Heart Anatomy Flashcards
What makes up the right heart border?
R.A and superior vena cava.
What makes up the inferior border?
Right ventricle
Left heart border?
L.V, left pulmonary artery, aortic knuckle and LA appendage
What makes up the superior border?
R + L atrium, superior vena cava, ascending aorta, pulmonary trunk.
What separate the superior and inferior mediastinum?
The mediastinum is the space between the lungs pleura and it is separated into and inferior and superior section by the sternal angle.
Note it is then further divided into an anterior (in front of the pericardium)
Middle (by the heart) and posterior (behind the heart) mediastinum
What is the pericardium?
Thin sac that surrounds the heart - protect, lubricates and helps keep it in place.
Formed of 2 layers with a very small amount of fluid in between. The visceral pericardium is the outer layer of the heart and the sac is made up of fibrous pericardium.
What is a pericardial effusion?
Fluid collected in the pericardium layers. Due to the fibrous pericardium this fluid can not escape. It impairs the filling of the heart (by limiting its ability to expand fully).
The condition is known as cardiac tamponade
What does the pulmonary trunk divide into?
The right and left pulmonary arteries
What does the aorta divide into?
Right and left coronary artery
Brachiocephalic artery
Left common carotid
Left subclavian artery
The brachiocephalic artery then divides into the right common carotid and the right subclavian
What is the fossa ovalis?
It is the foetal bypass of the lungs that closes after birth.
What is the coronary sinus?
It is the main venous drainage of the heart feeding blood back into the right atrium.
What is the job of the Christa terminalis?
Joins to the trabeculated portion of the heart to the the smooth portion (sinus Venosus)
What is the aorta-mitral continuity?
The aortic and mitral valve are joined by the fibrous skeleton of the heart known as…
What are the papillary muscles?
The papillary muscles attach to the two atrioventricular valves and contract during systole to stop the valve inverting.
What are all the grooves of the heart?
Atrioventricular groove
Left ventricular groove or anterior inter ventricular groove.
Posterior inter ventricular groove
What do the coronary arteries divide into?
The left coronary artery divides into the left anterior descending artery and the circumflex
The circumflex further divides into the septal and diagonal and the LAD further divides into obtuse marginal
The right coronary artery divides into the right posterior descending artery and the right marginal artery.
What does the left circumflex artery supply?
The left atrium and left ventricle
What does the right coronary artery supply?
Right atrium and right ventricle and also the inferior left ventricle
What does the LAD artery supply?
The septal and anterior surfaces of the left ventricle and the right ventricle
What does the right marginal artery supply?
Right ventricle and apex of heart
Oxygen saturation of heart muscle is very high and hence it significantly reduces the 02 saturation in the coronary arteries
..
What is the job of the tri-cuspid valve?
Stops the backflow of blood from the right ventricle to right atrium and hence also stops the build up of pressure in the vena cava
Where is the apex of the heart?
The left midclavicular line 5th intercostal space
How many pulmonary veins are there?
There are 2 left and 2 right pulmonary veins.
What makes up the posterior border?
Mainly left ventricle and pulmonary veins
What is the function of pleasurable reflection?
Pleural reflection allows drainage of pericardial fluid from the left of the xiphisternum
What is the role of chordae tendinae?
Papillary muscles (part of ventricle) attach to atrioventricular valves via chordae tendinae
Why can a surgeon perform a heart bypass?
Coronary arteries are epicardial and therefore accessible to the surgeon
Where does the LAD run?
The LAD runs in the anterior interventricular groove
Where does the circumflex run?
In the left atrioventricular groove
Where does the right coronary artery run?
In the right atrioventricular groove
What else does the right coronary artery supply?
The SAN and the AV node
What branches into the posterior descending artery?
Distal RCA branches into posterolateral and posterior descending arteries (latter in about 70% of people)
What is the function of the posterior descending artery?
The posterior descending artery runs in the posterior interventricular groove and supplies inferior septum and LV
What does dominance refer to?
Dominance refers to the artery (RCA or Cx) which supplies the posterior descending artery
Most people (70%) are right dominant – RCA supplies the PDA
About 20% are co-dominant – RCA and Cx both help supply the PDA
About 10% are left dominant – Cx supplies the PDA
