the cardiovascular system william harvey (1628) demonstrated that the circulatory system forms a...
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The Cardiovascular System
William Harvey (1628) demonstrated that the circulatory system forms a circle so that blood is continuously pumped out of the heart by way of another set of vessels. (i.e. Arteries and Veins)
The Cardiovascular SystemHeart attacks are, perhaps, the number one killer in the USA. In middle
age and older persons, the probability of developing a coronary disease increases with:
1. Smoking
2. Obesity
3. Cholesterol/triglycerides
4. Abnormal ECG
5. Hypertension
The Cardiovascular System
I. Blood Vascular
A. Heart
B. Arteries
C. Capillaries
D. Veins
II. Lymphatic Vascular
A. Lymphatic Capillaries
B. Lymphatic Vessels
Thoracic Duct
Right Lymphatic Duct
Impulse ConductionA-V Node
Junctional fibers (0.01m/s)
Node (0.1m/s)
Transitional (0.4m/sec)
Bundle of His
Branches of bundle of His E Purkinje fibersrate L5 to 4.0 m/sec
AtrionodalNodal
Nodal His
Cardiac Action Potentials
Atrial Myocradial cell
Ventricular Myocradial cell
Pace-maker
1. Resting potential2. Spike (rapid depolarization)3. Plateau (Ca++ perinmeability )4. Repolarization
-90
-90-6040
1
23
4No+
in Coin
K+
set
P
Q S
RT
Electrocardiogram (ECG)
I. Unipolar (V) leads (9 locations)
A. Chest leads (precordial)
V 1- 6 B. Limb leads
VR (right arm) VL (left arm) VF (left foot)
II. Bipolar Limb Leads I. from RA to LA
II. from RA to LL III. from LA to LL
The ECG is the algebraic sum of the electrical events which occur during a heart beat. These signals are transmitted via the body fluids to the body surface where they are recorded by electric amplifiers. The series of pikes and depressions have arbitrarily been labeled
Relationship between Monophasic Action Potential
and Ventricular Activity
Depolarization Repolarization
R
Q
T
S
ECG
Duration Event Ave. Range
PR interval 0.18 0.12-0.20 Atrial Dep. Through AV
QRS duration 0.08 0.006-0.10 Aent. Dep.
QT interval 0.40 0.37-0.43 Vent. Dep + Repol.
ST interval 0.32 Vent. Repolarization
PR segment
QRS Duration
QT interval
ST segment
PR interval
P
Q S
T
R
Pathological Conditions Mean Electrical Axis
(mark changes in current flow)Left Axis Deviation
(hypertrophy of left ventricle) 1. Hypertension
(muscle mass on left side of heart) 2. Aortic Valvular stenosis 3. Aortic Valvular regurgitation 4. Several congenital heart conditionsRight Axis Deviation 1. Hypertrophy of right ventricle
(pulmonary stenosis) 2. Tetralogy of Fallot
(congenital right to left shunt )
I. Correlation of Plasma K+ Level
a. Noraml (plasma K+ 4 - 5.5 mEq/l)
b. Hypokalemia (plasma K+ + 2.5 mEq/l)
c. Hypokalemia (plasma K+ + 2.3 mEq/l)
d. Hyperkalemia (K+ + 7.0)
e. Hyperkalemia (K+ + 8.5
II. Atrial Enlargement
a. “p” pulmonale
b. “p” mitrale
Cardiac Arrhythmias
p tu
tu
Origin of the heartbeat & the electrical activity of the heart
Cardiac Rhythms & Arrhytmias
Cardiovascular Pressures & Sounds
Key (color)Key (color)1. Left ventricular 1. Left ventricular P.P.2. Aortic pressure2. Aortic pressure3. Left atrial p.3. Left atrial p.
Electrocardiogram
Phonocardiogram1. Lub2. Dub3. Rapid ventricular filling4. Atrial contraction
Dicrotic notch
14 2 3
closes opensmitral valve
a c v
aortic valveopens closes
120 -100 -
80 -60 -40 -20 -
0 -
Art
eria
le
cap
ille
ries
Ven
ale
Comparison of Pressures Within the Circulatory System
120
100
80
60
40
20
0
Aor
ta
Lar
ge a
rter
ies
Mai
n a
rter
ial b
ran
ch
Ter
min
al a
rter
ies
Ter
min
al v
ein
s
Mai
n v
enou
s b
ran
ch
Lar
ge v
ein
s
Ven
a ca
va
Systolic Pressure
Diastolic Pressure
Heart Sounds
120-
100-
80-
60-
40-
20-
0
120-
80-
40-
0 0.2 0.4 0.6 0.8
Ventricle
Systole Disstole1
2
34
5
6
Volume (ml)
Pressure (mmHg)
Heart sounds2nd 3rd1st
Time seconds
Heart Murmurs(Bruits - Outside the heart)
Types:
A Innocent (functional)
B pathogenics (non-functional)1. Stenosis - narrowing of valve
2. Regurgitant (insufficient)
3. Prolaspse
C. Congential
2. Patent ductus arteriosis
2. Interventricular septal defect
Heart Murmurs(Bruits - Outside the heart)
Valve Name Abnormality Timing of Murmur
Stenosis Systolic
Regurgitation Diastolic
Stenosis Diastolic
Regurgitation Systolic
Aortic or
Pulmonary
Mitral or
Tricuspid
Rheumatic Vascular lesions cause an autoimmune disease inwhich the heart valves are likely to be damaged .It is caused by a group A streptococcal toxin such as the oneswhich cause sore throat, scarlet fever, or middle ear infection.
Heart & Circulation1.Blood
Blood cells become packed at the bottom of the tube when whole blood is centrifuged, leaving the fluid at the top of the tube. Red blood cells are the most abundant of the blood cells -- white cells & platelets float ?? Only a thin, light-colored “buffy coat” at the interface between the packed red blood cells and the plasma.
Blood volume 80-85 ml/kg body weightBlood osmoiality 280-296 mOsmBlood pH 7.35-7.45Enzymes:Creatine Female: 10-79 U/L phosphokinase (CPK) Male : 17-148 U/L Lactic Dehydrogenase 45-90 U/L(LDH)Phosphate (acid) Female: 0.01-0.56
Sigma U/ml Male: 0.13-0.63 Sigma
Measurement Normal RangeRepresentative normal plasma values
Hematology Values:Hematocrit Female: 37%-48% Male: 45%-52%Hemoglobin Female: 12-15 g/100ml Male: 13-18 g/100mlRed blood cell count 4.2-5.9 million/mm3White blood cell count 4,300-10,880/mm3
Hormones Testosterone Male: 300-1,100ng/100mlAdrenocorticotropic (ACTH) 15-70 pg/mlGrowth hormone Children: over 10ag/ml Adult male: below 5 mg/mlInsulin 6-26 * U/ml (fasting)
Measurement Normal RangeRepresentative normal plasma values
IonsBicarbonate 24-30mmol/lCalcium 2.1-2. 6mmol/lChloride 100-106mmol/lPotassium 3.5-5.0mmol/lSodium 135-145mmol/1
Measurement Normal RangeRepresentative normal plasma values
Measurement Normal RangeRepresentative normal plasma values
Organic Molecules (other)Cholesterol 120-220mg/100mlGlucose 70-110mg/100ml (fasting)Lactic acid 0.6-1.6mmol/lProtein (total) 6.0-8.4g/100mlTriglyceride 40-150mg/100mlUrea nitrogen 8-25mg/100mlUric acid 3-7 mg/100ml
Hemostasis
Mechanisms
1. Vascular Spasms (vasoconstricitions)
2. Formation of Platelet Plug
3. Blood Coagulation
Table 13.4 Plasma Clotting Factors
* Require Vitamin K
+ Antihemophilic factors
*
*
* +
+* +
Table 13.5 Some acquired and inherited defects in the clotting mechanism
Extrinsic pathway
Common pathway
Intrinsic pathway
Extrinsic pathway
Activator:tissue thromboplastin
VII VII activated
VII complex(VII, tissue
thromboplastin,calcium,
phospholipids)Common pathway
Common pathway
Intrinsic pathwayActivators:
collagen,gas, and others
XII XII activated
XI XI activated
IX IX activated
VIII complex(VIII, (X activated,
calcium, phospholipids)
Common pathway
Fibrinogen FibrinFibrin
polymerXIII
V complex (V, X activated, calcium, phospolipids
Prothrombin Thrombin
X X activated
Extrinsic pathway
Intrinsic pathway
Prevention of Blood ClottingA. In-Vivo
1. Endothelial Surface Factors (Prostocyclin)
2. Heparin: A conjugated polysaccharide produced by mast cells (basophils)
3. Coumarin(Warfarin) & Phenindione: orally administered; blocks the synthesis of Vit.-K dependent clotting factors
4. Aspirin
Prevention of Blood ClottingB. In-Vitro
1. Removal of Ca++
a. Oxalates
b. Citrates
c. Chelating agents (EDTA)
2. Inhibition of vitamin-K
Dicumarol (coumarin) 3. Aspirin
Inhibits platelet aggregation
EDTA A chelate of
ethylenediamine tetraacetate with a divalent metal cation (Me2+). The shaded portion represents the plane of the coordination bonds
Me 2+
O
O
O
O
O
O
OO
C
C
C
C
CH2
CH2
CH2
CH2
CH2
CH2
N
N
Causes for Excessive Bleeding
1. Vitamin-K Deficiency
Factors II, VII, IX & X
2. Hemophilia
Factors VII (75%), IX (15%), & XI (5-10%)
3. Thrombocyopenia
Intrinsic Pathway Extrinsic Pathway
ContactActivation
ActivatedPlatelets
ActivatedPlatelets
Vessel DamageVessel Damage
Exposed CollagenSubendothelial CellsExposed to Blood
Tissue FactorXII
XI
IX IX
X
V
X
Prothrobin
VIII
VII
VIIaXIIa
XIa
Ixa
XIIIa
Xa
Va
Thrombin