right-to-left shunt.doc

8/14/2019 right-to-left shunt.doc

1/16

Chapter 10

RIGHT-TO-LEFT SHUNT

1. Tetralogy of Fallot2. Transposition of Great Arteries3. Tricuspid Atresia4. Others :

o Truncus arteriosuso Total Anoalous !ulonary

"enous Connection

General InfromationThis group is anifested #y cyanosis$ therefore$ ir is called Cyanotic

congenital heart diseases.

ection I :TETRALOGY OF FALLOT

(TOF)

Introduction% &t is the coonest cyanotic heart disease 'orld'ide.

Incidence

&t fors a#out 10%of all congenital heart disease

Pathology & Pathogenesis&t consists of 4 a(or coponents

i. Pulmonary s!nos"s) is usually in the infundi#ular region

""# R"$ &!nr"'ular y!rroy

"""# !nr"'ular S!al *!+!'

iv. O&!r-r","n$ aora) de*tropositioned i.e o+e to the right

Fro e#ryology$ heart de+elops fro a single heart tu#e 'hich is di+ided

#y a septu ,+entricular - arterial.

&n TOF$ the arterial septu di+ides une/ually in 'hich the left half is uch#igger than the right side$ and e+entually results into pulonary stenosis -o+er%riding aorta. This une/ual septation is also responsi#le for the foration of".


2/16

Haemodynamic ChangesThe " causes increased pressure on the right side leading 'hich

e+entually leads to cyanosis

Clinical Presentation

1. A$!) any are 1 year #efore presentation 'hen the child can 'al.oe ay e+en reach 5 ) 6years #efore presenting.

# .yanos"so the tie of presentation +aries and is deterined #y the se+erity

of the o#struction. The ore se+ere the o#struction$ the earlierthe presentation and +ice%+ersa.

o oe ay not e+en ha+e any cyanosis initially$ #ut as the patient

gro's older$ the cyanosis appears #ecause the stenosis #ecoesore se+ere.o The ore the cyanosis$ the ore the syptoatology$ therefore$

a patient at #irth presents earlier.o &t hardly seen in dar%sinned people

/# Easy +a"$ua"l"y

# E++or "nol!ran'!

2# S3ua"n$o On e*ertion$ the assues this position or nee%chest position

'hile sleeping. This position suggests TOF until pro+en other'ise.


3/16

S3ua"n$ os""on 4n!!-'!s os""on

o This posture is a physiological adaptation to hypo*ia. Theechaniss in+ol+ed are

a. Pressure effect of Shunting% 7hen the feoral andpopliteal +essels are folded$ there is increase in the resistanceand conse/uently the pressure in the systeic circulation$'hich also increase in the left +entricular pressure ,afterload$and finally reducing right%to%left shunting of #lood. ore #loodis then puped to the lungs for o*ygenation. This is the a(orreason.

#. Reduction of venous return% Copression of the feoral- popliteal +eins causes reduction in +enous return$ thus less#lood to right atriu and reduced pressure on the right side.

6. Fa"lur! o r"&!) The other coplains that the child is gro'ing as thechildren of the age.

5# Hy!r'yano"' 6 Hyo7"' 6 .yano"' lu! s!llso The echanis is that the infundi#ular region 'hich is uscular

goes into spas rapidly$ thus causing 'orsened cyanosis.o The precipitating factors are

i. 8otion 98*cessi+e cryingii. 8*cessi+e coldiii. ehydrationi+. &nfections+. ypoglycaeia+i. eta#olic acidosis

o The presentation ight #e lie ) the child starts to cryuncontrolla#ly$ then the lips #ecoe #lue$ he ay e+en ha+econ+ulsion$ fainting or syncopal attacs fro hypo*ia.

8.

.on&uls"on) fro hypercyanotic spells or #leeding into the #rain.

9. .ar,"o&as'ular a''",!n6sro8!) caused #y polycythaeia ,e.g !C" ;;


4/16

Physical Examination

Inspection1. Small +or $!sa"onal a$!) is seen often

2. .yanos"s) of +arying degree depeneding on the se+erity$ age of the

patient. &t ay #e a#sent in the young patient.

3. Poly'ya!m"a) is a physiological response to chronic hypo*ia. &t isrecogni=ed #y :

a. Con(uncti+al suffusion ) the con(uncti+a is reddened #eause the+essels #ecoe thic and tortous +essels.

#. >eddened #ucal ucosa

4. *"$"al 'lu"n$ ) depends on the degree of

5. : 9r!al!ssn!ss ) due to polycythaeia or soeties eta#olicacidosis ,copensatory hyper+entilation$ #ut is not due to heart failureor pulonary congestion.

Palpation6. L!+ aras!rnal a!&!) due to right +entricular hypertrophy

5# Sysol"' r"ll alon$ l!+ u!r s!rnal !,$!

Auscultation

8. S"n$l! an, so+ S - results fro pulonary stenosis

9. ;urmur ) it is either an e(ection systolic urur at the left uppersternal edge ,pulonary area or urur of " ) a pansystolicurur at the left lo'er sternal edge. ururs of " and pulonarystenosis are not heard at the sae tie$ one is usually heard to aethe diagnosis.

Investigation1. Full loo, 'oun) !olycythaeia

% Thro#ocytopaenia ) contri#utes to the #leedingdiathesis

2. 9loo, +"lm) &t is parado*ical it often sho's iron%deficiency ,not iron%deficiency anaeia. The reason is #ecause of any red cells andinade/uate iron. uch patient ust #e gi+en iron suppleent.

3. El!'roly!s < Ur!a) sho's eta#olic acidosis


5/16

4. 9loo, $as!s) The picture seen in cyanotic heart disease is #elo'o >educed !O2,hypo*iao >educed po &ncreased !CO2

The procedure in+ol+es taing arterial saple fro right radialartery after gi+en 100< of o*ygen for 10 inutes. &t is done here

routinely.

5. .!s =-ray% ho's the follo'ingo The heart si=e is often noralo >ight +entricular hypertrophyo !ulonary #ay ) due to the sall pulonary arteryo &n all$ the heart is #oot%shaped. This is only suggesti+e and

not diagnostic of TOF

o 8+idence of right sided aortic arch. &t is present in 25 ) 30< ofpatients. &t is also seen in other conditions

o There is reduced pulonary +ascular aring ,pulonaryoligaeia

6. El!'ro'ar,"o$ram (E.G)% ho'so >ight atrial elargeent ,>A8o >ight +entricular enlargeent ,>"8o >ight a*is de+iation ,>A

?ote ) >" and >A occur together often$ #ut not al'ays$ it

depends on the se+erity of the hypertrophy.


6/16

7. E'o'ar,"o$!ay % The 2%diensional ode sho'so >"o "o O+er%riding aortao !ulonary outflo' tract stenosis

8. .ar,"a' 'a!!r">a"on) >ight sided study sho'so &ncreased right +entricular pressureo >educed pulonary artery pressure )

#ecause of the o#stuructiono >educed saturation in aorta ,ne+er a#o+e

@5


7/16

""# Plasma !7'an$! 6 Eryroo"!s"s &s indicated 'hen the !C" B0< #ecause of the ris of

C"A or cere#ral a#scess. The procedure in+ol+es reo+ing the thic #lood in

ali/uots and replace it 'ith plasa preferra#ly , ornoral saline 'hich is good enough. !lasa - noral

saline are used #ecause they stay in the intra+ascularspace. o ?OT use glucose. The forula to calculate the +olue to #e is #elo'

Actual !C" ) esired !C"8*changed "olue DDDDDDDDDDDDDDDDDDDDDDDD E lood+olue

Actual !C"

lood "olue ;0l E ody 'eight

8.g Calculate the +olue re/uired to do plasa e*changefor a 10g%'eighed patient 'ith !C" of ;0< and #ring the!C" to 55


8/16

#. Treatent of ypercyanotic pells% &s an eeregency to a+oid #rain daage

Stepsi. !ut the patient in nee%chest position ) ost iportantii. Gi+e o*ygen #y face as or nasal cathter

iii. Gi+e intra+enous propanolol

ose :0.1g9g

&s different fro oral drug

Alternati+e is su#cutaneous or intrauscular orphia,has the dose.

&t rela*es the infundi#ulu% ide%effects of orphia are

i. addictionii. has narr' therapeutic range

% ?alophine is the antidote for orphine to*icity

i+. Gi+e odiu #icar#onate

! Surgical treatmentCan #e di+ided into

a. !alliati+e#. efiniti+e

!alliati+e urgery1. 9lalo'8-Tauss"$ Sun) &t is a close heart surgery that in+ol+es

shunting #lood fro systeic into pulonary circulation.

ose : 18/9g


9/16

"ypesi. .lass"'al ) u#cla+ian artey is cut and anastose 'ith

pulonary artery%% !ost%operati+ely$ no radial pulse is felt. , "his isone for chec#ing e$uality of pulse onexamination$collateral arteries open up to supply

the li#.

ii. ;o,"+"!,) u#cla+ian artery is not di+ided$ a $ra+ isinterposed #et'een the 2 +essels. The graft iscalled Gore%te* graft. Thus the radial artery is intactat the end of the surgey.%% &t is used for saller patients

%isadvantagei. !atient 'ill outgro' the graftii. Clot foration

Indices of Succesful Shunti. &ediately$ shunt urur 'hich is a continous lie in

!atent ductus areriosus$ is heard. ut in practice$ it is notoften heard$ though the operation is successful.

ii. Cyanosis should start disappearingiii. The syptoatolgy should #e uch #etter i.e patient#ecoes ore fit and reduced ris of hypercyanotic spells.

&'(ective Criteriai. !C" should strat falling and sta#ili=e at 45 to 55ight%toleft shunt$it is #ecause "C and &"C 'nd as aorta. ont e+en call it right%to%left shunt$ instead #lood flo'ing to the lungs is increased

Clinical Presentationi. &t ost often presents at #irth 'ithii. reathleness ) #ecause of the increased #lood flo' tot the lungs.

iii. Coughi+. ear failure+. Failure to thri+e

Physical Examiantioni. Cyanosisii. reathlessness9yspnoeaiii. Chest signs ) for pulonary oedea - infectionsi+. Features of heart failure ) as it is often associated 'ith it ,note$ it is

not often associated 'ith TOF particularly if the defect is large+. On auscultationo oud 2 'hich could #e either loud A2 or !2.

A2 ) #ecauses aorta is no' anterior to puaonaryartery

!2 ) ecause of increased #lood flo' in pulonaryartery$ though it lies #ehind the aorta.

o " urur ) if " is presento A urur D if A is present

Investigation

1. .!s =-ray: ho'so 8gg%on%side appearance of heart

o >ight +entricular enlargeent ,>A8o >ight atrial enlargeent ,>A8o &ncreased pulonary +scular aring ,!"o Cardioegaly

2. El!'ro'ar,"o$ram,8CG : ho's


12/16

o >ight +entricular hypertrophy ,>"o >ight atrial hypertrophy ) occur soetieso >ight A*is e+iation ,>A

/# E'o'ar,"o$rayo To define the structural anoaly using 2%diensional

ode

# .ar,"a' 'a!!r">a"ono &s diagnostic and therapeutico ut echocardiography is preferred dor diagnosis.o Therapeutic use is throught right%sided study passing a

#allon catheter inot the right atriu$ crossing foraeno+ale into the left atriu$ then inflate the #alloon$ andpull it #ac to ae the foraen o+ale patent and

creating atrial septal defect. This is called Ras8"n, ?s

Ar"al S!osomy

Management % edical - urgical

a! Medical1. Treatent of heart failure ) iuretics - igo*in

'! Surgical &s the ainstay of treatent

&ptions

1. 9lalo'8 @ Hanlon Ar"al S!!'omy) &s not an open heartsurgery. &t is done to create opening for i*ing of #lood.

2. ;usar, O!ra"on) &n+ol+es reo+ing atrial septu$ and di+et all#lood in right atriu into left atriu - left +entricle using Atrialaffle. The patient #ecoes pin draatically. The prognosis isgood$ #ut it is an open heart surgery.


13/16

3. Ar!r"al S"') &s open heart surgery lie ustard operation.

.on$!n"ally .orr!'!, Transos""on o+ Gr!a Ar!r"!s

There is atrio+entricular discordance

"entriculo%arterial discordance

There are usually associated lesionsliei. "ii. !ulonart stenosisiii. leeding disordersi+. "al+e incopetence

There should #e no syptos.

ection III :


14/16

TRI.USPI* ATRESIA

(TA)

Introduction &t is uch less coon than the first 2 conditions.

&t is also called Hni+entricular ,is the coonest e*aple ofuni+entricular heart disease

>ight +entricle is rudientary

The right connection is a#sent.

Clinical Presentation

&t +aries$ and depend on +entriculo%arterial connection.

a. &f there is "entriculo%arterial concordance i.e >" I!A$the features 'ould #e due to reduced pulonary #loodflo'$ therefore presents haeodynaically siilar toTOF.

#. &f it is "entriculo%arterial discordance i.e >"I Aorta -"I !A$ the patient presents 'ith cyanosis - heartfailure.

&n suary$ the presentation consists of 'yanos"sJ !ar +a"lur!

Investigation

1# .!s =-ray the features seen are +aria#le

Odd%looing shaped heart #ecause the right +entricle is a#sent

There ay #e increased ,as in TGA or reduced pulonary +asculararings


15/16

# E.G &s often suggesti+e ,not diagnostic. &t sho's

o >ight atrial hypertrophy ) is large if A is sall and+ice%+ersa

o uperior a*is de+iation

o eft +entricular hypertrophyThese features together in a cyanosed child is suggesti+e oftricuspid atresia

3. E'o'ar,"o$ray% is +ery diagnostic

4. .ar,"a' 'a!!r">a"on) sho's no entrance into right +entricle

2# An$"o$ray

Management

ost patients usually gi+e up in first year of life if no inter+ention istaen.

Treat heart failure

The definiti+e treatent is surgery :FonanBs o!ra"on) a classical operation for those 'ho ha+e

reduced #lood flo'. The procedure in+ol+es connecting right atriu topulonary artery."al+e conduit is used to allo' #lood to flo' in one direction i.e topulonary artery.


16/16

Differential Diagnosis of Tetralogy of Fallot

&n TOF$ patient is usually older e.g 6years 'hile in TGA - TA$ they dieearlier.

A B%onth old patient in heart failure - cyanoisThe differentials are : i. TGA

ii. Tricupid atresia A B%onth old 'ith no heart failure

The differentials arei. Tetralogy of Fallot ) thin of it firstii. Tricuspid atresia?ote ) TGA usually associates 'ith heart failure. There areother differentials e.giii. !ulonary atresia J "$ 'ith "$ consider it as

e*tree TOF$ #ut it presents uch earlieri+. Tricuspid atresia or Hni+entricular heart disease.

7hen you see heart failure 'ith cyanosis in older children$ thin of8isenenger syndroe.

right-to-left shunt.doc

Documents

Transcript of right-to-left shunt.doc