Anatomy Lecture 2: Heart Flashcards
Middle Mediastrium Boundries:
- Superiorly
- Inferiorly
- Laterally on the left
- Laterally on the right
Middle Mediastinum Boundries:
-Superiorly: sternal angle, T4/T5
Inferiorly: xiphisternum/T9
Laterally on the left: 5th intercostal space in midaxillary line
Laterally on the right: along the sternal border
There is a superior, inferior (anterior, posterior, and middle) mediastinum
Within which part does the heart lie?
The heart lies in the middle mediastinum
What is the pericardium?
Describe the parietal and visceral layers
The pericardium is a closed sac containing fluid for lubrication. It surrounds the heart
The visceral layer (epicardium) is a serous epithelium that is closely applied to the heart.
The parietal layer comprises two layers: serous epithelium thta is continous with visceral layer and a thick fibrous layer that is continous with the adventitia of the great vessels entering and leaving the heart.
Transverse and oblique Sinus:
There are two sinuses formed as the result of reflections of the pericardium where the visceral and parietal layers are continous with one another at the great vessels.
The transverse sinus lies above the entry of the ____
The oblique sinus lies between ____
Explain their locations in more detail
Transverse sinus lies above the entry of the pulmonary veins.
The transverse sinus is between the ascending aorta and and pulmonary trunk in front, and the superior vena cava, left atrium and pulmonary veins behind.
The oblique lies below the pericardial reflection in between the pulmonary veins.
The oblique sinus is between the left atrium in front and the fibrous pericardium behind.
Circulation of the Blood Through the Heart:
- Blood enters the right atrium through the _____
- Blood then leaves the right atrium through the ______ valve into the right ventricle
- Exits the right ventricle through the ______ to the _______
- Returns from the lungs to the left atria via the ______
- Passes the _______ into the left ventricle
- Exits the LV via the ______ into the _____
Blood enters the right atrium via the superior and inferior vena cava
Then passes through the tricuspid valve into the RV
Exits the RV via the pulmonary semilunar valve into the pulmonary trunk (pulmonary artery)
Returns from the lungs into the left atria via the pulmonary veins
Passes through the bicuspid/mitral valve into the LV
Exits by passes through the aortic semilunar valve into the ascending aorta
Label the following blacked out items
Explain them in further detail too
- Pectinate muscles: rough/meaty in both atria
- Cristae Terminalis: ridge houses the SA node
- Fossa ovalis: embryological shunt open in utero to bypass the lungs
- Coronary sinus: 90% of all veins dump into the coronary sinus which feeds back into the RA
The _______ is a smooth ridge seperating 2 embryological regions and gives rise to the origin of the pectinante muscles. (within the RA)
On the outside of the heart lies a groove called the _________
The cristae terminalus is a smooth ridge seperating two embryological regions and gives rise to the origin of the pectinate muscles (in the RA)
On the outside of the heart lies a groove called the sulcus terminalus
_________ tense and prevent prolapse of valves going into the ventricles
Papillary muscles tense and prevent prolapse of valves
Papillary muscles are connected to valves via chordinae tendinae
What does the moderator band do?
The moderator band (in the right ventricle) assists in carrying impulses to the papillary muscles milliseconds before the ventricle contracts.
This causes papillary muscles to tense and help prevent prolapse of the tricuspid valve
An open fossa ovalis can cause mixing of good and bad blood, known as _______
An open fossa can cause mixing of good and bad blood known as Atrial Septal Defect (ASD)
Label the following things on the Right Ventricle
- Tricuspid Valve
- Chordae tendinae
- Papillary Muscles
- Moderator band
- Trabecuale Carnae
Label the following things on the Left Atrium
- Openings of the pulmonary veins
- Pectinate Muscles
- Fossa Ovalis
Which wall within the heart is the thickest?
Left ventricle is the thickest wall
Remember, it pumps blood through the aorta and into the entire body (high pressure system)
Both the left and right coronary arteries come off the ______
Both the left and right coronary arteries are supplied by the aorta
What branches off the left coronary artery vs the right coronary artery?
Anterior off of ____
Posterior off of ____
Left Coronary Artery has an LAD and a circumflex
Right coronary artery has a marginal branch and a posterior portion
Anterior off of left coronary artery
Posterior off of right coronary artery
Innervation of the heart:
______ slows it down
_______ speeds it up
Vagus nerve (X) slows it down and uses ACh as its NT
Note: atropine blocks ach, and therefore speeds up the heart
SNS speeds it up by dumping NE on the heart
the SNS to the heart is blocked by beta blockers
Explain the PROJECTIONS of the heart valves
Projections: PAM T
Explain the AUSCULTATIONS of the heart valves
APTM
All Physicians Take Money
