The mediastinum contains ________ except for the lungs?
All the thoracic viscera and structures except the lung
The mediastinum extends from the ____________ to the __________ inferiorly.
superior thoracic aperture to the diaphragm inferiorly
The pericardium and its contents (heart and roots of its great vessels) are located in what compartment?
middle mediastinum (Dr U says inferior middle)
The ________ is a fibroserous membrane that covers the heart and the beginning of its great vessels
The pericardium is a closed sac with two layers, what are the two layers?
Fibrous pericardium: tough external layer continuous with the central tendon of the diaphragm, inner surface is lined with a parietal layer of serous pericardium.
Serous pericardium is composed mainly of mesothelium, a single layer of flattened cells forming a epithelium that lines the fibrous pericardium and the outer surface of the heart.
The heart arises from _________?
splanchnic mesoderm called cardiogenic area, anterior to the buccopharyngeal membrane and neural tube
How is the heart and pericardium formed?
- the embryonic heart tube invaginates the double layered pericardial sac (like a hot dog in a bun). the heart then "loops" ventrally bringing arterial and venous ends together creating primordial transverse pericardial sinus (T) between them.
- With growth of the embroy the veins spread and expand apart inferiorly and laterally. IVC = inferior vena cava. SVC = superior vena cava.
The right side of the heart receives? from what vessels?
venous, poorly oxygenated blood from the SVC and IVC, pumping it through the pulmonary trunk and arteries to the lungs for oxygenation.
*KNOW THESE VESSELS
Left side of the heart receives what? from what? easy!!!
well-oxygenated (arterial) blood from the lungs through pulmonary veins and pumps it into the aorta for distribution to the body.
The great vessels of the heart originate from what side?
the superior side dummy.
Easy Questions: The heart is a ___________
double, self-adjusting suction and pressure pump, the parts of which work in unison to propel blood to all parts of the body.
Pulmonary arteries carry ________blood to the lungs?
poorly oxygenated! don't forget this easy questions
Veins carry __________blood to the heart
poorly oxygenated (deoxy) blood
carry __________blood to the heart
oxygenated blood! easy don't miss this!!!!!!
What are the 5 steps of the cardiac cycle?
- 1) diastole begins with closure of the aortic and pulmonary valves
- 2) beginning diastole tricuspid and mitral valve open allowing blood to come from pulmonary veins and the vena cava
- 3) atrial contraction during final moments of diastole
- 4) closure of the tricuspid and mitral valves, soon after systole begins
- 5) opening of pulmonary and aortic valves indicates systole (contraction)
Outer lining (surface) of the heart is called what?
epicardium (visceral pericardium) made of MESOTHELIUM
The inner lining of the heart is called what? This lining also covers what component of the heart?
- it also covers the valves of the heart*
it is made of endothelium and subendothelial CT
___________ is a thick, helical middle
layer composed of cardiac muscle
The walls of the heart consist mostly of what layer?
*especially true in the ventricles.
When the ventricles contract they produce what sort of motion and why?
wringing motion because of the double helical orientation of the cardiac muscle fibers!
Your atria are ________chambers
Your ventricles are ________chambers
The cardiac cycle begins with _________ called _____ & ___________called___________.
ventricular filling called diastole & ventricular emptying called systole
The anterior (sternocostal) surface of the heart is formed mainly by _____________.
the right ventricle!
The diaphragmatic (inferior) surface of the heart is formed mainly by ________________.
the left ventricle and partly by the right ventricle
The right pulmonary surface of the heart is formed by ________
mainly the left ventricle
What is the apex of the heart? What costal space is it located? Very important!
Inferolateral part of the left ventricle******KNOW
Located posterior to the left 5th intercostal space at the mid clavicular line.
What sound is maximal at the apex of the heart?
MITRAL VALVE SOUNDS!
* remember the mitral valve is the inferolateral part of the LEFT ventricle
What costal space is the apex of the heart and mitral valve best heard?
posterior to the 5th left intercostal space at the mid clavicular line
Base of the heart is the heart's ________ aspect (opposite of the apex)
The base of the heart is formed mainly by the _________ and a lesser contribution by the _______.
mainly by the left atrium and lesser contribution from the right atrium
The apex beat is where the sounds of the mitral valve closure are maximal and can be auscultated on the throacic wall at what location?
POSTERIOR to the left 5th intercostal space in adults, approx 9 cm (hand's breadth from the median plane)
Posterior surface of the base of the heart faces what vertebrae?
Posterior surface of the base of the heart is seperated by what from what vertebrae?
separated by pericardium, oblique pericardial sinus, esophagus and aorta from vertebrae T6-T9
The base of the heart extends to what? superiorly and inferiorly?
the bifurcation of the pulmonary trunk superiorly and the coronary sulcus inferiorly
The base of the heart receives what vessels?
Pulmonary veins from the LEFT and RIGHT (from the lungs) side of its left atrial portion and inferior venae cavae at the superior and inferior ends of its right atrial portion
The base of the heart receives how many pulmonary veins?
FOUR total, 2 left, 2 right (superior and inferior pulmonary veins)
What makes up the right
border of the heart?
Right Atrium, extending from SVC & IVC
What forms the left border
of your heart?
Left Ventricle and slightly by the left auricle (a muscular appendage attached to the left atrium)
The inferior border of the heart is formed by?
Right Ventricle and slightly the left ventricle
Superior border of the heart is formed by what?
Right and Left Atria and Auricles
What is the pulmonary trunk? look at the picture!!
5 cm long and 3 cm wide, it is the arterial continuation of the right ventricle
, dividing into the left and right pulmonary arteries (deliver low-oxygen blood to the lungs for oxygenation)
Where is the apex of the heart?
5th LEFT intercostal space in midclavicular line
Where is the superior border of the heart?
Second left intercostal space to the third right costal cartilage
Where is the right border of the heart located?
3-6th right costal cartilage.
Where is the left border of the heart located?
2nd left costal cartilage to the apex of the heart
Inferior border of the heart location?
6th Right costal cartilage to the APEX.
Where do you listen for the pulmonary valve?
#1 in picture, Medial end of left 2nd intercostal space
Where do you listen for the Aortic
#2 in picture, Medial End of RIGHT 2nd Intercostal Space
Where do you listen for the tricuspid valve
#3 in picture, just left of the lower part of the sternum, near 5th intercostal space
Where do you listen for the mitral valve?
Over apex of heart, in left 5th intercostal space at midclavicular line
The right atrium receives blood from the superior vena cava at what level?
3rd costal cartilage!
The right atrium receives blood from the inferior vena cava and coronary sinus at what level?
5th costal cartilage
What is the right auricle and what the heck is its purpose??
it is an ear-like conical muscular pouch that projects from the right atrium like an add-on room, increasing the capacity of the atrium
The right atrium discharges poorly oxygenated blood into the right ventricle through the ___________
RIGHT A/V orifice
portion of the right atrium contains what?
- openings for the SVC, IVC and coronary sinus
- Right A/V orifice
- Valves of IVC and coronary sinus
- Smooth and Rough parts separated by crista terminalis (inside) and sulcus terminalis (outside)
- Interatrial septum containing the fossa ovalis which is a remnant of the oval foramen (look at picture)
Inside the right atrium you have rough ________?
muscular pectinate muscles
What are the most important structures of your RIGHT ventricle?
- Conus Arteriosus (infundibulum): cone-like space leading into the pulmonary trunk
- Trabeculae carneae: irregular muscular elevations (rough)
- Supraventricular crest: thick muscular ridge, separates rough part from smooth part.
- ***Tricuspid Valves: attached to papillary muscles by chordae tendineae