Chp 3- Cardiovascular And Lymphatic System Flashcards
(87 cards)
1
Q
Pericardium
A
Fibrous protective sac enclosing heart
2
Q
Epicardium
A
Inner layer of pericardium
3
Q
Myocardium
A
Heart muscle, the major portion of the heart
4
Q
Endocardium
A
Smooth lining of the inner surface and cavities of the heart
5
Q
Right atrium
A
Receives blood from systemic circulation through superior and inferior vena cava
6
Q
Right ventricle
A
- Blood from RA
- pumps blood via pulmonary artery to lungs for oxygenation
- low pressure pulmonary pump
7
Q
Left atrium
A
-receives oxygenated blood from lungs+ 4 pulmonary veins
8
Q
Left ventricle
A
- blood from LA
- pumps blood to systemic circulation via aorta
- high pressure pump
- LV walls are thicker and stronger than RV
- forms most of the left side and apex of heart
9
Q
Atrioventricular valves
A
- Prevent backflow of the blood into atria during ventricular systole
- anchored by chordae tendineae to papillary muscles
- values close when ventricular walls contract
- Tricuspid and Bicuspid valves
10
Q
Tricuspid valves
A
Right heart valve
11
Q
Bicuspid valve
A
Left heart valve
12
Q
Semilunar Valves
A
- prevent backflow of blood from aorta and pulmonary arteries into ventricles during diastole
- pulmonary and aortic valves
13
Q
Pulmonary valve
A
Prevents right back flow
14
Q
Aortic valve
A
Prevents left backflow
15
Q
Systole
A
Period of ventricular contraction
16
Q
End systolic volume
A
Amount of blood in the ventricles after systole
-about 50mL
17
Q
Diastole
A
Period of ventricular relaxation and filing of blood
18
Q
End diastolic volume
A
Amount of blood in the ventricles after diastole
-about 120mL
19
Q
Atrial contraction
A
Occurs during the last third of diastole and completes ventricular filling
-compromises last 20-30% of end diastolic volume
20
Q
Coronary circulation
A
Blood circulates to myocardium during diastole
21
Q
Right coronary artery
A
Supplies:
- right atrium
- most of right ventricle
- inferior wall of left ventricle
- AV node and bundle of His
- SA node 60% of the time
22
Q
left coronary artery supplies?
A
- most of left ventricle
- has two divisions: left anterior descending and circumflex artery
23
Q
Left anterior descending artery (LAD) supplies?
A
- most of left ventricle
- interventricular septum
- inferior areas of the apex
24
Q
Circumflex artery supplies?
A
- lateral and inferior walls of the left ventricle
- portions of left atrium
- 40% of SA node
25
Where does coronary sinus receive blood from?
-receives venous blood from heart and empties into right atrium
26
Specialized conduction tissue
Allows rapid transmission electrical impulses throughout the myocardium
27
Where is the Sinoatrial (SA) node located?
-located at junction of superior vena cava and right atrium
28
What does the SA node do?
Main pacemaker of the heart, initiates the impulse rate of 60-100 bpm
29
What type of innervation does the SA node have?
Has sympathetic and parasympathetic innervation affecting both HR and strength of contraction
30
Where is the Atrioventricular (AV) node located?
At the junction of right atrium and right ventricle
31
What innervation does the AV node have and what is it's intrinsic firing rate?
- Parasympathetic and sympathetic
| - 40-60 bpm
32
What is Purkinje tissue and why is it important?
- specialized conducting tissue spread throughout the ventricles
- Right and left bundle branches of the AV node terminate here
- intrinsic firing rate of 20-40 bpm
33
Normal sinus rhythm originates where and what is the path it takes?
SA note--> impulse through both atria which contract together-->stimulates AV node-->transmitted down bundle of His to Purkinje fibers-->impulse spreads through both ventricles which contract together (atrial kick)
34
Muscle tissue
- striated muscle fibers with numerous mitochondria
- exhibits rhythmicity of contraction
- fibers contract as a functional unit
35
What type of muscle tissue is found in the walls of blood vessels?
Smooth muscle tissue
36
Define stroke volume and the normal range
- amount of blood ejected with each myocardial contraction
| - 55-100 mL/beat
37
What is stroke volume influenced by
-LV end diastolic volume= the amount of blood left in the ventricle at the end of diastole= preload
38
Define Frank-Starling law
The greater the amount of preload, the greater the quantity of blood pumped
39
Define afterload
The force the LV must generate during systole to overcome aortic pressure to open the aortic valve
40
Define cardiac output
Amount of blood discharged from the left or right ventricle per minute
41
What is the normal range of cardiac output
4-5 L per minute
42
How is cardiac output determined?
HRxSV=CO
43
How is cardiac index calculated and what is the normal range?
Cardiac index= CO/body surface area
| -2.5-3.5L/min
44
What is the normal range for left ventricular end diastolic pressure?
5-12 mmHg
45
Define ejection fraction
Percentage of blood emptied from the ventricle during systole
-clinically useful measure of LV function
46
How is EF calculated?
EF=SV/left ventricular end diastolic volume
47
What is the normal range of EF, and the consequences of low EF?
- lower EF= more impaired LV
| - >55%
48
Define atrial filling pressure
-the difference between the venous and atrial pressures
49
What happens to right atrial filling pressure during strong ventricular contractions?
- decreased pressure
| - enhanced atrial filling
50
What affects right atrial filling pressure?
- changes in intrathoracic pressure
- decreases during inspiration
- increases during coughing or forced expiration
51
When does venous return increase?
-when blood volume expands
52
When does venous return decrease?
-during hypovolemic shock
53
How is myocardial oxygen demand clinically measured?
HR x SBP= rate pressure produce
54
What is the job of arteries in peripheral circulation?
Transports oxygenated blood from areas of high pressure-->low pressure
55
What are arteries in peripheral circulation influenced by?
Elasticity and extensibility of vessel walls and by peripheral resistance
56
What are the function of arterioles?
Primary site of vascular resistance
57
What are capillaries?
Small blood vessels that connect the ends of arteries with the beginning of veins
58
What type of veins accompany arteries?
Deep veins
59
What is venous circulation influenced by?
- muscle contraction
- gravity
- respiration (increased return with inspiration)
- compliance of right heart
60
What is the job of the lymphatic system?
-drains lymph from bodily tissues and returns it to venous circulation
61
Lymphatic contraction occurs by:
1) parasympathetic, sympathetic, and sensory nerve stimulation
2) contraction of adjacent muscles
3) abdominal and thoracic cavity pressure changes during normal breathing
4) mechanical stimulation of dermal tissues
5) volume changes within each lymphatic vessel
62
Where is parasympathetic control located in the brain?
Medulla oblongata
63
parasympathetic stimulation occurs via which method?
Via the Vagus nerve and cardiac plexus
64
Where does parasympathetic innervation occur?
- innervates the SA node, AV node, and sparsely myocardium
| - releases Acetylcholine
65
What are the effects of parasympathetic stimulation on the heart?
- slows rate and force of myocardial contraction
- decreases myocardial metabolism
- causes coronary artery vasoconstriction
66
Sympathetic stimulation occurs via which method?
Cord segments T1-T4, upper thoracic to superior cervical chain ganglia
67
What does sympathetic stimulation innervate?
- SA node, AV node, conduction pathways, myocytes
| - releases epinephrine and norepinephrine
68
What does sympathetic stimulation cause?
- increase in rate and force of myocardial contraction and metabolism
- coronary artery vasodilation
69
What occurs when skin and peripheral vasculature receive sympathetic innervation?
-vasoconstriction of cutaneous arteries
70
What types of drugs increase sympathetic functioning?
Sympathomimetics
71
What types of drugs decrease sympathetic functioning?
Sympatholytics
72
What are baroreceptors?
Main mechanisms controlling heart rate
73
Where are baroreceptors located?
Walls of aortic arch and carotid sinus
74
Describe the process that occurs with circulatory reflex when BP increases.
Parasympathetic stimulation--> decreased rate and force of cardiac contraction--> sympathetic inhibition--> decreased peripheral resistance
75
Describe the process that occurs with circulatory reflex when BP decreases.
Sympathetic stimulation--> increased HR and BP and vasoconstriction of peripheral blood vessels
76
Where are chemoreceptors located?
Carotid body
77
What occurs when CO2 is increased, O2 is decreased, and pH levels are decreased?
Increased HR
78
What is hyperkalemia?
Increased concentration of potassium ions in the blood
79
What are the cardiovascular affects of hyperkalemia?
- decreases the rate and force of contraction
- produces widened PR interval and QRS
- tall T waves
80
Define Hypokalemia
Decreased concentrations of potassium ions
81
What are the effects of hypokalemia?
- flattened T waves
- prolonged PR and QT intervals
- produces arrhythmias which may progress to ventricular fibrillation
82
Define hypercalcemia and its affects on the cardiovascular system
Increased calcium concentration increases heart actions
83
Define hypocalcemia and its affects on the cardiovascular system
- decreased calcium concentrations
| - depresses heart actions
84
What can hypermagnesemia do to the cardiovascular system?
-lead to arrhythmias or cardiac arrest
85
What are the effects of hypomagnesemia
- ventricular arrhythmias
- coronary vasospasms
- sudden death
86
What are the effects of increased peripheral resistance?
-increases arterial blood volume and pressure
87
What is peripheral resistance influenced by?
Arterial blood volume- viscosity of blood and diameter of arterioles and capillaries
