CV/PV Surgery

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Transcript CV/PV Surgery

CV/PV Surgery
Vessels

Arteries and veins
have 3 layers
– Tunica intima
 Innermost layer
– Tunica media
 Muscular middle
layer
– Tunica adventitia
 Fibrous outer
layer
Arteries

Arteries have a thicker muscular layer and
more elastic fibers than veins do, and
therefore are thicker walled then veins

Arteries carry O2 blood away from the
heart
– Exception: Pulmonary arteries carry
deoxygenated blood
Veins

Veins carry deoxygenated blood toward
the heart
– Exception: Pulmonary veins carry O2 blood
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Veins have thinner walls, and have
semilunar intimal folds (valves)
Vasa vasorum
– Tiny network of vessels in the walls of the
vessels which provides nourishment
Vessels
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Arteries
Arterioles
Capillaries
Venules
Veins
Know your major
arteries and veins!
Heart
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Enclosed in a pericardial sac
Walls of the heart are made up of 3 layers
– Epicardium
 Outer lining
– Myocardium
 Muscular, functional middle layer
– Endocardium
 Inner lining

Divided into right and left by a septum
Heart
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Four chambers
– Atrium
 Superior two
chambers
– Ventricle
 Inferior two
chambers
Atria
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Right
– Receives
deoxygenated
blood from the
inferior and
superior vena
cavae, and from
coronary
circulation via the
coronary sinus
Ventricles
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Right
– Pumps blood
through the
pulmonary valve
into the main
pulmonary artery,
which divides into
right and left
pulmonary
arteries to the
lungs
Atria
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Left
– Receives O2 blood
from the lungs via
the pulmonary
veins
Ventricles
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Left
– Pumps blood to
systemic
circulation via
the aorta,
through the
aortic valve
Coronary circulation
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Right and left
coronary arteries
Originate in the
sinuses of Valsalva
behind the cusps of
the aortic valve in
the ascending aorta
Heart Valves
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Tricuspid
Pulmonary
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Mitral
Aortic
Tricuspid
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Between the right atrium and right
ventricle
Consists of 3 leaflets
Pulmonary
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Between the right ventricle and the
pulmonary artery
Mitral
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Between the left atrium and left ventricle
Consists of 2 leaflets (AKA bicuspid)
Aortic
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Between the left ventricle and the aorta
Chordae tendineae
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Anchor the
bicuspid and
tricuspid valves to
the inner
ventricular wall
Prevents the valve
from everting into
the atria
Conduction
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Sinoatrial (SA) node
– Located in the area where the superior vena
cava meets the right atrium
– The process of excitation and contraction
originates here
– AKA- pacemaker of the heart
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Atrioventricular (AV) junction (node)
– In the right atrium, close to the tricuspid
valve
Conduction
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Bundle of His
– Extends down the right side of the septum
– Bundle divides into the right and left bundle
branches, which terminate in a network of
Purkinje fibers
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Purkinje fibers
– Spread throughout the inner surface of both
ventricles
– Stimulation produces contractions of the
ventricles
Blood Values
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Four Groups
–
–
–
–
Group
Group
Group
Group
A
B
AB
O
American Red Cross
Blood Type Facts
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Almost 40% of the population has O+
blood
Patients with Type O blood must receive
Type O blood
About half of all blood ordered by
hospitals in our area is Type O
Type O blood is the universal blood type and is
the only blood type that can be transfused to
patients with other blood types
 Only about 7% of all people have Type O
negative blood
 Type O negative blood is the preferred type for
accident victims and babies needing exchange
transfusions
 There is always a need for Type O donors
because their blood may be transfused to a
person of any blood type in an emergency
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If your blood type is…
Type
You Can Give Blood To
A+
O+
B+
AB+
AOBAB-
A+ AB+
O+ A+ B+ AB+
B+ AB+
AB+
A+ A- AB+ ABEveryone
B+ B- AB+ ABAB+ AB-
You Can Receive Blood From
A+ A- O+ OO+ OB+ B- O+ OEveryone
A- OOB- OAB- A- B- O-
RH Factor
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RH + blood given to an RH negative
person, recipient can produce
counteracting proteins (antibodies) which
will destroy the RH + blood cells
RH – mother may become sensitized by
the proteins from an RH + fetus, and
produce antibodies, possibly causing
erythroblastosis fetalis
Hematology Values
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Red blood cell (RBC) count
– Male - 4.3-5.9 million/ml
– Female - 3.5-5 million/ml
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Hematocrit
– % of blood volume made up of RBC’s
– Male - 40-52%
– Female - 35-46%
Hematology Values
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White blood cell
(WBC) count
– 5,000-10,000/ml
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Neutrophils
– 50-70%
Basophils
– 0.25-0.5%
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Differential
– % of WBC, by
type
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Eosinophils
– 1-3%
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Monocytes
– 2-6%
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Lymphocytes
– 25-40%
Vascular conditions
PVD & Arteriosclerosis
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PVD
– Peripheral Vascular Disease
– Non-specific term
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Arteriosclerosis
– A common arterial disorder characterized by
thickening, loss of elasticity, and calcification
of arterial walls
– Often develops with aging, and with
hypertension, nephrosclerosis, diabetes, and
hyperlipidemia
Atherosclerosis
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A common arterial disorder characterized
by yellowish plaques of cholesterol, lipids,
and cellular debris in the inner layers of
the walls of arteries
Often develops with
aging, and with
obesity,
hypertension, and
diabetes
Embolus
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A foreign object, a
quantity of air or gas,
a bit of tissue or tumor,
or a piece of thrombus
that circulates in the
bloodstream until it
becomes lodged in a
vessel
Thrombus
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aka- blood clot
An aggregation of platelets,
fibrin, clotting factors, and
the cellular elements of the
blood attached to the inner
wall of a vein or artery,
sometimes occluding the
vessel
Aneurysm
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A localized dilation
of the wall of a
blood vessel,
usually caused by
atherosclerosis and
hypertension
Aneurysm
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Several
different
types
TIA
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Transient Ischemic Attack
– Episode of neurologic dysfunction that
resolves within 24 hours
– May be caused by athromatous debris or a
thromboembolism from a carotid artery
Stroke
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Ischemia of brain
tissues by occlusion
by an embolus,
thrombus, or a
cerebral
hemorrhage
3rd leading cause
of death in the US
Claudication
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“to limp”
– Most common symptom of lower extremity
PVD
– Occurs with exercise distal to the obstruction
– AKA functional ischemia
– Blood flow is adequate at
rest but inadequate to
sustain exercise
CHF
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Congestive Heart Failure
– An abnormal condition that reflects poor
cardiac pumping
– Failure of the ventricle to eject blood
efficiently results in volume overload,
causing pulmonary and venous congestion
Valvular conditions
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Valvular Stenosis
– Valve leaflets are fibrous and stiff, with
uneven and adherent margins
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Valvular Insufficiency (incompetence)
– Valve leaflets with degeneration or
perforations, dilated annuli, or ruptured
chordae
– Produces regurgitation of blood into the
originating chamber
Considerations
Angiography

Injection of
contrast media
into the patients
arterial system
and tracking its
movements by xray
Doppler Scanning
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Probe directs an ultrasound beam that is
reflected back to the probe by moving
RBC’s, the velocity of which is then
converted into an audible signal through
a speaker
Temperature regulation
CAN be a problem
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Hypo/hyperthermia blankets
Warm or cold fluids
Blood should be warmed prior to
transfusion to prevent hypothermia
Fluids may be cooled to help lower body
temperature
Slush may be used to help lower body
temperature
Supply Considerations
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Umbilical tapes or
vessel loops used
for retraction and
vessel control
– Circumferential
control of the
vessel
Supply Considerations
Instrument Considerations
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Vascular clamps are non-crushing to
prevent undue trauma to vessels
– Patient must be heparinized prior to clamp
placement
– Distal clamp is placed first, then the proximal
clamp
– Proximal clamp is removed first, then the
distal
– Partial Occlusion Clamp
Suture Considerations
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Double-armed NA
vascular (prolene, GoreTex, Polyester) sutures
are used, and frequently
have a larger swaged
suture-to-needle ratio to
avoid leakage
– Moisten doctors hands for
tying prolene
Equipment
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Cardiac defibrillator
– External or Internal paddles
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Antiembolic stockings or sequential
compression devices should be worn
during and following the surgical
procedure
Blood may be salvaged for
autotransfusion (Cell saver)
Vascular grafts
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Polyester or velour (Dacron)
– May be woven or knitted
– Must be pre-clotted (blood or plasma), as
they are porous
– Some come already pre-clotted
(Hemashield), and so are not porous
Vascular grafts
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Polytetrafluoroethylene
(PTFE or Gore-Tex)
– Preclotting not required
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Straight or bifurcated
Patch grafts
Vein grafts
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In situ
– Vein is left in its place
– Side branches are ligated
– Valves are disrupted with
a valvulotome
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Reverse
– Vein is harvested
– Valves are not disrupted
Common CV/PV Drugs
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Heparin
– Anticoagulant
– Given systemically and used as an irrigant
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Protamine sulfate
– Heparin antagonist
– Reverses the anticoagulant effect of heparin
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Papaverine hydrochloride
– A vasodialator used to relax the smooth
muscle of the vessel
Surgical Interventions
Vascular
AAA
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Abdominal Aortic Aneurysm resection
Surgical obliteration of the aneurysm with
insertion of a synthetic prosthesis to
reestablish functional continuity
Usually occur below the level of the renal
arteries
AAA
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May involve the bifurcation and common
iliac arteries
– Distal graft may be placed at the iliacs
(aortoiliac bypass) or at the femorals
(aortofemoral)
– A bifurcated graft would be required
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Usually asymptomatic and found on
routine physical exam
More frequent in men than in women
AAA
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Symptoms of rupture include severe back
pain, hypotension, shock, and distal
vascular insufficiency
– True surgical emergency
 Carries a 50% mortality
– Prime surgical consideration when a rupture
occurs is control of hemorrhage by occlusion
of the aorta proximal to the point of rupture
AAA
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Supine position, prepped and draped so
that the groins are accessible (mid-chest
to mid-thigh)
Midline incision from xiphoid to pubis
If graft requires, withdraw blood for
preclot before systemic heparin is given
When the aortic clamp is released to
permit distal flow “declamping shock” or
severe hypotension may occur
Aortic Intraluminal Stent
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A new procedure for repair of abdominal
aortic aneurysms
Less invasive, less cost, and reduced
hospital stay
Procedure uses a balloon mounted
stent/graft
Placed using fluoroscopy across the
aneurysm site through a percutaneous
entry site in the femoral artery
Aortic Intraluminal Stent
Fem-Pop
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Femoral-Popliteal bypass
Bypass of an occluded
section of the femoral
artery, from the femoral
artery to the popliteal
artery
May be done with vein
graft or synthetic graft
Fem-Tib
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Femoral-Tibial bypass
Bypass of an occluded section of the
femoral artery, from the femoral artery to
the tibial artery
Vein graft is the preferred method
Fem-Fem
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Femorofemoral
bypass
Bypass of an
occluded iliac
artery
Synthetic graft
material is used
Arterial Embolectomy
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Incision is made
into the affected
artery to remove
thromboembolic
material and
restore blood flow
Amputation
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Performed to eliminate ischemic,
gangrenous, necrotic, or infected tissue
Often performed under regional
anesthesia
Patient should not witness the wrapping
or transport of the amputated limb
Flaps are tailored to provide fascial and
skin coverage to cushion the smoothed
ends of the bone
Amputation
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BKA
– Below knee
amputation
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AKA
– Above knee
amputation
Carotid Endarterectomy
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Removal of an atheroma
at the carotid artery
bifurcation
Performed to increase
cerebral perfusion and
decrease the risk of
embolization
May be done with or
without a shunt
Arteriovenous Fistula
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Direct connections between
an artery and a vein
Standard means of vascular
access for long term renal
dialysis
Radial artery and cephalic
vein
Fistula should heal for
about 3 weeks prior to use
Arteriovenous Shunt
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aka- Bridge Fistula
Conduit between an artery and a vein
A U-shaped graft is placed, usually using
PTFE
Varicose Vein Stripping
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The saphenous trunk (longest vein) may
be ligated and divided with subsequent
stripping and excision
Prior to entering the OR the patient
stands so the varicose veins can be
marked with an indelible marker
Varicose Vein Stripping
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Excision
– Multiple small varicosities are removed via
small incisions
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Stripping
– Indicated removal of a long segment,
frequently using a vein stripper
Surgical Interventions
Cardiovascular
Pacemaker
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Insertion of pacing electrodes and a pulse
generator
Endocardial leads are placed via a cutdown, just beneath the clavicle, into the
cephalic, subclavian, or external jugular
vein
– Under fluoroscopy the electrode is advanced
into the apex of the right ventricle
– Pulse generator is placed in a subcutaneous
pocket
– Usually performed under local anesthetic
Pacemaker Insertion
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Epicardial leads are
implanted in the
myocardium via a
transthoracic
approach
Avoid electromagnet
interference
(microwaves, ESU,
etc.)
ICD
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Automatic Implantable CardioverterDefibrillator
Recognizes potential life-threatening
episodes of ventricular tachycardia or
fibrillation via 2 sensing electrodes
Delivers a synchronized shock to
terminate it via 2 defibrillating electrodes
Myocardial or transvenous
Cardiopulmonary Bypass

aka: Extracorporeal Circulation or CPB
– Temporary substitution of a pump
oxygenator for the heart and lungs
– Allows the surgeon to stop the heart and
perform surgery in a relatively dry,
motionless field
– Allows the surgeon to manipulate the heart
(which can result in inefficient contraction
and reduction of cardiac output) without
jeopardizing perfusion to the rest of the body
Cardiopulmonary Bypass

Venous line
– Cannula in either in the right atrium, or in
the superior and inferior vena cavae- drains
the blood
– If the inside of the heart
must be accessed (valve
replacements, septal
defects) then bi-caval
cannulation must be
employed
Cardiopulmonary Bypass
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Bypass machine
– Oxygenated, filtered, and warmed or cooled
– Since the machine does the work of the
lungs the patient does not need to be
ventilated, so the lungs
are deflated
– Lines must be primed
to avoid air emboli
Cardiopulmonary Bypass
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Arterial line
– Cannula in the ascending aorta
 Returns blood to systemic circulation
– Aorta is cross-clamped to prevent blood from
flowing back into the heart
Cardiopulmonary Bypass
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Apical vent
– Cannula placed into the left ventricle to
remove air and fluid

Pump suction
– Used to return pooled blood from the
surgical site directly to the bypass machine
Cardiopulmonary Bypass
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Cardioplegia
– Infuse the coronary arteries with cold
solution containing potassium
– Reinfused about every 15-20 minutes
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Termination of CPB
–
–
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–
Patient warmed systemically
Cross clamps removed
Lungs inflated and ventilated
The patient is “weaned”
Cardiac Catheterization
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A catheter introduced through a femoral
cut down passed to the heart or
coronary arteries
Diagnosis
– Inject dye (chambers,
valves, arteries, etc)
– Measure intracardiac
pressure
– Evaluate heart function
PTCA
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Percutaneous Transluminal
Coronary Angioplasty
Balloon dilation of coronary
arteries for selected patients
with atherosclerotic
narrowing in a major
coronary artery
IABP

Intraortic Balloon Pump
– Left ventricular supportive device used to
assist a patient with prolonged myocardial
ischemia, reversible left ventricular failure, or
cardiogenic shock
– Reduces left ventricular workload and
increases delivery of O2 to the myocardium
– Balloon inserted into the descending thoracic
aorta just below the subclavian
Robotic Assisted
AESOP
 ZEUS
 da Vinci
 SOCRATES
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CABG
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Coronary Artery
Bypass Grafts
Single or multiple
bypasses are
performed, depending
on the number of
vessels affected and
the degree of
obstruction present
CABG
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Bypass may be performed using internal
mammary arteries and/or segments of
saphenous veins (other veins may be
used)
Performed via a median sternotomy with
or without cardiopulmonary bypass
CABG
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Bypass may be performed using internal
mammary arteries and/or segments of
saphenous veins (other veins may be
used)
Performed via a median sternotomy with
or without cardiopulmonary bypass
Valve Replacement
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Excision of a diseased
mitral (MVR) or aortic
(AVR) valve, and
replacement with a
prosthesis
Mechanical
– Tilt disc
– Ball-and-cage
– Leaflets
Valve Replacement

Biological
– Allografts (cadaveric)
 Cryopreserved
 Must be carefully
thawed prior to use
– Xenografts (porcine)
 Gluteraldehyde
storage solution
 Must be rinsed
thoroughly before
use
Valve Replacement

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Contamination of a valve can cause
serious postoperative endocarditis
Performed via a median sternotomy with
cardiopulmonary bypass
Aneurysms of the
Thoracic Aorta

Excision of an
aneurismal portion of
the aorta and
replacement with a
prosthetic graft

Bypass is required for
repair of aneurysms of
the ascending and arch
Surgical Interventions
Pediatric
Repair of an
Atrial Septal Defect (ASD)
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Congenital defect in the interatrial
septum may be tolerated early in life,
but the shunting of blood increases the
workload on the right side of the heart
Closed under direct vision by suturing
with or without a patch
Performed via a median sternotomy with
cardiopulmonary bypass
Repair of a
Ventricular Septal Defect (VSD)
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Small may be asymptomatic and well
tolerated, large requires closure, usually
with a patch
Closed under direct vision
Performed via a median sternotomy with
cardiopulmonary bypass
Tetrology of Fallot
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Most common congenital cardiac anomaly
in the cyanotic group
Cyanosis, as seen in the superficial
vessels of the skin, results from a
shunting of un-oxygenated blood into
systemic circulation
Tetrology of Fallot

Features
– Pulmonary
stenosis
– High VSD
– Overriding of the
septal defect by
the aorta
– Hypertrophy of
the Right
ventricle
Tetrology of Fallot
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Blood flow to the lungs decreases as a
result of the pulmonary obstruction, and a
right-to-left shunt of venous blood from
the right ventricle to the left ventricle and
aorta occurs
An open repair is done under direct vision
Performed via a median sternotomy with
cardiopulmonary bypass
Transposition of the
Great Arteries

The aorta arises from the right ventricle,
and the pulmonary artery arises from the
left ventricle, resulting in reversed
circulation
– To sustain life there must be a
communication between the 2 sides of the
heart, such as a patent foramen ovale
(between the atria)
Transposition of the
Great Arteries

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The newborn is cyanotic at birth, and
becomes severely incapacitated with an
enlarged heart that rapidly increases in
size and progresses to CHF
Repairs may be palliative (to increase
cardiac mixing) or corrective (Mustard,
Rastelli, or Senning)
Corrective procedures are performed via a
median sternotomy with cardiopulmonary
bypass
Situs Inversus


Displacement of the
viscera to the
opposite side of the
body
Organs and
structures are a
mirror image of their
normal placement
Closure of a Patent Ductus
Arteriosus PDA


Abnormal communication between the
aorta and the pulmonary artery, normal
during fetal development but which fails
to close soon after birth
Performed via a thoractomy approach, in
the lateral position, and does not require
cardiopulmonary bypass
Repair of Coarctation
of the Aorta

Excision of a constricted segment of the
aorta with subsequent end-to-end
anastomosis, with or without a graft

Performed via a thoractomy approach, in
the lateral position, and does not require
cardiopulmonary bypass
The End !
Have a Good Day 