F_Chapter 12: CARDIOVASCULAR SYSTEM: Flashcards
Anatomy of the Heart
SIZE, LOCATION, ORIENTATION (5)
- Size of a fist, weigh less than a pound
- Enclosed within the mediastinum
- Flanked on each side by the lungs
-
Apex points toward the left hip & lies in the 5
th intercostal rib - Base points toward the right shoulder & lies under the 2nd rib
The heart is enclosed by the ________a sac that is made up of three layers
What are the three layers?
Pericardium
- Fibrous Pericardium
- Serous Pericardium
3.
superficial part; protect the heart and anchors it to the surrounding structure
Layer of the Pericardium
Fibrous Pericardium
2 layers of Serous Pericardium
1. Parietal Pericardium – lines the interior of fibrous pericardium
2. Visceral Pericardium (Epicardium) – part of the heart wall; Innermost layer of pericardium and outermost layer of the heart wall
Produces lubricating serous fluid which collects in the pericardial cavity – between the serous layers
Layer of the pericardium
Serous Pericardium
Allows the heart to beat easily in a frictionless environment
Serous Pericardium
Three layers (walls) of the heart
- Epicardium
- Myocardium
- Endocardium
basically the visceral pericardium; outermost wall
Wall of the heart
Epicardium
consists of thick bundles of cardiac muscle twisted into ringlike arrangements; the layer that actually contracts
Myocardium
Fill in the blanks regarding Myocardium
o Myocardial cells are linked together by ____________
o Intercalated discs contain both ______ and _________
o ___________ allow ions to flow from cell to cell, carrying a wave of excitement across the heart
- Myocardial cells are linked together by intercalated discs
- Intercalated discs contain both desmosomes and gap junctions
- Gap Junctions allow ions to flow from cell to cell, carrying a wave of excitement across the heart
thin, glistening sheet of endothelium that lines the
heart chambers
Wall of the heart
Endocardium
The heart has 4 hollow cavities or chambers
* 2 ____ and 2 ____
Atria and Ventricles
These are the Receiving Chambers
What to Remember for this part?
Atria
NOT important in the pumping activity of the heart
* Main function of the atria is just to fill the ventricles with blood
The Discharging Chambers or actual pumps of the heart
What happens if it contracts?
What forms its apex?
Ventricles
- If ventricles contract, blood is propelled out of heart → Circulation
- Left Ventricle forms its apex
Divides the heart longitudinally
Part of the ventricle
Septum
The right side of the heart works as the? It also receives?
Pulmonary Circuit Pump
RECEIVES oxygen-poor blood from the veins of the body
Blood enters the heart from the ______ & ______
Which side of the heart?
Superior & Inferior Vena Cava
Right Side of the Heart
Blood enters the heart from the Superior & Inferior Vena Cava
▪ Pumps it through the ________ which splits into the left and
right __________
Which side of heart?
What do these arteries carrry?
▪ Pumps it through the **Pulmonary Trunk **which splits into the left and right Pulmonary Arteries
Right Side of Heart
▪ These** pulmonary arteries carry blood to the lungs**
Only function of pulmonary circulation is to
What is the process?
carry blood to the lungs for gas exchange and return it to the heart
PULMONARY CIRCULATION
→ Vena Cava
→ Right Atrium
→ Right Ventricle
→ Pulmonary Trunk
→Pulmonary Arteries
→ Lungs (capillary)
→ Pulmonary Veins
Left Atrium
The left side of the heart is responsible for ____________ circulation, which supplies oxygen- and nutrient-rich blood to ALL body organs
Systemic circulation
The left ventricle, which pumps blood over the entire body, have
substantially ________ walls than those of the right ventricle
Describe the difference between the walls
Thicker walls
Which is a much powerful pump?
Left ventricle (side) or right?
Left ventricle
Process of systematic circulation
Which side of the heart?
SYSTEMIC CIRCULATION
→ Pulmonary Veins
→ Left Atrium
→ Left Ventricle
→ Aorta
→ Systemic Arteries
→ Most body tissues (Capillary)
→ Systemic Veins
→ Vena Cava
→ Right Atrium
Left side of the heart
Allow blood to flow in only one direction through the chambers
What direction?
Heart Valves
There are 4 heart valves
Direction: From atria through ventricles and out the great arteries
Valves between the atria & ventricles
Main function?
Atrioventricular (AV) Valves
AV Valves prevent backflow into the atria when the ventricles contract
- the left AV Valve, consists of
two cusps of endocardium? - the right AV Valve, consists of 3 cusps?
- Bicuspid (Mitral) Valve
- Tricuspid Valve
anchor the cusps to the
walls of the ventricles
Found in AV valves
Chordae Tendineae (“Heart Strings”)
guards the bases ofthe two large arteries leaving the ventricular chambers
2 valves under this?
Semilunar (SL) Valves
(1) Pulmonary Semilunar Valve – has three cusps
(2) Aortic Semilunar Valve – has three cusps
When ventricles contract, the cusps of the semilunar valves _____
what action?
When ventricles contract, the cusps of the semilunar valves OPEN
The valve system maintains the ________ and prevents arterial blood from reentering the heart
one-way blood flow
True or False
Each set of valves operate at different times
True
AV Valves:
_____ [Heart Relaxation],
________ [Ventricle Contraction]
What action does the valves make?
AV Valves: OPEN [Heart Relaxation],
CLOSE [Ventricle Contraction]
SL Valves:
_____ [Heart Relaxation],
________ [Ventricle Contraction]
What action does the valves make
SL Valves:
CLOSED [Heart Relaxation],
OPEN [Ventricle Contraction]
The blood contained in the heart DOES NOT nourish the myocardium. The functional blood supply that oxygenates & nourishes the myocardium are the _______
Coronary Arteries
they branch from the base of the aorta andencircle the heart at the junction of the atria and ventricles
Coronary Arteries
What happens to coronary arteries when ventricles contract? When heart is relaxed?
Ventricles Contract: Coronary arteries are compressed (flow is inhibited, but not stopped completely)
Heart is Relaxed: Coronary Arteries are filled with blood
In one day, the heart pushes the body’s supply of 6 liters of blood through the vessels over ______ times. It pumps about _______ gallons of blood in a single day
1,000 times
It pumps about 1,500 gallons of blood in a single day
True or False
Cardiac muscles can beat independently and spontaneously
True
Cardiac muscles can beat independently and spontaneously even if all nervous connections are severed
Muscle cells in different areas of the heart have different _____
Without some unifying control system, the heart would be an _________
rhythm
Without some unifying control system, the heart would be an uncoordinated and inefficient pump
these muscle Cells in the heart beat about 60 times per minute
Atrial cells
these muscle Cells in the heart beat about 20-40 times per minute
Ventricular Cells
2 SYSTEMS THAT REGULATE HEART ACTIVITY
- Autonomic Nervous System
- Intrinsic Conduction system (Nodal System)
A system that regulate heart activity: increase and decrease heart rate
Autonomic Nervous System
A system that regulate heart activity: built into the heart tissue and sets its basic rhythm
Intrinsic Conduction System (Nodal System)
Composed of special tissue found somewhere else in the body
A system that regulates heart activity
INTRINSIC (NODAL) CONDUCTION SYSTEM
The tissue in the INTRINSIC (NODAL) CONDUCTION SYSTEM is a mix between
Tissue is a mix between muscular and nervous
Intrinsic Conduction System causes the heart muscle ________ to occur in ONLY __________ – from _____ to ______
Causes the heart muscle depolarization to occur in ONLY ONE DIRECTION – from atria to ventricles
Enforces a contraction rate of approximately 75 beats per minute on the heart – coordinated beats
INTRINSIC (NODAL) CONDUCTION SYSTEM
Most important part of Nodal System. These are tiny cell mass located in the right atrium, has the fastest rate of depolarization in the whole system. It starts each heartbeat and sets the pace for the whole heart
SINOATRIAL (SA) NODE
Direction of Nerve Impulse Generation (Depolarization) of the INTRINSIC (NODAL) CONDUCTION SYSTEM
(1) SA Node
→ (2) AV Node
→ (3) Atria Contract
→ (4) AV Bundle
→ (5) Purkinje Fibers
→ (6) Ventricles Contract
a rapid heart rate (over 100 beats per minute)
Name of the condition
Tachycardia
is a heart rate that is substantially slower than normal (less than 60 beats per minute)
Name of the condition
Bradycardia
Neither Tachycardia nor Bradycaria is pathological, but prolonged tachycardia may progress _______
fibrillation
heart contraction (ventricles)
Cardiac cycle and heart sound
Systole
heart relaxation (ventricles)
Cardiac cycle and heart sound
Diastole
refers to the events of one complete heartbeat,during which both atria and ventricles contract and then relax;
length is about ____ seconds?
Cardiac Cycle
length is about 0.8 seconds
Heart sounds are often described as ___ and ____
“lub” and “dub”
Heart sounds
Firstheartsound (Lub) is caused by the ________; longer and louder
closing of the AV
Heart Sound
Second Heart Sound (Dub) occurs when the ____________ at the end of ventricular systole
Semilunar valves close
Cardiac cycle phases
- Atrial diastole (ventricular filling)
- Atrial systole
- Isovolumetric contraction
- Ventricular systole (ejection phase)
- Isovulumetric relaxation
Forms the Vascular System
Blood vessels
contain blood that moves away from the heart
Blood vessels
Arteries
are smaller arteries, in which it then feeds into the
capillaries
Arterioles
are smaller veins, in which they receive the blood from the capillaries
Venules
receive blood from venules, which then finally feeds it into the great veins entering the heart – Venae Cavae
Blood vessels
Veins
Only the _________ directly serve the needs of the body cells
Blood vessels
Arteries and veins are just _____?
CAPILLARIES
just paths
TUNICS OF THE BLOOD VESSELS
- TUNICA INTIMA
- TUNICA MEDIA
- TUNICA EXTERNA
What tunic?
Lines the lumen (interior)
Thin layer of endothelium (Squamous Epithelial Cells)
Tunica Intima
What tunic?
Resting on a basement membrane (Areolar Connective Tissue)
▪ Function: surface decreases friction as blood flows through lumen
Tunica Intima
What tunic?
Middle layer
▪ Made up of mostly smooth muscle and elastic fibers
Tunica Media
What tunic?
What tunic?
Function:
✓ Active in changing the diameter of the vessels
✓ It constrict or dilates → changes blood pressure (INC or DEC)
Tunica Media
What tunic?
▪ Composed largely of fibrous connective tissue
Tunica Externa
Outermost tunic
What tunic?
Function: support and protect the vessels
Tunica Externa
pressure the blood exerts against the inner walls of
the blood vessels
Blood Pressure
The force that keeps the blood circulating continuously even
between heartbeats
Blood pressure
Blood pressure follows a It follows a ________ wherein blood moves continuously from areas of high pressure to areas with low pressure
ALWAYS REMEMBER:
It follows a blood pressure gradient, wherein blood moves continuously from areas of high pressure to areas with low pressure
Highest pressure is in the
large arteries closest to the heart and continues to drop throughout the systemic pathway – reaching zero at the right atrium.
Why are arteries thicker than veins?
Arteries are thicker than veins since there is higher pressure
Two arterial blood pressures are usually measured:
Systolic Pressure
and Diastolic Pressure
pressure in the arteries at the peak of ventricular contraction
Systolic Pressure
pressure when the ventricles are relaxing
Diastolic pressure
Blood pressure is reported in (units) and reported as (type of pressure)
- Reported in millimeters of mercury (mm Hg)
- Reported as Systolic Pressure/Diastolic pressure
Most common method of measuring blood pressure
Auscultatory Method,
an INDIRECT measurement which measure blood pressure in the brachial artery
Auscultatory Method
- Systolic pressure varies between ________ mm Hg
- Diastolic Pressure varies between _______ mm Hg
- Systolic pressure varies between 110 and 140 mm Hg
- Diastolic Pressure varies between 70 to 80 mm Hg
generally a systolic blood pressure below 100 mm Hg. Usually associated with long life and an old age free of illness.
Hypotension
normal response to fever, physical exertion and emotional upset. However, prolonged is pathologic.
Hypertension
Considered to be hypertension if BP is around _____ or higher
Considered to be hypertension if BP is around 140/90 or higher
Inflammation of the pericardium
Pericarditis
Pericarditis often results in a
decrease of serous fluid in the pericardial cavity
Causes pericardial layers to rub, bind, and stick to each other
Pericarditis
As they stick, they form painful adhesions that interfere with heart
movement
Pericarditis
Valve cusps become stiff
* Caused by _______
Valvular Stenosis
Valve cusps become stiff
* Caused by repeated bacterial infection of the endocardium
Bacterial infection of the endocardium is also known as
In what imbalance is this seen?
endocarditis
Valvular Stenosis
Forces the heart to contract more vigorously than normal to create
enough pressure to drive blood through the narrowed valve
What are its consequences?
Valvular Stenosis
- Consequences: Heart’s workload increases → heart weakens → fails
Under valvular stenosis faulty valve is replaced with a ____
What are the sources of this replacement?
synthetic valve
**Sources for valve replacement: **
- Cryopreserved human valve or
- from pigs’ heart (chemically treated)
Crushing chest pain
* Results when the myocardium is deprived of oxygen
ANGINA PECTORIS
Serves as a “warning” and should never be ignored
* If this is prolonged, oxygen-deprived heart cells may die → ____
Angina Pectoris
- If angina is prolonged, oxygen-deprived heart cells may die → infarct
What is the result of Angina Pectoris
The result is Myocardial Infarction (MI)
Other common names of Myocardial Infarction:
In what imbalance is this found?
✓ Heart Attack
✓ Coronary Artery Disease (CAD)
✓ Coronary Heart Disease (CHD)
✓ Acute Coronary Syndrome (ACS)
✓ Coronary Spasms
Angina Pectoris
Cause and Consequences of Heart Block
**Cause: **Any damage to the AV node
Consequence: block the ventricles from the control of the SA node
- The ventricles begin to beat at their own rate, which is much slower
What imbalance: Lack of an adequate blood supply to the heart muscle
* May lead to ________
Ischemia
May lead to fibrillation – a rapid, uncoordinated quivering of the
ventricles
a rapid, uncoordinated quivering of the ventricles; prevents the heart from pumping any blood and is a
major cause of death from heart attack
In what imbalance is this found
Fibrillation
Ischemia
One way to help a patient suffering from fibrillation is to use ________
In what imbalance is this found?
Automatic External Defibrillators (AEDs)
Ischemia
Abnormal or unusual heart sounds
* Fairly common in young children and some elderly people with
perfectly healthy hearts
What is considered part of pathologic demography?
Heart Murmurs
Those not included in 1st demographic (young children and some elderly p
- If a valve does not close tightly, a _________sound will be heard as the blood flows back through the partially open valve
- Distinct sounds can also be heard when blood flows through_________
In what imbalance is this found?
- If a valve does not close tightly, a “swishing” sound will be heard as the blood flows back through the partially open valve
- Distinct sounds can also be heard when blood flows through stenosed (narrowed) valves
Heart Murmurs
Common in people who stand for long periods of time, obese, or pregnant individuals
Varicose veins
Common factors that lead to Varicose veins
✓ Pooling of blood in the feet and legs
✓ Inactivity/Pressure on Veins → Inefficient venous return
a serious complication, in which it is the inflammation of a vein that results when a clot forms in a vessel with poor circulation
In what imbalance is this found?
Thrombophlebitis
Varicose veins
In Varicose Veins, all venous blood must pass through the pulmonary circulation; hence, it risks the person from having ________
Pulmonary Embolism
a temporary decrease in blood pressure resulting from the sudden rise from a reclining or sitting position
Orthostatic Hypotension
Type of Hypotension which may hint at poor nutrition and inadequate
levels of blood proteins
Chronic Hypotension
Type of Hypotension: one of the most important warnings of
Circulatory Shock
Acute Hypotension
is a condition in which the blood vessels are inadequately filled, and blood cannot circulate normally. The
most common cause is _______
Circulatory Shock
most common cause is blood loss
A common and dangerous disease that warns of increased peripheral resistance. Progresses without symptoms for the first 10 to 20 years
Chronic Hypertension
It slowly and surely strains the heart and damage the arteries. “Silent Killer”
Chronic Hypertension
Chronic Hypertion also ravages blood vessels, causing _____ and accelerates the progress of _______
Chronic Hypertension also ravages blood vessels, causing small tears and accelerates the progress of atherosclerosis
Accounts for ~90% of people with hypertension. This cannot attributed to any specific organic cause
Primary (essential) Hypertension
What factors are involved in Primary Hypertension?
diet, obesity, heredity, race, stress
More women than men are hypertensive. In what type of hypertension?
Primary (essential) hypertension
What type of hypertension?
More blacks than Caucasians are hypertensive
Child of hypertensive parents is twice as likely to develop high blood
pressure
Primary (essential) Hypertension
