heart Flashcards
What are the 4 corners of the heart?
R upper= 2nd intercostal space
R lower= 4th intercostal space
L upper= 2nd intercostal space
L lower= apex of heart at 5th intercostal space in mid-clavicular line on left
Where is the heart located?
The heart is bounded laterally by? anteriorly by? posteriorly by? inferiorly by? superiorly by?
In the mediastinum
laterally= pleaura
anteriorly= sternum and costal cartilages
posteriorly= Vertebral bodies of thoracic vertebrae
inferiorly= diaphragm
superiorly= Thoracic inlet
What does “the heart is off center, twisted and tilted” mean?
Twisted R (anterior) and L (posterior) chambers; long axis is 45 degrees to long axis of body, to left of midline
List layers of pericardium
Deep- superficial
endocardium, myocardium, visceral pericardium (epicardium), pericardial cavity, parietal layer of serous pericardium, pericardium fibrous layer
what is cardiac tamponade?
What all is it casued by?
is acute compression of heart caused by the heart being stresses by too much pericardial fluid aka periocardial effusion, Pericarditis, viral infection, and autoimmune disease
Unique characteristics of cardiac muscle?
1) Striated, branched fibers
2) Uninucleated
3) Intercalated discs, gap junctions
4) Auto-rhythmicity – contracts on its own
5) Autonomic innervation
What drains the heart?
Corenary sinus drains heart directly into right atrium
Inferior and superior vena cava drain?
Inferior drains anything below the heart; superior drains anything above the heart into the riht atium
What is the auricle and where is it?
It is part of right or left atrium and increases the capacity for blood
Pectinate muscles
are parallel ridges in the walls of the atria of the heart
What is the most anterior chamber of the heart?
right ventricle
What are the folds of muscle on the inside of the ventricle called?
trabecular carnae
What are the muscles called that hold onto the tri and bi valves? how does this work?
papillary muscles in ventricle; contracts to CLOSE and prevent regurgitation of blood back into atrium
what is the mitral valve?
bicuspid
What do the 4 dense connective tissue rings of fibrous skeleton of the heart do?
1) attaches valves
2) prevents overstretching of the valves
3) **acts as electrical insulation between the atria and the ventricles
4) surrounds the valves of the heart which merge together with the interventricular septum