Congenital Congenital Heart DiseasesHeart Diseases

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Questions we face

1. Does the child have a heart disease?

2. Is it congenital heart disease?

3. What type of lesion?4. What is the severity of

the lesion?

CHD

• DEFINITION– PRESENT AT BIRTH

• INCIDENCE– 6-8 PER 1000 LIVE BIRTHS IN WESTERN COUNTRIES

• ETIOLOGY– IN MAJORITY NOT KNOWN– EQUAL IN BOTH SEXES

APPROACH TO CHD

• DOES THE PATIENT REALLY HAVE CHD

• IS THE PATIENT CYANOTIC OR ACYANOTIC

• IS PULM ARTERIAL BLOO FLOW INC OR NOT

• LEFT OR RIGHT SIDE• DOMINANT VENTRICLE• PULM HTN PRESENT OR NOT

• HISTORY– PRENATAL - DM,DRUG ABUSE,SLE

– INFANT - FEEDING DIFFICULTIES

• SYMPTOMS OF CHF– POOR WEIGHT GAIN,DIFFICULTY IN FEEDING– BREATHS TOO FAST & BREATHS BETTER– WHEN HELD AGAIST THE SHOULDER– PERSISTENT COUGH & WHEEZING– IRRITABILITY,– EXCESSIVE PERSPIRATION & RESTLESSNESS– PUFFINESS OF FACE & PEDAL EDEMA.

Approach to CHD• Does the child have Heart Disease? NADAS Criteria

MAJOR1. Systolic murmur Gr. III or

> intensity2. Diastolic murmur3. Cyanosis4. CHF

MINOR1. Systolic murmur Gr. II

intensity2. Abnormal 2nd Sound 3. Abnormal ECG4. Abnormal Chest X Ray5. Abnormal Blood Pressure

•Presence of 1 major or 2 minor criteria suggest Presence of 1 major or 2 minor criteria suggest presence of Heart Diseasepresence of Heart Disease

Approach to CHD• IS the Heart Disease Congenital?

CONGENITAL1. Recognition early in age2. Murmurs more

parasternally 3. Presence of central

cyanosis4. Presence of extra-cardiac

anomalies

ACQUIRED1. H/o. joint pains,

fever

2. Apical murmurs

Approach to Heart disease

Cyanotic CHDAcyanotic CHD

PatientApply NADAS’ Criteria

Heart Disease Present Heart Disease Absent

Re-evaluate after Six months

L R Shunts

Obstructive Lesions

Regurgitant lesions

CHDs

Shunting

Stenotic R - > L L - > R MixingAortic Stenosis

Tetrology of Fallot

Patent ducturs

Truncus

Pulmonic Stenosis

Transposition VSD TAPVR

Coarctation Tricuspid atresia

ASD HLH

Approach to CHD

• Is it Acyanotic or Cyanotic

CYANOTIC

1. Clinical cyanosis – Uniform or Differential

2. R/o. respiratory, CNS or metabolic causes

3. Presence of polycythemia

4. Fast regression of Thymus on X-Ray

Approach to CHD• Pulmonary Blood Flow

Is it Normal / Increased / Decreased

INCREASED1. Rec. respiratory infections 2. Cyanosis Mild in Cyanotic CHDs3. Chest X- Ray

• Main pulmonary artery segment increased in size

• Rt. And Lt. PA branches larger• Plethoric lung fields

Second Heart Sound S2

S2

A2 P2

Accentuated

Diminished

Delayed

Early

SH, AR

Calc.AV, Aortic Atresia

AS, PDA, AR, LVF, LBBB

VSD, MR

PAH

PS, PA

PS, ASD, TAPVC, RBBB

Spliting of Second Heart Sound

Expiration InspirationSpliting

Normal

Wide & Variable

Paradoxical

Wide & Fixed

Single Second Sound

MR, VSD, PS

ASD, TAPVC, RBBB

AS, PDA, AR

TOF

Chief complaints

• Breathlessness• Palpitation • Chest pain• Cough• Edema • Failure to thrive • Joint pain / swelling • Syncope

History

• Gestational and natal history– Infections, (Rubella in 1st trimester, Mumps, CMV,

HSV, Coxsackie virus B)

– Maternal Conditions• Diabetes, advanced age, SLE, alcoholism, cigarette smoking, etc.

– Medications• Amphetamines, Phynetoin, trimethadone, Progesterone – estrogen

– Birth weight• IUGR, LGA

History• Postnatal history

– Weight gain• Feeding pattern

– Prolonged feeding time with multiple interruptions– Dyspnoea during feeding– Poor feeding

• Exercise Tolerance– Fatigue while climbing, running, bicycle riding

• Cyanosis– Onset, nature, spells

• Chest Pain– Deep, heavy pressure, feeling of chocking, triggered by

exercise, not effected by respiration• Palpitation

– PAT, MVP• Syncope

– Differentiate from epilepsy, breath holding spells, hysterical events

• Frequency of respiratory infections– Rec. LRIs, Rec. wheezing or strider

• Joint symptoms– Sore throat and joint symptoms

• Neurological symptoms– Stroke – cyanotic CHDs, headache – hypoxia,

polycythemia, cerebral abscess– Choreic movements– Syncope – ventricular arrhythmias, long QT, MVP

• Medications– Antihistamines, aminophylline

• Prior records• Family History

– Hypertension, CHDs, Rh. fever

History

Physical Examination

• General examination• Growth• Respiration• Excessive sweating• Colour

– Cyanosis– Pallor– Jaundice

• Clubbing• Edema• Extracardiac anomalies

Pulse

• Peripheral pusles– Lower limb pulses reduced in coarctation of aorta

• Acyanosis with bradycardia – AV canal defects

• Acyanosis with tachycardia– VSD

• Acyanosis with wide pulse pressure– PDA, VSD with AR, AP window

JVP

• Prominent ‘a’ wave : – Pulmonay stenosis

• Absent ‘a’ wave:– Pulm. Hypertension due to L->R shunt

• V waves – Tricuspid regurgitation

Signs & Symptoms of Infective Endocarditis

• H/o CHD or any procedures

• Fever • Chills • Chest & abdominal pain• Dyspnea• Night sweats• Weight loss• CNS Manifestations• Elevated temperature • Tachycardia

• Embolic Phenomena – Roth spot, osler nodes, petechiae, splinter nail bed hemorrages

• Janeway lesions• New or changing

murmurs• Splenomegaly• Arthritis • Heart failure• Clubbing • Metastatic infection

Signs & Symptoms of PHT

• History of Congenital Heart disease

• Breathlessness, fatigue, syncope on exertion

• Chest pain• Hemoptysis

Signs & Symptoms of failure

• Feeding difficulty• Hepatomegaly • Edema on dependent parts• Failure to thrive• Feeding difficulty• Forehead sweating• Breathlessness

CHDs

• Specific lesions

Ventricular Septal Defects

Type of VSD

Anatomic location is important with regard to chance of spontaneous closure, surgical approach, risk of conducting

system involvement and associated valvular dysfunction

1. Type I [5%] : Subarterial

(outlet, subpulmonic, supracristal or infundibular)

2. Type II [75-80%] : Perimembranous (subaortic)

3. Type III [9%] : Inlet (AV canal)– Type IV [10%] : Muscular (Trabacular)

Anterior (marginal)

Swiss cheese type

Supracristal VSDs – Clinical(subpulmonary, subarterial, conal defects)

• 5-7% of all VSDs in West, 30% in Far East

• Defect within outlet (conal) septum and part of its rim is formed by aortic and pulm. Annulus.

• Associated Aortic Incompetence Murmur due to aortic leaflet prolapse

• Systolic murmur heard over pulmonic area that radiates to the Lt. clavicle (similar to PS)

Perimembranous - Supracristal

Inlet (or AV canal) VSDs

• 5-8 % of all VSDs

• Posterior and inferior to the perimembranous defect

• Beneath the septal leaf let of tricuspid valve

Muscular VSDs

• Representing 10% of isolated VSDs• Completely surrounded by muscle• May be in the

– inlet, – trabecular, or – outlet portion of the interventricular septum.

• Can be multiple, and have been described as having a "swiss-cheese" appearance.

• Depicted by careful echocardiography, particularly with color doppler imaging

Muscular VSDs - Clinical

• High frequency systolic murmur which ends prior to systole

Clinical Manifestations

History1. With a small VSD, the patient is asymptomatic with

normal growth and development.

2. With a moderate to large VSD, delayed growth and development, decreased exercise tolerance, repeated pulmonary infections, and CHF are relatively common during infancy.

3. With long-standing pulmonary hypertension, a history of cyanosis and a decreased level of activitymay be present.

Clinical Manifestations

Physical ExaminationSmall VSD : Holosystolic murmur

Well developed and acyanotic

Clinical ManifestationsPhysical Examination

Large VSD : – Holosystolic murmur– systolic thrill may be present at the lower left sternal border.

Precordial bulge and hyperactivity are present with a large-shunt VSD.

Size of the Defect

1. Large : (nonrestrictive) >10mm– Diameter of the defect equal to diameter of the aortic orifice; – RV systolic pressure is systemic, & – Degree of L-> R shunt depends on pulmonary vascular

resistance

2. Moderate (restrictive) 5 - 10mm• Diameter of the defect < that of aortic orifice• RV pressure is half to 2/3 systemic & • L-R shunt is > 2:1

3. Small (restrictive) < 5 mm• Diameter of the defect < 1/3 the size of aortic orifice• RV pressure is normal & • L-R shunt is < 2:1

Electrocardiography

1. With a small VSD, the ECG is normal.

2. With a moderate VSD, left ventricular hypertrophy (LVH) and occasional left atrial hypertrophy (LAH) may be seen.

3. With a large defect, the ECG shows biventricular hypertrophy (BVH) with or without

4. If pulmonary vascular obstructive disease develops, the ECG shows RVH only.

Electrocardiography

•Biventricular hypertrophy with left dominance.•Note that V2 and V4 are in 1/2 standardization

X-Ray

• Heart size is moderately increased, with enlargement on both sides. • Pulmonary vascular markings are increased, with a prominent main pulmonary artery

segment.• In pulmonary vascular obstructive disease (PVOD), the main PA and the hilar PAs enlarge

noticeably, but the peripheral lung fields are ischemic

Echocardiogram

• Standard parasternal long-axis viewThe ventricular septum consists of (from the aortic valve toward the

apex) 1. the infracristal outlet (Inf-C outlet)

2. septum (the VSD of TOF is seen here) and

3. the trabecular (middle and apical) septum.

Echocardiogram

• Parasternal RVOT viewThe ventricular septum consists of (from the aortic valve toward the apex) 1. supracristal outlet (Sup-C outlet) septum and

2. the trabecular septum

Echocardiogram

• Parasternal short-axis view showing the aortic valve1. the membranous septum is toward the 10 o'clock direction,

2. the infracristal outlet septum at the 12 o'clock direction, and

3. the supracristal outlet septum immediately adjacent to the pulmonary valve

Echocardiogram

• Parasternal short-axis view showing the aortic valve1. the membranous septum is toward the 10 o'clock direction,

2. the infracristal outlet septum at the 12 o'clock direction, and

3. the supracristal outlet septum immediately adjacent to the pulmonary valve

Echocardiogram

• Parasternal short-axis - The ventricular septum at the mitral valve

1. the posterior muscular septum, is the inlet (INLET) septum.

Echocardiogram

• Parasternal short-axis - The ventricular septum at at the papillary muscle (B3) is all trabecular septum, so that one can easily classify the defect into

1. Anterior (ANT),

2. middle (MID), and

3. posterior (POST) trabecular defects

Echocardiogram

• apical four-chamber view showing the coronary sinus (C1),

• the ventricular septum is the posterior (POST) trabecular septum.

In the standard apical four-chamber view, the membranous septum is not visible

Echocardiogram

In the apical four-chamber view showing both AV valves (C2),

1. the septum immediately beneath the tricuspid valve is the inlet septum (INLET) and the remainder is the middle and apical septa.

2. The thin septum between the insertion of the mitral and tricuspid valves is the atrioventricular septum (C2), a defect that can result in an LV-to-RA shunt.

Echocardiogram• In the apical “five-chamber” view (C3), • the membranous (MEMB) septum is seen beneath the

aortic valve and below it is the it is theinfracristal outlet (Inf-C outlet) septum.

Echocardiogram• Subcostal four-chamber view (D1)• The ventricular septum seen similar to the apical

four-chamber view (C2).

Echocardiogram• Subcostal four-chamber view• With anterior angulation of the horizontal

transducer, the LVOT is seen (D2) and the septum seen here is similar to the apical five-chamber view (C3).

Echocardiogram• Subcostal four-chamber view• With further anterior angulation, the RVOT is seen

(D3). The superior part is the supracristal outlet (Sup-C outlet) septum and the inferior part is the anterior (ANT) trabecular septum (D3).

Echocardiogram• The subcostal short-axis view showing the

RVOT (E1) is orthogonal to the standard subcostal four-chamber view and is an important view for evaluating the site and size of a VSD.

• In this view both supracristal outlet (Sup-C outlet) and infracristal outlet (Inf-C outlet) septa (in that order) are seen beneath the pulmonary valve and the trabecular septum (ANT and POST) is seen apical ward.

• The ventricular septum seen at the papillary muscle (E2) is all trabecular septum and is similar to the parasternal short-axis view (B3).

Echocardiogram

Echocardiogram• The membranous septum is closely related to the

aortic valve. • In the apical and subcostal “five-chamber” views,

it is seen in the LV outflow tract just under the aortic valve

• In the parasternal short-axis view at the level of aortic valve, it is seen adjacent to the tricuspid valve

• These are the best views to confirm the membranous VSD.

Echocardiogram

• Two-dimensional echocardiogram showing membranous ventricular septal defect (VSD). The membranous VSD

• is seen underneath the aortic valve in the left ventricular outflow tract (in the apical “five-chamber” view).

Natural History1. Spontaneous closure occurs in 30% to 40% of patients with

membranous VSDs and muscular VSDs during the first 6 months of life. It occurs more frequently in small defects. These VSDs do not become bigger with age; rather, they decrease in size. However, inlet defects and outlet (infundibular) defects do not become smaller or close spontaneously.

2. CHF develops in infants with large VSDs but usually not until 6 to 8 weeks of age.

3. Pulmonary vascular obstructive disease may begin to develop as early as 6 to 12 months of age in patients with large VSDs, but the resulting right-to-left shunt usually does not develop until the teenage years.

4. Infundibular stenosis may develop in some infants with large defects and result in a decrease in the magnitude of the left-to-right shunt (i.e., acyanotic TOF), with an occasional occurrence of a right-to-left shunt.

5. Infective endocarditis rarely occurs.

Atrial Septal Defect

• An atrial septal defect (ASD) is an An atrial septal defect (ASD) is an opening in the atrial septum allowing opening in the atrial septum allowing blood to shunt between left and right blood to shunt between left and right atria. atria.

• First described by Rokitansky in First described by Rokitansky in 18751875

• Clinical features first described by Clinical features first described by Bedford, Pepp and Parkinson in Bedford, Pepp and Parkinson in 19411941

Atrial Septal Defects

1. Ostium Secundum: [most common CHD in adults]Defect involves tissue of the septum primum at or around the area of the foramen ovale

2. Sinus Venosus (sinoseptal defects):Defects of the embryological origin of the junction of superior and inferior vena cava into the right atriumThe latter defects are often associated with partial anomalous pulmonary venous return.

3. Ostium Primum:Defect involves endocardial cushion tissue.

4. Raghib typeAbsent coronary sinus with Left SVC connection to left atrium.

5. Multiple coalescent defects

Types:

Classification of ASD

Classification of ASDs

• Mild : Pulm. Art. / Aortic flow ratio < 2:1

(QP – QS Ratio)

• Mod. to Large :

Pulm. Art. / Aortic flow ratio > 2:1

Depending upon Shunt Ratio :

Classification of ASDs

• Small : ASD area < 1 cm2

(Asymptomatic)

• Moderate : ASD area 1 - 3 cm2 (Asymptomatic or mild symptoms

due to thromboembolism, arrhythmias)

• Large : ASD area > 3 cm2 (Symptomatic, RV overload,

thromboembolism, arrhythmias)

Depending upon Size :

Hemodynamics

• Magnitude of L -> R shunt depends upon

- Size of the defect

- Relative compliance of the ventricles

- Relative resistance in both the pulmonary and systemic circulations

RV Conduction delay (rSR’ pattern)

Sino-septal defects

• Involve the area of the atrial septum derived from the sinus venosus.

• Most commonly this includes defects that occur at the junction of the superior vena cava and the right atrium,

• The right upper pulmonary veins typically enter the left atrium superiorly and just to the left of the atrial septum and sinus venosus region. When a defect of the superior sinus venosus exists, the flow from these veins may be directed toward the right atrium through the sinus venosus defect.

• Alternatively, these veins may truly be anomalous in their drainage and enter the right atrium directly. These defects are known as sinus venosus defects.

AVSD

• Atrioventricular septal defects (AVSD) result from abnormal development of the membranous and muscular atrioventricular septum. Depending on severity, the defect can be classified as complete or partial.

• The ventricular septal defect is located at the 'inlet' portion of the ventricle and the atrial septal defect occurs as an ostium primum type (a deficiency of the septum primum in its inferior and anterior aspect).

• AVSD can accompany other complex congenital heart disorders.

ASDs – Echocardiogram• Secundum atrial defects are well defined on echo from

subcostal view and the defect can be sized. • With use of color Doppler flow mapping, a qualitative

assessment of shunting and its direction can be obtained. • The four-chamber apical view can assess the shunt-

volume effects on size and wall thickness of the right ventricle, but is less reliable for accurately measuring the defect.

• The parasternal ventricular short axis view may show a flattened interventricular septum during diastole due to right ventricular volume overload.

• TEE can be extremely useful in diagnosis and management since it accurately displays the region of the atrial fossa where the secundum defects occur and can determine eligibility for catheter-guided closure.

Course & Prognosis

• Most common CHD in adults (OS Type)• Patients can pass through 3rd or 4th decade

with little hardship• Life expectancy is shortened• Recurrent respiratory infections due to shunt• Effort intolerance and fatigue common• Infective endocarditis rare – • Lack of jet lesion• Absence of turbulence because of low

velocity of flow across defect

Course & Prognosis

• Older patients – deteriorate rapidly• Degeneration of coronary artery, systemic

hypertension leading to LVF• Atrial arrhythmias : fibrillation, flutter, PAT• Eisenmenger’s syndrome (seldom < 20 yrs)• 5% infants with large ASDs succumb as

early as 1st week of life• Some symptomatic patients may improve

due to spontaneous closure

• Surgical or transcatheter device closure is advised for all symptomatic patients and also for asymptomatic patients with a Qp : Qs ratio of at least 2 : 1.

Patent Ductus Arteriosus

Types:Types:

1. Large PDA : significant LV overload, CHF, severe PAH, murmur unlikely to be loud or continuous

2. Moderate PDA : some Lt heart overload, mild to moderate PAH, no/mild CHF, murmur is continuous

3. Small PDA : minimal or no Lt heart overload, no PAH or CHF, murmur may be continuous or only systolic

4. Silent PDA : No murmur, no PAH. Diagnosed only on echo Doppler

PDA - Anatomy

Clinical Features

1. Tachycardia and tachypnea - with CHF.

2. Bounding peripheral pulses with wide pulse pressure

3. The precordium is hyperactive.

4. A systolic thrill may be present at the upper left sternal border

5. A grade 1 to 4/6 continuous (“machinery”) murmur is best audible at the left infraclavicular area or upper left sternal border.

6. If pulmonary vascular obstructive disease develops, a right-to-left ductal shunt results in cyanosis only in the lower half of the body (i.e., differential cyanosis).

ECG

• A normal ECG or LVH is seen with small to moderate PDA.

• BVH is seen with large PDA.

• If pulmonary vascular obstructive disease develops, RVH is present.

X-Ray

1. Chest x-ray films may be normal with a small-shunt PDA.

2. Cardiomegaly of varying degrees occurs in moderate- to large-shunt PDA with enlargement of the LA, LV, and ascending aorta. Pulmonary vascular markings are increased.

3. With pulmonary vascular obstructive disease, the heart size becomes normal, with a marked prominence of the PA segment and hilar vessels.

PDA

Diagnostic criteria• Lumen of the

vessel visualized along the entire length.

• LAE• LV dilatation

PDA - Hemodynamics

PDA - Echo

Note: The Shunt going from below upwards in the pulmonary artery

PDA - Echo

• Parasternal short-axis view demonstrating patent ductus arteriosus (PDA) that connects the main pulmonary artery (MPA) and the descending aorta

Natural History of PDA

• Unlike PDA of prematures spontaneous closure of PDA does not occur. PDA of term are due to structural abnormality of ductal smooth muscle.

• PVOD, CHF or recurrent pneumonia.

• Infective endocarditis may occur

• Rarely, aneurysm of PDA may develop and possibly rupture in adult life.

DD1. Coronary arteriovenous fistula

2. Systemic arteriovenous fistula

3. Pulmonary arteriovenous fistula

4. Venous hum

5. Collaterals in COA

6. VSD with AR

7. Absence of the pulmonary valve

8. Persistent truncus arteriosus

9. Aortopulmonary septal defect (aortopulmonary window):

10. Peripheral PA stenosis

11. Ruptured sinus of Valsalva aneurysm:

12. Total anomalous pulmonary venous return (TAPVR) draining into the RA:

Management - Medical

1. Indomethacin is ineffective in term infants with PDA and should not be used.

2. Standard anticongestive measures with digoxin and diuretics are indicated when CHF develops.

3. No exercise restriction is needed in the absence of pulmonary hypertension.

4. Prophylaxis for bacterial endocarditis is indicated when indications arise.

Management - Nonsugical ClosureSmall ductus less than 4 mm in diameter are closed by

Gianturco stainless coils and larger ones by an Amplatzer PDA device.

Advantages– no need for general anesthesia,

– Shorter hospital stay and convalescent period,

– Elimination of a thoracotomy scar

Disadvantages– residual leaks, – PA coil embolization, – hemolysis, – left PA stenosis, – aortic occlusion with the Amplatzer device, and – femoral vessel occlusion.

Timing of Closure

• Large/moderate PDA with CHF, PAH – Early closure by 3-6 mo. (Class I)

• Moderate PDA, no CHF, PAH : 6 mo.- 1 yr – (Class I). If failure to thrive – closure can be earlier (class II)

• Small PDA – At 12 to 18 mo. (class I)• Silent PDA – Closure not recommended (class

III)

Coarctation of Aorta (COA)

• 8- 10 % of all CHD.

• M:F = 2:1. 30% of Turners Syndrome.

• 85% of COA have bicuspid valve.

• Poor feeding, dyspnea & poor weight gain, & acute circulatory shock in first 6 weeks .

• 20-30% of COA develop CHF by 3 months

Coarctation of the aorta

Diagnostic findingAortic lumen is narrowed, typically distal to the left

subclavian artery.Hypoplastic aortic archPost stenotic dilatation of

the aorta.Bicuspid aortic valve.Doppler will show the

severity of obstruction.

Coarctation of the aorta - Hemodynamics

Coarctation of the aorta - Types

Natural History of COA

• Bicuspid valve may cause stenosis or regurgitation with age.

• SBE may occur on either aortic valve or on coarctation.

• LV failure, rupture of aorta, ICH, hypertensive encephalopathy may develop during childhood.

Coractation of Aorta

• Diagnosis :– Absent femoral pulses– BP in upper and lower limbs– X- Ray chest– Echo– CT angiography– MRI

Coractation of Aorta

• Timing of Intervention :– With LVH / CHF or severe upper limb hypertension :

Immediate intervention (Class I)– Normal LVH, no CHF & mild upper limb

hypertension : Intervention beyond 3-6 mo. Age (Class IIa)

– No hypertension, no heart failure, normal ventricular function : Intervention at 1-2 yrs of age. (Class IIa)

– Intervention is not indicated if Doppler gradient across coarct segment < 20 mm Hg with normal LV function. (Class III)

Coractation of Aorta

• Mode of Intervention :– Balloon dilatation of surgery for children> 6 mo. Age– Surgical repair for infants < 6 mo. Age– Balloon dilatation with stent development in children >

10 yrs age– Elective endovascular stenting of aorta is

contraindicated for children < 10 yrs of age (class III)

Tetrology of Fallot

Infective Endocarditis Prophylaxis

• Every child with CHD must be advised to maintain good oral hygiene and regular dental check up

• Unrepaired CCHDs are high risk conditions for IE. So prophylaxis is mandatory

• ASD (secundum type) and valvular PS are low risk conditions for IE – prophylaxis not recommended

• Other acyanotic CHDs including bicuspid aortic valve are moderate risk & prophylaxis is recommended

• Repaired CHDs with prosthetic material need prophylaxis for first 6 mo. after procedure

• Device placement by transcatheter route also require prophylaxis for the first 6 mo.