1. Assessment for operability of
CHD with PAH
R. Tandon

2. CONGENITAL HEART DISEASE
8 to 10 / 1000 live births
Uncorrected – 30 % PAH
PPH of new born
Idiop. Ped. PAH

3. L > R Shunt with PAH Acyanotic CHD - PDA - VSD - AVSD - AP Window
- ASD
Cyanotic CHD with ↑ Qp
(Transposition physiology)

4. Cyanotic CHD with ↑ Qp (Transposition physiology)
Complete TGA
DORV, ↑ Qp
TA, ↑ Qp
PTA
SV, ↑ Qp
TAPVC
Miscellaneous malp. without
obstr. to pulm. blood flow

5. Congenital Heart Disease
Pulm. Circ: PAH
CHD -↑ QP, ↑ Pr, ↑ O2 sat, ??
Hypoperf, 2° to under development
Blood Viscosity
Thrombo–embolic obstr.
Aorto–pulm. Collat.

6. Congenital Heart Disease
Pulm. hypertension :
PA Pr. = Pulm flow x PVR
Hyperkinetic =  flow
Obstructive =  PVR

7. Principles Low resistance pulmonary circuit 1) Qp 2) Vol. overload
High resistance pulmonary circuit
1) Curtailment of Qp
2) Loss of volume loading

8. CONGENITAL HEART DISEASE
PAH :
Hyperkinetic - PVR normal
Obstructive - PVR ↑
Due to PVH - PVR normal, ± ↑

9. CONGENITAL HEART DISEASE
Pulmonary Hypertension : dx
PA (m) ↑ 25
PAW/LAm/LVedp 15 mm or ↓
PVR ↑ 3u
(Incorrect)

10. Factors determining development of PVOD
Type of intracardiac defect
Age
 PA Pressure
 PV Pressure
 PBF, PAO2
Hypoxia
Acidosis
Unexplained - ? Genetic suscept.
? Endoth. dysf.

11. Congenital Heart Disease
Pulmonary hypertension : Operability
Age
Lesion
Physical findings
Systemic O2 saturation
Investigations
Non-invasive
Invasive

12. Congenital Heart Disease
PVOD : Age
Unknown  3 m
Rare  6 m
Uncommon  1 yr
Except in TGA physiology

13. Congenital Heart Disease
 in PVR :
Improving symptoms
 in CCF
Improved exercise capacity
Cyanosis : Absent, intermittent, persistent.

14. Congenital Heart Disease
PVOD : Lesion
Very early -  3 m
TGA Physio., AP window, Comp. AVC defects
Large PDA earlier than VSD (↓ 1 yr).
ASD – rare

15. Pulmonary hypertension
Hyperkinetic Obstructive
Heart size large normal (except in ASD)
Parasternal hyperkinetic forcible or heaving in ASD
impulse mild in VSD & PDA
Click of PAH absent present
Second sound ASD‑wide & fixed ASD - wide and fixed
(P2 accent‑ VSD‑wide & variable VSD - single
uated in both) PDA‑paradoxically PDA - normal
split
Shunt murmur loud short or absent
Flow murmur present absent

16. Congenital Heart Disease
PVOD : Syst. O2 saturation
L  R shunt -  93% - PVR 
 95%,  PVR not excluded
TGA physiol. -  85% high flow and low PVR

17. Congenital Heart Disease
PVOD
ECG : Increasing RVH - Not helpful
X-ray : * Heart size 
* Pulm. Vasculature
Characteristics changes appear too late.

18. Congenital Heart Disease
Pulm. hypertension :
Echo assessment :
PA syst. pr - Good
PA diast. pr - Reasonable
PA mean pr - Poor
For assessment of PVR – cath is gold standard and essential.

19. Congenital Heart Disease Invasive evaluation
Hemodynamic study.
Pulmonary wedge angiography.
Biopsy – Pulmonary histology.
Pulmonary vascular compliance.
(MRI & intravascular ultrasound)

20. CONGENITAL HEART DISEASE
PAH Cath study:
Pressures – RA,RV,PA, PAW, LA/LVED,SA
Saturations – SVc, RA,RV,PA,SA
VO2, CI, SVR, PVR HR
pO2, pH
Effect of intervention.

21. Cardiac Catheterisation
Measurement of PAP
Measurement of PVR
Vascular Reactivity
PVR = PAm - LAm Qp
If PVR & PAH  - pO2 and pH essential.

23. Congenital Heart Disease
Flow: (Poiseuille)
ΔP. π r4 Q=
8ŋL

24. Congenital Heart Disease
PAH:
PA (m) – LA (m) . 8Lη
PVR=
Qp π r4
Assumes constant steady flow

25. Congenital Heart Disease
Assessment for reactivity :
Oxygen
Isuprel infusion
Nifedipine
Prostaglandin
SNP, NO.
PVR ↓ 6 units – operable.

26. Congenital Heart Disease
Flows:
VO2
Qp=
PVO2 – PAO2
Qs=
PVO2 (SA) – MVO2
Qp= Qs

27. Congenital Heart Disease
Pulmonary hypertension : VO2
Must be measured
Assumed value cannot be used
For PVR calculation to determine operability.

28. Congenital Heart Disease
Flows: Qp/Qs ratio
SAO2 – MVO2
Qp/Qs=
PVO2 – PAO2
Eliminates need to measure VO2

29. Congenital Heart Disease
Flows: Qp/Qs ratio
SAO2 – MVO2
PV (SA)O2 – PAO2
Echo: SVLV
SV X HR = Qs
Qp from Qp/Qs

30. CONGENITAL HEART DISEASE
PAH – PVR
Fixed : PVOD
Variable: Vasoconstr - 20% pts.

31. Congenital Heart Disease
PAH:
Operable – PVR ↓ 6u Rest or ac.
Inoperable – PVR ↑ 8u testing.
Grey zone 7u ±1.

32. CONGENITAL HEART DISEASE
PAH Vasodilat testing :
Identifies - Prognosis
- Responders
(utility of CCB)

33. PULMONARY HYPERTENSION AC. VASODILAT TESTING All PATIENTS
Contraindications : RV failure
Unstable haemodynamics
+ Ve resp. : PA (m)→ ↓ by 10 mms
absolute level ↓ 40 mms (no ↓ in Co.)
20% ↓ in PApr & PVR

34. Congenital Heart Disease
Pulm. hypertension : Reversibility
Qp on the basis of assumed VO2 - not reliable
100% : O2–VO2 not known, hence all calculation will be incorrect.
Dissolved O2 -  (modifies calculations)

35. Congenital Heart Disease
PVOD : O2 study
PA saturation increases abnormally giving increased calculated QP and low PVR.
Fall in PA pressure more reliable. Fall in PA diast. pr may result in lower mean pressure.

36. Problems with vasodilators
Oxygen fick’s principle NA
- Failure to respond in patients with reactive airway disease
Tolazoline,PG, Ca Block
- Fall in SVR
- Arterial hypotension
- VP mismatch
Isoprenaline - Very high heart rates

37. CONGENITAL HEART DISEASE
PAH : Nitric oxide:
Vasodilator
Inhibits - Platelet activation
- SMC proliferation
↓ levels in PAH
NO → cGMP
(inactivated by PDE-5, large amounts in lungs)

38. NO Advantages - No ↑ in syst. sat. - No systemic hypotension
- No arterial hypoxemia
Disadvantages
- Methaemoglobinemia
- Pulmonary edema
- Lung injury

39. NO as Pulmonary vasodilator - Results
NO at 40 ppm more effective than 5 ppm
3/15 (20 %) pt with PVR > 8 u
fall in PVR < 6 after NO
Response same in those with Down Syndrome
Yasuda T et al,Paediatric Cardiol,2000

40. NO vs NO + Oxygen combination
Number of responders with combination significantly > than when NO/Oxygen used alone.
Combination of NO + 02 provides add’nal pulmonary vasodilatation & can rapidly identify patients with pulmonary vasoreactivity.
Good postoperative results
Lock et al , JACC 2000

41. NO + Oxygen combination : PVR 10 u
O2 alone PVR 8 u
O2 + NO PVR 6 u
Does not guarantee operability
Wilkinson heart 2001 : 85:113

42. (Heath. Edwards classification)
Lung biopsy
Open lung specimen is taken
General anaesthesia
Biopsy those with borderline haemodynamics
(Heath. Edwards classification)

43. CONGENITAL HEART DISEASE
PAH
Creating ASD - RVF not relieved
R → L shunt - ↓ RA pr.
QP ↓, Syst. O2 sat. ↓
CO more stable – syncope relieved.
Change in life span - ?

44. Congenital Heart Disease
PVOD : Defect occlusion
PDA & some VSDs
Significant fall in PA pressure is helpful in decision making.

46. CONGENITAL HEART DISEASE
PAH Treatment
Prostanoids - Epoprostenol IV
E.R.A. - Bosentan PO
PDE-5-I - Sildenafil PO
CCB - Diltiazem, Amlodip. PO

47. CONGENITAL HEART DISEASE
PAH: Breathe – 5 : ASD & VSD
Bosentan Vs Placebo – 54 pts., class III, 16 weeks
Syst. O2 Sat. maintained.
PVR, PAm ↓
Ex. Cap.↑, funct. class ↑
Time to deterioration ↓
Placebo – PVR worsened (?)

48. CONGENITAL HEART DISEASE
PAH : Bosentan : Long FU (12 m – 29 m)
PVR/ SVR ratio ↓ (N to ↓ 0.3)
Qp & Qs ↑, R →L shunt ↓
PAp & SAp ↓ (NS)
RV after load ↓ more than LV
Initial improvement returns to baseline in 2 years.

49. CONGENITAL HEART DISEASE
PAH : Bosentan
Hepatotoxicity
Potentially teratogenic
Testicular atrophy & infertility
Hormonal birth control - ↓ effectiveness.

50. CONGENITAL HEART DISEASE
PAH : Sildenafil
PAp (m) ↓ 3-5 mms
Ex. capacity ↑
Side effects – minor
Functional class ↑

51. CONGENITAL HEART DISEASE
PAH : Eisenmenger ASD
40 pts., FU – 4 years, PVR ↑ 7u
ASD closed 26, Med. Rx -14
PVR No ↑ in PVR
PVR ↓
No vasoreactivity check pre op
PVR ↑ in all unopted.
Steele etal Circ : 76 :

52. CONGENITAL HEART DISEASE
PAH : Eisenmenger Pts : O2 ± No
124 Pts, 1 mt 47 yr. (m 28)
74 op or transplant
PVR/ SVR – 0.33 or ↑
O2 → Rp/Rs ↓ 0.42
O2 + NO Rp/Rs ↓ 0.27
(indicates operable defect)
Balzer etal Circ : 106:

53. Operability & Reversibility
Not Synonymous
Patients with severe intimal proliferation may not show decrease in PAP post-op
PAH can progress after repair

54. Congenital Heart Disease
PVR : mistakes in assessment
Presence of A.V. valve regurg.
Obligatory shunts
Pulm. infection, acidosis, anemia, polycythemia, hypoxia

55. SUMMARY Knowledge of determinants of progression of PVOD is poor
Remember confounding factors affecting PVR in assessing L→R shunts.
Clinical auscultation- fading art.

56. SUMMARY Age of patient probably THE most important determinant
* Pre tricuspid shunt except TAPVC- Longer waiting period
* Post tricuspid shunt without cyanosis
6 months to 1 year
* Post tricuspid shunt with cyanosis
before 3 months

57. Message Timely surgical intervention is THE KEY
for good immediate & long term
results.

58. Thank you