Congenital Heart Disease - · PDF fileDefine congenital heart disease Differentiate between cyanotic and Acyanotic CHD. ... Pathophysiology:

Congenital Heart Disease

Mohamed Waheed Elsharief.

MBBS, MSc. MD

Objectives

By the end of this lecture you should be

able to

Define congenital heart disease

Differentiate between cyanotic and

Acyanotic CHD.

Illustrate how to investigate a child when

suspecting CHD

Outline the management of common CHD

Definition and etiology

Any deviation in the sequence of

embryogenesis structural, functional or

positional defect presents at birth which

manifest any time after birth.

Normal embryogenesis depend genes,

enivroment infections (diabetes, drugs,)

Congenital Heart Disease (CHD)

Occurs in 8: 1000 of all live births

Simple way to classify is:

– L→R shunts (Acyanotic)

– Cyanotic CHD (R→L shunts)

– Obstructive lesions

Acyanotic Congenital Heart

Disease

Left-to-Right Shunt Lesions

Atrial Septal Defect (ASD)

Ventricular Septal Defect (VSD)

Atrioventricular Septal Defect (AV Canal)

Patent Ductus Arteriosus (PDA)

Atrial Septal Defect

ASD is an opening in the atrial septum

permitting free communication of blood

between the atria. Seen in 10% of all CHD.


There are 3 major types:

Secundum ASD – at the Fossa Ovalis, most common.

• Primum ASD – lower in position & is a form of ASVD, MV cleft.

• Sinus Venosus ASD – high in the atrial septum, associated w/partial anomalous venous return & the least common.


Clinical Signs & Symptoms

Rarely presents with signs of CHF or other cardiovascular symptoms.

• Most are asymptomatic but may have easy fatigability or mild growth failure.

• Cyanosis does not occur unless pulmonary HTN is present.



• Hyperactive precordium, RV heave, fixed widely

split S2.

• II-III/VI systolic ejection murmur @ LSB.

• Mid-diastolic murmur heard over LLSB.


Treatment:

Surgical or catherization laboratory closure is generally recommended for secundum ASD

• Closure is performed electively between ages 2 & 5 yrs to avoid late complications.

Surgical correction is done earlier in children w/ CHF or significant Pulm HTN.

Surgery is not indicated if there Pul HTN occur and shunt is reveresed

Ventricular Septal Defect

VSD – is an abnormal opening in the

ventricular septum, which allows free

communication between the Rt & Lt

ventricles. Accounts for 30% of CHD.


4 Types

Perimembranous (or membranous) – Most common.

Infundibular (subpulmonary or supracristal VSD) – involves the RV outflow tract.

• Muscular VSD – can be single or multiple.

• AVSD – inlet VSD, almost always involves AV valvular abnormalities.


Hemodynamics

The left to right shunt occurs secondary to PVR

being < SVR, not the higher pressure in the LV.

This leads to elevated RV & pulmonary pressures

& volume hypertrophy of the LA & LV.



• Small - moderate VSD, >5mm, are usually

asymptomatic and 50% will close spontaneously

by age 2yrs.

• Moderate – 10-5 large VSD, almost always have

symptoms and will require surgical repair.



• II-III/VI harsh holosystolic murmur heard along the LSB, more prominent with small VSD, maybe absent with a

very Large VSD.

• Prominent P2, Diastolic murmur.

• CHF, FTT, Respiratory infections, exercise intolerance

hyperactive precordium. Symptoms develop between 1 – 6

months


Treatment

• Small VSD - no surgical intervention, no

physical restrictions, just reassurance and

periodic follow-up and endocarditis prophylaxis.

• Symptomatic VSD - Medical treatment

initially with afterload reducers & diuretics.

Ventricular Septal Defect Treatment

Indications for Surgical Closure:

Large VSD w/ medically uncontrolled symptomatology & continued FTT.

Ages 6-12 mo w/ large VSD & Pulm. HTN

Age > 24 mo w/ Qp:Qs ratio > 2:1.

Supracristal VSD of any size, secondary to risk of

developing AV insufficiency.

Atrioventricular Septal Defect

AVSD results from incomplete fusion the the endocardial cushions, which help to form the lower portion of the atrial septum, the membranous portion of the ventricular septum and the septal leaflets of the triscupid and mitral valves.

They account for 4% OF ALL CHD.


Question:

What genetic disease is AVSD more

commonly seen in?

• Answer:

Down’s Syndrome (Trisomy 21), Seen in

20-25% of cases.


Complete AVSD



Incomplete AVSD maybe indistinguishable from

ASD - usually asymptomatic.

Congestive heart failure in infancy.

Recurrent pulmonary infections.

Failure to thrive.

Exercise intolerance, easy fatigability.

Late cyanosis from pulmonary vascular disease w/

R to L shunt.



Hyperactive precordium

Normal or accentuated 1st hrt sound

Wide, fixed splitting of S2

Pulmonary systolic ejection murmur w/thrill

Holosystolic murmur @ apex w/radiation to axilla

Mid-diastolic rumbling murmur @ LSB

Marked cardiac enlargement on CX-Ray

Atrioventricular Septal Defect Treatment

Surgery is always required.

Treat congestive symptoms.

Pulmonary banding maybe required in premature infants or infants < 5 kg.

Correction is done during infancy to avoid irreversible pulmonary vascular disease.

Mortality low w/incomplete 1-2% & as high as 5% with complete AVSD.

Patent Ductus Arteriosus

PDA – Persistence of the normal fetal vessel that joins the PA to the Aorta.

Normally closes in the 1st wk of life.

Accounts for 10% of all CHD, seen in 10% of

Female : Male ratio of 2:1

Often associated w/ coarctation & VSD.

PDA is associated with congenital Rubella syndrome


Hemodynamics

As a result of higher aortic pressure, blood shunts

L to R through the ductus from Aorta to PA.

Extent of the shunt depends on size of the ductus

& PVR:SVR.

Small PDA, pressures in PA, RV, RA are normal.


Hemodynamics

Large PDA, PA pressures are equal to systemic pressures. In extreme cases 70% of CO is shunted through the ductus to pulmonary circulation.

Leads to increased pulmonary vascular disease.



Small PDA’s are usually asymptomatic

Large PDA’s can result in symptoms of CHF, growth restriction, FTT.

Bounding arterial pulses

Widened pulse pressure

Enlarged heart, prominent apical impulse

Classic continuous machinary systolic murmur

Mid-diastolic murmur at the apex


Treatment

Indomethacin, inhibitor of prostaglandin synthesis can be used in premature infants.

PDA requires surgical or catheter closure.

Closure is required treatment heart failure & to prevent pulmonary vascular disease.

Usually done by ligation & division or intra vascular coil.

Mortality is < 1%

Obstructive Heart Lesions

Pulmonary Stenosis

Aortic Stenosis

Coarctation of the Aorta

Pulmonary Stenosis

Pulmonary Stenosis is obstruction in the region of either the pulmonary valve or the subpulmonary ventricular outflow tract.

Accounts for 7-10% of all CHD.

Most cases are isolated lesions

Maybe biscuspid or fusion of 2 or more leaflets.

Can present w/or w/o an intact ventricular septum.

Associated with Noonan’s syndrome

Pulmonary Stenosis

Hemodynamics

RV pressure hypertrophy RV failure.

RV pressures maybe > systemic pressure.

Post-stenotic dilation of main PA.

W/intact septum & severe stenosis R-L

shunt through PFO cyanosis.

Cyanosis is indicative of Critical PS.

Pulmonary Stenosis


Depends on the severity of obstruction.

Asymptomatic w/ mild PS < 30mmHg.

Mod-severe: 30-60mmHg, > 60mmHg

Prominent jugular a-wave, RV lift

Split 2nd hrt sound w/ a delay

Ejection click, followed by systolic murmur.

Heart failure & cyanosis seen in severe cases.

Pulmonary Stenosis

Treatment

Mild PS no intervention required, close follow-up.

Mod-severe – require relieve of stenosis.

Balloon valvuloplasty, treatment of choice.

Surgical valvotomy is also a consideration.

Aortic Stenosis

Aortic Stenosis is an obstruction to the outflow from the left ventricle at or near the aortic valve that causes a systolic pressure gradient of more than 10mmHg. Accounts for 7% of CHD.

3 Types

Valvular – Most common.

Subvalvular(subaortic) – involves the left outflow tract.

Supravalvular – involves the ascending aorta is the least common.

Aortic Stenosis

Question:

Which syndrome is supravalvular stenosis

found in?

Answer:

Williams Syndrome

Aortic Stenosis


Mild AS may present with exercise intolerance, easy fatigabiltity, but usually asymptomatic.

Moderate AS – Chest pain, dypsnea on exertion, dizziness & syncope.

Severe AS – Weak pulses, left sided heart failure, Sudden Death.

Aortic Stenosis


LV thrust at the Apex.

Systolic thrill @ rt base/suprasternal notch.

Ejection click, III-IV/VI systolic murmur @

RSB/LSB w/ radiation to the carotids.


Coarctation- is narrowing of the aorta at varying points anywhere from the transverse arch to the iliac bifurcation.

98% of coarctations are juxtaductal

Male: Female ratio 3:1.

Accounts for 7 % of all CHD.


Question:

What other heart anomaly is coarctation

associated with?

Answer:

Bicuspid aortic valve, seen in > 70% of

cases.


Question:

What genetic syndrome is coarctation seen

in?

Answer:

Turner’s Syndrome


Hemodynamics

Obstruction of left ventricular outflow

pressure hypertrophy of the LV.

Coarctation of the Aorta Clinical Signs & Symptoms

Classic signs of coarctation are diminution or absence of femoral pulses.

Higher BP in the upper extremities as compared to the lower extremities.

90% have systolic hypertension of the upper extremities.

Pulse discrepancy between rt & lt arms.



With severe coarc. LE hypoperfusion, acidosis, HF and shock.

Differential cyanosis if ductus is still open

II/VI systolic ejection murmur @ LSB.

Cardiomegaly, rib notching on X-ray.


Treatment

With severe coarctation maintaining the ductus with prostaglandin E is essential.

Surgical intervention, to prevent LV dysfunction.

Angioplasty is used by some centers.

Re-coarctation can occur, balloon angioplasty is the procedure of choice.

Cyanotic Heart Diseases

Eisenmenger’s

Syndrome

Tetralogy of Fallot

Anatomic Defects – Ventricular septal

defect

– Overriding Aorta

– Pulmonary artery

stenosis

– Right ventricular

hypertrophy

Picture: www.lpch.org

Tetralogy of Fallot

Pathophysiology: Increased resistance by the

pulmonary stenosis causes deoxygenated systemic venous return to be diverted from RV, through VSD to the overriding aorta and systemic circulation systemic hypoxemia and cyanosis

Picture: www.lpch.org

Tetralogy of Fallot

Symptoms:

– Dyspnea on exertion or when crying

– Tet spells: irritability, cyanosis, hyperventilation

and sometimes syncope or convulsions due to

cerebral hypoxemia.

– Patients learn to alleviate symptoms by squatting

which increases systemic resistance and decreases

the right-to-left shunt and directs more blood to the

pulmonary circulation.

Tetralogy of Fallot

Physical exam:

– Clubbing of the fingers and toes

– Systolic ejection murmur heard at the upper left sternal border created by turbulent blood flow through stenotic RV outflow tract

Lab Studies:

– High PCV

– CXR: prominent RV

– EKG: RVH, right axis deviation

– ECHO: displays and quantifies extent of RV outflow tract obstruction

What is the difference between these two films?-

both are infants with congenital heart disease.

Tetralogy of Fallot Treatment:

– Antibiotic with procedures

– Surgical closure of the VSD and enlargement of the pulmonary outflow tract

-Patient given beta blockers for prophylaxis against Tet spells

- Treat spells by

- Position knee chest

- Oxygen

- Fluids

- Morphine

- B blockers

- Complications Brain abscess thrombosis, iron deficiency

- Q can they present with heart failure?

Transposed

Great Arteries

Blue. Presents with

cyanosis when the duct

closes.

24 Hours to 2 Weeks

Cyanotic “Ductal-Dependent”

Lesions

CXR helps in diagnosis - oligaemic lungfields

PS, pulmonary atresia etc

- plethoric lungfields

TGA

- congestion

TAPVD

- massive cardiomegaly

Ebstein’s

What is the difference between these two films?-

both are infants with congenital heart disease.

Cyanotic infant- a lung

problem or a heart problem?

Investigations- suggests heart if:

- CXR- clear lung fields and

- ECG- normal and

- Hyperoxia test normal ( breathing 100%

oxygen, if pO2 >150mmHg very unlikely to be

cyanotic heart disease)

- (Echocardiogram is the definitive test)

24 Hours to 2 Weeks

Heart failure “Ductal-Dependent”

Lesions

Heart failure is due to left heart

obstruction NOT L-R shunts at this

age! eg.

– Coarctation

– Critical Aortic stenosis

– Hypoplastic left heart

– Mitral stenosis (rare)

Documents

Congenital Heart Disease - · PDF fileDefine congenital heart disease Differentiate between cyanotic and Acyanotic CHD. ... Pathophysiology: