Download 1-acyanotic congental heart diseases

CONGENITAL HEART
DISEASE.
Anatomy of the Heart
Figure 12.2
Epidemiology
• Prevalence:0.5-0.8% of live births (8/1000).Leading
cause ofdeath in children with CHD.
• Etiology:Unknown,multifactorial inheritance,genetic
factors implicated,high incidence in first degree relatives.
• 3% have a single gene defect,13% have associated
chromosomal abnormalities.
• 2-4% are associated with environmental or maternal
conditions & teratogenic influences.
• Gender differences:ASD,VSD,PDA & Pulmonic stenosis
more common in girls,left sided lesions in boys.
Recurrence of CHD
Congenital Heart Disease: Etiologies
Most cases (70-80%) are “multifactorial”
The Recurrence Risk with:
- 1 sib with CHD: 2-4%
- 2 sibs with CHD: 6-12%
- Mother with CHD:6-12%
- Father with CHD: 2-4%
In 1/2 of these families the same defect recurs.
Common acyanotic lesions
*Ventricular septal defects
*Atrial septal defects
*Atrio-ventricular septal defects
*Patent ductus arteriosus
*Truncus arteriosus
*Pulmonary stenosis
*Aortic stenosis
*Mitral stenosis/incompetence
*Coarctation of aorta
*Tricuspid regurgitation
Common Cyanotic Lesions
Decreased flow
1. Tetralogy of Fallot
2. Tricuspid Atresia
3. Severe Pulmonic Stenosis
4. Ebstein’s anamoly
Increased Flow
5. Transposition of great vessles
6. VSD with pulmonary atresia
Common Lesions producing
cyanosis
7. Truncus Arteriosus
8. Hypoplastic left heart
9. Single ventricle
10. TAPVR with infradiaphragmatic
obstruction
Etiology
• Congenital Heart Disease:
Etiologies
• 6-12% have gross
chromosomal anomalies
• - Trisomy 21 (40% have CHD):
AV canal
• - Trisomy 18 (100% have
CHD): VSD, PS
• - Trisomy 13- 15: VSD, ASD,
TGV
• - XO (Turner): Coarc, AS, VSD
• - XXY (Klinefelter): Ebstein,
Tetralogy
Prevalence
• Acquired
• Congenital
• Cyanotic: 22%
• Acyanotic: 68%
–
–
–
–
–
–
VSD
ASD
PDA
TOF
PS
AS
25%
6%
6%
5%
5%
5%
–
–
–
–
Kawasaki disease
Rheumatic
Tubercular
Collagen
Ceylon Med J 2001 Sep; 46 (3): 96-8; Indian J Pediatr. 2001 Aug;68
(8):757-7
Fetal Physiology
• Right-to-left shunting at atrial level
(PFO) and at arterial level (ductus
arteriosus)
• High pulmonary vascular resistance
• Little pulmonary blood flow
• Ventricles work in parallel
Transition From the Fetal
Circulation
• Pulmonary vascular resistance falls
• Ductus venosus and ductus
arteriosus close
• Right-to-left shunting through
foramen ovale ceases
Timing of these events determines
the timing of presentation of
congenital heart defects
Cyanosis: is it a cardiac cause or
lung cause
• Hyperoxia test
– Neonates with cyanotic congenital heart
disease usually do not have significantly
raised arterial Pao2 during administration of
100% oxygen.
Ventricular Defect
• Small VSD
– Asymptomatic
– A loud, harsh, or
blowing holosystolic
murmur.
• Large VSD
– dyspnea, feeding
difficulties, poor
growth, profuse
perspiration, recurrent
pulmonary infections,
and cardiac failure in
early infancy.
Syndromes associated with this condition
80%
VSD: ECG is normal but may show right ventricular
hypertrophy, if present indicates defect is large and
presence of pulmonary hypertension or pulmonry
stenosis
Ventricular Septal Defect (VSD)
Small VSDs, the chest radiograph is usually normal
Large VSD: The presence of right ventricular hypertrophy, olegeimic lung fields
(pulmonary hypertension or an associated pulmonic stenosis), gross
cardiomegaly with prominence of both ventricles, the left atrium.
Ventricular Septal defects
• 30–50% of small defects close spontaneously,
most frequently during the 1st 2 yr of life.
• Small muscular VSDs are more likely to close
(up to 80%) than membranous VSDs are (up to
35%).
• infants with large defects have repeated
episodes of respiratory infection and heart
failure despite optimal medical management.
• Surgical repair prior to development of an
irreversible increase in pulmonary vasculalr
resistance (usually prior to the patient's second
birthday).
Investigations
• CXR:cardiomegaly,enlarged LA&LV.
• ECG:extreme lt axis is
charecteristic,biventricular hypertrophy.
• ECHO:chamber size & pressures.
• Cardiac catheter:O2 content,PA pressure,size
& no of defects.
• Treatment:Endocarditis
prophylaxis,digoxin,diuretics.
• Surgical closure before pulmonary vascular
changes become irreversible.
ATRIAL SEPTAL DEFECT.
•
•
•
•
Sinus venosus defect:high in the septum.
Ostium secundum defect:midseptum.
Ostium primum defect:low in the septum.
Pathophysiology:L-R shunt-increased flow
across Rt heart-RV & PA enlargement.
• Clinical features:asymptomatic,slow wt
gain,frequent LRTI.
• Diagnosis:Rt ventricular heave,systolic
murmur,fixed wide split S2.
Atrial Septal Defects: secundum
• Most common form of
ASD (fossa ovalis)
• In large defects, a
considerable shunt of
oxygenated blood flows
from the left to the right
atrium.
• Mostly asymptomatic
• The 2nd heart sound is
characteristically widely
split and fixed.
Secundum
Atrial Septal Defects:primum
• Situated in the lower portion
of the atrial septum and
overlies the mitral and
tricuspid valves. In most
instances, a cleft in the
anterior leaflet of the mitral
valve is also noted.
• Combination of a left-toright shunt across the atrial
defect and mitral
insufficiency
• C/F similar to that of an
ostium secundum ASD
Atrial Septal Defect
• Enlargement of the
right ventricle
• Enlargement of atrium
• Large pulmonary
artery
• increased pulmonary
vascularity is.
ASD primum&secondum
Investigations:
• CXR:enlarged heart & PA,increased
vascularity.
• ECG:Rt axis in secundum
defect,hallmark of primum defect is
extreme Lt axis,RVH.
• ECHO:RVH,valve anatomy,flow
direction.
• Treatment:closure during cardiac
cathetrization,surgical closure.
PATENT DUCTUS ARTERIOSUS.
• Connection between PA & descending aorta
• 10% of CHD.
• Pathophysiology:Lt-Rt shunt,reverses if
pulmonary resistance increases-RV
enlargement.If PDA is large Eissenmenger
syndrome can develop.
• Clinical features:depend on size & direction of
flow,slow growth,LRTI,SOB,cyanosis.
• Diagnosis:bounding pulse,continous
murmur,loud S2.
Patent Ductus Arteriosus
• Small defect no
symptoms.
• Large defect:
–
–
–
–
–
Wide pulse pressure
Enlarged heart
Thrill in L second IS
Continuous murmur
X-ray: prominent
pulmonary artery
with increased
vascular markings.
Investigations
• CXR:cardiomegaly,increased pul vascularity.
• ECG:Lt or biventricular hypertrophy.
• ECHO:2D visualises PDA,doppler shows
turbulance.
• Cardiac catheter:PA pressures & O2 sats.
• Treatment:Endocardial prophylaxis as long as
patent,Indomethacin.
• Surgical:ligation is curative.