Orientation Week Flashcards
1
Q
Peripheral Vascular Symptoms
A
- Diseases that involve arteries, veins, lymphatic
- Can be assessed via pulses
2
Q
Peripheral venous Insufficiency
A
- The body can’t get blood from the extremities back to the heart (DVT).
- Stasis ulceration, painless, occurs at ankle area or lower leg just above the medial malleolus
3
Q
Peripheral arterial insufficiency
A
- Intermittent claudication
- Decreased or absent pulses
- Pale color when elevated, red when lowered, cool temp.
- No or mild edema, thin shiny , loss hair over foot/toes, nail thickening.
- Ulceration on toes or areas of trauma on feet, painful ulcers, gangrene may develop, compression not used
4
Q
Asymptomatic Arterial Narrowing
A
- Asymptomatic
- Not presenting with any clinical problems
- May suffer from atherosclerotic plaques etc
5
Q
Symptomatic Arterial narrowing
A
- Predictable
- Relieved by rest
6
Q
Intermittent Claudication
A
- Pain in the leg muscles that occurs during exercise and is relieved by rest.
- Especially calf but if issue more proximal also thigh.
- Condition seen in peripheral arterial disease
7
Q
Critical Limb Ischaemia
A
- Increasingly severe symptoms
- Onset of symptoms with less exertion
- Pain at rest
8
Q
Claudication Distance
A
Distance pt can walk before onset of symptoms
9
Q
Acute Limb Ischaemia
A
- Complete Arterial Occlusion
- Present with 6 Ps
10
Q
What are the 6 P’s?
A
- pale
- pulseless
- painful
- paralysed
- paraesthetic
- perishing with cold
11
Q
Clarifying Symptoms
A
- Speed of onset
- Duration and frequency of symptoms
- Severity (1-10)
- Character of pain.
- How do they experience pain
- Radiation (where does pain go to)
- Has pain changed
- Associated symptoms (vomiting, collapsing, shortness of breath)
- Aggravating and relieving symptoms
- Effect on QofL (impact on family life, employment etc)
12
Q
Non-modifiable risk factors
A
- Age
- Ethnicity
- Sex
- Personal/Family History of CVD
- Low Birth Weight
13
Q
Modifiable risk factors
A
- Hypertension
- Hyperlipidaemia
- Diabetes
- Obesity
- Smoking
- Sedentary lifestyle
14
Q
Past Medical History
A
- Medical conditions
- Visits to the Dr
- Investigations
- Procedures
- Operations
- Any problems On-going/fully-resolved/managed by medication
15
Q
Diabetes
A
- Managing blood sugar is not everything, will only marginally lower CVD risk.
- Also have to look at cholesterol etc.
16
Q
What is the most common cause of secondary hypertension?
A
Renal Disease
17
Q
What is Hypertension?
A
- Abnormally high blood pressure
- Asymptomatic
- Affects heart, kidneys and other organs
18
Q
Primary hypertension
A
- No known cause
- Most common
19
Q
Secondary hypertension
A
High blood pressure caused by the effects of another disease (e.g., kidney disease)
20
Q
Hyperthyroidism
A
- A disorder caused by a thyroid gland that is faster than normal and overly productive
- Results in a rapid pulse, nervousness, and loss of weight
21
Q
Hypercholesterolaemia
A
Too much cholesterol in blood can lead to atherosclerosis
22
Q
What is a True allergy?
A
Any med that causes a rash, itching, swelling, or difficulty breathing, otherwise it is an adverse reaction
23
Q
List 5 Chest Pain Causes?
A
- Cardiovascular
- Respiratory - cancer, embolus
- Upper GI - oesophageal disease
- Musculoskeletal - trauma (broken rib)
- Other - Herpes Zoster
24
Q
Stable angina
A
- Chest pain or pressure precipitated by activities such as exercise or emotional stress which increase myocardial oxygen demand
- NOT an acute coronary syndrome
- Predictable in onset
- Reproducible
- Relieved by rest/GTN
25
Examples of Acute Coronary Syndromes
- Unstable Angina
| - Acute MI (NSTEMI & STEMI)
26
Coronary Artery Spasm
- Variant Angina
| - Occurs during rest, often at night
27
Costochondritis
An inflammation of the cartilage that connects a rib to the sternum
28
Angina
Narrowing of coronary arteries so that when heart rate increases there is not enough blood flow to meet the O2 demands of heart muscle
29
GTN
- Glyceryl Trinitrate Spray
| - Used as vasodilator for treatment of angina
30
Acute Myocardial Infarct
- Can differentiate from unstable angina through tests
- Blood test will show troponin release
- ECG have to look at ST elevation
31
Pericarditis
- Inflammation of pericardium
- Viral/MI/TB/uraemia/malignany etc
- Sharp/retrosternal pain
- Relieved by sitting forwards
32
Aortic Dissection
- Sudden and severe
- Tearing of the inside of the aorta causing deep pain
- Radiates to left shoulder/back
33
Dyspnoea
- Shortness of breath
- Acute, chronic or acute-on-chronic
- 2 types in cardiac failure: orthopnoea/PND
- Venous return is higher when lying down so get leaky pulmonary vessels resulting in fluid build up in lung tissues.
34
Orthopnoea
- Shortness of breath (dyspnea) from lying flat.
| - Relieved by patient being propped up in bed or sitting in a chair.
35
Paroxysmal Nocturnal dyspnoea
- Awakening from sleep with dyspnoea and needing to be upright to achieve comfort.
- Feel like they're suffocating.
36
Palpitations
- Feeling a heart-racing, pounding, or fluttering sensation in the chest
- Uncomfortable sensations in the chest related to cardiac arrhythmias, such as premature ventricular contractions (PVCs)
- Ask the pt to tap it out
37
Arrhythmia
- Abnormal heart rhythm
| - NOT all pts experience palpitations!
38
Extrasystoles
- Extra beats of the heart
- Ventricular or atrial
- Heart jumps or 'flutters'
39
Atrial fibrillation
- May be unnoticed
- Heart jumping about or racing
- Associated breathlessness
40
Supraventricular Tachycardia
- Heart racing or fluttering
| - Associated polyuria
41
Ventricular Tachycardia
- Heart racing or fluttering
- Associated breathlessness
- May be present as syncope rather than palpitations
- A very rapid heartbeat that begins within the ventricles
42
Dizziness and Syncope
- Postural hypotension
- Neurocardiogenic (vasovagal)
- Micturition syncope
- Cardiac arrhythmias
- Mechanical obstruction to cardiac output
43
Oedema
- Abnormal accumulation of fluid in interstitial spaces
| - Uni/Bilateral
44
Pitting oedema
Oedema thats demonstrated by applying pressure to the skin causing a lasting indentation.
45
Fatigue
- Lots of different causes
| - Side effect of beta blockers
46
Axillary Nodes
- Lymphatic drainage of breast and other structures superficial to the thoracic wall
47
Pec Major
- Clavicle, costal cartilage and sternum to intertubercular groove of humerus
- Shoulder flexion and adduction
48
Pec Minor
- Ribs 3, 4, 5 to the coracoid process
- Stabilises scapula
- Landmark for axillary artery and brachial plexus
49
Latissimus Dorsi
- Iliac Crest, lower thoracic and lumbar vertebral spines to humerus
- Shoulder extension and adduction
50
Serratus anterior
- Upper 8 ribs to medial border of scapula
| - Scapular protraction and rotation in shoulder abduction
51
Breast
- Mammary gland in females
- Glandular tissue in fibro-fatty stroma
- 16 or so ducts converging on nipple
- Lie opposite to ribs 2-6
- Tail extending into axilla
- Blood supply from axillary and internal thoracic arteries
- Lymph drainage to axillary and internal thoracic nodes
52
Tumour Spread
```
- Breast lymph drainage described in 3 levels of severity for tumour spread into the axillary nodes
Level 1: anterior or pectoral group
Level 2: central group
Level 3: Apical group
- Can also spread to internal nodes
```
53
Functions of thoracic wall
- Respiratory movements: ribs, costal cartilages and intercostal movements, diaphragm
- Protects major organs
- Connects neck to upper limbs and abdomen
54
Pump Handle Inspiration
Rib elevation to push the sternum up and forward to increase thoracic anteriorposterior diameter
55
Bucket Handle inspiration
When additional increase in lateral diameter by rib eversion is required during enforced inspiration
56
Intercostal Muscles
- Between ribs
- Raise the ribs in inspiration but some may act in forced expiration to help lower the ribs
- Intercostal neurovascular bundle at the lower edge of the rib (important for chest drain insertion)
57
Thoracic Inlet
- T1, 1st ribs and costal cartilages and manubrium
| - Slopes antero-inferiorly
58
Apex of lung
Extends upwards to the level of T1 and neck of 1st rib
59
Structures that cross 1st rib
- Brachial plexus
| - Subclavian artery and vein
60
Structures that pass through the thoracic inlet?
```
Pass between the thorax and the upper limb
From anterior to posterior:
-Subclavian vein
(scalenus anterior)
-Subclavian artery
-Inferior trunk of the brachial plexus
```
Pass between the thorax and neck
- Vessels that supply and drain the head and neck
- Trachea
- Oesophagus
- Nerves (right and left vagus, recurrent laryngeal, right and left phrenic nerves)
61
Thoracic outlet syndrome
- Compression of the neurovascular bundle as it exits the thoracic outlet
- Clincians call inlet the outlet as vessels move out of it
62
Dysplastic first rib
- Can cause chronic trauma to the subclavian artery resulting in dissection and aneurysm
- Trauma can then cause embolisation to the forearm
63
Thoracic Outlet
- Closed by diaphragm
- T12
- 12th and 11th ribs
- Costal cartilages of ribs 10, 9, 8 ,7
- Xiphoid cartilage
64
Structures passing through diaphragm
```
"I ATE 10 eggs at 12"
T8 caval opening:
-IVC
-Right phrenic nerve
T10 oesophageal opening:
-Oesophagus
-Vagal trunks
-Left gastric vessels
T12 aortic hiatus:
-Aorta
-Azygos vein
-Thoracic duct
```
65
Body Cavitities
Lined by serous membranes with miniscule layer of fluid, lubricated potential space, friction free
Parietal and visceral layer
Thorax:
- lungs and chest wall lined by pleura
- Heart surrounded by pericardium
Abdomen and pelvis lined by peritoneum
Allows movement, expansion, contraction of organs
66
Pleura
- Subdivided into mediastinal, diaphragmatic, costal and apex
- Extends all the way down to 10th rib
67
Costodiaphragmatic recess
- The lower area of the pleural cavity into which the lung expands on inspiration
- Potential space between lung and diaphragm
68
What happens when Pleura 'Turns the corner'?
Pleura turns the corner and reflects in relation to the rib landmarks 2, 4, 6, 8, 10, 12
69
4 corners of the heart
3rd Right Costal cartilage
2nd Left Costal Cartilage
6th Right Costal Cartilage
5th Left Interspace (apex)
70
Mediastinum
- Central compartment of the thoracic cavity.
- Structures in the midline of the thorax, between the left and right pleural cavitities.
- It contains the heart, the great vessels of the heart, esophagus, trachea, phrenic nerve, cardiac nerve, thoracic duct, thymus, and lymph nodes of the central chest.
71
Superior Mediastinum
- Lies between the inlet and the plane between the sternal angle and T4/5, behind manubrium
- Bifurcation of the pulmonary trunk is just inferior to the superior mediastinum
72
Inferior Mediastinum
- Lies inferior to the plane between the sternal angle and T4/5 and the thoracic outlet
- Has 2 subdivisions within:
1. Middle Mediastinum - contents of pericardium
2. Posterior Mediastinum - aorta, oesophagus, thoracic duct, azygos veins
- Sometimes the thymus in anterior mediastinum is counted as 3rd division
73
Anterior Mediastinum
Lies behind the manubrium and sternum, anterior to the superior mediastinum and the upper part of the inferior mediastinum
Contains the thymus, which is active in children and atrophies with age leaving fatty remnant
74
Middle Mediastinum
The pericardium and its contents
75
Posterior Mediastinum
Structures behind the heart and pericardium
- Azygos vein
- Thoracic duct
- Descending aorta
- Oesophagus
76
Pericardium
- Fibrous and serous layers
- Surround the heart so that it can move, expand and contract
- Supports and stabilises
- Double-layered serous membrane surrounding the heart
Fibrous pericardium is fused with diaphragm
77
Reflection
Turning point where visceral layer becomes parietal layer of pericardium
78
Middle mediastinum
Consists of the pericardium and heart
79
Fibrous Pericardium
- Defines the middle mediastinum
- Surrounds the heart and great vessels
- Closed sac (fixed volume) attached superiorly to the roots of the great vessels (apex).
- Attached inferiorly to the central tendon of the diaphragm (base of pericardium, not heart).
- The phrenic nerves lie on either side of the sac and provides its sensory innervation (referred pain to shoulder tip)
80
Cardiac Tamponade
- Acute compression of the heart caused by fluid accumulation in the pericardial cavity
- Can be due to pericarditis as inflammation can cause oedema or can bleed into sac causing excess fluid in the pericardial sac.
81
Serous Pericardium
- Parietal layer attached firmly to the internal surface of the fibrous layer.
- Visceral layer attached firmly to the surface of the heart.
- Both layers are continuous around the roots of the great vessels
- Small film of lubricating fluid between the visceral and parietal layers.
82
Pericardial sinuses (folds)
- Subdivisions of the Pericardial Sac formed by reflections of the serous pericardium around the Great Vessels
- Oblique and transverse
83
Oblique sinus
- Lies posterior to the heart
- Potential space behind the left atrium
- Venous end of cardiac tube has a number of branches which seperate and stretch out during development, dragging with it the pericardium.
84
Transverse Sinus
- Separates the great arteries and veins
- Between arterial (anterior) and venous (posterior) ends
Anterior - aorta and pulmonary trunk
Posterior - SVC and left auricular appendage of left atrium
85
Pulmonary circulation
- Right heart pumps deoxygenated blood to the lungs
| - Low pressure 12-16 mmHg
86
Systemic Circulation
- Left heart pumps oxygenated blood throughout the body systems
- High pressure 70-120 mmHg
87
Valve sequence
1. Beginning of diastole. Aortic and pulmonary valves closed. Blood flows into
2. Opening of atrio-ventricular (tricuspid and mitral) valves during early moments of diastole
3. Atrial contraction during final moments of diastole
4. Closure of atrioventricular valves (tricuspid and mitral) very soon after systole begins
5. Opening of aortic and pulmonary valves during systole
88
Route of blood
1. Into right atrium
2. Through tricuspid valve
3. Into right ventricle
4. Through Pulmonary valve
5. Into pulmonary trunk to lung
6. From lungs into left atrium
7. Through mitral valve to left ventricle
8. Through aortic valve to aorta and systemic circulation
89
Chambers of the heart
- Right side receives deoxygenated blood from IVC and SVC
| - Left side receives oxygenated blood from the pulmonary veins
90
Heart position
Lies against posterior structures, passes obliquely to anterior
91
Heart Surfaces and Borders
1. Anterior - sternocostal
2. Inferior - Diaphragmatic
3. Base - posterior surface
4. Right border
5. Left border
6. Apex
92
What makes up the Sternocostal surface?
- Anterior
- Right ventricle
- Also slightly right atrium and auricle and left ventricle and auricle
93
What makes up the Diaphragmatic surface?
- Inferior
| - Left and Right Ventricle
94
What makes up the Base?
- Posterior
| - Left Atrium
95
What makes up the Right Border?
Right atrium
96
What makes up the Left Border?
Left ventricle and left auricle
97
What makes up the Apex?
- Formed by the left ventricle
| - Palpable in the 5th left intercostal space, mid-clavicular line
98
Surface markings
4 corners of the heart
Lies slightly obliquely with apex to the left
- 3rd Right CC
- 2nd Left CC
- 6th Right CC
- 5th Intercostal space, mid-clavicular line
99
Cardiac and pericardial relations
- Pleura, lungs and phrenic nerves on either side
| - Oesphagus and descending thoracic aorta behind the base of the heart
100
Right of the mediastinum
- Related to the RA and veins
- Arch of the azygos vein joins the SVC
- Right phrenic follows path of SVC
- SVC, Arch of Azygos, RA, IVC
101
Left of the Mediastinum
- Related to the LV and arteries
- Left common carotid artery
- Left Subclavian artery
- Arch of aorta
- Thoracic aorta
- LV
- Left phrenic
102
Phrenic Nerves
- Arise from cervical nerves C3, 4, 5 (keeps the diaphragm alive)
- Enter the superior mediastinum between the venous and the arterial planes (posterior to the Brachiocephalic veins)
- Pass between the fibrous pericardium and the parietal pleura
- Both pass anterior to the hilum of each lung
103
Right phrenic nerve
- Related to veins
- Passes to the right side of the SVC
- Right atrium is anterior to the lung root
- Right side of IVC to underside of diaphragm (T8)
- Runs on the lateral side of the great veins (brachiocephalic, superior/inferior vena cava)
104
Left Phrenic Nerve
- Related to arteries, between Left common carotid and Left subclavian.
- Arch of aorta is anterior (and lateral) to vagus
- Anterior to the left lung root on pericardium over left ventricle
- Pierces left dome of diaphragm near the apex of the heart
105
Referred pain
- Right and left phrenic nerves refer pain to the shoulder tip
- Sole motor supply to the diaphragm
- Sensory from the central tendon of the diaphragm and its parietal pleura and underlying peritoneum.
- Sensory from the mediastinal parietal pleura
- Sensory from the pericardium
106
Lateral supraclavicular
- C3, 4
- Nerve supplies skin over shoulder, which is the C4 dermatome
- Therefore structures with a sensory supply via the phrenic may refer pain to the should tip
107
Pericardial Nerve Supply
- Phrenic nerves are branches of the cervical plexus
- Sensory supply to the fibrous and parietal pericardium, adjacent parietal pleura and motor supply to the whole diaphragm
- Pain from pericardium may be referred to skin over the shoulder tip
108
Myocardium
- Thick middle muscle layer of the heart
| - Syncitium is an organ where muscles work as a single unit
109
Myogenic contraction
A contraction of the heart without external stimulation from a nerve.
110
Endocardium
- Endothelium
- Lines chambers and valves
- Inner lining of the heart
111
Pericardium
- Simple squamous epithelium secretes serous fluid
| - A double-layered serous membrane that surrounds the heart
112
Blood route
- Right atrium receives deoxygenated blood from the body, sends it to the right ventricles and then to the lungs for oxygenation (pulmonary)
- Left atrium receives oxygenated blood from the lungs, sends it to the left ventricle and then to the body (systematic)
113
Right Atrium
- Receives deoxygenated blood from SVC, IVC, coronary sinus
- Blood leaves via the Tricuspid valve to the RV.
- Anterior wall is trabeculated.
- Posterior wall smooth
114
Coronary Sinus
Drains blood from heart muscle itself
115
Where is the Right Atrium Trabeculated?
Anterior wall trabeculated by musculi pectinati and crista terminalis
116
Where/ What is the Interatrial septum?
- Located on smooth posterior wall.
| - Fossa ovalis and limbus fossa ovalis located here
117
Nodes
- Sinu-atrial node close to the opening of the SVC
| - Atrioventricular node on septum between opening of coronary sinus and tricuspid valve
118
Crista Terminalis
- Vertical ridge that separates the smooth and rough right atrium.
- Musculi pectinali and auricle arise from it
119
Musculi Pectinati
- Muscular ridges that modify the interior of both auricles and a portion of the right atrial wall.
- Pass from the crista terminalis to the auricle.
- Provide some power of contraction without majorly thickening the cardiac wall
120
Fossa Ovalis
- Site of what was the foramen ovale in the embryo
| - Ridge surrounding the is the limbus fossa ovalis
121
Foramen ovale
Opening from the right to left atrium that allowed oxygenated blood coming from the mother to by-pass the non-functioning foetal lungs
122
Tricuspid valve
- Tricuspid faces anteriorly and medially.
- Opens to the right ventricle.
- Inflow tract is forwards and medially through tricuspid valve.
- Opens and closes due to blood pressure differences.
123
Right Ventricle
- Deoxygenated blood enters through tricuspid valve from right atrium.
- Passes out through the infundibulum and pulmonary trunk.
- Forms most of the sternocostal surface and some of the inferior surface
- Walls are trabeculated
124
Infundibulum
- Entrance from right ventricle to pulmonary trunk. Wall is smooth.
- Outflow tract upwards and backwards via smooth (laminar flow) infundibulum to pulmonary valve and trunk.
125
Right Ventricle trabeculated
- Trabeculae carneae
- 3 papillary muscles with chordae tendineae
- Septomarginal trabecula
126
Trabeculae Carneae
- Muscular ridges on the internal surface of the ventricles.
- Give power of contraction without taking up space.
- Give rise to papillary muscles
127
Chordae tendineae
Strands of fibrous connective tissue that extend from the papillary muscle to the flaps of the right and left AV valves just before the ventricles contract, the papillary muscles contract and these to pull against the flaps of the valves allowing them to close but preventing inversion
128
Papillary muscle
- Cone-like projections on the ventricular walls, to which the chordae tendineae are attached.
- 3 papillary muscles for 3 cusps in tricuspid valve. Only two in left ventricle.
- Each papillary sends chordae tendoneae to 2 cusps
129
Laminar flow
- Smooth steady flow
| - Promoted by smooth muscle (Infundibulum) at exit/outflow of ventricle
130
Active Competence
- Papillary muscles and chordae tendineae prevent cusp eversion during systole.
- Tricuspid valve
131
3 Cusps of tricuspid
- Anterior, posterior, septal
- Attached to the fibrous ring which is part of the fibrous skeleton of the heart
- Closes during ventricular contraction (systole) prevents back flow to the atrium
132
3 "watch-pocket" of Pulmonary Valve
- Right, left, anterior
- Opens during systole, Closes in diastole
- Due to blood pressure differences
- Passive competence
- Attached to fibrous ring which is part of the skeleton of the heart
133
Passive competence
No muscle contracting, its purely elastic recoil and blood pressure enabling the valves
134
Pulmonary Trunk
- Lies inferior to arch of aorta
- Linked to aorta via ligamentum arteriosum
- Divides to become left and right pulmonary arteries
135
Left Atrium
- Forms the base of the heart
- Oxygenated blood from the lungs enters via the upper and lower, right and left pulmonary veins (4)
- Outflow via bicuspid (mitral) valve
- Interarterial wall smooth, can have slight depression = fossa ovalis
- Long, tubular auricle visible on left cardiac border
- Posterior to left atrium are the oesophagus and descending thoracic aorta
136
Left Ventricle
- Thick walled, systemic pressure (70-120 mmHg)
- Left border
- Apex beat
- Inflow tract anteriorly through mitral valve towards the apex
- Outflow tract upwards and backwards, posterior to the pulmonary valve and trunk
- Circular in cross section because the interventricular wall bulges towards the right.
137
Where does the Aortic valve lie in relation to pulmonary valve?
Lies posterior to pulmonary valve
138
Aortic vestibule
Smooth upper walled part of the left ventricle; inferior to aortic valve
139
Mitral/Bicuspid Valve
- Closes during ventricular contraction (systole)
- Prevents backflow to left atrium
- 2 cusps (anterior, posterior) attached to the fibrous ring which is part of the skeleton of the heart
- Active competance
140
Aortic Valve
- 3 Semi-lunar cusps at the apex of the aortic vestibule (right, left and posterior)
- Attached to the fibrous ring which is part of the skeleton of the heart
- Closes during ventricular relaxation (diastole), prevents backflow from aorta to left ventricle
- Passive competance as no papillary muscles of chordae tendineae
141
Coronary Arteries
- During diastole the aortic valve is close allowing blood to arteries.
- When valve is open in systole, blocks coronary arteries so no blood exits.
142
Cardiac (fibrous) skeleton
- Supports valves and myocardium.
- Electrically separates atria and ventricles
- Atrioventricular bundle of his should be the only conduction and connection between them.
- Provides complete separation between atria and ventricles.
143
Systole
- Atria relax and fill with blood
- Ventricle contract forcing blood upwards and backwards
- Simultaneously the mitral and tricuspid valves close.
- This is the 1st heart sound at the start of systole.
- Forces blood through the aortic and pulmonary valves
144
Diastole
- Atrium contracts forcing blood through the mitral and tricuspid valves
- Ventricles relax and fill with blood
- Aortic and pulmonary valves closed by pressure of blood trying to come back under elastic recoil - 2nd heart sound at end of systole.
- Aortic sinuses fill and blood enters coronary arteries
145
Auscultation of valves
1. Tricuspid, flow anteriorly and medially, ie towards the left. Listen at 4th/5th intercostal space just left of sternum
2. Mitral, flow anteriorly and inferiorly towards the apex - listen at apex
3. Aortic, flow superiorly and to the right - listen at right 2nd intercostal space
4. Pulmonary, flow superiorly and towards the left - listen at left, 2nd intercostal space
146
Valves
- Lie in a line behind the sternum
| - Cant hear through the sternum though so clinically listen at auscultation points
147
Functions of CVS
- Delivery system
- Enables the bulk flow of materials
- Temperature regulation
- Homeostasis
- Host defence (immune system)
- Reproduction - blood inherent in male response
148
Pressure
- If central pressure of CVS drops, cant provide tissue with adequate blood flow.
- It is a self-contained system of fluid so have to keep blood level topped up to maintain pressure to ensure demand is met
149
Regulation and integration
- CNS integrate overall activity of CVS with the activity and functions of the respiratory and renal systems
- CNS controls autonomic nerves and hormones etc
- Sympathetic nervous system effects blood vessels and blood pressure/volume
- Both CNS and PNS can affect heart
- Kidneys are a primary way that we can regulate blood volume
150
Cardiovascular system
- Right hand side pumps blood through the pulmonary circulation
- Left hand side pumps blood though systemic circulation
- Same volume of blood is pumped around each system in the same amount of time
151
Describe the Heart Muscle?
- The wall of the left ventricle is more muscular than the right as is pumping blood all around a higher pressure system.
- Right hand side is pumping around a much smaller pulmonary system so less resistance from vessels
152
What is Microcirculation?
The flow of blood through the arerioles, capillaries, and venules that is the site of exchange of gases, nutrients, and waste products with the cells.
153
Parallel arrangement
- Allows the independent regulation of blood flow to different organs
- Adapts to the metabolic demands of the tissue
- Balancing act, make sure can redirect to an area that needs it more ie muscles when excercising, whilst ensuring that all the other areas still have an adequate supply.
154
High capacity system
Majority of the blood in systemic is held in the veins
155
High pressure system
The arterial system is regulatory and a resistance generator. The real function of systemic circulation occurs here - the delivery of nutrients
156
Normal path of blood flow
- Pulmonary and systemic circulation are individual but need to be linked
- Blood vessels vary in composition but all are lined by endothelial cells
157
Rate of blood
At rest there are 5 litres per minute flowing around each system
158
Blood vessels
- All have ability to expand to expand to accommodate increase in volume.
- All but the capillaries and venules have smooth muscle which gives them the ability to contract
159
Describe Arterioles?
Smallest diameter muscular walled arteries
160
Describe Precapillary sphincters?
Rings of smooth muscle which control entry of blood from arteriole into each capillary
161
Describe Capillaries?
- Smallest diameter blood vessel: simple tube, one cell thick, of flattened endothelial cells
- Allows for diffusion of nutrients, waste etc in/out tissues
162
Describe Venules?
Smallest diameter vessels which drain blood back to the larger true veins
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What does the heart pump have to overcome?
Generate enough pressure in ventricle to overcome the pressure in the aorta for blood to exit into systemic circulation
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What do Valves do?
- Open passively - no open/close mechanism
- All to do with pressures that flow across them
- Prevent backflow of blood
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Describe Atrioventricular (cuspid) valves?
- Tricuspid valve between right atrium and right ventricle
- Bicuspid (mitral) valve between left atrium and left ventricle
- Fairly flimsy
- Attached to chordae tendineae
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Describe Semilunar valves?
- Aortic valve between left ventricle and aorta
- Pulmonary valve between right ventricle and pulmonary trunk
- Both tricuspid
- More heavy duty as have to deal with more stress and heavy abrasion
- Smaller opening, higher pressure therefore more stress and abrasion
- Greater pressure means dont need chordae tendoneae to keep them closed
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What is a Echocardiology?
- Procedure studying heart motion
| - Use ultrasound technology, or high-frequency sound waves, to create a visual image of a patient's heart
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Describe Cardiac muscle?
- Branched cells
- Connected by desmosomes at the junction between cells (intercalated discs) which are strong cell-to-cell adhesion molecules
- Striated (actin and mysoin filaments)
- Smaller fibres with individual nucles (uninucleate)
- Electrical connection through gap junctions - allow passage of ions, so action potential can spread
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Describe Intercalated discs?
- Attachment sites between the transverse lines between cardiac muscle cells by desmosomes.
- These allow impulses to move from one cell to another and securely fasten the cells together
- Also contain gap junction that connect the cytoplasm to allow easy transfer of ions between cells
