flashcards
Name the three layers of the pericardium
Serous (visceral and parietal) and fibrous
How many millimetres of fluid might be found in the pericardial cavity?
15-50ml
What nerve carries pain signals from the pericardium?
Phrenic nerve
Where does the phrenic nerve originate from?
C3-C5
What ligaments make up the fibrous pericardium?
Sternopericardial, pericardiophrenic and adventitia
What chamber is most anterior?
Right ventricle
What chamber is found on the right pulmonary surface?
Right atrium
What chambers are found on the left pulmonary surface?
Left atrium and left ventricle
What chamber is found at the apex of the heart?
Left ventricle
What chamber is most posterior?
Left atrium
Describe the blood flow in and out of the heart
Deoxygenated blood arrives from the body through the superior and inferior Vena Cava into the right atrium. The blood travels through the tricuspid valve into the right ventricle. It is pumped to the lungs via the pulmonary artery through the pulmonary valve. Oxygenated blood arrives back into the left atrium via the pulmonary vein. Travels through the mitral (bicuspid) valve into the left ventricle. It is pumped out of the aorta through the aortic valve to the body.
What separates the two atria?
Interatrial septum
What separates the two ventricles?
Interventricular septum
What separates the atria from the ventricles?
Atrioventricular septum
What cells make up the pericardium?
Single layer epithelium, called mesothelium
Between what costal cartilages does the heart lie?
2nd-6th cc
What is the function of the serous pericardium?
Contains fluid to minimise friction when the heart beats
Describe the inferior attachment if the fibrous pericardium
pericardiacophrenic ligament to the diaphragm
At the SVC, what happens to the pericardium?
It is continuous with the tunica adventitia
Describe the anterior attachment if the fibrous pericardium
sternopericardial ligament to the sternum
Where does the pericardium attach to the mediastinal pleura?
Laterally
What are the three layers of the pericardium?
Outer fibrous, parietal and visceral
What cranial nerve supplies the visceral pleura?
Vagus (X)
What nerve supplies the two outermost layers of the pericardium?
Phrenic
Branches of what two arteries supplies the pericardium?
Thoracic aorta and internal thoracic artery
Name the two pericardial sinuses
Oblique and transverse
Describe the position of the transverse pericardial sinus
Posterior to the ascending aorta and pulmonary trunk, anterior to the SVC, superior to the left atrium
What chamber dominates the anterior (sternocostal) surface of the heart?
Right ventricle
What heart surfaces would the left ventricle mainly occupy?
posterior-inferior (base-diaphragmatic)
The apex of the heart is formed by which ventricle?
Left ventricle
What anterior surface marker would describe the position of the heart apex?
5th intercostal space, near the mid-clavicular line
What structure lies just posterior to the base of the heart?
Oesophegus
What structures make up the base of the heart?
Left atrium, small part of right atrium, proximal SVC and IVC, pulmonary veins
What chambers make up the inferior border of the heart?
Right ventricle and small part of left ventricle
Which chambers make up the left border of the heart?
Left ventricle and left atria
What is the cardiac skeleton?
Dense, fibrous connective tissue consisting of four rings that electrically isolates the ventricles and the atria.
What is the bicuspid valve’s other name and what does it separate?
Mitral valve, left ventricle from left atrium
Which AV valve has three cusps?
Tricuspid
What structures keep the AV valves closed during ventricular contraction?
Papillary muscles and chordae tendineae
What does the chordae tendineae connect?
Papillary muscles of ventricular wall to the AV valves
What vertebral level would you find the base of the heart?
T5-T8
What is the oblique pericardial sinus?
J shaped zone of reflection, posterior to the left atrium and in between the left and right pulmonary veins.
What is the job of the visceral afferents?
To relay pain and sensory information from the internal organs, glands and blood vessels to the CNS.
What provides the parasympathetic innervation of the heart?
Vagus nerve (X)
Describe the location of the deep cardiac plexus
Posterior to the aortic arch and surrounding the distal trachea and carina.
Describe the location of the superficial cardiac plexus
Anterior-inferior to the aortic arch
What branches of the internal thoracic artery supply the pericardium?
pericardiacophrenic and musculophrenic
The left pulmonary surface faces which lung?
Left lung
Which chamber receives blood from the SVC and IVC?
Right atrium
Describe the position of the right auricle
Anterior (sternocostal) face of the heart, to the upper right of the right atrium, overlapping the root of the ascending aorta.
What is the shallow vertical groove called that extends between the SVC and IVC, and what does it correspond with on the interior face of the right atrium?
Sulcus terminalis, crista terminalis
Where can the SA node be found?
At the top of the sulcus terminalis
Where can the right coronary artery be located?
The right coronary sulcus (or atrioventricular groove)
What runs alongside the right coronary artery?
Small cardiac vein
What is the sinus venarum?
The smooth posterior part of the interior right atrium
What is the atrium proper?
The rough anterior part of the interior right atrium
What separates the two parts of the internal right atrium?
Crista terminalis
What features can be seen on the septal wall of the right atrium?
Fossa ovalis, annulus ovalis, triangle of Koch, coronary sinus, IVC opening, SVC opening, AV orifice, torus aorticus
What is the significance of the fossa ovalis?
It is a oval shaped depression in the septal wall that represents the site of the foramen ovale in developing foetus’
What is continuous with the left end of the valve of the IVC?
Inferior end of annulus ovalis
What is found superior to the triangle of Koch?
Subendocardial ridge
What is found inferior to the triangle of Koch?
opening of the coronary sinus
How can the AV node easily be located?
Found at the apex of the traingle of Koch
What cardiac catheter procedure may the triangle of Koch be useful?
Catheter ablation of the right atrium
What is torus aorticus?
Ridge in the superior portion of the septal wall of the right atrium, created by the ascending aorta sinus.
Does the SVC have any valves?
No
Does the IVC have any valves?
Yes, a non-functioning semi lunar valve
What is the Thesbian valve?
non-functioning valve of the coronary sinus
What are the rings of the cardiac skeleton known as?
Annulus fibrosus
What may cause valve prolapse after MI?
Necrosis of the papillary muscles
What closes the semilunar valves of the aorta and pulmonary trunk?
the recoil of the blood during diastole that is caught in the pouch of the semilunar valve and forces it shut
What is the most common type of valve disease?
Aortic stenosis
Where can the mitral valve be best heard?
5th intercostal space, midclavicular line
Where can the pulmonary valve be best heart?
2nd intercostal space, left sternal edge
Where can the aortic valve best be heard?
2nd intercostal space, right sternal edge
Where can the tricuspid valve best be heard?
4th intercostal space, left sternal edge
The sternal angle corresponds with which costal cartilage?
2nd
The inferior part of the sternal body corresponds with which costal cartilage?
5th
What is responsible for the S1 heart sound?
closure of the AV valves at the beginning of ventricular systole
What is responsible for the S2 heart sound?
closure of the pulmonary and aortic valves at the end of ventricular systole.
What is the S3 heart sound called?
Protodiastolic gallop or ventricular gallop
What is the S4 heart sound called?
Presystolic gallop or atrial gallop
What separates the inflow and outflow portions of the right ventricle?
Supraventricular crest
The inflow portion of the ventricles are covered by what?
trabeculae carnae
What are the three main types of trabeculae carnae?
Ridges, bridges and pillars (papillary muscles)
The outflow portion of the ventricles are smooth: true or false?
True
The left auricle is smooth: true or false?
False, it is continuous with the rough outflow portion of the left atrium
What vessels drain into the left atrium?
Four pulmonary veins
What are the vessels to branch off the ascending aorta?
right and left coronary arteries
When do the coronary arteries receive blood flow, why is this significant?
During ventricular diastole, they are the only arteries to do so.
Which coronary artery is usually bigger?
Left
Where is the right coronary sulcus?
Between the right atrium and ventricle
Which branch of coronary artery supplies the apex of the heart?
Right marginal branch of RCA
Which branch of coronary artery supplies the SA node?
SA nodal branch of RCA
What structures does the RCA supply in a left dominant person (approx 10%)?
Whole right atrium, most right ventricle, small portion of left ventricle and left atrium, SA node and AV node
Where does the left coronary artery divide?
As it enters the left coronary sulcus, the LCx travels in the sulcus and the LAD descends to the apex
Where does the left coronary artery pass through after arising from the ascending aorta?
Between the left auricle and pulmonary trunk
What areas are supplied by the left coronary artery in a left dominant person (approx 10%)?
Most of left atrium and ventricle, a small part of right ventricle, Bundle of His and LBB/RBB
What changes with blood supply to the heart chambers in someone that is right coronary artery dominant (approx 90% population)?
RCA supplies large majority of left ventricle
Where do the coronary lymph vessels drain?
brachiocephalic and tracheobronchial nodes
Describe the location of the SA node
In the superior part of the right atrium, close to the SVC opening
