Anatomy Flashcards
the pericardium is made up of what two parts?
- Fibrous pericardium
2. Serous pericardium
describe the four main functions of the pericardium
- fixes the heart - pericardium is attached to the diaphragm, the sternum and the tunica advantitia of the great vessels
- prevents overfilling of the heart
- lubrication - thin layer of fluid between the two layers of serous pericardium reduces friction
- protection from infection
which nerve is responsible for somatic innervation of the pericardium?
the phrenic nerve (C3,4,5)
where is referred pain of the heart often felt?
shoulder pain
what are the 3 layers of the heart wall?
Endocardium - innermost
myocardium - middle layer
epicardium - outermost
what type of epithelium lines the innermost layer of the heart?
simple squamous
How many surfaces does the heart have, what are they called and which chambers do they relate to?
5 surfaces
anterior (sternocostal) - right ventricle
posterior (or base) - left atrium
inferior (or diaphragmatic) - left and right ventricles
right pulmonary - right atrium
left pulmonary - left ventricle
what are the four borders of the heart?
Right border - right atrium
inferior border - left and right ventricle
left boarder - left ventricle (and some or the left atria)
superior border - right and left atrium and the great vessels
what are the sulci of the heart, where do they run, and what are they called?
sulci are grooves on the surface of the heart
there are two main ones:
1. the coronary sulcus (or atrioventricular groove) which runs transversely around the heart - it represents the wall dividing the atria and the ventricles
2. anterior and posterior interventricular sulci - run vertically on their respective sides of the heart - represent the wall separating the ventricles
where do the coronary veins drain into?
directly into the right atrium via the coronary sinus
what are the names of the two section of the right atrium? and what is the structure that separates them?
- sinus venarum - smooth receives blood from superior and inferior vena cava
- atrium proper - includes right auricle and has rough muscular walls
separated by crista terminalis
if foetal circulation what is the structure that allows right to left shunting of blood in the atria? and what does it become after birth?
foramen ovale
becomes the fossa ovalis
name and describe the structure of the 4 valves of the heart
- Tricuspid - RA to RV
- Bicuspid - LA to LV
- Aortic valve - semilunar
- Pulmonary valve - semilunar
what are the two section of the left atrium?
inflow portion - smooth
outflow portion - includes the auricle, rough and lined with muscle
the right and left ventricles can be divided into two sections - name, and describe them
Inflow an outflow
inflow is rough and contains trabeculae carneae
outflow is smooth walled
Describe the conduction of electrical current through the heart
- an excitation signal (action potential) is created by the SA node
- the wave on excitation spreads across the atria, causing them to contract
- Upon reaching the AV node, the signal is delayed
- it is then conducted into the bundle of His, down the interventricular septum
- the bundle of His and Purkinje fibres spread the wave of impulses along the ventricles causing them to contract
indicate the positions of auscultation of the heart valves
Pulmonary - medial end of the second left intercostal space
aortic - medial end of the second right intercostal space
Bicuspid - fifth intercostal space in the midclavicular line
Tricuspid - fourth intercostal space at the left or right sternal angle
