先天性心脏病先天性心脏病 Congenital Heart Disease Congenital Heart Disease

(CHD)(CHD)（二）

Department of PediatricsSoochow University Affiliated Children’s Hospital

Patent Ductus Arteriosus(PDA)

动脉导管未闭

Learning objectives

You should:• Know the signs , symptoms, diagnostic fe

atures and management of the common acyanotic congenital heart disease: PDA

PDA—concept 1

2. Ductus2. 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

1. Which is ductus Arteriosus?

PDA—concept 2

1.1. In a term infant In a term infant ，， ductus aterductus ateroisus closed spontaneously in oisus closed spontaneously in 3 months3 months in most infant cases. in most infant cases.

2.2. Ductus arteroisusDuctus arteroisus remained premained patent after atent after one one year old or moryear old or more– named e– named PDA PDA

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.

Patent Ductus Arteriosus(PDA)

1. L--R shunt CHD

2. 10% of CHD

3. Twice as common in females as in males

4. In preterm infant weighing less than 1500Kg,the frequency of PDA :20%-60%

5. Associated lesions CoA ,or VSD(sometimes)

Types of PDA

funnel 漏斗

tubiform 管状

window 窗型

Hemodynamics changes

The blood in lung field increased, Blood in systemic circulation decreasedPulmonary hypertension(PH) ,reversible -------- irreversible Eisenmenger syndrome Cardiac enlargement (LV,LA)Diameter of ascending aorta is large to normalA widened Pulse Pressure

LV AOPV LA

Pulmanory

circulation

RV RA

Systemic

circulation

SVC

IVCPA

PDA

Symptoms (depending on the shunt of PDA)

None (most common)

recurrent chest infections

Heart failure with large shunt

Signs (depending on the shunt of PDA)

1. None (most common)

2. Pink, normal or large volume, bounding /collapsing pulse

3. BP shows wide Pulse Pressure

4. Precordium is hyperdynamic with LV impulse at apex

5. Thrill at left infraclavicular area and second left intercostal space possible

6. Loud P2 with pulmonary hypertension

7. Third heart sound (S3) with CCF

8. Pulmonary crepitations and hepatomegaly with CCF

9. Continuous waterwheel/machinery murmur loudest at upper LSE, left infraclavicular area and back

Investigation

Chest X-ray (CXR)Electrocardiography(ECG)Echocardiography(2DE)Cardiac catheterization and

angiocardiography

Chest X-ray1. Pulmonary plethora2. The main pulmonary artery segment dilated3. Cardiomegaly (LV,LA)4. Diameter of ascending aorta is Large to norma

l

Normal PDA case

3

1

2

4

ECG (typical PDA)

1. Normal or left axis deviation2. LA enlarged , LV hypertrophy

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

Cardiac catheterization and angiocardiography

Course and prognosis

Closure spontaneously in infant in the vast majority

Adults with corrected defect have normal quality of life

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

Amplatzer occluder deviceDiameter of PDA>2.5mm.

Coiloccluder device ( 弹簧圈）

Diameter of PDA<2.5mm.

Device for PDA closure

Summary

1. PDA is a kind of L to R shunt CHD,

2. The symptom of PDA depends on the shunt.

3. The characteristic heart murmur and P2

4. Complication: (1)Respiratory infection (2)congestive heart failure (3)endocarditis

Summary

5. PDA can close spontaneously in infant

6. Enlarged chambers (LV,LA) can be observed by CXR , 2DE ,and ECG

7. Preventing PH is the key point during the management of PDA patients

Question

1. How to detect and estimate the PH in PDA patient in clinical experience? Why?

2. Important Concept:

① Pulmonary hypertension② differential cyanosis (Eisenmenger syndrome)

③ A widened Pulse Pressure

Tetralogy of Fallot (TOF)

法洛四联症

Learning objectives

You should;• Know the signs , symptoms, diagnostic

features and management of the commonest cyanotic congenital heart disease-TOF

Questions for TOF

1.The mechanism and clinical findings of h

ypercyanotic episode (spells)?

How to treat it?

2. The mechanism of squatting suddenly i

n TOF patient?

Anatomy of TOF

Bay( 隐凹 ) /Oligaemia ( 血量减少 )

1

2

3

(RVOTO)

4

Beneath the aortic outlet

Resulting from RVOTO

The aorta straddles both L and R ventricle

Boot-shaped heart

Hemodynamics changes1. The blood in lung field decreased (oligemia)

2. Cardiomegaly (RV,RA)

3. Diameter of ascending aorta is larger to normal.

LV AO systemicPV LA

SVCRAPApulmanory

VSD Over-riding

RVOTO

RVH

Symptoms depending on the degree of RVOT obstruction

1. Cyanosis (variable, progressive)

2. hypercyanotic episode /blue spells /

Hypoxemic spells 缺氧发作 aged 2years or lessaged 2years or less

3. Squat suddenly after exertion

to ward off hypercyanotic spellsto ward off hypercyanotic spells

4. Exercise tolerance poor

1.At birth the RVOT obstruction is usually not severe and cyanosis may not be obvious.

3.Progressive hypoxemia results in compensatory polycythaemia, including clubbing fingers and toes ( 杵状指、趾）

2.but this becomes evident with increasing activity, often when crawling commences around 10 months of age

Cyanosis (variable, progressive)

Symptoms depending on the degree of RVOT obstruction

1. Cyanosis (variable, progressive)

2. hypercyanotic episode /blue spells /

Hypoxemic spells 缺氧发作 aged 2years or lessaged 2years or less

3. Need to lie down/ Squat suddenly after exertion

to ward off hypercyanotic spellsto ward off hypercyanotic spells

4. Exercise tolerance poor

Squat after exertion

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

Symptoms depending on the degree of RVOT obstruction

1. Cyanosis (variable, progressive)

2. hypercyanotic episode /blue spells /

Hypoxemic spells 缺氧发作 aged 2years or lessaged 2years or less

3. Squat suddenly after exertion

to ward off hypercyanotic spellsto ward off hypercyanotic spells Exercise tolerance poor Need to lie down/

Hypoxemic spells( 缺氧发作 )

Blue spells are characterised by 1.Increasing irritability 2.Prolonged crying

3. Rapid deep respiratory movement

4.A dramatic exacerbation of cyanosis

Paroxysmal hypercyanotic episodes arise in untreated young children aged less than 2 years,

Following defecation 排便， crying or feeding .

During blue spells, a significant increase in RVOT obstruction, blood flow through the outflow decrease ,and the systolic murmur disappears. (mechanism)

signs depending on the degree of RVOT obstruction

1. Central cyanosis 2. Plethoric appearance 3. Hyperdynamic precordium with RV heav

e at left sternal edge 4. Palpable systolic thrill at upper LSE in50

% patients5. S2 aortic and single ;(due to absent pul

monary component)6. Heart murmur: Grade -- / rough EⅡ Ⅳ Ⅵ

SM at upper LSE radiating to back

1. Loud ESM at the upper LSE due to turbulence caused by the infundibular stenosis

2. The large VSD little turblence and therefore does not produce a murmur.

e.g. Grade -- / ESM, Ⅱ Ⅳ ⅥP2 weaken or disappeared

ESM

Practice ： typical murmur of TOF

Complications of TOF

1. Progressive cyanosis is associated with failure to thrive

2. Hypercyanotic spells may be associated with syncopal attacks

3. Cerebral ischaemia and thromboses usually occur in the first 2 years of life

4. Cerebral abscess develop in older children

5. Bacterial endocarditis and CCF are rare

Investigation1. Blood routine

Erythrocytosis , hyperglobulism and plasmahErythrocytosis , hyperglobulism and plasmah

yperviscositysyndrome yperviscositysyndrome

Avoiding dehydration such as diarrhea, vomitiAvoiding dehydration such as diarrhea, vomiting and sweatingng and sweating

2. Chest X-ray (CXR)3. Electrocardiography(ECG)4. Echocardiography(2DE)5. Cardiac catheterization and angiocardi

ography 红细胞增多

Chest X-ray

1. Pulmonary oligaemia

2. Small pulmonary conus, (concave)

3. Cardiomegaly (RV,RA)

4. Diameter of ascending aorta is larger

TOF: Boot-shaped heartNormal

2

4

3

1

ECG (typical TOF)

1. Right axis deviation

2. RV hypertrophy

Echocardiography

1. The anatomic location

2. Color flow doppler

the direction of the shuntthe direction of the shunt

3. estimate the pressure gradient

of RVOT

VSD

VSD

VSD

Over-riding ventricle septum

Over-riding ventricle septum

RV outflow obstruction

Cardiac catheterization and angiocardiography

Medical management

Attempts to improve weight gain are essential

An adequate haemoglobin should be maintained ,especially i

n 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

Management---Surgery

1.1. The palliative blalock-Taussig shuntThe palliative blalock-Taussig shunt

improves pulmonary blood flow ,It is employed in sever

ely cyanosed infants aged less than 6 months ,those wh

o are medically unfit for a major procedure, and those wi

th hypercyanotic spells

2.2. The definitive repairThe definitive repair

involves total reconstruction of the RV outflow tract and

closure of VSD, The operative mortality is less than 5%

Summary

The commonest cyanotic CHD,The commonest cyanotic CHD,

R to L shuntR to L shunt

The typical symptom :The typical symptom :

1. 1. Cyanosis after the neonatal periodCyanosis after the neonatal period

2. Hypercyanotic spells during infancy2. Hypercyanotic spells during infancy

3. Squatting suddenly after infancy3. Squatting suddenly after infancy

The characteristic heart murmur and PThe characteristic heart murmur and P2 decreased 2 decreased