Respirator, Middle Mediastinum Flashcards
Where is the sinoatrial node found? Atrioventricular?
SA = group of cells positioned on the wall of the right atrium, near the entrance of the superior vena cava. AV - between the RIGHT atrium and RIGHT ventricle
What are the 4 boundaries of the MIDDLE Mediastinum? What is found within this structure?
- Superiorly = STERNAL ANGLE (T4 –> 2nd rib) 2. Inferiorly = XIPHISTERNUM (T9) 3. Laterally on the left = 5th intercostal space in midaxillary line* (where Bicuspid valve is) 4. Laterally on the RIGHT = Along sternal border HEART IS INSIDE THE MIDDLE MEDIASTINUM (mediastinum = space between right & left pleural cavities of the lungs)
What is the pericardium? What is the progression of the layers of the pericardial sac?
- closed sac containing serious fluid for lubrication Pericardial Sac: Fibrous Layer –> Parietal –> Serrous Fluid/ Pericardial Cavity –> Visceral layer
What two layers are continuous with one another within the pericardial sac? They are both composed of a _______ epithelium.
Visceral (Epicardium) & Parietal* SEROUS Epithelium
At what two areas are the visceral and parietal layers continuous with one another?
Transverse Sinus - at the entry of 4 pulmonary veins & Oblique Sinus - below the pericardial reflection between the pulmonary veins
Where are both sinuses located and how can they be accessed?
located POSTERIORLY - accessed ONLY from the LEFT SIDE* (the pericardial reflections of the superior and inferior vena cavae block the right side)
Describe the pathway of blood circulation within the heart (include the valves in the progression and where blood is oxygenated & deoxygenated)
1 –> Superior & Inferior Vena Cavae [Deoxygenated blood] 2 –> goes into the RIGHT ATRIUM 3–> through the TRICUSPID valve 4 –> enters the RIGHT VENTRICLE 5–> Exit via the PULMONARY SEMILUNAR Valve* 6 –> [Oxygenated] blood returns to the LEFT ATRIUM via R_ight and Left Pulmonary VEINS_ 7 –> through the BICUSPID VALVE enters the 8 –> LEFT VENTRICLE 9–> exits left ventricle through AORTIC SEMILUNAR VALVE into the 10–> AORTA
What are the 6 major structures found in the RIGHT Atrium?
- Fossa Ovalis –> remnant of foramen vale = fetal shunt
- Musculi Pectini –> ridges on the walls of the atria
- Opening of the CORONARY SINUS
- Crista Terminalis –> SA Node & origin for pectinate muscles
- Valve of Inferior Vena Cavae
- Openings for Superior and inferior Vena Cavae
What are the 5 major structures of the Right VENTRICLE?
- Tricuspid Vlaves (anterior/posterior/septal*mostmedial)
- Chorda Tendinae –> string like & arise from papillary muscle
- Papillary Muscles
- Trabeculae Carnae
- Moderator Band (septomarginal trabeculae)
What are the two major components of the LEFT ATRIUM?
- Valve of foramen ovale
- Openings for PULMONARY VEINS
What are the 4 major structures of the LEFT VENTRICLE?
- Bicuspid Valves (anterior & posterior)
- Chorda tendinae
- Papillary Muscles
- Trabeculae Carnae
Where are the papillary muscles, chorda tendinae, and trabeculae carnae found in the heart?
BOTH right and left VENTRICLES
What is the one component of the RIGHT VENTRICLE that is not found anywhere else in the heart? What does it connect?
Moderator Band (Septomarginal Trabeculae)
-connects the interventricular septum to the anterior papillary muscle
Where would one find the opening to the coronary sinus?
Right Atrium
What node inititates contraction of the heart?
SA Node
What is the function of the papillary muscles?
prevent prolapse of the tricuspid valve leaflets during ventricular SYSTOLE
(aka: blood from pushing back up into the atrium)
What two structures does the chorda tendinae connect?
Papillary Muscles to the tricuspid & bicuspid valve
Where is the only place that the Pectinate Muscles are found? Where do these muscles originate from?
RIGHT ATRIUM
- originate fromCrista Terminalis (SA Node ridge)
Name the branches of the Left Coronary Artery.
- Left Anterior Descending Artery/ Interventricular A. (LAD)
- Circumflex Artery
- Left Marginal Artery
Name the branches of the RIGHT Coronary Artery.
- Right Posterior Descending/ Interventricular Artery
- RIGHT MARGINAL ARTERY (tagged often)
What are the 4 main Cardiac veins?
- Great Cardiac V.
- Middle Cardiac V.
- Cardiac Sinus
- Small Cardiac V.
The Great Cardiac Vein travels with what Artery?
LAD
Left Anterior Descending / Interventricular
What artery dos the Middle/Marginal Cardiac Vein travel with?
Posterior Interventricular/Descending
What artery does the Small Cardiac Vein Travel with?
Right Marginal Branch
All Cardiac Veins drain into the Coronary Sinus. True or False
FALSE
all BUT Anterior Coronary Veins (branches of Small Cardiac Vein)
Where does the coronary sinus drain into?
RIGHT ATRIUM
Which artery travels within the CORONARY SULCUS?
Circumflex branch of LEFT CORONARY Artery
What structure separates the right and left VENTRICLES?
Interventricular Septum
Which artery is refered to as the widow maker?
LAD
Parasympathetics of the heart travel via the ________. They speed up or slow down the heart rate?
VAGUS NERVE = SLOW DOWN HEART RATE
- LEFT recurrent laryngeal around AORTA
Right Recurrent Laryngeal around the Subclavian Artery
Sympathetics of the heart travel via the ________. They speed up or slow down the heart rate?
Post-ganglionic fibers from T1-T5 to the cardiac plexus
= INCREASE heart rate
During a myocardial infarction, upon which dermatome and which part of the body is pain being transmitted?
T1 Dermatome
- pain on the LEFT upper limb (most likely)
Which node is usually referred to as the pacemaker of the heart?
SA Node - in the wall of the Right Atrium
What is the function of the AV Node? How do impulses get transmitted in the heart
Receives impulses from SA node
- SA–> AV–> AV bundle of HIS
- this includes the Moderator Band
Av node is found in the wall of the Right atrium and ventricle
Where is the projection of the Pulmonary Semilunar Valve? Where is its AUSCULTATION?
- 2nd costo-sternal junction on the left
- 2nd intercostal space to the LEFT of the sternum
Where is the projection of the Aortic Semilunar Valve? Where is its AUSCULTATION?
a) 3rd Costo-Sternal junction on the LEFT
b) 2nd intercostal space to the RIGHT of the sternum
Where is the projection of the Bicuspid Semilunar Valve? Where is its AUSCULTATION?
a) 3rd intercostal space to the LEFT of the sternum
b) 5th intercostal space on the left at the Mid-Clavicular Line (mid-axillary)
Where is the projection of the Tricuspid Semilunar Valve? Where is its AUSCULTATION?
a) behind sternum at 4th rib
b) 5th intercostal space to the left of the sternum (more medial than the Bicuspid/Mitral Valve)
At what vertebral level does the trachea divide?
- Traches divides at the STERNAL ANGLE (T4/T5, 2nd rib)
What vertebral level is the diaphragm at?
L2
What is the Ligamentum Arteriosum? What is its clinical significance?
LIGAMENTUM ARTERIOSUM = left over from birth (Ductus Arteriosum) –> functioned to shunt blood away from the lungs (connected pulmonary trunk to the Aorta)
*Aortic Aneaurysm (bulge) can compress LEFT recurrent laryngeal
- leading symptom of Aortic Aneurysm = horseness of the voice
The Pleura around the Lungs and the Pericardium around the heart are both ______ membranes. What are the 3 aspects that contribute to this classification?
Serrous Membranes
Contain:
- Parietal Layer (outside portion- in heart it is part of fibrous portion)
- Visceral layer (laying directly on the organ, inside the cavity)
- Serrous fluid in between both
If surgeon needs to access the back of the heart, which direction does he come from and why?
LEFT because of the barrier of pericardium on the right side
The auricle is found on_____ & ______
Right and Left Atrium
Does theSuperior Vena Cava have valves?
No valves that protect the SUPERIOR VENA CAVAE (gravity pulls down), INFERIOR VENA CAVAE has a small valve to prevent blood from being regurgetated
What is the fossa ovalis?
FOSSA OVALIS = remnant of fetal circulation in the heart
- SHUNT blood away from the lungs in the fetus directly from RIGHT ATRIUM into LEFT ATRIUM
What is the difference between the pectinate muscles in the Right atrium and the trabeculae carnae in the right and Left ventricles?
NO DIFFERENCE –> different name, but same function
PECTINATE MUSCLES = trabecular carnae in the ventricles
- function to contract the spaces
Chorda tympani + papillary muscles keep_______ from regurgitating into the ATRIA upon contraction of the ventricle (contract on SYSTOLE)
TRICUSPID VALVE
What coordinates contraction of the Anterior Papillary Muscles?
Moderator Band* (TEST)
What is the source of heart murmurs?
Bicuspid Valve
What artery supplies the right and left ventricle?
Anterior Interventricular Artery (Left Anterior Descending: LAD)
Filling of the heart is greatest during Systole or Diastole?
DIASTOLE
-heart refills after contraction
IN the SA and AV nodes there are both parasympathetic fibers and sympathetic fibers. True or False?
True!!
- function to decrease and increase heart rate
What arteries do the Left and Right Marginal Branches come off of ?
- LEFT = Circumflex branch
- RIGHT = directly off the Right CORONARY A.
During cardiac catheterization, the physician watches the blood flow from the right ventricle
into which of the following:
A: Aorta
B: Left coronary A
C: Inferior Vena Cava
D: Pulmonary Trunk
E: Pulmonary Veins
D: Pulmonary Trunk
Patient’s LAD artery is occluded. Which area of the heart is affected by this obstruction? LAD = widow maker
A: porterior portion of left ventricle
B: The anterior interventricular septum and the anterior ventricles
C: Left Atrium
D: Right atrium only
E: Both the SA and AV nodes
B: THe anterior interventricular septum and the anterior ventricles
In Which heart chamber would you find the moderator band?
A: Right atrium
B: Right ventricle
C: Left Atrium
D: Left Ventricle
B: Right Ventricle
In order to auscultate the bicuspid valve, you would place your stethoscope:
A: Second intercostal space to the right of the sternum
B: Second intercostal Space to the left of the sternum
C: Fourth intercostal space to the right of the sternum
D: Fifth intercostal space to the right of the sternum
E: Fifth intercostal space in the mid-axillary line
E: 5th intercostal space in the mid-axillary line
The arch of the aorta is found at what vertebral level?
T4/T5
What are the typical ribs? Which ribs are the floating ribs? WHich ribs join via the COSTAL MARGIN?
- Typical ribs = 3-9 (both ends can touch the table)
- Last 2 = floating ribs
- Ribs 7,8,9,10 join via the Costal Margin (1-6 join the body of the sternum)
The Internal Thoracic artery splits off into what two branches? What thoracic arteries does it also supply?
- Superior Epigastric & Musculophrenic
- Anterior Intercostal A.
The Posterior Intercostal Arteries come off of ______
the Descending Aorta
The base of the heart is found on the right or left side? The apex is at what point?
LEFT
- Apex = 5th intercostal space on the LEFT
What veins are the only veins with oxygenated blood?
Pulmonary veins (return back from the lungs into the Left Atrium)
What connects the septum to the Anterior Papillary Muscles?
Moderator Band (Septomarginal Band)
Which statement is true of the right atrioventricular valve?
it is also called the mitral valve
it is open during ventricular diastole
it transmits oxygenated blood
it is opened by the pull of chordae tendineae
it consists of 2 leaflets
it is open during ventricular diastole
(during ventricular systole - the pulmonary and aortic valves are open)
Which heart valve has leaflets described as “anterior, left and right”?
Aortic
Pulmonary
Left atrioventricular
Right atrioventricular
Pulmonary
(Aortic are POSTERIOR, left & right)
Elevated systolic blood pressure in the right ventricle suggests stenosis of which valve?
Aortic
Mitral
Pulmonary
Tricuspid
Pulmonary