Chapter 18- Cardiovascular System Flashcards
Pulmonary Circuit
Any of the blood vessels that carry blood to and from the lungs
Concerned with the right side of the heart
Pulmonary arteries
Pump oxygen-poor blood from the right side of the heart to the lungs to oxygenate it
Later returns to the other side of the heart through the pulmonary veins
Pulmonary veins
Pump oxygenated blood from the lungs to the left side of the heart
Systemic circuit
Any of the blood vessels that carry blood to and from the body tissues
Devliering oxygenated blood to the tissues for exchange to occur
Aorta
OXYGENATED blood leaves the heart through aorta to go into body tissues
Pre and Post cava
Oxygen POOR returns to the heart through the precava and postcava
Path of the blood through the heart
Blood travels through all four chambers of the heart and both circuits continuously
Left- Systemic
Right- Pulmonic
Oxygenated blood (left- Systemic)
Travels through arteries to get to tissues
Through aorta
Deoxygenated blood (left- systemic)
Travels through veins to get back into the heart
through pre and post cava
Deoxygenated blood (right- pulmonary)
Arteries to get to lungs
Oxygenated blood (right- pulmonary)
Going to left
Veins to get back into the heart
The right side is low pressure. Why?
It is smaller
Just going to lungs and back
The left side is high pressure. Why?
Must generate more force/pressure because more distance is covered and requires more muscle tissue
Walls more thick
Propels blood all over
The heart is tipped where?
In the thoracic cavity
apex points to the left hip
Fibrous pericardium
Outermost portion
Fibrous tissue
Less flexible
Prevents heart from filling with too much blood
anchors heart in chest cavity
Protects heart
Bending blood vessels is like bending a hose
Serous Pericardium
Internal portion
Divides into visceral and parietal layers that form fluid filled sac around the heart
Movement to it prevents heart from rubbing against other organs/structures
Prevents rubbing away of heart walls
Layers of the heart wall
Epicardium- outermost
Myocardium- middle later
Epicardium- innermost layer
Epicardium
Visceral layer of pericardium
Myocardium
Contains cardiac muscle cells arranged in spiral bundles
The heart twists slightly as it contracts to pump blood
Propels more blood and increases force generated
Endocardium
Covers internal surfaces of the heart including the valves
Continuous with linings of major blood vessels entering and leaving the heart
A slippery slick fluid that lines the endocardium
2 Atria
Superior receiving chambers
Right atrium
Receives OXYGEN POOR blood from some part of the body
Blood enters via pre and post-cava, coronary sinus
Left atrium
Receives OXYGENATED blood from the lungs
Blood enters through pulmonary veins
Atrial features
- Pectinate muscle- increases contractile force of atrium without increasing the mass of the heart (Not the true muscle tissue responsible for generating force, just an add on)
- Auricles- Two ears sitting o the external surface of the heart (Increases the amount of blood being brought into the atrium/waiting room)
- Fossa ovalis- Indentation in the left atrium (new foramen ovale)
2 ventricles
Inferior pumping chambers
Right ventricle
Deoxygenated blood to lungs
Pulmonary trunk (artery)
Pumps from the heart to the lungs
FROM right ventricle
Left ventricle
Oxygenated blood to other tissues
Aorta
Pumps from heart to the rest of the body
FROM left ventricle
Ventricle features
- Trabeculae carnae- ridges of muscle that assist with the proper functioning of the heart valves
- papillary muscle- Assist in opening/closing the heart valves
2 heart valves
- Atrioventricular valves- prevents backflow of blood from the ventricles back into the atria
- Semilunar valves- Prevents backflow of blood from blood vessels into ventricles (each has 3 cusps)
Tricuspid valve (AV)
Right side
3 cusps
Bicuspid valve (AV)
Left side
2 cusps
Papillary muscles
Take up slack of chordae tendinae
Aortic semilunar valve
sits at the base of the aorta
Left ventricle pumps blood into the aorta
Pulmonary semilunar valve
Sits at the base of the pulmonary trunk/artery
Right ventricle pumps blood into the pulmonary trunk
Heart murmurs
dysfunctional heart valve(s)
Regurgitation of blood (where this occurs depends on which valve doesn’t work
Stenosis
Left side more problematic than the right
either congenital or develop later in life
Heart sound problems
Usually not dangerous, but can indicate other potentially dangerous heart conditions
Stenosis
Valves do not allow enough blood through the valve
Heart sounds
Normal- lub-dup
Heart murmur- Lub-whoosh-dup (whoosh- blood going backwards
“Innocent” murmurs
usually congenital
can disappear
“Abnormal” murmurs
Children- indicate congential heart disease (fixed w surgery)
Adults- Indicate acquired heart valve issues
Slow down the flow of blood because it’s going in the wrong direction
Treat by putting in an artificial valve
Blood Supply to the heart
Coronaries
Coronary circulation
Blood supply that provides heart tissue with nutrients
Left coronary artery
Supplies left side of the heart
Anterior interventricular artery- Supplies anterior walls of ventricles and the wall dividing the two
circumflex artery- supplies the left atrium and posterior left side