CVS Anatomy Flashcards
Arteries carry __________ blood _______________ the heart
Arteries carry OXYGENATED blood AWAY FROM the heart
Veins carry ___________ blood ________________ the heart
Veins carry DEOXYGENATED blood TOWARDS the heart
Which artery is an exception and why?
Pulmonary artery
Carries DEOXYGENATED blood away from the heart
Which vein is an exception and why?
Pulmonary vein
Carries OXYGENATED blood toward the heart
What is the function of the cardiovascular system?
- Delivers oxygen and nutrients to tissues
- Equalizes temperature in the body
What is the heart?
4-chambered fibromuscular pump
Where is the heart located?
Middle mediastinum
What are the three parts of the sternum?
- Manubrium
- Body
- Process
What is the first organ to develop in a fetus?
Heart
(develops during the 3rd week of intrauterine life)
What is located in the superior mediastinum?
Ascending aorta
What is located in the inferior mediastinum?
Main heart
Descending aorta
What do ligaments and fibrous structures do?
Ensures that the heart is anchored in place
What surrounds the heart?
Inner: Serous pericardium
Outer: Fibrous pericardium
Where are the ligaments that keep the heart anchored in place attached to?
Attached to the fibrous pericardium
What is the function of the fibrous pericardium?
- Protects the heart
- Anchors the heart (supportive)
Serous pericardium
- Double layered: Parietal layer & Visceral layer (aka epicardium)
- Lining epithelium: Mesothelium
- Shock absorber
What does the pericardial cavity contain?
Contains fluid - cushions the heart (shock absorber)
Contains 15-50 mL of fluid
Which part of the heart is pain sensitive?
- Fibrous pericardium
- Parietal Serous pericardium
- Innervated by Phrenic nerve
E.g. if heart inflammed/irritated = patient will complain of pain
Epicardium
- Visceral layer of serous pericardium
- Attached to the surface of the heart (myocardium)
What is cardiac tamponade?
- Rapidly developing pericardial effusion
- Amount of pericardial fluid increases very fast (>50mL)
- Compresses the heart = ↓ cardiac output + shock
E.g. heart weak (or maybe infection) = hole in heart = blood oozes into pericardial cavity = cardiac tamponade
What is pericardial effusion?
An ↑ in amount of pericardial fluid (any amount >50mL)
What is pericardiocentesis done and what is done?
Cardiac tamponade
Syringe is inserted into the pericardial cavity to remove some pericardial fluid
Where is the right atrium located in relation to the right ventricle?
Right atrium is located on the right side of right ventricle
Which part of the heart is hidden from view when viewed from the front (frontal)?
Left atrium
What chambers form the sternocostal (anterior) surface?
Right atrium
Right atrium
Left ventricle
Small part of the left atrium
What is the part between the right and left ventricle called?
Interventricular sulcus
If anterior, Anterior interventricular sulcus
If posterior, Posterior interventricular sulcus
What chambers form the diaphragmatic (inferior - behind) surface?
Left ventricle
Right ventricle
What chambers form the posterior surface (base)
Right atrium
Left atrium
What forms the apex?
Left ventricle
Where is the coronary sinus located
Somewhere below the left atrium
What does the superior vena cava transport?
Transports deoxygenated blood from head and neck to the heart
What does the inferior vena cava transport?
Transports deoxygenated blood from the rest of the body to the heart
Which chamber does the blood carried by the superior and inferior vena cava enter?
Right atrium
What is the crista terminalis?
Crista terminalis separates the smooth area (where blood flows into) from the rough area (right auricle)
What is the auricle?
Muscular part of atrium
Which chambers receive blood and which chambers pump blood?
Receiving chambers: Atrium (inflow)
Pumping chambers: Ventricles (outflow)
What is the function of the coronary sinus?
Brings deoxygenated blood produced by the HEART into the right atrium to be removed
Where does the right ventricle pump blood to?
Pumps blood through the pulmonary artery to the lungs
Where is the left atrium located?
Back of the heart (posterior)
L. atrium is the closest part of the heart to the oesophagus
Where does the left ventricle pump blood to?
All parts of the body
Therefore more muscular than R. ventricle
Atrium (smooth or rough surfaces): outflow & inflow
Inflow: smooth
Outflow: generally rough (auricles because need to pump to ventricles)
Ventricles (smooth or rough surfaces): outflow & inflow
Inflow: rough
Outflow: smooth (reduce friction)
What is the function of cardiac valves?
Ensures unidirectional flow of blood; prevents backflow
What causes the heart sound?
Blood has the tendency to hit against the mitral (bicuspid) valve
Causes “turbulence” which causes a sound (1st heart sound)
Semilunar valve closes after blood pumped into aorta
Blood hits the valve (trying to backflow but X)
Causes “turbulence” which causes a sound (2nd heart sound)
Pathway of the cardiac conduction system
- Sinoatrial node (SA node) generates electrical impulse
- Electrical impulse flows through the internodal pathways to the atrialventricular node (AV node)
- Electrical impulse flows through His bundle
- His bundle branches into left bundle branch (LBB) and right bundle branch (RBB)
- LBB and RBB further branch out
- LBB branches into the Left Purkinje fibres (LPF)
What do the nerves on the heart do (cardiac innervation)?
Modulate the conduction system only
Nerves on the heart can cause an increase/decrease in speed of heart rate
What does the fibrous skeleton do?
- Anchors the valves of the heart
- Gives atttachment to the cardiac musculature above and below
The fibrous skeleton is fibrous and acts as an electrical insulator. Ensures the electrical impulse can only travel through the His bundle from the atrium to the ventricle
Where does the blood supply of the heart come from?
Ascending aorta
- 2 branches of arteries from the ascending aorta
What are the arteries that supply blood to the heart called?
Left coronary artery: Back/left of ascending aorta
Right coronary artery: Front of ascending aorta
What does the left coronary artery divide into?
2 arteries
1. Circumflex branch
2. Anterior interventricular branch (supplies major muscular part of L. ventricle = if blocked = die = widow’s artery)
What is angina pectoris and what is the cause?
Pain in the chest, neck, left upper limb
Caused by the partial blockage of arteries = ↓ blood flow = some parts of the heart X get enough O2
What is myocardial infarction and what is the cause?
Basically a heart attack
Caused by a blocked artery = X blood flow = tissue death of parts of the heart
If happens gradually, there is a chance that some arteries that weren’t connected might interact = collateral arteries = provide alternate blood flow
What is angiogenesis?
Formation of new blood vessels from existing blood vessels
E.g. Formation of collateral arteries
What do balloon angioplasty and stents do?
Open up the blocked arteries
Balloon angioplasty = possibility of obstruction happening again
Stent = more permanent
What is a coronary artery bypass surgery?
Coronary artery bypass graft (CABG)
Uses a graft (blood vessel from elsewhere) and connects from the aorta, bypassing blocked artery to provide blood supply to part of the heart that was blocked
Characteristics of cardiac muscles (histology)?
- Striation
- Branching pattern (one cell connected to the other)
- Intercalated disc
What is the purpose of intercalated discs?
- Attaches one cardiac muscle to the neighbouring cardiac muscle
- When electrical activity reaches on cardiac muscle = spreads to other cardiac muscles = contract together = electromechanical coupling
What is the difference between skeletal muscles and cardiac muscles?
Cardiac muscles are striated BUT connected to each other (branching pattern)
Skeletal muscles are striated but separate
What are the parts of an artery and vein?
Tunica externa (fibrous tissue)
Tunica media (muscle & elastic fibre = flexibility of vessel)
Tunica intima (very delicate; endothelial cells here)
