1. 先天性心脏病 Congenital Heart Disease (CHD)
（二）
Department of Pediatrics
Soochow University Affiliated Children’s Hospital

2. Patent Ductus Arteriosus (PDA) 动脉导管未闭

3. Learning objectives You should:
Know the signs , symptoms, diagnostic features and management of the common acyanotic congenital heart disease: PDA

4. PDA—concept 1 Which is ductus Arteriosus?
2. Ductus close in response to the rise in Po2 ,blood pH and prostacyclin after birth
3. If this mechanism fails or is reserved by prostaglandin E2, the resulting connection allows blood to flow under pressure from the aorta into the pulmonary arteries

5. PDA—concept 2
In a term infant ，ductus ateroisus closed spontaneously in 3 months in most infant cases.
Ductus arteroisus remained patent after one year old or more– named PDA

6. PDA—concept 3
1.In a term infant ，PDA is the result of a deficiency in the structural framework of the vessel wall.
2. In the preterm infant is the result of a delay in closure. Therefore, although 100% of premature babies born at 29weeks of gestation will have a PDA, in the vast majority this closes spontaneously.
3. In contrast, 6% of all term newborn have a persistent connection between the bifurcation of the pulmonary arteries and the aortic arch.

7. Patent Ductus Arteriosus (PDA)
L--R shunt CHD
10% of CHD
Twice as common in females as in males
In preterm infant weighing less than 1500Kg,the frequency of PDA :20%-60%
Associated lesions CoA ,or VSD(sometimes)

8. Types of PDA
funnel漏斗
tubiform管状
window窗型

9. Hemodynamics changes
The blood in lung field increased, Blood in systemic circulation decreased
Pulmonary hypertension(PH) ,reversible irreversible Eisenmenger syndrome
Cardiac enlargement (LV,LA)
Diameter of ascending aorta is large to normal
A widened Pulse Pressure LV AO PV LA
Pulmanory
circulation RV RA
Systemic
SVC
IVC PA
PDA

10. Symptoms (depending on the shunt of PDA)
None (most common)
recurrent chest infections
Heart failure with large shunt

11. Signs (depending on the shunt of PDA)
None (most common)
Pink, normal or large volume, bounding /collapsing pulse
BP shows wide Pulse Pressure
Precordium is hyperdynamic with LV impulse at apex
Thrill at left infraclavicular area and second left intercostal space possible
Loud P2 with pulmonary hypertension
Third heart sound (S3) with CCF
Pulmonary crepitations and hepatomegaly with CCF
Continuous waterwheel/machinery murmur loudest at upper LSE, left infraclavicular area and back

12. Practice ：typical murmur of PDA
e.g. Grade Ⅱ--Ⅳ /Ⅵ continuous, machinery murmur at the second LSE
Typical murmur of PDA:
1. Continuous waterwheel/ machinery murmur
2. Loudest murmur at upper LSE, left infraclavicular area and back CM

14. Investigation Chest X-ray (CXR) Electrocardiography(ECG)
Echocardiography(2DE)
Cardiac catheterization and angiocardiography

15. Chest X-ray Pulmonary plethora
The main pulmonary artery segment dilated
Cardiomegaly (LV,LA)
Diameter of ascending aorta is Large to normal 4 2 1 3
Normal
PDA case

16. ECG (typical PDA) Normal or left axis deviation
LA enlarged , LV hypertrophy

17. Echocardiography The anatomic location (the size and shunt of PDA)
Color flow doppler
(the direction of the shunt)
estimate the pressure
pulmonary pressure or hypertension

19. Cardiac catheterization and angiocardiography

20. Course and prognosis
Closure spontaneously in infant in the vast majority
Adults with corrected defect have normal quality of life

21. Management Medical management 1.fliud restriction
2.indomathacin and prostacyclin
Interventional therapy
1.Implantation of various umbrella or coil device
2.The first choice of treatment
Surgery ligation in premature infant

22. Amplatzer occluder device
Device for PDA closure
Amplatzer occluder device
Diameter of PDA>2.5mm.
Coiloccluder device
(弹簧圈）
Diameter of PDA<2.5mm.

25. Summary PDA is a kind of L to R shunt CHD,
The symptom of PDA depends on the shunt.
The characteristic heart murmur and P2
Complication: (1)Respiratory infection (2)congestive heart failure (3)endocarditis

26. Summary PDA can close spontaneously in infant
Enlarged chambers (LV,LA) can be observed by CXR , 2DE ,and ECG
Preventing PH is the key point during the management of PDA patients

27. Question
How to detect and estimate the PH in PDA patient in clinical experience? Why?
Important Concept:
Pulmonary hypertension
differential cyanosis (Eisenmenger syndrome)
A widened Pulse Pressure

28. Tetralogy of Fallot (TOF) 法洛四联症

29. Learning objectives You should;
Know the signs , symptoms, diagnostic features and management of the commonest cyanotic congenital heart disease-TOF

30. Questions for TOF How to treat it?
1.The mechanism and clinical findings of hypercyanotic episode (spells)?
How to treat it?
2. The mechanism of squatting suddenly in TOF patient?

31. Anatomy of TOF 2 1 3 4 Boot-shaped heart (RVOTO)
The aorta straddles both L and R ventricle 2
Boot-shaped heart
Beneath the aortic outlet 1 3
(RVOTO) 4
Resulting from RVOTO
Bay(隐凹) /Oligaemia (血量减少)

32. Hemodynamics changes The blood in lung field decreased (oligemia) LV
Cardiomegaly (RV,RA)
Diameter of ascending aorta is larger to normal. LV AO
systemic PV LA
SVC RA PA
pulmanory
VSD
Over-riding
RVOTO
RVH

33. Symptoms depending on the degree of RVOT obstruction
Cyanosis (variable, progressive)
hypercyanotic episode /blue spells /
Hypoxemic spells 缺氧发作
aged 2years or less
Squat suddenly after exertion
to ward off hypercyanotic spells
Exercise tolerance poor

34. Cyanosis (variable, progressive)
1.At birth the RVOT obstruction is usually not severe and cyanosis may not be obvious.
2.but this becomes evident with increasing activity, often when crawling commences around 10 months of age
3.Progressive hypoxemia results in compensatory polycythaemia, including clubbing fingers and toes (杵状指、趾）

35. Symptoms depending on the degree of RVOT obstruction
Cyanosis (variable, progressive)
hypercyanotic episode /blue spells /
Hypoxemic spells 缺氧发作
aged 2years or less
Need to lie down/ Squat suddenly after exertion
to ward off hypercyanotic spells
Exercise tolerance poor

36. Squat after exertion
Need to lie down/ Squat suddenly after exertion to ward off hypercyanotic spells

37. Symptoms depending on the degree of RVOT obstruction
Cyanosis (variable, progressive)
hypercyanotic episode /blue spells /
Hypoxemic spells 缺氧发作
aged 2years or less
Squat suddenly after exertion
to ward off hypercyanotic spells
Exercise tolerance poor Need to lie down/

38. Hypoxemic spells(缺氧发作)
Paroxysmal hypercyanotic episodes arise in untreated young children aged less than 2 years,
Following defecation 排便，crying or feeding .
Blue spells are characterised by
1.Increasing irritability
2.Prolonged crying
3. Rapid deep respiratory movement
4.A dramatic exacerbation of cyanosis
During blue spells, a significant increase in RVOT obstruction, blood flow through the outflow decrease ,and the systolic murmur disappears. (mechanism)

39. signs depending on the degree of RVOT obstruction
Central cyanosis
Plethoric appearance
Hyperdynamic precordium with RV heave at left sternal edge
Palpable systolic thrill at upper LSE in50% patients
S2 aortic and single ;(due to absent pulmonary component)
Heart murmur: GradeⅡ--Ⅳ /Ⅵ rough ESM at upper LSE radiating to back

40. Practice ：typical murmur of TOF
e.g. Grade Ⅱ--Ⅳ /Ⅵ ESM,
P2 weaken or disappeared
Loud ESM at the upper LSE due to turbulence caused by the infundibular stenosis
ESM
The large VSD little turblence and therefore does not produce a murmur.

41. Complications of TOF
Progressive cyanosis is associated with failure to thrive
Hypercyanotic spells may be associated with syncopal attacks
Cerebral ischaemia and thromboses usually occur in the first 2 years of life
Cerebral abscess develop in older children
Bacterial endocarditis and CCF are rare

42. Investigation Blood routine
Erythrocytosis , hyperglobulism and plasmahyperviscositysyndrome
Avoiding dehydration such as diarrhea, vomiting and sweating
Chest X-ray (CXR)
Electrocardiography(ECG)
Echocardiography(2DE)
Cardiac catheterization and angiocardiography
红细胞增多

43. Chest X-ray Normal TOF: Boot-shaped heart 4 2 3 1 Pulmonary oligaemia
Small pulmonary conus, (concave)
Cardiomegaly (RV,RA)
Diameter of ascending aorta is larger

44. ECG (typical TOF)
Right axis deviation
RV hypertrophy

45. Echocardiography The anatomic location Color flow doppler
the direction of the shunt
estimate the pressure gradient
of RVOT

46. Over-riding ventricle septum
VSD
VSD
Over-riding ventricle septum
Over-riding ventricle septum
VSD
RV outflow obstruction

47. Cardiac catheterization and angiocardiography

48. Medical management Attempts to improve weight gain are essential
An adequate haemoglobin should be maintained ,especially in patients with severe cyanosis and those with hypercyanotic spells
Emergent treatment for.hypercyanotic spells
1.placed knee to chest position (stimulated squatting)
2.Given oxygen
3.intravenous sodium bicarbonate (acidosis 酸中毒)
4.Intravenous morphine (sedation, relief pain and RVOTO)
5. Regular oral Propranolol (心得安) until surgery

49. Management---Surgery
The palliative blalock-Taussig shunt
improves pulmonary blood flow ,It is employed in severely cyanosed infants aged less than 6 months ,those who are medically unfit for a major procedure, and those with hypercyanotic spells
The definitive repair
involves total reconstruction of the RV outflow tract and closure of VSD, The operative mortality is less than 5%

50. Summary The commonest cyanotic CHD, R to L shunt The typical symptom :
1. Cyanosis after the neonatal period
2. Hypercyanotic spells during infancy
3. Squatting suddenly after infancy
The characteristic heart murmur and P2 decreased