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