Download Tetralogy of fallot - The department of cardiology, Calicut medical

TRICUSPID ATRESIA
Dr Bijilesh u
Senior Resident,
Dept. of Cardiology,
Medical College, Calicut
References
- Perloff ‘s text book of congenital heart diseases
- Moss and Adams ‘s text book of congenital cardiology
- Rudolph text book of pediatric cardiology
- Freedom’s natural and modified natural history of cong.heart diseases
- Andreson text book of congenital heart disease
- Figenbaum’ text book of echocardiography
- Hurst’s heart disease
- Braunwald’ heart diseases
- Langman’s Embryology
Defined as congenital absence or agenesis of
the tricuspid valve, with no direct
communication between the right atrium and
right ventricle
• Incidence : 0.06 per 1000 live births
• Prevalence : 1- 3% of CHD
(Report of New England Regional
Infant Cardiac Program – 1980)
HISTORY
• First reported by Kreysig in 1817
• Clinical features reported by Bellet and
Stewart in 1933
• Taussig and Brown in 1936
EMBRYOLOGY
• Early embryogenesis - process of expansion of
inlet portion of right ventricle coincides with
development of AV valves
• Embryological insult occurring later in
• Failure
of this
process
- atresia
of tricuspid
gestation
- Less
common
variety
- with well
valve
& absent
inletleaflets
portion of right ventricle
formed
but fused
• If valve fusion incomplete - tricuspid
stenosis
ANATOMY
Muscular
Membranous
Atrioventricular
• Most common type
– muscular (89%)
• Dimple or a localized fibrous thickening in the
floor of RA at expected site of tricuspid valve.
• Membranous type - membranous septum
forms floor of the RA at the expected location
of TV
• May be associated with
absent pulmonary valve
leaflets
• Atrioventricular canal type
Extremely rare (0.2%)
Leaflet of the common AV valve
seals off the only entrance into RV
MORPHOLOGICAL
CONSIDERATIONS
RA & ASD
• The right atrium is enlarged and hypertrophied.
• Interatrial communication is necessary for
survival
• Stretched patent foramen ovale - ¾ cases
• True ASD less common - ostium secundum type
• Rarely patent foramen ovale is obstructive and
may form an aneurysm of fossa ovalis
• Sometimes large enough to produce mitral
inflow obstruction
LA & LV
• Left atrium may be enlarged, especially when
pulmonary blood flow is increased
• Mitral valve is morphologically normal - rarely
incompetent
• LV is enlarged and hypertrophied
Right ventricle
Size of the RV varies – depends on size of VSD
Small and hypoplastic
Inflow
sinus
portion
With a or
large
VSD
or TGAabsent
- RV larger
Trabecular portion & outflow or conus region
often
Whenwell
VSDdeveloped
is small - only the conus is present
VSD in Tricuspid Atresia
Associated VSD - 90% of individuals during
infancy
Usually perimembranous
Can be muscular /malalignment types
Restrictive VSD’S cause
subpulmonic obstruction in pts with NRGA
subaortic obstruction in pts with TGA
At birth VSD is usually restrictive- permitting
adequate but not excessive PBF
40% of these defects close spontaneously/
decrease in size - acquired pulmonary atresia
Majority of defects close in the first yr of life
Classification -
Type 1
Type 2
Type 3
KUHNE
Normally related great arteries
D-transposition of great arteries
L- Transposition of great arteries
Type 1
Normally related great arteries (70 – 80%)
a. Intact IVS with pulmonary atresia( 9%)
b. Small VSD and pulmonary stenosis( 51%)
c. Large VSD without pulmonary stenosis ( 9%)
Type II
D-transposition of great arteries (12 – 25%)
a. VSD with pulmonary atresia( 2%)
b. VSD with pulmonary stenosis( 8%)
c. VSD without pulmonary stenosis(18%)
Type 3
L- Transposition or malposition of great arteries
(3-6%)
Associated with complex lesions
Truncus arteriosus
Endocardial cushion defect
Additional cardiovascular
abnormalities- 20%
• Coarctation of aorta – 8%
• Persistent left SVC
• Juxtaposition of atrial appendages
-50% of TA with TGA
• Right aortic arch
• Abnormalities of mitral apparatus- cleft in
AML,MVP ,direct attachment of leaflets to papillary
muscles
PHYSIOLOGY- TA
• Obligatory rt to left shunt at atrial level
• LA receives both the entire systemic and pulmonary
venous return
• Entire mixture flows into LV - sole pumping
chamber
TA WITH NRGA
PHYSIOLOGY
• Pulm artery blood flow is usually reduced
• Restrictive VSD - zone of subpulmonic stenosis.
• LV overload is curtailed but
at the cost of cyanosis
• 90% of cases
TA WITH NRGA
PHYSIOLOGY
• When VSD is non restrictive and pulmonary vascular
resistance is low
PBF and LV volume over load - excessive
Cyanosis is mild
TA with TGA
PHYSIOLOGY
• VSD is almost always non-restrictive and PS usually
absent
• Low PVR > abundant pulmonary arterial blood flow
• Minimal cyanosis,marked LV volume overload
• With restrictive vsd or infundibular narrowing
→diminished syst circulation
→metabolic acidosis and shock
SEX PREDILECTION
• TA with NRGA - Equal frequency in males & females
• TA with TGA
- male preponderance
- no male preponderance with
juxtaposition of atrial appendages
GENETICS
• Specific genetic causes - remain to be determined in
humans
• FOG2 gene may be involved
• Validated only in animal studies
• 22q11 deletion
• Familial recurrence is low
• Recurrence in siblings is only about 1%
NATURAL HISTORY
TA with NRGA with an intact IVS
• Few infants survive beyond 6 months without
surgical palliation
• Intense hypoxia and death ensue
unless ductus is patent
unless adequate systemic to PA collaterals
present
TA with NRGA & SMALL VSD
NATURAL HISTORY
• VSD closes spontaneously or become excessively
obstructive - majority die by one year
• Rarely a favorable balance achieved b/w VSD & PBF
permitting survival from 2nd to 5th decades
TA with NRGA & LARGE VSD.
NATURAL HISTORY
• Excessive PBF > vol. overload of LV and CCF
• Patients usually do not fare well
• Some have lived to ages 4 to 6 years
• Long survivals reported between ages 32 and 45 yrs
- in exceptional cases
TR. ATRESIA WITH TGA
NATURAL HISTORY
• Same poor longevity patterns hold for TA with TGA
and large VSD
• Exceptional survivals to mid-late teens reported
• TA with TGA with subaortic stenosis
( restrictive VSD) - ominous combination
Overall survival
in infants with TA
• 1 year- 72%.
• 5 years- 52%.
• 10 years- 46%
Franklin et al 1972 -1987, 237 patients
Survival of patients presenting in infancy with tricuspid
atresia to the Toronto Hospital for Sick Children, Tame et al , 101 patients, 1970 - 1984
Probability of surviving for 1 year was 64% and to 8 years was 55%
The overall surgical mortality for the palliative procedures was 35.8%
Physical examination- appearance
• Dysmorphic facies
- Cat-eye syndrome
- congenital coloboma
• JVP
- a wave amplitude increase due to restrictive
interatrial communication.
- Y descent is slow
Precordium
• LV impulse without an RV impulse in a cyanotic
patient
• Gentle RV impulse - TA with non restrictive VSD and
a well developed RV
• Palpable thrill if VSD is restrictive
AUSCULTATION
• First heart sound is single
• Second usually single - soft pulmonic component occasionally present
• TA with NRGA
- prominent murmur of restrictive VSD
– holosystolic maximal at mid to lower LSB
TA with TGA & increased PBF
AUSCULTATION
•
•
•
•
Holosystolic murmur – across VSD
S2 – single & loud
S3
MDM
Pulmonary vascular resistance – high
AUSCULTATION
• VSD murmur vanishes
AUSCULTATION
• TA with TGA
- coexisting pulmonic or subpulmonic stenosis
- midsystolic murmur – loudness and length vary
inversely with degree of obstruction
ECG
• Tall peaked right atrial P
waves - Himalayan P waves
• LV hypertrophy
• Absence of RV forces in
precordial leads
• QRS axis
- left and superior - type 1
- LAD or normal - type 2
CHEST X-RAY- TA WITH NRGA AND SMALL VSD
• Pulmonary vascularity reduced
• Pulmonary artery segment – inconspicuous
• Heart size – normal
• Right cardiac border
superior convexity
- enlarged RA
• Inferior part
flat or receding
- absence of RV
• LAO – Humped appearance of right
cardiac border
CXR - TA with TGA - no obstruction
• Lungs – plethoric
• LV, LA, RA – enlarged
• Right cardiac border
no hump-shaped
contour
– RV is relatively well
developed
CXR - TA with TGA and PS
•
•
•
•
Pulmonary blood flow is normal or reduced
Prominent RA
Convex LV
Narrow vascular pedicle
ECHOCARDIOGRAM
• Presence of an imperforate
linear echo density at the
location of normal TV
• Presence and size of the interatrial communication
• Presence and size of a VSD
• Relationship of the aorta and pulmonary artery
• Size of the RV and pulmonary arteries
• Presence and severity of infundibular or pulmonary
stenosis
• Presence and size of the ductus arteriosus
• Presence of aortic isthmus narrowing or coarctation
• Degree of mitral regurgitation
• Left ventricular function
CARDIAC CATHETERIZATION
• Limited role at present
Newborn
• Define sources of pulmonary blood flow
• Associated anomalies not clearly defined by echo
• TA with TGA - Obstruction at VSD or infundibulum
• Therapeutic role for balloon atrial septostomy
CARDIAC CATHETERIZATION
• Prior to Fontan
- Pulm.Vascular resistance
- Pulmonary artery size
- Pulmonary artery distortion - by previous surgery
• Older patients without definitive palliation
- detect collaterals from aorta - lungs
HEMODYNAMIC DATA
• Right atrial pressure is slightly higher than LAP
• Prominent ‘a ‘wave in the right atrium
-interatrial communication is restrictive
• LV systolic and EDP – normal
• LVEDP may increase with large VSD as PVR drops
and LV volume overload ensues
• Oxygen saturation (Sao2)
in systemic venous return
- lower than normal
- diminished Sao2 in
systemic arterial blood
• Sao2 of pulmonary venous
return - normal
• LA and LV saturations
- diminished
- obligatory R-L shunt
PGE1
INITIAL MEDICAL MANAGEMENT
• Maintain patency of the ductus before cardiac
catheterization or planned surgery
• Given as an infusion
• .025 – 0.1 mg/kg/mt
• Potential for apnea
• Fever , siezure, hypotension
• Balloon atrial septostomy may be done as part
of initial catheterization to improve the RA-LA
shunt
SURGICAL CARE
Palliative
Corrective therapy
PALLIATIVE SURGERY DECIDED IN
TERMS OF
Decreased pulmonary flow
Increased pulmonary flow
FOR ↓ PBF
• PBF - increased by surgical creation of an
aortopulmonary shunt
• Blalock & Taussig - Subclavian artery - ipsilateral PA
• Potts - Descending aorta – LPA
• Waterston-Cooley - Ascending aorta – RPA
• Modified Blalock-Taussig shunt
- Gore-Tex interposition graft
- Subclavian artery - PA
• Central aortopulmonary fenestration
- Gore-Tex shunt
• Glenn shunt
• Superior vena cava – RPA
• End-to- end
• Improves PBF and Sa o2
• No risk of pulmonary HTN
• Pulmonary AV
malformations later
↑ PBF
• Pulmonary artery banding
- In patients with
tricuspid atresia type II
CORRECTIVE SURGERY
• Fontan and Kreutzer
- physiologically corrective operation
- complete separation of the systemic and
pulmonary circuits
CHOUSSAT CRITERIA
• Age at operation – 4 and 15 yrs
- not strictly followed nowadays
• Normal sinus rhythm
• Normal systemic venous connections
• Normal right atrial size
• Normal pulmonary arterial mean pressure
- > = 15 mm Hg
• Low pulmonary vasc resistance
- 4 woods units/m2
• Adequate sized PA with diameter > 75% of aorta
• Normal LVEF (>60%)
• Absence of MR
• Absence of complicating factors from previous
surgeries
• THANK YOU.