The heart and great vessels Flashcards
What is the base of the heart?
Its posterior surface where it is attached to the great vessels
Where are the surface markings on the right border of the heart?
Right 3rd to 6th costal cartilages
Where are the surface markings on the left border of the heart?
Left 2nd costal cartilage to 5th intercostal space
Where is the auscultation point for the pulmonary valve?
2nd and 3rd left intercostal spaces
Where is the auscultation point for the aortic valve?
2nd right intercostal space radiating up to the neck
Where is the auscultation point for the mitral valve?
Apex, 5th intercostal space, mid-clavicular line
Where is the auscultation point for the tricuspid valve?
Lower left sternal edge, may also be heard on the right
How are the chambers of the heart separated?
The heart is divided longitudinally into right and left halves by a vertical septum lying almost in the coronal plane. Atria are divided from ventricles by the coronary (atrioventricular) groove lying almost in the sagittal plane
What forms the right border of the heart?
The right atrium with its auricle as a triangular, muscular structure pointing to the left
What forms the anterior surface of the heart?
Mostly the right ventricle
What forms the left border of the heart?
Left atrium
What forms the apex of the heart?
Left atrium
Where is the left atrium located within the heart?
At the base of the heart posteriorly but sends its auricle around the left upper aspect of the left ventricle
What proportion of the anterior surface of the heart is formed by the right ventricle?
2 thirds (1 third LV)
What proportion of the inferior (diaphragmatic) surface of the heart is formed by the left ventricle?
2 thirds (1 third RV)
Where do the coronary arteries arise from?
They arise as the first branches of the aorta, from the aortic sinuses above the right and left cusps of the aortic valve
Describe the path taken by the right coronary artery
Arises from the right aortic sinus and passes between the pulmonary trunk and the right auricle.
It runs downwards and backwards in the coronary (atrioventricular) groove
What are the branches from the right coronary artery?
Right marginal
Posterior interventricular
Nodal branches
Where does the right marginal artery run?
Along the inferior border of the heart
What does the posterior interventricular artery supply?
The ventricles and septum
What percentage of the population are right cardiac dominant?
90%
In what proportion of people does the nodal branch from the RIGHT coronary artery supply the SAN?
60%
In what proportion of people does the nodal branch from the LEFT coronary artery supply the SAN?
40%
In what proportion of people does the nodal branch from the RIGHT coronary artery supply the AVN?
90%
In what proportion of people does the nodal branch from the LEFT coronary artery supply the AVN?
10%
Describe the path of the left coronary artery?
Arises from the left aortic sinus and passes between the pulmonary trunk and the left auricle
What are the branches from the left coronary artery?
Anterior interventricular
Circumflex
Nodal branches
Describe the path taken by the anterior interventricular artery
Descends into the anterior interventricular groove, then turning backwards into the posterior interventricular groove
What is another name for the anterior interventricular artery?
Left anterior descending artery
Where does the circumflex artery travel?
Passes around the left edge of the heart in the coronary (atrioventricular) groove between the left atrium and left ventricle