Cardio Vascular system Flashcards
1
Q
What are two major signs of a heart attack?
A
Chest pain radiating up the left shoulder, and diaphoresis
2
Q
What is a normal blood pressure
A
120/80mmHg or less
3
Q
What is a normal heart rate
A
60-100 bpm
4
Q
What is the path of the pulmonary circuit and what side is it on
A
The right side circulates deoxygenated blood to the lungs and brings back deoxygenated blood from the body
5
Q
What is the path of the systemic circuit and what side is it on
A
The left side of the heart pumps oxygenated blood from the lungs to the heart than to the rest of the body
6
Q
How is CO2 released from the blood
A
When deoxygenated blood is pumped to the lungs by the right ventricle, it gets exhaled and the blood gets reoxygenated
7
Q
What type of chamber are the atria
A
Receiving
8
Q
What type of chamber are the ventricles
A
Pumpers
9
Q
What does the right atrium do
A
Receives blood returning from the body
10
Q
What does the left atrium do
A
Receives oxygenated blood from the lungs
11
Q
What does the right ventricle do
A
Pumps deoxygenated blood to the lungs
12
Q
What does the left ventricle do
A
Pumps oxygenated blood to the rest of the body
13
Q
In anatomy terms where is the heart
A
In the mediastinum between the 2nd-5th intercostal spaces.
on the superior surface of the diaphragm
2/3 of the heart is left of the midsternal line
posterior to sternum, anterior to spine
14
Q
What surface of the heart is the base and where does it point
A
The posterior surface
Points towards shoulder
15
Q
What comes from the base of the heart
A
The “great” vessels
16
Q
What are the “great” vessels
A
Aorta, Superior/inferior vena cava, and the pulmonary trunk
17
Q
What does the apex point to
A
the left hip
18
Q
where is the apical impulse and what is it
A
The apical impulse is where the pulse is most easily felt in the chest.
This is palpated in the 5th intercostal space, just below the left nipple
found in the “midclavicular” line
19
Q
How can wrong compressions be fatal
A
If compressions done too low xiphoid process can be broken and sever parts of the heart
compressions too low can also cause air to build in the stomach causing vomiting and possible asphyxiation due to vomit
20
Q
What is the pericardium
A
A double-walled sac that surrounds the heart; made up of two layers
21
Q
Which layer of the pericardium protects and anchors the heart and prevents overfilling
A
The superficial fibrous pericardium
22
Q
What lines the internal surface of the fibrous pericardium
A
parietal layer
23
Q
Which layer of the serous pericardium lay directly on the hear
A
the visceral layer (epicardium)
24
Q
What separates the 2 layers of the serous pericardium
A
The pericardial cavity
25
What is pericarditis
Inflammation of pericardium
26
what are complications of pericarditis
Roughens the membrane surfaces causing pericardial friction rub which is a creaking sound that can be heard by a stethoscope
27
What is pericarditis caused by
Bacterial infection, viral infection, and trauma
28
What is cardiac tamponade
When excess fluid leaks into pericardial space
29
What is a complication of cardiac tamponade
Interferes with hearts pumping ability
30
How is cardiac tamponade treated
Treated by removing excess fluid with a needle and syringe through a procedure called pericardiocentesis
31
What are the 3 layers of the heart wall ( in order)
Epicardium
Myocardium
Endocardium
32
What is the epicardium
It is the visceral layer of the serous pericardium
33
*What is the myocardium*
The layer of contractile cardiac muscle cells
34
What is the endocardium
The inner most layer that lines the heart chambers and covers cardiac skeleton of valves
35
What is the fossa ovalis
It is the remanent foramen Ovale of the fetal heart that should close 6 months after birth
36
What 3 veins empty into the right atrium
Superior vena cava
Inferior vena cava
coronary sinus
37
Where does the superior vena cava return blood from
Above the diaphragm
38
Where does the inferior vena cava return blood from
Below the diaphragm
39
Where does the coronary sinus return blood from
Coronary veins
40
What chambers make up most of the volume of the heart
The ventricles
41
Which chambers have thicker walls and why
The ventricles because they have to pump harder
42
What do heart valves do
Prevent unidirectional flow in the heart
43
When do heart valves open and close
In response to pressure changes
44
What are the two major types of valves
Atrioventricular (AV) and Semilunar (SL)
45
Where are av valves located
Between atria and ventricles
46
What type of valve is the right av valve
Tricuspid
47
What type of valve is the left av valve
Bicuspid/mitral
48
Where are the SL valves located
Between ventricles and major arteries
49
Where is the pulmonary semilunar valve
Between the right ventricle and the pulmonary trunk
50
Where is the aortic sl valve
Between the left ventricle and the aorta
51
What anchors AV valves to papillary muscles
The chordae tendineae
52
What do the papillary muscles do
hold valve flaps in closed position
stop flaps from everting back into atria
53
What are two conditions of the heart valves
incompetent valve(regurgitation
Valvular stenosis
54
What can cause blood to backflow (regurgitate) causing the heart to pump the same blood over and over again
Incompetent valves
55
What is it called when valves stiffen and constrict openings making the heart have to pump harder
Valvular stenosis
56
What is the pathway of the blood through the right side of the heart
SVC, IVC, and coronary sinus-> Right Atrium -> tricuspid valve-> right ventricle ->pulmonary SL valve -> pulmonary trunk-> pulmonary arteries-> lungs
57
Pathway of blood through the left side of the heart
Four pulmonary veins (from lungs) -> Left atrium -> Mitral valve-> Left ventricle -> Aortic sl valve -> Aorta-> systemic circulation
58
Which side ventricle wall is thicker
The left side is 3x thicker
59
Which ventricle receives most of the coronary blood supply
the left ventricle
60
Which coronary artery supplies most of the blood
The left
61
What are the two branches of the left coronary artery
The left intraventricular artery
Circumflex artery
62
What are the two branches of the right coronary artery
Right marginal artery
Posterior intraventricular artery
63
Where do all the coronary veins dump blood into
The coronary sinus
64
What is angina pectoris and what are the symptoms
It is chest pain caused by a lack of blood flow to the heart causing a lactic acid buildup
A person with angina is on the path to getting a heart attack
65
What is a myocardial infarction and what causes it
It is a heart attack
caused by prolonged coronary obstruction
areas of cell death caused by the coronary obstruction are replaced with non contractile tissue
66
What are features of myocardial tissue
Lots of mitochondria
short, striated, branched
has intercalated discs
67
What are intercalated discs
They are connecting junctions between cardiac cells that contain
gap junctions that allow ions to pass from cell to cell
this allows heart to be a *functional syncytium*, a single coordinated unit
68
What are some differences between cardiac and skeletal muscles
The heart relies almost exclusively on aerobic respiration
cardiac muscle cannot function without oxygen
Cardiac muscle is more adaptable to other fuel sources like lactic acid but must have oxygen present
69
Does the heart need the nervous system to beat
No the nervous system only tunes the rate of heart beats, the heart can beat by itself
70
What is the intrinsic conduction system
The process by which the heart contracts on its own
71
What is the sequence of excitation in the heart in order
Sinoatrial node-> atrioventricular node-> Bundle of His->Right and left bundle branches-> Purkinje fibers
72
What is the Sinoatrial node
This is the pacemaker of the heart in the right atrial wall
73
What does the atrioventricular node do
delays the impulse from SA node by .1 second to allow for for blood to fill ventricle before contraction
74
What do the right and left bundle branches do
carry impulse to apex
75
What is an arrhythmia
An irregular heart rhythm
76
What is fibrillation
Rapid, irregular contractions of the heart
77
What is the main complication associated with fibrillation
The heart begins a quiver like motion causing it to pump little to no blood
78
What are then two types of fibrillation and which one is worse
Atrial fibrillation is more manageable and common
ventricular fibrillation is fatal and serious
79
What is the treatment for fibrillation
Defibrillation stops heart and giving a "clean slate" for proper depolarizations to resume
80
What causes a heart block
A defective av node
81
Can ventricles beat fast enough on their own to sustain life
No they beat too slowly
82
What are treatments for a defective av node
An artificial pacemaker which recouples atria and ventricles
83
*What does the vagus nerve do to heart rate*
Carries parasympathetic signals to decrease heart rate
Inhibits SA and AV nodes
84
What stimulates the AV and SA nodes through the sympathetic trunk
The cardioacceleratory center
this increases rate and force of contractions
85
What are contractile muscle fibers
They are responsible for for pumping action and make up most of the heart
86
Steps involved in AP
1. Opens fast voltage gated Na+ ion channels(Na flows into cell)
2. also opens slow Ca+ channels
3. at +30 mv, Na + channels close but Ca channels remain open prolonging depolarization
4. after about 200 ms ca channels closed and K+ channels opened
5. K + repolarizes cell
87
Differences in AP of cardiac muscle and skeletal muscle
AP in skeletal muscle lasts 1-2 ms while cardiac 200ms
contract in skel is 15-100 ms while cardiac is over 200ms
88
*Does cardiac muscle or skeletal muscle have longer ap and contraction and why*
Cardiac muscle, so the heart can squeeze out as much blood as possible
89
What is ecg
It is an electrocardiograph which is a graphic reading of electrical activity in heart
90
how many leads do most ecg have
12
91
What are the main features of the ecg
P wave, QRS complex, and T wave
92
What is the P wave
The depolarization of the SA nodes and atria
93
What is the QRS complex
Ventricular depolarization and atrial repolarization
94
What is the t wave
Ventricular repolarization
95
What is a sign of cardiac ischemia
A depressed or elevated s-t segment
96
What is cardiac ischemia
Lack of blood flow to heart
97
What is diastole
Period of heart relaxation
97
What is systole
The period of heart contraction
98
What happens during ventricular diastole
When ventricle is relaxed, low pressure, 80% of blood flows passively from atria to ventricle
than during the atria systole the rest of the 20% is forced into the ventricle
99
What is end diastolic volume
How much blood each of your ventricles fill with at the end of ventricular diastole
100
What happens in the beginning of ventricular systole
Atria relax, ventricles begin to contract
Rising ventricular pressure causes AV valves to close
once volume in ventricles all valves close than volume remains constant than contraction continues
once ventricular pressure exceeds pressure in large arteries sl valves forced open
101
What is the normal pressure in the aorta
120mmHg
102
Where does the blood go during ventricular systole
Blood is pumped into the Aorta and Pulmonary Trunk
103
What on the ecg does ventricular systole represent
The t wave
104
What is the cardiac cycle and the order
It is the blood flow through the heart in one complete heartbeat
atrial systole and diastole -> ventricular systole and diastole ->
105
How long does the cardiac cycle last
around .8 seconds
106
What should you think when you see systole
Pump
107
What should you think when you see diastole
Refill
108
What is end systolic volume(ESV)
The amount of blood left in the ventricle after systole
109
What causes the sl valves to close and what does this cause
Ventricular pressure dropping causing back flow of blood from aorta and pulmonary trunk
Causes the second heart sound "dub"
110
Do you want ESV to be high or low
Low
111
DO you want EDV to be high or low
high
112
Which intercostal space is the base of the heart in
2nd
113
Which intercostal space is the apex in
5th
114
What is a heart murmur
Any abnormal heart sound due to blood hitting an obstruction
115
What do heart murmurs usually indicate
Valve problems
116
What sound is heard with a stenotic valve
A high pitched sound or clicking
117
What sound is heard in an incompetent valve
A swooshing sound due to backflow of blood
118
*What is cardiac output*
The amount of blood pumped through the heart every minute
119
What is the equation for Cardiac output
Heart rate * stroke volume
120
What is stroke volume
Volume of blood pumped by one ventricle in one heart beat
121
What is the normal cardiac output (include full equation
co= 5.25 liters per minute
HR= 75bpm
SV=70ml/beat
122
What is the maximal CO in the average person
4-5 times the regular CO ( around (20-25 L/min)
123
What is the maximal CO in a trained athlete
30-35 L/min
124
How is stroke volume calculated
EDV-ESV
125
What factors affect SV
Preload, contractility, afterload
126
What is preload
The amount ventricular myocardium stretches prior to contraction
127
Is it better to have bigger or smaller preload and why
bigger because the more the muscle stretches the stronger the contraction of the heart will be, the stretch also means that there will be more EDV since there is more blood entering the heart
128
What is Venous return
The amount of blood returning to the heart
129
What is the most important determinant of Preload
Venous return
130
What increases venous return
Slow heart beat and exercise
131
Why is venous return so influential on preload
Because the more blood filling the heart means the heart has to stretch more
132
How does venous return affect SV
Higher venous return raises EDV
raises EDV by filling the heart with more blood
133
What is contractility
The contractile strength at a given length
134
How does contractility affect SV
It lowers ESV
135
Is it better to have a bigger or smaller contractility
Bigger because the stronger contractions are the lower your esv will be
136
What does inotropic mean
Modifying the rate of muscle contractions
137
How does sympathetic epinephrine affect contractility
It stimulates increased Ca influx causing more cross bridge formations
138
How do positive inotropic agents affect contractility and what are some examples
They increase contractility
examples are epinephrine, high Ca levels, dobutamine
139
How do negative inotropic agents affect contractility and what are some examples
They lower contractility
examples are High k+ levels, Ca2+ channel blockers, beta blockers, acidosis
140
What is afterload
Back pressure exerted by arterial blood
141
What can increase afterload
Hypertension
142
Do you want a higher or lower afterload and why
Lower because higher afterload causes an increase in ESV because blood is harder to push through ventricles causing the blood to stay in ventricles
143
What do positive chronotropic factors do and what are examples
They increase heart rate
examples are epinephrine, dobutamine, atropine
144
What do negative chronotropic factors do and what are examples
Decrease heart rate
Acidosis, high K+ levels
drugs such as beta blockers, certain calcium channel blockers
145
Sympathetic elcits what response
Flight or flight (raised hr adrenaline etc)
146
Parasympathetic elicit what response
rest and digest
147
What does Norepinephrine binding to beta 1 receptors cause
increased HR, increased contractility
148
What does acetylcholine do
Hyperpolarizes Pacemaker cells causing K+ influx decreasing HR
Little to no effect on contractility
149
What does thyroxine do and how
Increases heart rate by increasing affectivness of Epinephrine and norepinephrine
150
Why is do people with hyperthyroidism usually have tachycardia
Because they have increased levels of thyroxine
151
Affect of Hypocalcimia
depresses heart
152
Affect of hypercalcimia
Increases HR and contractility
153
Hyperkalemia
Alters electrical activity which can lead to heart block and cardiac arrest
154
Hypokalemia
Results in feeble heart beat and arrhythmias
155
What are other factors of heart rate
Age, gender, exercise, Body temp
156
What age has the fastest heart rate
Fetus
157
Which gender tends to have higher HR
Females
158
How does exercise affect HR
Increases HR while exercising and decreases average HR
159
How does body temp affect HR
HR increases as body temp increases
