NU 325 Exam 3
PRECORDIUM
Area on the anterior chest overlying the heart/ great vessels, immediately in front of heart
PERICARDIUM
- Tough fibrous, double walled sac that surrounds and protects the heart.
- It has 2 layers that contain a few milliliters of serous pericardial fluid
- Is adherent to the great vessels, esophagus, sternum, and pleura and is anchored to the
diaphragm
Previous
Play
Next
Rewind 10 seconds
Move forward 10 seconds
Unmute
0:00
/
0:15
Full screen
Brainpower
Read More
PERICARDIAL SAC
Contains pericardial fluid that allows smooth friction-free movement of the heart. Surrounds
heart.
MYOCARDIUM
Is the muscular wall of the heart
It does the pumping
ENDOCARDIUM
Is the layer of endothelial tissue that lines the inner surface of the heart chambers and valves.
MEDIASTINUM
,The heart and great vessels are located between the lungs in the middle third of the thoracic
cage (mediastinum).
Where and how the heart sets in the chest cavity. Where is the base and apex?
-Upside down triangle in chest
-Inside the body, the heart is rotated so that its right side is anterior and its left side is mostly
posterior
- Base: top, left sternal border 2nd ICS
- Apex: bottom, points down to the left, 5th ICS mid clavicular
Circulation of the heart
Right Atrium -> Tricuspid Valve -> Right Ventricle -> Pulmonic Valve -> Lungs -> Back into
pulmonary veins -> Left Atrium -> Mitral Valve(bicuspid) -> Left Ventricle -> Aorta -> Body
Know the difference in circulation of a newborn and that of an adult
INFANTS/CHILDREN:
- Fetal heart begin to beat at the end of 3 weeks’ gestation
- Lungs are nonfunctional, but fetal circulation compensates for this
- 02 takes place at the placenta
- Arterial blood is returned to the right side of the fetal heart
- No point in pumping all freshly oxygenated blood to through lungs so its’ rerouted in 2 ways
1. 2/3 of it is shunted through an opening in the atrial septum (foramen ovale) into the left side of
the heart where it is pumped through the aorta
2. The rest of the oxygenated blood is pumped by the right side of the heart out through the
pulmonary artery, but is detoured through the (ductus arteriosus) to the aorta
- Inflation and aeration of the lungs at birth produces circulatory changes -> blood is now
oxygenated through lungs rather than placenta
, - Foramen ovale closes within the first hour because of the new lower pressure in the right side
of the heart than in the left side.
- The ductus arteriosus closes usually within 10 to 15 hours after birth
- Now, left ventricle has the greater workload of pumping into the systemic circulation, so when
the baby has reached 1 year of age, the left ventricle mass increases to reach the adult ratio
2:1, left ventricle to right ventricle.
- The heart’s position in the chest is more horizontal in the infant than in the adult; thus the apex
is higher, located at 4th ICS.
- Reaches adult position when a child reaches 7 years.
Know the difference in circulation of a newborn and that of an adult
ADULT:
- Enters right atrium via vena cava, through Tricuspid Valve, then to the right ventricle, goes
through pulmonary valve and out pulmonary arteries, to the lungs for O2, travels back to the
heart via pulmonary vein, enters left atrium, through bicuspid/mitral valve, then to left ventricle
through aortic valve and out aorta.
Know the valves. Know the structures the valves separate. Know why and when the valves
open and close.
Atrioventricular Valves (AV):
o 2 AV valves separate the atria and ventricles
o Right -> (Tricuspid)
o Left -> Mitral/Bicuspid
o Open during the hearts filling phase (diastole) -> allow ventricles to fill with blood
o During pumping phase (systole) -> AV valves close to prevent regurgitation of blood back into
the atria
Semilunar Valves (SL)
o Set between the ventricles and arteries
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller KINGJAY. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $11.99. You're not tied to anything after your purchase.