Transcript The Cardiovascular System

The Cardiovascular
System
Medical Terminology
Chapter 5
Word Parts
 cardi/o
= heart
 vascul/o = blood vessels
 -ar = pertaining to (same as –al, -ic,
-ac)
 cardiovascular = term for
pertaining to the heart and blood
vessels
 Word
Roots:
thromb/o = blood clot
 arteri/o = artery
 phleb/o = vein
 ven/o = vein
 ventricul/o = ventricle
 atri/o = atria, atrium
 Endo- = within
 ather/o = plaque; fatty substance
 angi/o = vessel

 heart,
blood vessels, blood =
major structures of the cardiovascular
system.
 This consists of arteries, veins,
venules, arterioles, capillaries.
Structure of the Heart
 peri/cardi/um
– the double-walled
sac around the heart.
 pericardial
fluid – the fluid between
the layers that prevents friction when
the heart beats.
 The
walls of the heart are made up
of three layers:
 epicardium – outside or external
layer of the heart (epi = upon).
 myocardium – the middle and
thickest of the three layers; consists
of the cardiac muscle.
 endocardium – the inner lining of
the heart; comes in contact w/blood
 coronary
– another word
pertaining to the heart.
 Examples of using:
 coronary arteries, coronary
bypass, having a “coronary”
The Heart Chambers
 atria,
atrium – the two upper
chambers of the heart, aka
 “receiving” chambers – all blood
vessels coming into the heart enter
here. A right and a left atrium.
 ventricles – the two lower
chambers; all vessels leaving the
heart emerge from these chambers.
Heart Valves
 tricuspid
valve – controls the
opening between the right atrium and
the right ventricle. Tricuspid means
‘having three points’.
 pulmonary valve – between the
right ventricle and the pulmonary
artery. Sometimes called the
“semilunar valve” – like a half moon.
 mitral
valve – also known as the
‘bicuspid’ valve; located between the
left atrium and the left ventricle.
Bicuspid means ‘having two points’.
 aortic valve – between the left
ventricle and the aorta.
Blood Supply
 The
myocardium is specialized muscle
that beats constantly and must have
a continuous supply of oxygen and
nutrients and prompt removal of
waste.
 coronary
arteries and veins –
supply the blood needs of the
myocardium. If this blood supply is
disrupted, the myocardium in the
affected area dies. This is known as
“myocardial infarction” or MI.
Two circulation systems:
 systemic circulation – blood flow to
all parts of the body except the lungs.
 pulmonary circulation – blood flow
between the heart and lungs.
(Pulmonary = lungs).
 arteries, capillaries, veins – three
major types of blood vessels in the
body.
 lumen
– the opening within these
vessels through which the blood
flows.
 arteries – large blood vessels that
carry blood away from the heart to all
regions of the body. The walls of the
arteries are composed of three
layers; this makes them both
muscular and elastic, so they can
expand and contract with the
pumping heart beat.
 aorta
– the largest of all arteries.
 arterioles – smaller, thinner
arteries; carry blood to the capillaries.
 capillaries – connect the arterial and
venous circulatory systems. Only one
epithelial cell in thickness; the
smallest vessels in the body.
 venules
– small veins that form to
form larger veins
 veins – large vessels that carry blood
from all parts of the body back to or
toward the heart.
Thromboses and Embolisms
 thrombosis
– abnormal condition of
having a blood clot in a vessel.
 thrombus – the blood clot attached
to the interior wall of a vein or artery.
 thrombotic occlusion – when the
thrombus blocks the lumen of an
artery or vein.
 embolus
– a foreign object, such as
a blood clot, air, gas, or tissue that is
circulating (moving) in the
bloodstream.
 embolism – the blockage of a vessel
by an embolus.
 What
is an aneurysm?
 An
aneurysm is a localized weak
spot or balloon-like enlargement of
the wall of an artery.
The Heartbeat
 To
pump blood effectively throughout
the body, the contraction and
relaxation (beating) of the heart must
occur in exactly the correct sequence.
 The rate and regularity is determined
by electrical impulses from nerves
that stimulate the myocardium.
 These
electrical impulses are
controlled by the:
 sinoatrial (S-A) node
 atrioventricular (A-V) node
 Bundle of His
S-A Node
 Located
in the posterior wall of the
right atrium near the entrance of the
superior vena cava.
 Because it establishes the basic
rhythm, it is called the natural
pacemaker of the heart.
 Electrical
impulses from the S-A node
start each wave of muscle contraction
in the heart.
 The impulse in the right atrium
spreads over the muscles of both
atria, causing them to contract
simultaneously.
 This contraction forces blood into the
ventricles.
A-V Node
 S-A
node impulses also travel to the
A-V node.
 Located near the interatrial septum.
 It transmits the impulses on to the
Bundle of His.
Bundle of His
 Named
for Wilhelm His, 19th century
physician.
 Located in interventricular septum
 Branches of the bundle of His carry
impulses to the right and left
ventricles and the Purkinje fibers.
Purkinje fibers
 Stimulation
of the Purkinje fibers
cause the ventricles to contract
simultaneously, forcing blood into the
aorta and pulmonary arteries.
Electrical Waves
 On
an electrocardiogram (ECG / EKG)
 P wave – due to the contraction of
the atria
 QRS complex – shows the
contraction of the ventricles, as the
atria relax.
 T wave – relaxation of ventricles
Heart Sounds
 Two
distinct sounds are heard:
 “lubb dupp”
 lubb = the tricuspid and mitral valves
closing
 dupp = shorter and higher pitched.
Caused by closing of the aortic and
pulmonary valves
Arrhythmias (or dysrhythmias)
 An
irregularity or the loss of a normal
rhythm of the heart beat.
 Bradycardia = slow heartbeat; less
than 60 beats per minute (bpm)
 Tachycardia = fast heartbeat;
greater than 100 bpm.
 Paroxysmal
tachycardia - sudden
onset of tachycardia.
 Flutter = atrial contractions are
rapid but regular. On an EKG, it
looks like a sawtooth pattern.
 Palpitation = a pounding or racing
heart with or without an irregular
rhythm.
 Fibrillation
– a rapid, random and
ineffective contractions of the heart.
 Is like a “quivering” movement
 Atrial fibrillation – atria beat faster
than ventricles, but can cause a very
rapid ventricular heartbeat.
 Ventricular fibrillation – life
threatening. Fatal unless reversed by
electrical “defibrillation”.
Pulse and Blood Pressure
 Pulse
= rhythmic expansion and
contraction of an artery produced by
the blood moving through the artery.
 Blood pressure = the measurement
of pressure exerted against the walls
of the vessels.
 Systolic
pressure = occurs when
the ventricles contract; is the highest
pressure against the walls of the
blood vessels.
 Diastolic pressure = occurs when
the ventricles relax. Is the lowest
pressure against the vessel walls.
 Blood pressure is recorded as systolic
over diastolic; is measured in mm of
mercury (Hg).
Word Practice
 card/itis
 inflammation
of the heart
 endo/card/itis
 inflammation of the inner layer of the
heart
 myo/card/itis
 inflammation of the myocardium
 peri/card/itis
 inflammation
of the pericardium
(surrounding the heart)
 mitral stenosis
 abnormal narrowing of mitral valve
 Note: when a valve does not function
properly, it may allow blood to flow
back into the heart chamber; the
sound of this is called a heart
murmur.
 arter/itis
 inflammation
of an artery
 poly/arter/itis
 inflammation of several arteries
 arterio/sclerosis
 hardening of the arteries
Pathology of the CV System
 Ischemia
= deficiency in blood
supply to an area
 ischemic heart disease –
inadequate blood supply to the heart,
causing a group of cardiac problems
 Angina
pectoris – sometimes
just called “angina”. Severe
episodes of spasmodic choking or
suffocating chest pain. Usually
due to interference with the
supply of oxygen to the
myocardium.
 myocardial
infarction – also known
as a heart attack or “MI”. Is the
occlusion (closing off) of a coronary
artery resulting in an infarct (tissue
necrosis, tissue death) of the affected
myocardium. This can impair the
heart’s ability to pump blood
throughout the body.
 coronary
artery disease (CAD) –
atherosclerosis of the coronary
arteries that may cause angina,
myocardial infarction, and sudden
death.
 congestive heart failure (CHF) –
heart is unable to pump enough
blood to meet the body’s needs for
oxygen. Fluid pooling in legs, ankles,
lungs. Kidneys also retain fluid.
 hypertension
– high blood pressure.
 Can be classified as primary or
essential, secondary (caused by a
kidney disorder or tumor on the
kidney), and malignant (sudden
onset, life-threatening).
Cholesterol Info
 cholesterol
– consists of lipids (fatty
substances) that travel in the blood in
packages called “lipoproteins”. It
becomes pathologic when present in
excessive amounts.
 Low-density lipoprotein (LDL) –
“bad” cholesterol. Contributes to
plaque build up in arteries.
 high-density
lipoprotein (HDL) –
“good” cholesterol. It carries
unneeded cholesterol back to the
liver for processing and does not
contribute to plaque buildup. It
actually “protects” our heart.
 triglycerides – combinations of fatty
acids that are also found normally in
the blood in limited quantities.
 Hyperlipidemia
– a general term for
high levels of cholesterol, triglycerides
and lipoproteins.
The Blood
 Composed
of 55% liquid plasma;
45% “formed elements”.
 Formed elements = red blood cells
(RBCs), white blood cells (WBCs), and
platelets.
Plasma
 91%
water; 9% proteins, including
clotting proteins.
 Straw-colored.
 Fibrinogen and prothrombin =
clotting proteins; important in clot
formation to control bleeding.
 Serum = plasma without clotting
proteins.
Erythr/o/cytes
 Red
blood cells
 Produced by red bone marrow
 Shaped like a doughnut
 Hemoglobin – iron-containing
pigment that transports oxygen
 Reticulocyte – immature RBC;
meshlike pattern of threads
 The
normal life of an RBC is about
120 days. After this, macrophages
in the spleen, liver and bone marrow
destroy RBCs that are no longer
useful.
Leuk/o/cytes
 White
blood cells
 Protect the body against invaders
such as bacteria
 Neutrophils – most prevalent WBC
that fight infection by “phagocytosis”
 This is the process of engulfing and
swallowing germs (phago = eat)
 On
a blood test, an elevated
neutrophil count indicates a bacterial
infection.
 Basophils – promote the inflammatory
response.
 An elevated basophil count may
indicate an allergic condition.
 Eosinophils
– increase in response to
an allergic reaction.
 Lymphocytes – formed in red bone
marrow, spleen, lymph nodes.
Protect the body against disease.
 Monocytes – protect body against
disease; an elevated count usually
indicates a chronic infection.
Thromb/o/cytes
 Platelets
 Smallest
of the formed elements
 Important in the clotting of blood.
 When a blood vessel is damaged,
platelets are activated.
 Once activated, they become sticky
and clump together and form a clot.
Blood Types
 Four
major types
 A, AB, B, O
 Based on the presence of the A
and/or B antigens on red blood cells.
 In type O, both antigens are missing.
 Blood has to be typed and crossmatched for a transfusion.
Donors and Recipients
A
can donate to A or AB, and can
receive from A or O only.
 B can donate to B or AB only, and
can receive from B or O only.
 AB = the universal recipient; can
donate to AB only, and can receive
from A, B, AB or O
O
= the universal donor; can donate
to A, B, AB, O, and can receive from
O only.
 Hematologist
= specializes in
diagnosing and treating diseases and
disorders of the blood and bloodforming tissues.
 Hemat/o = blood.
Rh Factor
 RBCs
also contain the Rh antigen
 Named for Rhesus monkeys where
they were first found
 Each individual is either positive or
negative for the Rh factor.
 About 85% of Americans are Rh +;
they have the Rh antigen.
 The
remaining 15% = Rh -.
 They do not have the Rh antigen.
 The Rh factor causes difficulties when
an Rh + infant is born to an Rh –
mother.
New Word Roots and Suffices
 angi/o
= blood vessel.
 phleb/o = vein.
 You already know arteri/o = artery.
 ech/o = ultrasound.
 -emia = blood or blood condition.
 -penia = decreased; lack of; too few
Blood Disorders
 erythro/cyt/osis
– abnormal
condition of red blood cells; it is an
abnormal increase in RBCs.
 thrombo/cyto/penia = abnormal
decrease of platelets (thrombocytes).
 leuko/penia – abnormal decrease of
WBCs (leukocytes)
 leukemia
– a malignancy
characterized by a progressive
increase of abnormal leukocytes.
 anemia – a disorder of lower than
normal levels of RBCs in the blood.
an- = without; -emia = blood
condition.
Diagnostic Procedures of the CV
System
 pulse
oximeter – placed on finger;
measures amount of oxygenated
blood in the circulatory system;
normal = 96-100%.
 angiography, angiocardiography,
phlebography – x-ray study of
vessels after injection of a contrast
medium. (-grams are the films).
 cardiac
catheterization – a
catheter is passed into a vein or
artery and guided into the heart. A
contrast medium is injected into the
catheter; the dye travels through the
heart and shows how well the heart is
working.
 echocardiography – use of
ultrasound of the heart to show the
structures and motion of the heart.
Result = echocardiogram.
Treatment Procedures
 Percutaneous
transluminal
coronary angioplasty (PTCA) –
also called balloon angioplasty. A
small balloon on the end of a catheter
is used to open a partially blocked
coronary artery by flattening the
plaque deposit; then the balloon is
deflated and the catheter removed.
 In
a similar technique, a stent is
implanted in a coronary artery to
provide support to the arterial wall to
prevent re-stenosis. (re-narrowing).
 The
expanded stent is presses plaque
against the artery wall, and the stent
stays expanded.
 atherectomy
– surgical removal of
plaque from the interior lining of an
artery.
 After the catheter and balloon are in
place, the balloon is inflated and a
cutting tool is used to shave off
pieces of the plaque buildup.
 endarterectomy
– (end =
within, arter = artery, -ectomy =
surgical removal).
 the surgical removal of the lining
of an artery that is clogged with
plaque.
 carotid
endarterectomy – the
surgical removal of the lining of a
portion of the carotid artery, leading
to the brain.
 The artery may be reinforced with a
piece of vein taken from the leg. This
procedure is done to reduce the risk
of stroke by ensuring the blood flow
to the brain.
 Coronary
artery bypass graft –
(CABG) – also known as bypass
surgery.
 It requires opening the chest
(sternotomy). A piece of vein from
the leg is implanted on the heart to
bypass a blockage in a coronary
artery to improve the flow of blood to
the heart.
 valvuloplasty
– or ‘valvoplasty’ –
surgical repair of heart valve; could
also mean surgical replacement of a
heart valve.
 pacemaker – an electronic device
that may be attached externally or
implanted under the skin, with
connections leading into the heart to
regulate the heartbeat. Usually for
bradycardia or atrial fibrillation.
 Defibrillation
or ‘cardioversion’.
 The use of electrical shock to restore
the heart’s normal rhythm.
 This can be performed externally as
an emergency procedure or a device
may be implanted to control severe
arrhythmias. These are called ICDs,
or internal (or implanted) cardiac
defibrillators.
 Cardiopulmonary
Resuscitation –
CPR. An emergency procedure for
life support consisting of artificial
respiration and manual external
cardiac compression.