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Timing and indications for surgery in congenital heart diseaseDr B R JAGANNATHStar HospitalsHyderabad
•Give a man a fish he will not go hungry for the day teach a man to fish he will not go hungry for the rest of his life
◦The Holy Bible
Provided he stays near a compatible water body
General principles
•(a+b)^2= a^2 +b^2 +2ab•TOE •E= mc^2•And so on •Can there be a mathematical or logical
approach ?
•The principle used in maths /physics•Factor in all variables•Group them if possible•Find a best fit equation that describes the
process
objectives
•Identify variables in predicting the timing of surgery
•Define groups of patients•Create a model for predicting the timing
and indications for surgery•Run a few case studies for the model
At the end
•You should be able to figure out the management pathway for most congenital heart surgery
•hopefully
•In CHD possible groups are •Patient related factors•Doctor and team related •Environment factors
Patient related
•Age •Weight•presentation•Clinical diagnosis•Anticipated procedure•Possible special situations in routine
procedure
Age related
•Three areas mainly or transitions▫Neonates transits from fetal to newborn▫Toddler transits from protected social
environment to school going▫Adolescent transits to adult
Importance of Ageneonates•Neonate is transition from fetal conditions
to outside world conditions•Hypoxic hypercarbic environment to low
CO2 and higher O2 concentration•Birth process may result in aspiration
/immunological insults/ unrecognized CNS damage/ acidosis/
•Stresses are unimaginable
Changes that follow
•Fetal Hb changes to adult Hb•Result hyperbilirubinaemia •Hepatic overload •Coagulation defects not directly
measurable
•Maturation of organs mainly the▫pulmonary▫CNS
Assesment of cns maturity is difficult Unrecognised defects may be attributed to
surgery Effect of surgery on CNS is little better
known▫Cardiac ▫Renal ▫ gut
Pulmonary changes
•Fetal PVRI is high •PBF is low •After birth PBF increases•Duct closes •PVRI starts to drop and should complete
in three months
•No real time data •No demonstrated mechanism for the
regression of PVR▫Relaxation of PC Sphincters▫Recanalization of capillaries▫Flow in tertiary vessels or just volume
expansion•No pathological process for non regression of
fetal PVRI•Most cardiac lesions are associated with
variations in PVRI
•What is the effect of cardiac lesions on the PVR regression
•All these effects are compounded if the child is premature
•Coagulation defects and hemorrhage at time of surgery
•Low circulating volumes wild fluctuations /massive transfusions and related TRALI
•Immature organs – easy damage and prolonged recovery times
•Cardiac protection is unpredictable
Net effect of age on timingneonates•Although we say that today the age does not
play a role in surgery• It is with these unpredictable that the risk is
quoted •The effect of surgery, anesthesia, CPB on end
organs• In long term we are still in the dark•At the end of the day we still worry whether
we have prevented some Einstein/Yacoub/Tausig from coming into the world
Nevertheless certain situations are unavoidable in neonates•ASO •Norwood and related single ventricle
situations•BT shunts for PA •TAPVC obstructed or unobstructed• question is even in neonatal period
when?
In neonatal period
•If possible avoid 1st week•Avoid rushing into OT from delivery room•Always step back think take a deep
breath•Proceed simultaneously along diagnostics
and management pathways
Age toddler • Protected environment gives way to wider
social circle • Infection in community are easily imported into
OT/ICU But
• Lesions are defined • Anatomy becomes a major decisive factor• But advantage is pvri? Settled • Organs better suited • Myocardial protection is better studied and
predictable
Net effect of toddler age
•More predictable •Less of emergency•Better substrate subject to anatomy
being favorable
Age adolescents
•Main changes are hormonal related to sexual maturation
•In post op social behavioral changes •Technology has provided us with more
effective valves/pacemakers etc•Decision making especially anatomy /PVR
are easier•Relatively larger structures easy surgery
Axiom age
•If the lesion allows growth & development unhindered preferable to operate later
•Second best bet would be closed heart surgery which may be curative
•Option would be palliative closed heart surgery
•Corrective surgery after stabilization
Weight
•As related to age and prematurity•Basically technical issues dominate•Need for smaller lighter less traumatic
instruments •Canulation options need planning
As related to perfusion support
•Miniaturization of circuits•Advanced microplegia systems•Smaller canulae•Use of vacuum assisted venous drainage•Use of advanced oxygenators
Net effect of weight
•Todays world this would be negated by experience of the team and advances in technology
Presentation
•All of us know •Emergency vs Urgent vs elective surgery•Cyanotic vs acyanotic •Open heart or cpb supported vs closed
heart•Palliative vs ? Curative vs really curative
New concept
•State of pulmonary blood flow ▫Increased pulmonary blood flow▫Reduced pulmonary blood flow ▫Balanced pulmonary blood flow
▫Pulmonary vascular resistanceNon regressedRegressed and increasingFixed
Permutations and combinations
Pulmonary blood flowa) Increased pulmonary blood flowb) Reduced pulmonary blood flow c) Balanced pulmonary blood flow
PVRIx) Non regressedy) Regressed and increasingz) Fixed
Possible combinationsPulmonary blood flowVascular resistance
Increased
A
Reduced
B
Normal
C
UnregressedX
Not likely Too late for any interventionTrial of medical mgmt
Needs medical managementPlan elective surgery
Regressed but increasingY
Needs surgeryAY
Needs rigorous investigation and urgent surgery if indicated
Investigate think before surgery or intervention
Fixed highZ
unlikely Too late Palliative optionsMedical options
Closer look at AY
•The rate of increase of PVRI is not predictable
•Although criteria exists but when it becomes inoperable is unpredictable
Anatomy at presentation
•Two ventricle repair is best option•Single ventricle option is prudent choice•Deciding between complex two ventricle
and single ventricle ?
Doctor and team related
•Type of surgery palliative or curative•Experience anecdotal or series•Skills both surgical and non surgical•Risk vs benefits and gut feeling
Type of surgery
•Palliative may not always be technically easier
•Palliative may be associated with longer stay more morbidity
•Palliation may complicate the issues for the corrective surgery
Environmental factors
•Need for special equipment•Need for prosthetic material •Need for conduits homografts etc•Logistics of above •Costs of above
Social factors
•Terms of financial support•Results of suboptimal outcomes •Socioeconomic support systems•Need for recurrent surgery
/medication/investigation
At the end of the day
•Should we•What•When•Still remain the crux of the problem
See a few examples
•Tetrology of Fallot•Atrioventricular septal defect
•DORV•Single ventricle staged
•Single ventricle single stage•TAPVC