Circulatory system Flashcards
Where is the mediastinum
space bounded anteriorly by sternum and costal cartilage
What are the divisions of the mediastinum
- superior mediastinum
- inferior mediastinum
a. anterior mediastinum
b. middle mediastinum
c. posterior mediatinum
What is present in the superior mediastinum
- arch of aorta
- brachiocephalic trunk
- left subclavian branch
- right and left brachiocephalic veins
- inferior part of the superior vena cava
- right and left phrenic nerves
- right and left vagus nerve
- trachea
- esophagus
- thymus gland
- thoracic duct
What are the major branches of the superior mediastinum
- arch of aorta
- brachiocephalic trunk
- left subclavian vein
What is in the brachiocephalic trunk
we have 2 brachiocephalic veins but there is only 1 brachiocephalic artery
Where is the esophagus located in the mediatinum
posterior and superior mediatinum
What is present in the posterior mediatinum
-descending aorta, right and left vagus nerve, thoracic duct, esophagus, sphlanchnic nerves
What is present in the middle mediastinum
heart, pericardium, right and left phrenic nerves
What is present in the anterior mediastinum
thymus
Describe the orientation of the heart
base of the heart faces posteriorly and the apex points anteriorly and slightly towards the left
What are the surfaces of the heart
- anterior surface= sternocostal surface
- inferior surface =diaphragmatic surface, it leans on the diaphragm
- left and right surface= pulmonary surface
- posterior surface= base of heart
What are the 2 major grooves of the heart
A. interventricular sulcus
1. anterior interventricular sulcus
2. posterior interventricular sulcus
B. coronary sulcus
Where are these structures located
a. anterior interventricular sulcus
b. posterior interventricular sulcus
a. anterior surface/sternocostal surface
b. inferior/diaphragmatic surface
Interventricular sulcus
separates the ventricles
What is the auricle , where do you find it
small sac on top of the atrium
What is the coronary sulcus
it encircle the heart and separate the atria from the ventricles
What is the shallow fossa that separates the left and right atrium
fossa ovalis
What is the muscles in the ventricles
trabeculae carnea ( does not produce hormones unlike those muscles of the atria - pectinate muscles)
contraction of atria is equal to?
auricles are only part of the atria that have muscle tissue
What are papillary muscles
subdivision of trabeculae carnea, attach to walls of ventricles and the other attaches to the chorda tendinae
What is the function of papillary muscles
- keep the atrioventricular valve closed during ventricular systole ( prevent it from inverting to atria).
How many layers cover the heart
Almost 3 layers
What covers the heart
pericardial sac that contains the fibrous pericardium and inner serous layer
What is a serous membrane
CT that secretes serous fluid that helps lubricate organs
What is the function of the fibrous pericardium
mechanical protection and surrounds the heart and attaches to the central tendon and diaphragm
What are the layers of the serous pericardium?
- parietal layer: lines the inner surface of the fibrous pericardium
- visceral layer/epicardium: attaches to surface of heart
What is cardiac tampanade
serious buildup of serous fluid in the pericardial cavity that causes increased pressure along the pericardium.
