APE 6: The Heart and Central Vasculature Flashcards
What are the functions of the right and left side of the heart?
Right= collecting blood from the body and passing it to the lungs Left= collecting blood from the lungs and passing it through to the body
Which is thicker: ventricles or atria? Why?
Ventricles are thicker because they require blood to be pumped for a greater distance, therefore the blood is at higher pressure. This means the walls need to be thicker to withstand this pressure
What is found at the diaphragmatic, sterno-costal and posterior aspects of the heart?
Diaphragmatic= Left and right ventricles Sterno-costal= Right ventricle Posterior= Left atrium
What are the 4 borders of the heart?
Right, left, superior and inferior
What are the 2 auricles of the atrial wall?
Left and right auricles
Where are the atrioventricular and the interventricular grooves?
Atrioventricular= between atria and ventricles Interventricular= between both ventricles
What is the major vessel arising from the heart and what is at its base?
Aorta, aortic valve at its base
How many cusps does the aortic valve have? What is found above them?
3 cusps, sinuses found above them
Which two sinuses do the coronary arteries arise from?
The anterior and left posterior sinuses
What is the name for the opening of a sinus?
Ostia
What do the atrioventricular grooves contain?
Coronary arteries
What is the origin of the right coronary artery?
Between the right auricle and the root of the pulmonary trunk
Which arteries supply the heart walls?
Coronary arteries
Where does the right coronary artery pass round?
Passes round the diaphragmatic border of the heart and into the posterior interventricular groove
What does the right coronary artery supply?
The AV node
What does the right coronary artery give rise to?
The posterior descending artery
What does the left coronary artery give rise to?
The left anterior descending artery
Which artery is most commonly involved in myocardial infarction?
Left anterior descending artery
What is the aorta the main trunk of?
Systemic arteries
Which way does the arch of aorta curve and then descend?
To the left
At which level does the arch of aorta begin and end?
At the level of the ‘trans-thoracic plane’- T4/5
What are the three branches of the aortic arch?
Brachiocephalic trunk, left common carotid artery, left subclavian artery
What are the two branches of the brachiocephalic trunk?
Right common carotid artery and right subclavian artery
Which vertebral level does the arch terminate at and what does it bifurcate into?
L4, bifurcates into the left and right common iliac arteries
What drains blood from the upper half of the body to the heart’s right atrium?
Superior vena cava
What drains blood from the lower half of the body to the right atrium?
Inferior vena cava
What is the entry point into the heart of the superior vena cava?
When the right and left brachiocephalic veins meet
What is the surface marking of the entry point of the superior vena cava into the heart?
The lower border of the 1st right costal cartilage
Where does the inferior vena cava originate?
At the juction of the right and left common iliac veins
At which vertebral level does the inferior vena cava enter the heart?
T8
What is the position of a normal heart with relation to the vertebral column?
T4-T8
What is the heart contained within?
The pericardium
What are the surface markings of the pericardium?
Diaphragm, phrenic nerves and major vessels superior to the heart
What is cardiac tamponade?
Bleeding into the cardiac sac
How can cardiac tamponade be relieved?
Pericardiocentesis- drainage of fluid in pericardial sac
What is the relevant surface marking of relieving cardiac tamponade?
Manubriosternal joint
What is the name of the outer layer of the pericardium?
Fibrous pericardium
What is the name of the inner layer of the pericardium?
Parietal serous pericardium
What is the name of the layer of the pericardium that is continuous with the heart?
Visceral serous pericardium
What does serous mean and what does it enable?
Serous means that it produces some fluid, allows friction-free movement of the heart inside the sac
What are the pulmonary arteries?
Arteries whereby deoxygenated blood passes from the heart to the lungs
How many pulmonary arteries are there and where do they arise from?
2, arise from the pulmonary trunk
What are the pulmonary veins?
Veins whereby oxygenated blood enters the heart from the lungs
Which nerve innervates the diaphragm and at which vertebral level is this?
Phrenic nerve- C3,4,5
What causes the heart sounds heard through a stethoscope?
The closure of heart valves
Where are sounds from the pulmonary valve best heard?
The 2nd left intercostal space
Which chamber forms the apex of the heart?
Left ventricle
Where is the pulsations of the apex beat typically felt?
In the 5th left intercostal space, in the midclavicular line
Where is the sounds from the mitral valve best heard?
In the 5th left intercostal space, in the midclavicular line
What causes enlargement of the heart?
Heart failure
Where are sounds from the aortic valve best heard?
2nd right intercostal space
What is stenosis and incompetence?
Stenosis= valves becoming stiffer/narrowed Incompetence= valves becoming weakened/leaky
What can stenosis/incompetence lead to? What can be heard/palpated because of this?
Leads to a turbulent flow of blood
Murmur can heard
Thrill can be felt when apex is palpated
What forms the inferior vena cava and at which vertebral level?
Forms by the unuon of the 2 common illiac veins, at L5 level
What are the 3 openings of the right atrium?
Superior and inferior caval and coronary sinus
What are the musculi pectinati
Ridges in the right atrium of the heart
What is the crista terminalis
It is what divides the musculi pectinati
What is the fossa ovalis?
The remnant of the fossa ovale in the foetal heart which allows right to left shunting of blood to bypass the lungs
When does the fossa ovale close?
When the newborn takes its first breath
What is the interatrial spetum?
The solid muscular wall that separates the right and left atrium
Which chamber forms most of the anterior (ventral) surface of the heart?
The right ventricle
What are the two large openings in the walls of the right ventricle?
The right atrioventricular orifice and the orifice of the pulmonary trunk
How many cusps does the right atrioventricular (tricuspid) valve contain?
3
What is the cordae tendinae?
The strong fibrous cords
What are the cordae tendinae attached to?
The cusps of the tricuspid valve and the papillary muscles
Where do the papillary muscles project from?
The ventricular walls
What are the trabeculae carnae?
Irregular bundles and bands of muscles
Where do the trabeculae carnae project from?
The inner surface of the ventricles
What is the infundibulum?
Smooth walled part, lines the right ventricle, leads to the pulmonary trunk
How many pulmonary veins does the left atrium receive?
4 altogether, two from each lung
What does the left ventricle occupy?
A small part of the sterno-costal surface and about 2/3 of the diapragmatic surface of the heart and the apex
What is the orifice leading into the aorta and what is the valve guarding it?
Aortic orifice and semi-lunar valve
What is increased resistance in peripheral vasculature usually caused by and what is the cause of this?
Caused by hypertension
Causes hypertrophy of musculature of the left ventricle
