Cardiovascular System Overview

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Questions and Answers

What is the primary function of the myocardium in the heart?

To regulate the heart's electrical conduction

To facilitate the pumping action of the heart (correct)

To protect the heart from infection

To provide structural support to the heart's chambers

Which structure separates the atria from the ventricles?

The aorta

The pericardium

The septum (correct)

The vena cava

During which phase of the heart's cycle do the atrioventricular valves open?

Ventricular contraction (systole)

Atrial contraction

Electrical conduction phase

Heart's filling phase (diastole) (correct)

What type of blood does the right atrium receive?

Deoxygenated blood from the body Signup and view all the answers

What is the role of the semilunar valves in the heart?

To separate the ventricles from the major arteries Signup and view all the answers

What is the primary factor that determines cardiac output (CO)?

The amount of blood ejected in one minute Signup and view all the answers

What does preload refer to in the context of heart function?

The amount of blood in the ventricles before contraction Signup and view all the answers

Which of the following conditions is commonly associated with aging in the cardiovascular system?

Stiffening of arteries Signup and view all the answers

What is the primary function of the venous system?

To return deoxygenated blood back to the heart Signup and view all the answers

What mechanism aids venous return in the circulatory system?

Contraction of skeletal muscles Signup and view all the answers

What characterizes the arteries in the peripheral vascular system?

They are elastic and muscular Signup and view all the answers

Which vessel connects the deep and superficial venous systems?

Perforators Signup and view all the answers

What is a significant consequence of arterial obstruction?

Ischemia to the tissue supplied by the artery Signup and view all the answers

What does a 4+ pulse amplitude indicate?

Bounding pulse Signup and view all the answers

What is the expected time for color to return to the feet after dangling them?

10 seconds or less Signup and view all the answers

Which of the following conditions is associated with venous overload?

Right heart failure Signup and view all the answers

What does pitting edema grade 3+ indicate?

Deep pitting Signup and view all the answers

During the assessment for arterial deficits, what observation would indicate arterial insufficiency?

Color becomes paler Signup and view all the answers

Which of the following pulse locations is NOT assessed bilaterally?

Femoral vein Signup and view all the answers

What does the presence of arrhythmias like atrial fibrillation indicate?

Potential heart dysfunction Signup and view all the answers

What does a 1+ pitting edema signify?

Mild pitting Signup and view all the answers

What is one of the primary functions of the lymphatic system?

Conserves plasma proteins Signup and view all the answers

Which of the following conditions could indicate a problem in the lymphatic system?

Swollen and tender lymph nodes Signup and view all the answers

What should be assessed for dyspnea during a cardiac examination?

Symptoms during exertion Signup and view all the answers

Which of the following symptoms is associated with poor circulation to the lower extremities?

Cyanosis Signup and view all the answers

Which diagnostic tool is commonly used in cardiovascular disease assessment?

Electrocardiogram (EKG) Signup and view all the answers

What lifestyle habit is NOT mentioned as a risk factor for cardiovascular disease?

Physical inactivity Signup and view all the answers

What is a potential reason for pallor in the legs during a subjective assessment?

Decreased circulation Signup and view all the answers

Which observation would NOT be part of an objective cardiac assessment?

Fatigue levels Signup and view all the answers

What occurs during ventricular diastole?

Blood fills the ventricles from the atria. Signup and view all the answers

What heart sound corresponds with the closure of the AV valves?

S1 Signup and view all the answers

What happens during the 'atrial kick' of late diastole?

Atria contract to push additional blood into the ventricles. Signup and view all the answers

What is indicated by a split S2 heart sound?

Increased blood return in the right side during inspiration. Signup and view all the answers

What does the T wave represent in an electrocardiogram?

Repolarization of the ventricles. Signup and view all the answers

Which of the following statements about heart murmurs is true?

Murmurs can indicate valve stenosis or regurgitation. Signup and view all the answers

What role does the SA Node play in cardiac function?

Initiates the electrical impulse in the heart. Signup and view all the answers

What is the primary function of depolarization in the heart?

To stimulate the contraction of cardiac muscles. Signup and view all the answers

What is a common cause for S3 heart sound?

Ventricular overload during early diastole. Signup and view all the answers

What is a key characteristic of the PR interval on an ECG?

Time taken for impulse to travel from atria to ventricles. Signup and view all the answers

Study Notes

Cardiovascular System Location

The heart is located in the mediastinum, between the 2nd and 5th intercostal space, from the right sternal border to the left midclavicular line
Precordium refers to the area over the heart

Heart Wall

The heart is surrounded by the fibrous pericardium, which protects the heart
The pericardium has two layers: parietal and visceral (epicardium)
Pericardial fluid is located between the layers, allowing for friction-free movement of the heart

Heart Wall Layers

Myocardium is the muscular wall of the heart, responsible for pumping action, and has a high oxygen demand
Endocardium is the layer of endothelial tissue lining the inner surface of heart chambers

Heart Chambers

The heart has four chambers: two atria and two ventricles
The chambers are separated by valves and a septum
Atria receive blood from major blood vessels and pump it into the ventricles
- The right atrium receives unoxygenated blood from the body through the superior and inferior vena cava
- The left atrium receives oxygenated blood from the lungs through the pulmonary veins
Ventricles receive blood from atria and eject it into vessels leaving the heart
- The right ventricle pumps unoxygenated blood to the lungs via the pulmonary artery
- The left ventricle pumps oxygenated blood to the body via the aorta

Heart Valves

Heart valves are unidirectional in a healthy heart, preventing backflow of blood
Atrioventricular valves (AV) separate atria and ventricles
- Tricuspid valve is on the right
- Mitral (bicuspid) valve is on the left
- They open during heart filling (diastole) and close with ventricular contraction (systole)
Semilunar valves (SL) separate ventricles from arteries
- Pulmonic valve is on the right
- Aortic valve is on the left
- They open during ventricular contraction/rising pressure within ventricles (systole) and close with ventricular relaxation

Cardiac Cycle

Ventricular filling/Diastole:
- Ventricles relax and fill with blood
- Early diastole: blood rushes into ventricles from atria through AV valves (75% ventricular volume)
- Late diastole: atrial kick (contraction of atria) pushes the last blood into ventricles (25% ventricular volume)
Ventricular Systole:
- Ventricular pressure rises higher than atrial pressure, closing AV valves (S1 sound)
- Ventricles contract, forcing blood into pulmonary and systemic circulation through open SL valves
- Ventricular pressure falls, closing SL valves (S2 sound)

Heart Sounds

S1: Closure of AV valves, beginning of systole, loudest at the apex of the heart
S2: Closure of semilunar valves, end of systole, loudest at the base of the heart
Split S2: during inspiration right side venous return increases, delaying pulmonic valve closure; left side blood return decreases, hastening aortic valve closure

Extra Heart Sounds

S3: Heard right after S2, early diastole, due to vibrations caused by ventricular overload
S4: Heard just before S1, end of diastole, due to blood pushed by atrial kick into a non-compliant ventricle

Murmurs

Turbulent blood flow due to increased velocity, decreased viscosity, valve defects, or unusual openings in heart chambers
Stenosis: narrowing of a valve
Regurgitation: incompetent valve

Electrical Conduction System

SA Node: initiates electrical impulse (pacemaker)
Impulse travels to atria
AV Node: slows conduction slightly to allow atrial contraction
Impulse travels through Bundle of His, bundle branches, and Purkinje fibers to ventricles

Electrical Impulse Conduction Terms

Depolarization: spread of electrical current, causes contraction (systole)
Repolarization: cells return to negative charge, heart at rest (diastole)
Diastole: heart chambers are at rest
Systole: pumping of the heart (mostly refers to ventricles)

ECG Interpretation

P wave: atrial depolarization
PR interval: time for impulse to travel from atria to ventricles
QRS complex: ventricular depolarization
T wave: ventricular repolarization

Cardiac Output

Amount of blood ejected per minute
Usually 4-6 liters per minute
Calculated as stroke volume x heart rate

Preload

Amount of blood available to flow into ventricles during diastole (venous return)
Represents ventricular stretching before contraction

Afterload

Pressure the heart must push against during ventricular contraction (systole)

Carotid Artery

Carries blood directly from the aorta to the head (brain)
Located in the groove between the trachea and sternomastoid muscle

Jugular Veins

Carry unoxygenated blood directly into the superior vena cava
Indicate pressures on the right side of the heart

Hemodynamic Changes with Aging

Stiffening of arteries causes increased systolic blood pressure
Increased left ventricular size
Increased pulse pressure (diastolic stays the same, systolic increases due to increased afterload)
Decreased ability of heart to increase cardiac output with exercise and stress
Increased risk of dysrhythmias and cardiovascular disease

Peripheral Vascular System

Arteries: carry oxygen-rich blood to the system
- Arterial walls are strong, elastic, and contain smooth muscle
- Pulse is generated due to expanding and recoiling of arteries with pressure wave
- Obstruction causes ischemia to tissues below
Veins: carry deoxygenated blood back to the heart
- Low pressure system
- Venous return depends on: contraction of skeletal muscles, intraluminal valves, and pressure changes with respiration
- Thinner walls, can dilate to accommodate greater volume

Arterial Pulses

Palpable when artery lies close to body surface
- Brachial, radial, ulnar, femoral, popliteal, dorsalis pedis, posterior tibial

Veins

Deep veins (e.g. femoral and popliteal): carry 90% of venous return from lower extremities
Superficial veins (e.g. great and small saphenous): most susceptible to stasis
Perforators: connect deep and superficial veins

Lymphatic System

Extensive vascular network that drains lymph from tissues and returns it to venous circulation
Functions: conserves plasma proteins, plays a major role in immune system, lipid absorption from intestine

Lymph Nodes

Important in the immune system
Cells within nodes engulf debris and bacteria, producing an antigen response
Swelling and tenderness of nodes indicates local inflammation
Only superficial nodes are accessible for examination
Generally not palpable in healthy adults

Subjective Assessment (Cardiac)

Chest pain: COLDSPA acronym used for assessment
Dyspnea:
- Exertion (DOE): dyspnea with exertion
- PND: dyspnea awakening from sleep
- Orthopnea: dyspnea when lying down
Cough: productive or non-productive
Fatigue
Cyanosis or pallor
Edema: swelling equal bilaterally or unilateral, disappears after rest
Nocturia: excessive urination at night

Subjective Assessment (Cardiac)

History of:
- Cardiovascular disease: heart attack, CHF, arrhythmias, valvular problems
- Family history of cardiovascular disease: heart attack or stroke before age 50
Diagnostics: EKG, cardiac catheterization
Cardiac surgery

Subjective Assessment (Cardiac)

History of:
- Hypertension
- Diabetes
- Bacterial or viral infections

Subjective Assessment (Cardiac)

Personal health habits:
- Smoking
- Nutrition
- Exercise
- Alcohol/drug use
- Medications: prescription and over-the-counter

Subjective Assessment (Peripheral Vascular)

Circulation: cold, numbness, pallor in legs, hair loss, edema (bilateral or unilateral, claudication (pain with walking)
Skin changes: color, texture, venous bulging, sores (location)

Objective Assessment (Cardiac)

Inspection:
- Whole body for color
- Extremities for edema and color
- Periorbital edema
- Neck vessels:
  - JVD: jugular vein distention, assess with head elevated 30-45 degrees
  - Carotid arteries

Objective Assessment (Cardiac)

Palpation:
- Carotid artery: medial to sternomastoid muscle, gently! bilaterally
- Extremities: color, hair distribution, size, symmetry, swelling, venous pattern, rashes, scars, ulcers, superficial veins

Objective Assessment (Peripheral Vascular)

Pulses: bilaterally
- Radial, brachial, femoral, popliteal, dorsalis pedis, posterior tibial
- Use Doppler if needed
- Assess rate, rhythm, symmetry, and amplitude

Pulse Amplitude Grading

4+: bounding
3+: increased
2+: brisk, expected
1+: diminished, weaker than expected
0: absent, unable to palpate

Objective Assessment (Peripheral Vascular)

Lymph Nodes: bilaterally
- Epitrochlear
- Inguinal

Assessing Arterial Deficit in Lower Extremities

Raise legs 12 inches for 30 seconds, wiggle feet for 30 seconds
Observe for color change (should become paler)
Sit up and dangle legs, note time for color to return (should be 10 seconds or less)
Note time for superficial veins to fill (should be 15 seconds or less)
Extreme pallor and/or dark red-bluish color indicates arterial insufficiency

Objective Assessment (Peripheral Vascular)

Lower extremity:
- Sensation: check for arterial insufficiency and diabetic neuropathy
- Edema: press firmly and look for pitting (depression)
  - 1+: mild pitting
  - 2+: moderate pitting
  - 3+: deep pitting, leg appears swollen
  - 4+: very deep pitting, leg obviously swollen

Edema

Venous overload due to right heart failure, vein occlusion, lymphatic problems, fluid and electrolyte imbalance, or nutritional disturbances.

Abnormalities: Congestive Heart Failure

Inability of heart to effectively pump blood
Left-sided failure: pulmonary edema
Right-sided failure: distended neck veins, peripheral edema
Patients may have both left and right heart failure.

Abnormalities: Arrhythmias

Atrial fibrillation
Ventricular tachycardia
Ventricular fibrillation

Abnormalities: Valve Problems

Stenosis: narrowing of valve
Regurgitation: incompetent (leaky) valve

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Description

Explore the essential components of the cardiovascular system, including the heart's location, structure, and function. This quiz covers the heart walls, the layers, and the four heart chambers involved in blood circulation. Test your knowledge on the anatomy and physiology of the heart.