Transcript Lecture 22.Clinical pathophysiology of th cardiovascular system

Clinical pathophysiology
of the cardiovascular
system.
Blood Pressure
Exhibits a normal distribution within the
population
 Increasing blood pressure is associated
with a progressive increase in the risk of
stroke and cardiovascular disease
 Risk however rises exponentially and not
linearly with pressure

At what blood pressure is a patient
hypertensive?
BHS
140/90
 JNC-VI
140/90 Opt <120/<80
 WHO-ISH
140/90
 The current recommendation in the UK is
140/90
 However risk is important and in diabetes
130/80
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In 95% of cases no cause can be found

In 5-10% a cause can be found
– Chronic renal disease
– Renal artery stenosis
– Endocrine disease, Cushings, Conn’s
Syndrome, Phaeochromocytoma, GRA
 Home
Blood Pressure
Monitoring
– Mercury sphygmomanometer
 Standard for BP monitoring
 No calibration
 May be bulky
 Need a second person to use machine
 May be difficult for hearing impaired or
patients with arthritis
 Home
Blood Pressure
Monitoring
– Aneroid equipment
 Inexpensive, lightweight and portable
 Two person operation/need stethoscope
 Delicate mechanism, easily damaged
 Needs calibration with mercury
sphygmomanometer
 Home
Blood Pressure
Monitoring
– Automatic equipment
 Contained in one unit
 Portable with easy-to-read digital display
 Expensive, fragile
 Must be calibrated
 Requires careful cuff placement
Electrocardiogram

It is the method of registration of heart
bioelectrical potential from the chest of
patient
Electro gram of cardiac muscle
Waves of ECG
1. P wave – depolarization of atria,
precedes atria systole
 2. QRS wave is depolarization of
ventricles, precedes ventricular systole
 3. atria repolarization also occurs at QRS
 4. T wave indicates ventricular
repolarization

ECG leads
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a) Bipolar limb leads. The bipolar limb leads
record the voltage between electrodes placed on
the wrists and legs. These leads were proposed
by Einthoven in 1913.
I lead: left arm (+) - right arm (-);
II lead: left leg (+) - right arm (-);
III lead: left arm (+) - left leg (-).
For recording limb leads we put red electrode on
right arm, yellow - on left arm, green - on left
leg and black - on right leg. Black electrode has
zero potential (ground).
ECG leads

The unipolar limb leads were proposed by
Goldberger in 1942. They record voltage
between single “exploratory electrode” fro
one limb and zero joined electrode from
two other limbs. So there are three leads
AVR, AVL, AVF. In fact zero electrodes
records middle voltage of two limbs.
Bipolar limb leads and unipolar limb leads
record electrical power in frontal
projection.
ECG leads
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V1 - in crossing right IV right intercostal space
and parasternal line;
V2 - in crossing left IV intercostal space and
parasternal line;
V3 - between V2 and V4;
V4 - in crossing V left intercostal space and
medioclavicular line;
V5 - in crossing V left intercostal space and
anterior axilar line;
V6 - in crossing V left intercostal space and
middle axilar line.
Holter Monitor
Echocardiography
1.
 2.
 3.
 4.

M-measure
D-measure
Doppler
Contrasting
II position
АО
Cardiac Biomarkers
1. MI is diagnosed when blood levels of sensitive and
specific biomarkers, such as cardiac troponin (I or T)
and CK-MB (mass assay) are increased to values
greater than 99% of a normal reference population
(with less than 10% coefficient of variation of the
assay)
2. These biomarkers reflect myocardial damage, but do
not indicate its mechanism
3. ASAT, LDH isoenzymes should not be used to
diagnose myocardial damage
c1183higgin05[1]video2.mpeg
Roentgenogram
NORMAL
MITRAL STENOSIS
ROENTGENOGRAM
NORMAL
AORTIC STENOSIS
Thank
you!