Cardiovascular system: Blood

Blood
 essence of life, uncontrolled loss of it can result in
death.
 Has magical qualities (ancient and modern)
 Blood has also thought to define our character and
emotions
Examples:
-Noble bloodline described as “blue blood”
-Criminals have “bad blood”
-Anger causes their blood to “boil”
-Fear makes it “curdle”.

Blood- is a type of connective tissue consisting of a liquid

matrix
containing cells and cell fragment. The total blood volume in
the average adult is about 4–5 L in females and 5–6 L in
Males.
 Blood makes up about 8% of the total weight of the
body.
 Blood performs many functions essential to life and
can reveal much about our health.
 Blood helps maintain homeostasis.
 bend or fold , decreasing its size & enabling to pass
FUNCTIONS OF BLOOD
easily through smaller blood vessels.
1. Transport of gases, nutrients, and waste products
 Life span : 120 days (M) 110 days (F).
2. Transport of processed molecules
(1/3rd of RBC) Hemoglobin- pigmented protein responsible
3. Transport of regulatory molecule
for color.
4. Regulation of pH and osmosis
The heme molecules transport oxygen
5. Maintenance of body temperature
Globin molecules transport carbon dioxide and nitric oxide.
6. Protection against foreign substances
Iron is required for oxygen transport.
7. Clot formation
Carbonic anhydrase is involved with the transport of carbon
Dioxide.
COMPOSITION OF BLOOD
(HCO3-):CO2 + H2O → H++ HCO3-
Plasma (55%) (liquid matrix)
 low oxygen levels= kidney produce erythropoietin
Formed Elements (45%) (cell fragments)
(EPO), which stimulates RBC production in Bone
marrow.
Plasma is a colloid which is a liquid containing suspended
 Worn-out RBCs are phagocytized by macrophages in
substances that do not settle out of solution.
the spleen or liver.
Plasma proteins include: albumin (58%), globulins (38%)
Bilirubin (yellow pigment)- normally taken up by the liver
fibrinogen (4%)
and released into the small intestine as part of the bile.
If the liver not functioning normally, or flow of bile from liver
Additional Info:
to SI is hindered, bilirubin builds up in the circulation and
Serum: fluid remaining in test tube after clot has formed; it is
produces Jaundice-Pigments give feces brown color yellow
plasma minus the clotting factors
color of urine.
Lymph (tissue fluid): is similar to the fluid component of
plasma minus the plasma proteins
WBC- spherical that lack hemoglobin
Hematocrit: % by volume of packed RBC after centrifugation
 protect body against invading micro-organism &
Men: 40-50% Women: 35-45%
other pathogens
-RBCs are 700 times more numerous than WBCs and 17
 remove dead cells and debris from the tissue by
times more numerous than platelets.
phagocytosis.
PRODUCTION OF FORMED ELEMENTS
Platelets- minute fragment of cells (thrombocytes) are cell
Hematopoiesis (hemato = blood & poiesis = making).
fragments pinched off from megakaryocytes in the red bone
 In the embryo and fetus, the formed elements are
marrow
produced in a number of locations.
 After birth, red bone marrow becomes the source of
PREVENTING BLOOD LOSS
the formed elements
Vascular spasm- Vasoconstriction of damaged blood vessels
Hemocytoblasts- or stem cell, where all formed elements are
reduces blood loss.
derived.
Example: Platelets release thromboxanes-derived from
Growth factors determine the types of formed derived from
prostaglandins & endothelial cells lining blood vessels release
the stem cells & how many formed elements are produced.
the peptide endothelin.
RBC- Normal RBCs are disk-like shaped, biconcave discs
containing hemoglobin and carbonic anhydrase.
Platelet Plug Formation- Platelets repair minor damage to
Greater surface area= easier for gases to move into & out of
blood vessels by forming platelet plugs.
the RBC.
■ In platelet adhesion, platelets bind to collagen in damaged  Type O blood has neither A nor B antigens and both
tissues. anti-A and anti-B antibodies.
■ In the platelet release reaction, platelets release chemicals Mismatching the ABO blood group can result in transfusion
that activate additional platelets. reactions.
■ In platelet aggregation, platelets bind to one another to form
platelet plug. Rh Blood Group
Platelets also release chemicals involved with coagulation  Rh-positive blood has Rh antigens
(blood clotting)- formation of a clot (a network of protein  Rh-negative blood does no Rh antigen
fibers called fibrin). Antibodies against the Rh antigens are produced when an Rh-
There are 3 steps in the clotting process: negative person is exposed to Rh-positive blood.
 activation of clotting factors by CT and chemicals, The Rh blood groups is responsible for hemolytic diseases of
resulting in the formation of prothrombinase. the newborn (the fetus is Rh-positive and the mother is Rh-
 conversion of prothrombin to thrombin by negative)
prothrombinase.
 conversion of fibrinogen to fibrin by thrombin. Tx : an injection of anti-Rh antibodies called anti-Rh gamma
globulin (RhoGAM) can be given to prevent HDN.
Most clotting factors are manufactured in the liver require Vit. Rh-women should receive RhoGAM before delivery, and
K for their synthesis. soon after delivery, miscarriage, or abortion.
Many of the chemical reaction of clot formation require These abs bind to and inactivate the fetal Rh antigens before
Calcium and the chemicals released from platelets. the mother’s IS can respond to the foreign antigens by
The clotting process can be severely impaired by low levels of producing her own anti-Rh abs.
Vit. K & Calcium
Low numbers of platelets or reduced synthesis of clotting DIAGNOSTIC TESTS
factors because of liver dysfunction. Type and Crossmatch: Blood typing determines the ABO and
Humans rely on 2 sources of Vit. K. (half comes from diet & Rh blood groups of a blood sample. A crossmatch tests for
other half from bacteria within large intestine) agglutination reactions between donor and recipient blood.
 AB fight and sometimes kill bacterial infections CBC :
(intestinal bacteria) = reduce Vit. K levels causing  Consists of RBC count (M/ul),
bleeding problems.  Hgb (grams of hgb per 100 ml of blood)
 Hct (% volume of RBCs) and WBC (M/ul).
Antithrombin and Heparin- Anticoagulant in the blood RBC : 4.6-6.2 M/ul (M)
prevent clot formation. 4.2-5.4 M/ul (F).
Fibrinolysis (clot breakdown) is accomplished by plasmin. Hgb : 14-18 g/100 ml of blood (M)
12-16 g/100 ml of blood (F)
Case: Idiopathic Thrombocytopenic Purpura- is a Hct : 40-52 % total blood volume (M)
condition in which a px makes an antibody that destroys his or 38-48 % total blood volume (F)
her own platelets. Bleeding time is prolonged & cause is WBC : 5,000-9,000 / ul of blood.
unknown. Splenectomy (the spleen is the site of platelet
destruction) & drug therapy w/ corticosteroids to discourage Differential WB count- determines the % of each type of
antibody synthesis are methods of treatment. WBC.
Purpura is also seen in other condition associated w/ low Neutrophils (60-70%)
platelet ct. such leukemia & drug reaction. Lymphocytes (20-25%)
Monocytes (3-8%)
BLOOD GROUPING Eosinophils (2-4%)
Blood loss during surgery or due to injury, patient can go into Basophils (0.5-1%)
shock and die unless RBCs are replaced to restore the blood’s
oxygen-carrying capacity. Diagnostic Tests
Transfusion = transfer of blood or blood components from Clotting: blood’s ability to clot can be assessed by the platelet
one individual to another. count and the prothrombin time measurement.
Infusion = introduction of fluid other than blood such as Platelet count : 250,000-400,000 /ul of blood.
saline or glucose solution into the blood. Prothrombin time : 9-12 seconds.
Transfusion reaction = characterized by clumping or rupture Prothrombin time- determined by adding thromboplastin to
of blood cells and clotting within blood vessels. whole plasma.
Agglutination = clumping of cells Thromboplastin chemical released from injured tissues that
Hemolysis = destruction or rupture of the RBCs. start the process of clotting.

BLOOD GROUPING Laboratory Tests

Blood groups are determined by antigens on the surface of red Antiglobulin test (Coombs test) – demonstrate whether the
blood cells. Antibodies can bind to red blood cell antigens, px’s erythro. are coated with antibody & is useful in
resulting in agglutination or hemolysis of red blood cells. determining the presence of antibodies in infants of Rh(-)
ABO blood Group : women or in px’s autoimmune hemolytic anemia.
 Type A blood has A antigens and anti-B antibody Bleeding time – the time it takes for a small puncture wound
 Type B blood has B antigen and anti-A antibody to stop bleeding. Normal Time is 8 mins- less. Prolonged w/
 Type AB blood has A and B antigens and no anti-A use of aspirin and in platelet disorder thrombocytopenia.
or anti-B antibodies Simplate an incision is made while constant pressure is
applied using a sphygmomanometer.
Erythrocyte sedimentation rate (sed rate or ESR) – speed Folate- deficiency Anemia- inadequate folate in the diet
at which erythro. settle out of plasma. Venous blood is result in reduction in cell division therefore reduce number of
collected, anticoagulant is added, & the bld. is placed in a tube RBC.
in a vertical position. The distance that the erythro. fall in a
given period of time is the sedimentation rate. The rate is Disorder of Blood Clotting
altered in dse. conditions such as infections, joint Hemophilia – excessive bleeding caused by a congenital
inflammation, & tumor, that inc. the immunoglobulin content (hereditary) lack of one of the protein subs. (factor VIII)
of bld. necessary for blood clotting. Although platelet ct. of
hemophiliac px is normal, there is a marked def. in plasma
Blood Chemistry- composition of materials dissolved or clotting factor (factor VIII), which results in a very prolonged
suspended in plasma (ex. glucose, urea nitrogen, bilirubin and coagulation time.
cholesterol) can be used to assess the functioning and status of Tx : administration of deficient factor.
the body’s systems. DISEASES OF WBC
Leukemia – group of red bone marrow cancers in which
Clinical Procedures abnormal white blood cells multiply uncontrollably.
Apheresis – separation of bld. into its parts. Performed to  acute (symptoms develop rapidly)
remove toxic subs. or autoantibodies from the bld. or to  chronic (symptoms may take years to develop)
harvest bld. cells. Ex: leukapheresis, plateletpheresis, &
plasmapheresis.
Autologous transfusion the collection & later reinfusion of a
px’s own (auto-means self) bld. or bld. components.
BM biopsy – a needle is introduced into the BM cavity, & a
small amt. of marrow is aspirated & examined under
microscope. This procedure is helpful in the dx of bld.
disorders such as anemia, cytopenias, & leukemia.
BM transplant – BM cells from donor whose tissue & bld.
cells closely match those of the recipient are infused into a px
w/leukemia or aplastic anemia. First, the px is given total-
body irradiation or aggressive chemotherapy to kill all Granulocytosis – abn. inc. in granulocytes in the blood in
diseased cells & much of the normal BM. The donor’s response to infection or inflammation of any type.
marrow is then intravenously infused into the px, & it Eosinophilia – inc. in eosinophilic granulocytes. seen in
repopulates the patient’s marrow space w/ normal cells. allergic rxn. (asthma) or parasitic infections (tapeworm,
Problems encountered subsequently maybe serious infection, pinworm).
graft vs host disease (immune reaction of the donor’s cells to Basophilia – is an inc. in basophilic granulocytes seen in
the recipients), and relapse of the original disease (such as certain types of leukemia.
leukemia) despite the tx. Mononucleosis – an infectious disease evidenced by
increased no. of lymphocytes & enlarged cervical LN, caused
by Epstein-Barr virus (EBV). Lymphadenitis is present w/
fever, fatigue, asthenia (weakness) and pharyngitis. Atypical
lymphocytes are present in the bld., liver (hepatomegaly), &
spleen (splenomegaly). Mononucleosis is usu. transmitted by
direct oral contact (salivary exchange during kissing) & As the Right Ventricle contracts to pump oxygen-poor blood
affects primarily young adults. No tx is necessary. AB are not through the Pulmonary Valve→ Pulmonary Artery, the
effective for self-limited viral illness. Rest & slow return to Tricuspid Valve stays shut, thus preventing blood from
normal activities is advised. pushing back into the Right Atrium.

DISEASES Of BONE MARROW CELLS

Multiple myeloma – malignant tumor of BM. This is a
progressive tumor of antibody-producing cells (called Plasma
cells). The malignant cells invade the BM & destroy bony
structures. The tumors cause overproduction of
immunoglobulins & Bence Jones protein, an immunoglobulin
fragment found in urine. Often, the condition leads to
osteolytic lesions, hypercalcemia, anemia, renal damage, &
increased susceptibility to infection.
Tx: analgesics, radiotherapy, palliative (relieving, not curing)
Doses of chemotherapy, & special orthopedic supports.

Cardiovascular System: Heart

HEART- a hollow, cone-shaped, muscular pump located
within the mediastinum of the thorax and resting upon the  The blood → lung capillaries from the Pulmonary
diaphragm. Artery- loses its large quantity of CO2 into lung
 The adult heart is shaped like a blunt cone and is tissue, and the CO2 is expelled.
approx. the size of a closed fist, with an average  Oxygen → lung capillarie and is brought back to the
mass of 250 g in females and 300 g in males. heart via the Pulmonary Valve.
 It is larger in physically active adults than in other
healthy adults less than a pound.
 Decrease in size at the age of 65

FUNCTION
1. Generating blood pressure
2. Routing blood.
3. Ensuring one-way blood flow.
4. Regulating blood supply.

Apex- the blunt, rounded point of the heart

Base the larger, flat part at the opposite end of the heart

The Heart consisting of 4 chambers:

2 upper chambers called Atria (sing: atrium)
2 lower chambers called Ventricles.

The right side of the heart pumps blood through the

Pulmonary Circulation, which carries blood to the lungs,
 Carbon dioxide diffuses from the blood to lungs
 Oxygen diffuses from the lungs to blood.
The Systemic Circulation- the left side of the heart delivers
oxygen and nutrients to all the remaining tissues of the body.

Oxygen – poor blood enters the heart through the 2 largest

veins in the body (Venae Cavae)
Venae Cavae bring oxygen-poor bld. that has passed through
all of the body to the right atrium. The newly oxygenated blood enters the Left Atrium- The
 Superior Vena Cavae- drains blood from the upper walls of it contracts to force blood through the Mitral Valve
portion of the body into the Left Ventricle.
 Inferior Vena Cavae- carries blood from the lower
part of the body. The Left Ventricle has the thickest walls of all 4 heart
Right Atrium- thin-walled upper right chamber of the heart. chambers (3x the thickness of the Right Ventricle). It must
It contracts to force bld through the Tricuspid Valve into pump blood w/ great force so that the blood travels through
Right Ventricle- which is the lower right chamber of the arteries to all parts of the body. The blood is pumped out of
heart. the Left Ventricle → Aortic Valve → AORTA.
The cusps of the Tricuspid Valve form a one-way passage= The Aortic Valve- prevents the return of Aortic blood to the
keep the blood flowing in only one direction. Left Ventricle once it has been pumped out.
 pumped by heart (75 gallons an hour & about 2000 gallons a
Interatrial Septum- separates the 2 upper chambers (atria) day).
Interventricular septum- a muscular wall that comes bet. Closure of the heart valves is associated with audible sounds,
the 2 lower chambers (ventricles). such as “lub, dub, lub, dub”
Valve = prevents the backflow of blood ensuring one-way
flow. Opened and closed by the pressure changes of the bld. The “lub” is associated w/ closure of the Tricuspid Valve &
in the heart chambers. Mitral Valve at the beginning of systole.
The “dub” with the closure of the Aortic Valve &
VALVES: Pulmonary Valve at the end of systole.
Atrioventricular valves = between atria & ventricles The “lub” is S1 and “dub” is the S2
Right = Tricuspid (3 cusps/flaps) Normal cycle of the heartbeat starts with the beginning of the
Left = Bicuspid or Mitral valve (2 cusps) systole.
They are attached to the inner walls of the heart by tendons Murmur- abnormal heart sound.
(chordae tendinae) connected to the papillary muscles.
the valve is closed= papillary muscles contract, pull the CONDUCTION SYSTEM OF THE HEART
tendons taut, & prevent the valve from everting. Sinoatrial Node- the pacemaker of the heart. The current of
electricity by the pacemaker contracts the walls of the atria to
Semilunar valve (SL) = “half-moon”, have 3 cusps. and force blood into the ventricles (ending diastole).
 between the Left Ventricle and Aorta Atrioventricular Node- posterior portion of the interatrial
 between the Right Ventricle and Pulmonary artery septum. Sends the excitation wave to atrioventricular bundle
(specialized muscle fibers). In interventricular septum, the
The heart wall is composed of 3 layers : bundle of His divides into (R) & (L) bundle branches, which
Endocardium- a smooth layer of endothelial cells that lines form the conduction myofibers- extend through the ventricle
the interior of the heart and the heart valves. walls and stimulate them to contract.
Myocardium- the middle, muscular layer of the heart wall
and is its thickest layer. Bundle of His- carry electric sig. from Av node to bundle
Pericardium- a fibrous and membranous sac surrounding the bran.
heart. Autorhythmic Cells- a specialized muscle cells that conducts
 Visceral pericardium adheres to the heart Ap‘s to time and synchronize action of the chamber
 Parietal pericardium lines the outer fibrous coat.
Bundle Branches = one of which supplies each ventricle
Parietal cavity (bet. visceral & parietal pericadia) normally where they branch into.
contains 10-15 ml of fluid, lubricates the membranes as the Purkinje Fibers = reflect up external walls of ventricles and
heart beats. simulate contraction of cardiac muscle cells as a unit. Extend
into papillary muscles as well.
PHYSIOLOGY OF THE HEART
2 phases of Heartbeat: Node- a compact mass of conducting cells.
Diastole (relaxation) - occurs when the ventricle walls relax Electrocardiogram- record used to detect these electrical
and blood flows → heart from the venae cavae and Pulmonary changes in heart muscle as the heart beats.
Valve. Normal ECG shows 5 waves (deflections) represent the
 The Tricuspid Valve and Mitral Valve OPEN as electrical changes as a wave of excitation spreads through the
blood passes from the right and left atria → heart. (P, QRS, and T waves)
ventricles. P wave- represents electrical activity of the SA node impulse
 The Pulmonary Valve and Aortic Valve CLOSED formation and the change in the electrical activity in the wall
of the atria (atrial depolarization).
Systole (contraction)- occurs next, as the walls of the right QRS wave- represents ventricular depolarization as electricity
and left ventricles contract to pump blood into the Pulmonary passes through the atrioventricular bundle and the ventricular
Artery and the Aorta. wall. This is the largest wave because the ventricle contains
 Tricuspid Valve and Mitral Valve CLOSED
preventing the flow of blood back into the atria.

This diastole-systole cardiac cycle occurs between 70 & 80

times/min (100,000 x a day). The heart pumps about 3 ounces
of blood with the contraction. 1min= about 5 quarts of blood

the most muscle.

T wave- represents ventricular repolarization, which is when
the ventricular wall relaxes and recovers from contraction.
 Cardiac Output = 70 cm3 x 70 bpm = 4900 cm3/min
Myocardial Infarction (Heart Attack) = elevation in the ST Ex. Approximately 5 liter/min (also the approximate volume
segment of ECG tracing. (anterior, inferior) of blood in the male adult body)

Characteristic Of The Normal ECG

 Measurement, Rhythm, Conduction, and Waveform
description
Measurements
Heart Rate = 60-100 bpm
Pulse Rate Interval : 0.12 – 0.20 sec.
QRS duration : 0.06 – 0.10 sec.
QT Interval (QTc < 0.40 sec.)

Causes of elevation of ST segments

 LBBB (Left Bundle Branch Block)
 Normal varients (athletic heart)
 Acute pericarditis

Causes of depression of ST seg.

 Myocardial ischemia
 Digoxin effect
 Ventricular hypertrophy
 Acute post. MI, pulmonary embolus
 LBBB (Left Bundle Branch Block)

Causes of tall T waves

 Hyperkalaemia
 Hyperacute Myocardial infarction
 LBBB (Left Bundle Branch Block)
Causes of flattened or inverted T waves
 Age, race, Hyperventilation, Anxiety
 LVH (Left Ventricular Hypertrophy), PE (Pulmonary
Embolism) Pericarditis, electrolyte imbalance.

Sympathetic nerves speed up the heart rate during conditions

of emotional stress or vigorous exercise.
Parasympathetic nerves slow the heart rate when the need
for extra pumping is past.

The cardiac cycle- events in one heartbeat Cardiac Reserve- number of times that the CO may incs.
3 phases to the heartbeat : relaxation, ventricular filling, above its resting value.
ventricular contraction  For the ave. person this is 4-5 x.
The 2 atria must contract as the ventricles relax. The  A well trained athletes may inc it 7-8x.
ventricles fill w/ bld. The ventricles then contract & empty, &  People with severe heart disease may have no
the atria relax. reserve.

Stroke Volume (SV) = is the volume of blood ejected from Regulation of SV

the Left Ventricle per contraction. It is, on average, 70 cm3 About 40-50 % of the bld. in the ventricle remains after the
Cardiac Output (CO) = is the volume of blood ejected from contraction (end systolic vol.). The R & L sides of the heart
the Left Ventricle per minute. must pump equal vol. regulated by 3 factors:

The average adult resting heart rate is approximately 70 beats 1. Preload stretching- cardiac muscles stretched before
per min. So, contraction- the force of contraction incs.
Cardiac Output = Stroke Volume x Heart Rate FRANK-STARLING’s LAW- the greater physical
exertion venous return= the atria & ventricles are
overfilled, & stretched brings about a more powerful
contraction= increasing SV. This applies up to about
160 b/min, when the ventricular “filling time” starts
to dec.
If one side of the heart over-ejects= other side of the
heart to do likewise on the following beat, so
balancing the output on both sides of the heart.
2. Contractility of the myocardium- can be inc or dec.
by inotropic agents. Improve calcium inflow in the
muscle fibers.
Positive agents include: sympathetic innervations, glucagon, abnormalities in the heart at birth.
epi., NE, raised extracellular calcium, digitalis. CoA (Coarctation of the aorta)
Negative agents include: sympathetic inhibition, anoxia, PDA (Patent ductus arteriosus) – a small duct (ductus
acidosis, anaesthetic (ex. Halothane), raised extracellular arteriosus) bet. the aorta and the pulmonary artery, which
potassium. normally closes soon after birth, remains open (patent).
3. Afterload- Raised BP= difficult for the heart to pump Septal Defects – small holes in the septa between the atria
bld. → arteries. SV decs., and more bld. remains in (ASD) or the ventricles (VSD).
the ventricles. ToF (Tetralogy of Fallot) – a congenital malformation of the
heart involving 4(tetra) distinct defects, named for Etienne
CARDIAC BLOOD SUPPLY Fallot, French physician who described it in 1888.
Coronary circulation- consists of 2 coronary arteries, R & The 4 defects are :
L , and supplies the cardiac muscle w/ oxygenated bld.  pulmonary artery stenosis
The bld. drains → Coronary Veins ( the great cardiac vein &  VSD (ventricular septal defect)
the middle cardiac vein)→ Coronary Sinus (w/c empties into  shift of the aorta to the right
the RA).  hypertrophy of the right ventricle

Blood Pressure- the force that the blood exerts on the arterial
walls. This pressure is measured by a device called a
sphygmomanometer.
BP is usually expressed as a fraction. The initial high pressure
is generated by the heart.
 Systolic BP is 120 mm Hg for ave. male
 Diastolic BP is 80 mm Hg for ave. male

Factors Affecting BP are:

 As CO inc., BP increases
 As bld. vol. inc., BP increases
Peripheral Resistance (friction bet bld. & vessel walls). This is
related to:
Blood vessel diameter: the smaller= the greater the pressure.
Blood Viscosity: the greater= the greater the pressure.
Blood vessel length
Note: A & B can be regulated by the Vasomotor Center
(autonomic) in the medulla in the brain.

PATHOLOGICAL CONDITIONS
Heart:
Arrhythmias – abnormal heart rhythms (dysrhythmias) Congestive Heart Failure – the heart is unable to pump its
Exmples: Heart Block (Atrioventricular Block)– failure of required amount of bld. (more bld. enters than leaves through
proper conduction of impulses through the AV node to the the arteries). Bld. accumulates in the lungs (left-sided heart
atrioventricular bundle (bundle of His). failure) causing Pulmonary Edema (fluid seeps out of
Flutter – rapid but regular contractions of atria or ventricles capillaries into the tiny air sacs of the lungs).
(heart rhythm may reach up to 300 beats /min.) Treatment: ACE inhibitors can improve the performance of
Fibrillation – rapid, random, ineffectual, and irregular the heart and its pumping activity.
contractions of the heart (350 beats or more /min.). A Left Ventricular Assist Device (LVAD) is a booster pump
Defibrillator – an electrical device applied in chest wall in implanted in the abdomen, with a cannula (tube) inserted into
order to restore normal heart rhythm. the left ventricle.
Cardioversion – when electric shock stops the heart and
reverses its abnormal rhythm. Coronary Heart Disease (CAD)- Disease of the arteries
Digoxin – drug used to convert fibrillation into regular surrounding the heart. Usually the result:
rhythm. Atherosclerosis (deposition of fatty compounds on the inner
Automatic Implantable Cardioverter/Defibrillator (Aicd) lining of the coronary arteries).
– a device than can now be implanted in the chest to sense Thrombotic occlusion (blocking of the coronary artery by a
arrhythmias and correct them. clot).
Radiofrequency catheter ablation (rfa) – is a non-surgical Ischemia (bld. flow is decreased or stopped entirely)
treatment used to treat arrhythmias, such as paroxysmal leading to death (necrosis) of a part of the myocardium.
(sharp, sudden spasms) tachycardia. Infarction- the area of dead myocardial tissue.
Cardiac Arrest – is the sudden and often unexpected Myocardial infarction (heart attack) severity depends on the
stoppage of heart movement, caused by heart block or size of the artery that is blocked and the extent of the
ventricular fibrillation (resulting from underlying heart blockage.
disease). Angina Pectoris- episode of chest pain. (precordial pain)
Palpitations – are uncomfortable sensations in the chest resulting from temporary difference bet. the supply and
associated with different types of arrhythmias. demand of oxygen to the heart muscle. Angina= result of low
The 2 cardiac causes of palpitations are : PVCs and PACs. O2 levels in the blood. restricted blood flow to the heart
(CAD), or an inc. in the work of the heart beyond normal
CONGENITAL HEART DISEASES levels.
 open and close normally. Mitral Stenosis, atrial fibrillation,
Treatment: Nitroglycerin Sublingual (acute attack). CHF, due to weakening of the myocardium.
Nitrates- a powerful vasodilator and muscle relaxant. Tx: reduced activity, drugs to control arrhythmia, surgery to
 Guidelines for CAD begin w/ controlling risk factors repair a damaged valve, and anticoagulant to prevent emboli.
such as smoking, obesity, and lack of exercise. Mechanical or porcine (pig) valve implants to replace
Daily Aspirin to prevent formation of clots deteriorated heart valves.
Hydroxymethylglutaryl-CoA- “statins” reduce the
production of cholesterol in the liver. MAJOR JONES CRITERIA FOR RHD
Erythema marginatum = macular skin lesion
After the occurrence of anMI, patients may require Sydenham chorea = neurological disorder with rapid,
maintenance and anti-ischemic therapy with drugs called involuntary, purposeless movements
beta-blockers, w/c reduce the force and speed of the Carditis = involves myocardium, endocardium & pericardium
heartbeat and lower BP. (pancarditis)
nitrates and calcium channel blockers, cause dilation of bld Subcutaneous nodules Polyarthritis = migratory large joint;
vessels= easier for the heart to pump through vessels. seen more in adults.

Surgical treatment of CAD= Open Heart Operation Called MINOR JONES CRITERIA FOR RHD
Coronary Artery Bypass Grafting (CABG).  Fever
Cardiologist perform Percutaneous Transluminal Coronary  Arthralgia
Angioplasty (PTCA)- catheterization with balloons and  Leukocytosis
stents opens clogged coronary arteries.
Transmyocardial Laser Revascularization (TMLR)- makes
holes in the heart muscle to induce angiogenesis.
Cardiovascular System: Blood Vessels
Gene therapy- giving DNA or viruses contain DNA to
promote expression of factors that lead to angiogenesis) is Circulatory System (CS)
another new technique to restore damaged heart muscle.  Pulmonary Vessel
Endocarditis – inflammation of the inner lining of the heart  Systemic vessels.
caused by bacterial endocarditis. This condition may be a The CS and Heart maintain sufficient blood flow to tissues.
complication of another infectious dse., an operation, or an
injury. Damage of the heart valves produces lesion called FUNCTION
vegetations (resemble cauliflower) that break off into the  carries blood
bldstream.  exchanges nutrients, waste products, & gases
 transport hormones
Emboli (material that travels through the bld.) lodge in the  regulates BP
small vessels of the skin, multiple pinpoint hges known as  directs blood flow.
petechiae (from Italian petechio, meaning a fleabite) form. STRUCTURAL FEATURES OF BLOOD VESSELS
Treatment : antibiotic.  Blood flows from the heart through elastic arteries
muscular arteries, and arterioles to the capillaries.
hypertensive heart disease – high BP affecting the heart.  Blood returns to the heart from the capillaries
Caused by the contraction of arterioles→ inc. pressure in through venules, small veins, and large veins.
arteries.
Mitral Valve Prolapse (MVP) – improper closure of the Except for capillaries and venules, blood vessels have 3 layers
mitral valve when the heart is pumping blood. :
Murmur – extra heart sound, heard between normal beats  Tunica Intima, the innermost layer, consists of
caused by a valvular defect or dse. disrupts the smooth flow of endothelium, a basement membrane, and CT.
bld. in the heart.  Tunica Media, the middle layer, contains circular
A bruit- abnormal sound or murmur heard on auscultation. smooth muscle and elastic fibers.
A thrill- vibration felt on palpation of the chest.
Pericarditis – inflammation of the pericardium. In most
instances, pericarditis is secondary to dse. elsewhere in the
body (such as pulmonary infection). Bacteria & viruses cause
the condition, or etio. may be idiopathic. Malaise, fever, and
chest pain occur, as well as accumulation of fluid within the
pericardial cavity.
Cardiac Tamponade- Compression of the heart due to
collection of fluid.
Tx : pericardiocentesis to drain the excess fluid.

Rheumatic Heart Disease – heart disease caused by

rheumatic fever. RF is a dse., (occurring in childhood) that
can follow a few wks. after a streptococcal infection. Damage
is done to the heart, particularly the heart valves, by one or
more attacks of RF. The valves, esp. the Mv, become
inflamed and scarred (with vegetations), so that they do not
  Tunica Adventitia, the outer layer, composed of CT. BLOOD VESSELS OF THE PULMONARY
CIRCULATION
Pulmonary Circulation- moves blood to and from the lungs.
Pulmonary Trunk- carries oxygen-poor blood heart→lungs
Pulmonary Veins carry oxygenated blood Lungs → Left
Ventri.

Blood Vessels of the Systemic Circulation: Arteries

Aorta leaves the LV to form the ascending aorta, the aortic
arch, and the descending aorta, which consists of the thoracic
aorta and the abdominal aorta.

Arteries of the Head and Neck:

The brachiocephalic (L common carotid, and L subclavian
arteries branch from aortic arch to supply the head & upper
limb
Aortic Arch: CCA (Common Carotid Artery) and the
Vertebral Arteries supply the head. Divide to form the ext.
carotids and the internal carotids.

ARTERIES OF THE UL:

Subclavian Artery ( axillary artery, brachial artery)= radial &
ulnar arteries.
Thoracic Aorta and its Branches:
 visceral branches = thoracic organs
 parietal branche=thoracic wall.
Abdominal Aorta and its Branches:
Arteries- Carry blood away from the heart. Largest to the  visceral branches= abdominal organs
smallest branches  parietal branches= abdominal wall.
 elastic arteries- largest artery, large elastic fiber but Arteries of the Pelvis:
little smooth m. in their wall. Branches of the internal iliac arteries supply the pelvis.
 muscular arteries have much smooth m. and some
elastic fibers, undergo vasodilation and Arteries of the LL:
vasoconstriction to control blood flow to different The common iliac arteries give rise to the ext. iliac arteries,
regions of the body.. and the ext. iliac artery continues as the femoral artery and
 Arterioles, the smallest arteries, have smooth m. then as the popliteal artery in the leg . The popliteal artery
cells and a few elastic fibers. They undergo divides to form the anterior and posterior tibial arteries.
vasodilation and vasoconstriction.
Capillaries- consist of only endothelium and are surrounded Blood Vessels of the SC: Veins
by a basement membrane & loose CT the adventitia,  The SVC drains the head, neck, thorax, and UL.
that contains pericapillary cells.  The IVC drains the abdomen, pelvis, and LL
 Nutrient and waste exchange
 Blood is supplied to capillaries by arterioles. Veins of the Head and Neck:
 Precapillary sphincters regulate blood flow through  Int. jugular veins drain the brain, anterior head, and
capillary networks. anterior neck.
VEINS  ext. jugular veins drains the posterior head and
 Venules are composed of endothelium surrounded posterior neck.
by a basement membrane. Small veins covered with Veins of the UL:
a layer of smooth m. and a layer of CT. deep veins= brachial, axillary, and subclavian
 Medium-sized and large veins= less smooth m. and Superficial veins= cephalic, basilic, and median cubital.
fewer elastic fibers than arteries of the same size.
 Vasa vasorum are blood vessels that supply the Veins of the Thorax:
tunica adventitia and tunica media. The L & R brachiocephalic veins and the azygos veins return
blood to the SVC.

Veins of the Abdomen and Pelvis:

 Posterior abdominal wall veins join azygos veins.
 Veins from the kidneys, adrenal glands, and gonads
directly enter the IVC.
 Veins from the stomach, intestines, spleen, and
pancreas connect with the hepatic portal vein-
transports blood to the liver for processing. The
hepatic veins from the liver join the IVC.

Veins of the LL:

  deep veins course with the deep arteries and have Ex. Approx 5 liter/min (also the approx vol. of bld. in the
similar names. male adult body)
 superficial veins are the great and small saphenous Chemoreceptor Reflex : sensitive to changes in blood O2,
veins. CO2, and pH. Located in the carotid bodies and the aortic
bodies.
PHYSIOLOGY OF CIRCULATION The CR increases PR in response to low O2 levels, high CO2
Blood Pressure: levels, and reduced blood pH.
 BP is a measure of the force exerted by blood against
the blood vessel walls. moves blood through vessels. HORMONAL MECHANISMS:
 can be measured by listening for korotkoff sounds kidney release renin in response to low BP.
produced as blood flows through arteries partially Renin promotes the production of angiotensin II, causes
constricted by a blood pressure cuff. vasoconstriction and increased secretion of aldosterone-
Pressure and Resistance: normal adult between 120 mmHg reduces urine output.
(systolic) and 80 mmHg (diastolic) in the aorta. ADH released from post. pituitary causes vasoconstriction
blood vessels constrict = blood flow increases and blood flow and reduces UO.
decreases. The HR releases atrial natriuretic hormone =atrial BP
increases.
Pulse Pressure: ANH- inc. in urine production= decrease in blood volume
PP is the difference between systolic & diastolic pressures. PP and BP.
increases when SV increases. Summary of Regulatory Mechanism:
 pulse can be detected when large arteries are near the  The baroreceptor, chemoreceptor and adrenal
body surface. medullary reflex mechanisms are most important in
Capillary Exchange: Most exchange across the wall of the short-term regulation of BP.
capillary occurs by diffusion, BP , capillary permeability, and  Hormonal mechanisms, such as the renin-
osmosis effect movement of fluid across the wall of the angiotensin-aldosterone system, ADH, and ANH, are
capillaries. There is a net movement of fluid from the blood more important in long-term regulation of BP.
into the tissues. The fluid gained by the tissues is removed by
the lymphatic system. EFFECTS OF AGING ON THE BLOOD VESSELS
Reduced elasticity and thickening of arterial walls result in
CONTROL OF BLOOD FLOW IN TISSUES HPN and decreased ability to respond to changes in BP.
Local Control of Blood Flow: Blood flow through a tissue is Atherosclerosis is an age-related condition.
usually proportional to the metabolic needs of the tissue and is  Efficiency of capillary exchange decreases with age.
controlled by the precapillary sphincters.  Walls of the veins thicken in some areas and dilate in
Nervous & Hormonal Control of Blood Flow: The others.
vasomotor center (sympathetic division) controls blood vessel  Thromboses, emboli, varicose veins, and
diameter. Other brain areas can excite or inhibit the vasomotor hemorrhoids are age-related conditions.
center.
Vasomotor tone- state of partial constriction of blood vessels. Aneurysm – local widening of an artery caused by weakness
The NS is responsible for routing the flow of blood, except in in the arterial wall or breakdown of the wall owing to
capillaries, and for maintaining BP. atherosclerosis. Occur most commonly in aorta.
Epinephrine and NE released by the adrenal medulla alter The danger is rupture because as the wall of the artery pushes
blood vessel diameter. outward it becomes progressively thinner.
Treatment: depends on vessels involved, site, and health of
Regulation of Arterial Pressure: Mean Arterial Pressure patient.
(MAP) is proportional to CO x the PR Hypertension – high blood pressure. Most high BP is
essential. In adults, a BP ≤ 140/90 mmHg is considered high.
Baroreceptor Reflex: sensitive to stretch. Treatment: diuretics, b-blockers, ACE inhibitors, & calcium
located in the carotid sinuses and the aortic arch. channel blocker, low salt & fat diet + stop smoking.
The BR changes PR, HR, and SV in response to changes in Secondary HPN= lesions, such as glomerulonephritis,
BP. pyelonephritis, or dse. in adrenal glands.
MAP is 100 mm Hg. Peripheral Vascular disease – blockage of bld. vessels
(arteries) in the lower extremities due to atherosclerosis.

MAP =
[ ( 2× D ) +S ] When arteries in the groin or upper leg narrow or become
blocked, bld. flow to the lower leg and foot is reduced.
3 Femoral & Popliteal artery are often involved. An early sign
Usual range : 70 – 110 mmHg of the problem is intermittent claudication (absence of pain or
Stroke Volume (SV) = ivolume of bld. ejected fr the LV per discomfort in a leg at rest, but pain, tension, and weakness
contraction. after walking has begun).
Average:70 cm3 Tx: exercise, avoidance of nicotine, w/c causes vessel
Cardiac Output (CO) = vol. of bld. ejected fr the LV per constriction, & control of risk factors such as HPN,
minute. hyperlipidemia & DM.
The ave. adult resting heart rate is approx 70 beats per min. Surgery include endarterectomy and bypass grafting (from
normal proximal vessel around the diseased area to a normal
CO = SV x HR vessel distantly).
CO = 70 cm3 x 70 b/min
= 4900 cm3/min
Raynaud Phenomenon – short episode of pallor and Magnetic Resonance Imaging (MRI)
numbness in the fingers and toes due to temporary Cardiac MRI – magnetic waves are beamed at the heart, &
constriction of arterioles in the skin. Condition is idiopathic, an image is produced.
but may also be secondary to some other, more serious
disorder. Episodes can be triggered by cold temp., emotional Other Procedures
distress, or cigarette smoking. Cardiac catheterization – a thin, flexible tube (catheter) is
Tx: protect body from cold & use of vasodilators. introduced into a vein or artery & is guided into the heart for
Varicose Veins – abnormally swollen and twisted veins, purposes of detecting pressures & patterns of bld. flow.
usually occurring in the legs. Conditions is due to damaged Cardioversion (defibrillation) – very brief discharges of
valves that fail to prevent the backflow of blood. Blood then electricity are applied across the chest to stop a cardiac
collects in the veins, which distend to many times their normal arrhythmias & to allow a more normal rhythm to begin.
size. because of slow flow of bld. in varicose vein and Coronary bypass surgery (CABG) – vessel grafts,
frequent injury to the vein, thrombosis occur as well. consisting of veins taken from other parts of the body, are
Tx of varicose veins includes : wearing elastic stockings, anastomosed (connected) to existing coronary arteries to
elevation of the legs if edema occurs & Sx to ligate (tie off) detour around blockages in the coronary arteries & keep the
and strip (remove) the twisted, swollen veins called vein myocardium supplied w/ oxygenated blood.
stripping. Electrocardiography (ECG,EKG) – process of recording the
Hemorrhoids (piles) = are varicose veins near the anus. Sx Tx electricity flowing through the heart & thus the rhythm of the
includes: inj. of sclerosing solutions, ligation with rubber heartbeat.
bands & cryosurgery. Endarterectomy – surgical removal of the innermost lining
of an artery thickened by fatty deposits.
LABORATORY TESTS Extracorporeal circulation (ECC) – a heart-lung machine
Lipid tests – lipids are fatty subs. found in foods and in the (pump oxygenator) is used as a bypass to divert bld. from the
body. Measure the amounts of these subs. in a blood sample heart & lungs while the heart is being repaired.
Ex: cholesterol and triglycerides. Heart transplantation – a donor heart is transferred to a
 high levels of triglycerides & cholesterol in the recipient. The patient may need a left ventricular assist device
blood= greater risk of atherosclerosis. (LVAD)- booster pump implanted in the abdomen with a
 below 200 mg/dl in a middle-aged adult is cannula to the left ventricle.
associated= low risk for CAD. Holter monitoring – a compact version of an
 A diet high in saturated fat tends to increase the electrocardiograph is worn during a 24-hour period to detect
amount of cholesterol in the blood. cardiac arrhythmias.
 Polyunsaturated fats do not raise bld. cholesterol. Percutaneous Transluminal Coronary Angioplasty
Treatment: Hyperlipidemia is proper diet (low fat and & high (PTCA) catheter inserted via the femoral (thigh) artery &
fiber intake with fresh fruits and vegetables) and exercise. threaded up the aorta into a coronary artery.
Niacin (Vit. B6) is also helpful in reducing lipids. Balloon Valvuloplasty use is used to open narrowed cardiac
Drug therapy, HMG reductase inhibitors (HMGs) valves & is seen as a possible alternative to surgery for
ex. simvastatin, lovastatin, & pravastatin. HMG CoA valvular stenosis.
reductase(3-hydroxy-3-metyl-glutaryl-CoA reductase or Stress test – also known as exercise tolerance test (ETT), this
HMGR). procedure determines the heart’s response to physical exertion
Lipoprotein electrophoresis – proteins that carry lipids (fats) (stress).
in the bloodstream. Thrombolytic therapy – drugs such as tPA and strepto-
Protein electrophoresis is the process of physically kinase, w/c dissolve clots, are injected into the bloodstream.
separating lipoproteins from a bld.

CLINICAL PROCEDURES
X-Ray:
Angiography – dye is injected into bloodstream or heart
chamber, and x-ray films are taken of the heart & large bld.
vessels in the chest.
Arteriography- dye injected in aorta.
Digital subtraction angiography (DSA) – video equipment
& a computer are used to produce x-ray pictures of bld.
vessels.

Ultrasound Tests
Doppler ultrasound – an instrument is used to focus sound
waves on a bld. vessel
Echocardiography (ECHO)
Position emission tomography (PET) scan
Technetium 99m ventriculography (multiple-
gatedacquisition scan, or MUGA) – This radioactive test
studies the motion of the left ventricular wall and measures
the ventricle’s ability to eject bld. It is a test of the functioning
of heart & CO.