Exam 4- Heart and Circulatory System Flashcards
What is the heart protected by anteriorly?
Sternum
What is the heart protected by laterally?
- The Ribs
- Intercostal muscles
- Lungs
What is the heart protected by posteriorly?
Thoracic vertebrae
What is the tough connective tissue sac the heart is encased in called?
Pericardium
What is the cardiac muscle of the heart referred to as?
Myocardium
What is the epithelial tissue lining the internal chambers of the heart referred to as?
Endocardium
What does the outer layer of the pericardium blend with inferiorly?
Central tendon of the diaphragm inferiorly
What does the fibrous layer of the pericardium blend with superiorly and posteriorly?
The major blood vessels of the heart (the vena cava, aorta and pulmonary trunk)
Where is the base located on the heart?
Superiorly and posteriorly
Where is the apex located on the heart?
points inferiorly and to the left
Where is the apex located in relation to the costal cartilages?
It lies at the level of the left 6th costal cartilage
What is the shape of the apex?
rounded projection of the heart
What are the great vessels of the heart?
- Aorta
- Pulmonary Trunk
- Vena Cava
Where do the great vessels of the heart attach at?
base of the heart
What are the left and right auricles? Where are they attached to the heart?
- Appendages
2. Lateral surfaces of the atria
What is the function of the auricles?
The auricles increase the internal surface area of the left and right atria
What does the superior vena cava drain?
- Head
- Neck
- Upper limbs
(thorax)
What forms the superior vena cava? Where does it drain?
It is formed as the left and right brachiocephalic veins join together and empties into the right atrium
What does the aorta supply?
The entire body with blood
What does the aorta originate as?
originates at the aortic semilunar valve within the left ventricle of the heart
What are the different regions the aorta is divided into?
- Ascending Aorta
- Aortic Arch
- Descending Aorta
What is the path of the ascending aorta?
leads from the heart and courses superiorly
What is the path of the aortic arch?
courses posteriorly and to the left giving off its major branches
What is the path of the descending aorta?
courses posterior to the heart as it descends through the thorax
Where does the pulmonary trunk lead from?
Right Ventricle
What is the function of pulmonary trunk?
carries deoxygenated blood from the heart to the lungs for reoxygenation
Where does the inferior vena cava receive blood from? Where does it enter the heart?
- Receives blood from the lower limbs, pelvis and abdomen
2. Enters the right atrium of the heart inferiorly
What does pulmonary circulation refer to? (pathway)
Pulmonary circulation refers to the pathway of blood from the right side of the heart to the lungs and, from the lungs back to the left side of the heart
What does the pulmonary trunk bifurcate into?
The left and right pulmonary arteries
Describe the flow of pulmonary circulation. (generally)
- Blood flows through the pulmonary trunk (which then bifurcates into the left and right pulmonary arteries)
- The pulmonary arteries carry DEOXYGENATED blood to the lungs where blood will exchange CO2 for O2
- Once the blood has been reoxygenated in the lungs, it returns to the left atria of the heart (via the 4 pulmonary veins)
What do the 2 pulmonary arteries carry?
DEOXYGENATED blood to the lungs (where blood will exchange CO2 for O2)
What are the only arteries that carry deoxygenated blood in the body?
Pulmonary Arteries
Once blood has been reoxygenated in the lungs where does it return to, and how?
- Left atria of the heart
2. Via the 4 pulmonary veins
What are the only veins in the body that carry oxygenated blood?
Pulmonary Veins
Generally where do arteries carry blood?
AWAY from the heart
Generally where do veins carry blood?
TO the heart
What does coronary circulation refer to?
The blood supply to the myocardium of the heart itself
GENERALLY where do the left and right coronary arteries of the heart lead to?
Left and right sides of the heart respectively
Where does the right coronary artery originate from?
Right side of the aorta (aortic sinuses)
What are the two branches of the right coronary artery?
- Right Marginal Branch
2. Posterior Interventricular Branch
How does the right coronary artery terminate?
terminates posteriorly by anastomosing (joining) with the CIRCUMFLEX BRANCH of the left coronary artery
Where does the left coronary artery originate from?
Left side of the aorta (aortic sinuses)
What does the left coronary artery bifurcate into?
- Circumflex Branch
2. Left anterior descending artery (Anterior Interventricular Branch)
What are the veins draining the myocardium of the heart called?
Cardiac Veins
How many major cardiac veins are there? Where do these veins all drain into?
- 3
2. Coronary Sinus
What are the names of the 3 major cardiac veins?
- Great Cardiac Vein
- Small Cardiac Vein
- Middle Cardiac Vein
Describe the coronary sinus.
short, wide vessel that receives all 3 cardiac veins
Where does the coronary sinus empty into?
Directly into the right atrium
What are the anterior cardiac veins?
2 or 3 small vessels which drain the right ventricle and end directly in the right atrium
What are the venae cordis minimae
Numerous small veins that drain the myocardium itself and empty separately into all 4 chambers of the heart
What does the right atrium receive and from where?
- Deoxygenated blood
2. All parts of the body
How many major veins drain into the right atrium of the heart?
3 (through three openings)
Name the openings through which major veins drain into the right atrium of the heart?
- Superior vena caval opening
- Inferior venal caval opening
- Opening of the coronary sinus
What is the crista terminalis? Where is it found? What part of the right atrium?
- A vertical muscular ridge
- Right atrium/Left and Right Auricles
- Posterior wall of the right atrium
What is the musculi pectinati (pectinate muscle)? Where are they found?
- Muscular ridge like projections extending from the crista terminalis
- These are found within the right atrium and in the right and left auricles
What is the partition between the right and left atria called?
Interatrial Septum
On the Interatrial Septum on the right ventricle what is the oval depression called?
Fossa Ovalis
What is the fossa ovalis surrounded by at its periphery?
Ridge called the limbus fossa ovalis
What is the fossa ovalis a remnant of?
a foramen that, in the fetal stage of development, existed between the right and left atrium called the FORAMEN OVALE
When does the foramen ovale usually close?
At birth
Anteriorly, what does the right atrium open to?
The right ventricle (via the Right Atrioventricular Opening)
What opens the right atrium to the right ventricle? What is this guarded by?
- Right Atrioventricular Opening
2. Right Atrioventricular valve or tricuspid valve (which consists of 3 cusps)
How many parts are atrioventricular valves composed by and what are their names?
3 Parts:
- Cusps
- Chordae Tendineae
- Papillary Muscles
What are cusps?
flaps of connective tissue
What are chordae tendineae?
connective tissue cords that attach to the lower surface of the cusps
What are papillary muscles?
internal folds of ventricular muscle that give off attachments to the chordae tendineae
Papillary muscles are a specialized type of what?
trabeculae carneae
What does the internal surface of the right and left ventricles consist of?
irregular projections of muscle called trabeculae carneae
What are the two types of trabeculae carneae?
- Papillary muscles
2. Septomarginal trabeculae
What is septomarginal trabeculae? What does it contain?
- Band of tissue that attaches the interventricular septum to the papillary muscle
- Contains important nerve fibers of the conduction system of the heart
What are the openings of the right ventricle?
- Right Atrioventricular opening (guarded by the tricuspid valve)
- Opening to the pulmonary trunk
How does blood leave the right ventricle?
enters the pulmonary trunk by passing through the pulmonary semilunar valve
What is the difference between semilunar and atrioventricular valves?
Semilunar valves DO NOT possess papillary muscles and chordae tendineae
For each semilunar valve how many cusps are there?
3
What is a nodule?
Small central thickening of fibrous tissue on the free edge of each cusp
What is the lunula
narrow thin crescent area extending from each side of the nodule
What are the spaces between the cusps and the wall of the vessel called?
Sinuses
Following the pulmonary semilunar valve where does blood travel? Where does it then course?
- Blood will enter into the:
1. Pulmonary trunk
2. Pulmonary arteries - These then enter the lungs
How does reoxygenated blood from the lungs reenter the heart? At what specific part of the heart do these enter?
- Pulmonary veins
2. Left atrium
The internal surface of the left atrium is smooth except within the left auricle which contains _____
musculi pectinati (crista terminalis)
What is the majority of the surface of the left atrium taken up by?
4 separate openings of the pulmonary veins
In total what are the openings of the left atrium?
- 4 separate openings of the pulmonary veins
2. Left Atrioventricular Opening
What is the Left Atrioventricular Opening guarded by?
The bicuspid valve (mitral valve, left atrioventricular valve)
What is the composition of the bicuspid valve?
2 cusps with supporting papillary muscle connected via chordae tendineae
Where does blood flow after the left atrium?
through the bicuspid valve and into the left ventricle
What is a major difference between the left and right ventricles?
The wall of the left ventricle is usually twice as thick as that of the right
What happens when the left ventricle contracts?
blood will leave the heart and enter the aorta
What is the opening to the aorta guarded by?
Aortic Semilunar Valve
How many cusps does the aortic semilunar valve contain?
3 (which possess nodules, lunulae and sinuses as did the pulmonary semilunar valve)
What are the spaces between the cusps of the aortic semilunar valve and the wall of the aorta called?
aortic sinuses
What is a generalization of the direction of blood flow?
- Right atrium
- Tricuspid valve
- Right ventricle
- Pulmonary semilunar valve
- Pulmonary trunk
- Pulmonary arteries
- Pulmonary veins
(Lungs) - Left atrium
- Bicuspid valve
- Left Ventricle
- Aortic semilunar valve
- Aorta
Describe the conduction of the heart.
- Initiates at the Sinuatrial Node (SA node)
- Impulse is carried to the atrioventricular node (AV node)
- Carried down to the Atrioventricular Bundle (of HIS)
- Carried down to the Left and Right Bundle branches
- Finally to the purkinje fibers (which radiate throughout the ventricles)
What is parasympathetic innervation of the heart supplied by?
Vagus Nerve (CN X)
What neurotransmitter is involved in slowing the heart rate down?
Acetylcholine (Ach)
How does Ach slow the heart rate down?
Ach is released at the SA node and will act to decrease the rate and intensity of myocardial contractions thus, slowing the heart rate
What is sympathetic innervation of the heart derived by?
Sympathetic Chain Ganglion (located on ether side of the spinal column)
What neurotransmitter is involved in increasing the heart rate?
Norepinephrine
How does norepinephrine increase heart rate?
It is released directly to the myocardium of the ventricles will result in increased heart rate
What is the first main branch off the aortic arch?
Brachiocephalic trunk
What does the brachiocephalic trunk branch out to?
- Right subclavian artery
2. Right common carotid artery
What does the right subclavian artery branch from? What does it supply?
- Brachiocephalic Trunk
2. Right upper limb
What does the right common carotid artery branch from? What does it supply?
- Brachiocephalic Trunk
2. Right side of the head
What is the second branch off the aortic arch? What does it supply?
- Left common carotid artery
2. Left side of the head
What is the final branch off the aortic arch? What does it supply?
- Left Subclavian Artery
2. Left upper limb
What 2 arteries give supply to the head and neck?
- Common carotid arteries
2. Vertebral arteries
What do the left and right external carotid arteries branch from? How many branches do they give off? What are 3 of those branches?
- Common carotid arteries
- 8
- Facial artery, maxillary artery and superficial temporal artery
What do the internal carotid arteries branch from? Where do they enter the cranial cavity at?
- Common carotid arteries
2. Carotid Canal
What are the vertebral arteries a branch of?
Subclavian arteries
How do the vertebral arteries ascend through the neck?
By coursing through the transverse foramina of the cervical vertebrae
What arteries join together to form the circle of willis?
- Internal carotid arteries
2. Vertebral arteries
What does the circle of willis supply?
Internal cranial cavity
What do the left and right subclavian arteries course between?
the clavicles and the first ribs
When the subclavian arteries cross over the inferior border of the first rib what do they change their name into?
Axillary Arteries
How many branches do the axillary arteries give off? What do they supply?
- 6
2. Shoulder region
As the axillary arteries reach the inferior border of the teres minor muscle, what does their name change to?
Brachial Arteries
What is the profunda brachii artery a branch of? Where do they course? What does it supply?
- The brachial arteries
- Posterior to the humerus
- Posterior tissues of the arm
Where does the brachial artery terminate, and what does it branch off to?
- Anterior to the elbow
2. Radial/Ulnar arteries
Where does the ulnar artery terminate, and what does it form?
- Palm of the hand
2. Superficial Palmar Arch
What does the radial artery pass through?
Anatomical snuff box
Where does the radial artery terminate, and what does it form?
- Palm of the hand
2. Deep Palmar Arch
What are the internal thoracic arteries a branch of?
Left and Right Subclavian arteries
What do the internal thoracic arteries give off?
Anterior intercostal arteries
What are the anterior intercostal arteries a branch of? What do they supply?
- Internal thoracic arteries
2. Internal thoracic tissues and Intercostal muscles
What do the posterior intercostal arteries arise from? What do they supply?
- Small branches from the descending aorta
2. Skin of the lateral and anterior chest wall AND intercostal muscles
How does the descending (abdominal) aorta enter the abdomen?
By traversing the aortic hiatus of the diaphragm at the level of T12
Where does the descending (abdominal) aorta terminate?
Level of L4
What do the branches of the descending (abdominal) aorta supply?
The descending aorta gives off many branches that supply the organs and viscera of the abdomen
Where does the celiac trunk arise from?
short vessel that arises from the aorta immediately below the aortic opening of the diaphragm
What are the direct branches that the celiac trunk gives off?
- Left Gastric Artery
- Splenic Artery
- Common Hepatic Artery
What do the branches of the celiac trunk supply?
Tissues of the:
- Liver
- Gallbladder
- Spleen
- Pancreas
- Stomach
- Duodenum (first portion of the small intestine)
Where does the superior mesenteric artery arise from? What does it supply?
- Aorta just below the celiac trunk
2. Small intestine and Portions of the large intestine
What doe the renal arteries branch from? How do they course?
- Descending abdominal aorta
2. Course laterally where they enter into the kidneys
How is blood flowing into the kidneys through the renal arteries filtered of impurities?
It is filtered of impurities and returned to the circulatory system via the renal veins
What are the gonadal arteries also known as?
Testicular/Ovarian arteries depending on gender
What are gonadal arteries branches of? What do they supply?
- Small branches from the descending aorta
2. Reproductive organs
What do the inferior mesenteric arteries arise from? What do they supply?
- Aorta a few centimeters above its bifurcation
2. Descending colon, sigmoid colon, and rectum
Where does the descending aorta terminate? What does it bifurcate into here?
- Level of L4
2. Left and right common iliac arteries
What do the common iliac arteries bifurcate into?
Internal and external iliac arteries
What do the internal iliac arteries and their branches supply?
pelvic, genital and gluteal regions
What are the superior and inferior gluteal arteries a branch of? Where do they course through? What do they supply?
- Internal iliac arteries
- Course through the greater sciatic notch
- Gluteal region
Where do the external iliac arteries courses deep to?
Inguinal Ligament
When does the external iliac artery change its name to the femoral artery?
As it courses deep to the inguinal ligament and enters the femoral triangle
What is the femoral artery a continuation of?
External iliac artery
What do they branches of the femoral artery supply?
tissues and musculature of the anterior and medial thigh
What is the profunda femoral artery a branch of?
femoral artery
What does the profunda femoral artery give off?
perforating branches which course through the adductor magnus muscle
What do the perforating branches of the femoral artery supply?
tissues of the posterior thigh
As the Femoral Artery courses distally along the thigh what does it pass?
Passes through the adductor opening and courses into an area posterior to the knee called the Popliteal Fossa
Where does the femoral artery change its name to the popliteal artery?
When it courses into the popliteal fossa
What is popliteal artery a branch of?
Femoral artery
What is the anterior tibial artery a branch of? What does it supply?
- Popliteal artery
2. Anterior leg muscles
Where does the anterior tibial artery change its name? What does it change its name to?
- As it crosses an imaginary line between the medial and lateral malleolus
- Dorsalis Pedis Artery
What does the dorsalis pedis artery supply?
Dorsum (top) of the foot
What is the posterior tibial artery a branch of? What does it supply?
- Popliteal artery
2. Posterior leg muscles
Where does the posterior tibial artery bifurcate into the medial and lateral plantar arteries?
After is passes deep to the flexor retinaculum
What are the medial and lateral plantar arteries derived from? What do they supply?
- Posterior tibial artery
2. Tissues and musculature on the sole of the foot
What do the medial and lateral plantar arteries course with?
Medial and lateral plantar nerves
What is the fibular (peroneal) artery a branch of?
Posterior tibial artery
What does the fibular artery branches supply?
Ankle and heel BUT DOES NOT ENTER THE FOOT
What is the internal jugular vein a continuation of?
Sigmoid sinus (that drains the cranial cavity)
Where does the internal jugular vein begin?
Jugular formane
What does the external jugular vein arise from?
veins draining the sides of the neck and face
What four veins join together to form the brachiocephalic veins?
- Internal jugular veins (2)
2. Subclavian veins (2)
How is the superior vena cava formed?
As the left and right brachiocephalic veins unite
When do the femoral veins change their name to the external iliac veins?
As they course deep to the inguinal ligament
What forms the common iliac veins?
When the external and internal iliac veins unite
What veins unite to form the inferior vena cava?
Left and right common iliac veins
What does the azygos vein drain? Where does the vein drain into?
- Blood from the right posterior walls of the thorax and abdomen
- Superior vena cava
Where does the azygos vein course along?
Right side of the thoracic vertebrae
Where does the Hemiazygos vein course along?
Left side of the thoracic vertebrae
What does the Hemiazygos vein drain? Where does the vein drain into?
- Blood from the left posterior walls of the thorax and abdomen
- Azygos vein
Where do the superficial veins course through, and where do they carry blood to?
- Subcutaneous tissue
2. Proximally back to the heart
What do the small superficial drains draining the digits joint together to form?
Dorsal Venous Arch on the back of the hand
As the cephalic vein continues on the lateral surface of the arm where does it course along? What happens here?
- Delto-pectoral groove
2. Here, the cephalic vein pierces the fascia and terminates by draining into the axillary vein
Where does the cephalic vein drain into?
Axillary vein
Where does the cephalic vein arise from?
Lateral side of the dorsal venous arch
Where does the basilic vein arise from?
Medial side of the dorsal venous arch
What does the basilic vein join to form the axillary vein when it pierces the brachial fascia of the axilla?
Brachial veins
What veins does the medical cubital vein join?
cephalic and basiilic veins anterior to the elbow
What is the clinical significance of the medial cubital vein?
Typically the vessel used to draw blood
Where do the superficial veins of the lower limbs course in?
subcutaneous tissue layer
Superficial veins of the foot converge on the dorsum of the foot to form what?
dorsal venous arch
What is the longest vein in the body?
Greater Saphenous Vein
Where does the Greater Saphenous Vein arise from?
medial side of the dorsal venous arch
When does the Greater Saphenous Vein terminate? What does it drain into?
- As the greater saphenous vein pierces the fascia in the upper thigh, it terminates
- Femoral vein
Where does the Lesser Saphenous Vein arise from?
lateral side of the dorsal venous arch
What does the Lesser Saphenous Vein drain into as it terminates?
Popliteal vein (posterior to the knee)
What type of valves are nodules, lunula, and sinuses found on?
Semilunar valves
