Congenital heart diseases Flashcards
Etiology:
genetic and environmental factors
Embriology
1) Neural crest cells are migrating at the truncal and bulbar ridge,
which grow in a spiral
fashion and fuse to form the aorticopulmonary septum.
2) The heart continue to curve, and atria get a posterior and superior position comparing with ventricles.
Cardiac septation is the next step by formation of a fibrous atrioventricular ring and the endocardial cushion resulting two channels – right and left.
The next step is the formation of the atrioventricular valve -week 7/8.
Most common congenital malformation
Ventricular septal defect
Clinical examination
– Inspection: cyanosis, clubbing fingers
– Palpation: thrill, femoral, radial pulse, liver dimensions
– Auscultation: cardiac, extracardiac
– BP measuring
Investigations
– Radiology
▪ Cardiomegaly: CTI > 0.6
▪ Particular shapes
▪ Pulmonary vascular system
– ECG: RVH, LVH, BVH
– Ecocardiography
Cyanotic heart disease
Decreased pulmonary flow
- Tetralogy of Fallot
- Tricuspid atresia
- Other univentricular hole with pulmonary stenosis
Increased pulmonary flow
- Transportation of great arteries
- Total anomalous pulmonary venous return.
Acyanotic heart disease
L - > R shunt lesions
- VSD
- ASD
A-VSD
PDA
Obstructive lesions
- Aortic stenosis
- Pulmonary valve stenosis
- Coarctation of Aorta
Without cyanosis
- ASD
- VSD
- AVSD
- PDA
- CoAo
- Cong Mi St
- Ao St
- P St
- Endomiocardial
fibroelastosis
Cyanosis
- TGA
- HLHS
- Tetralogy of Fallot
- Abnormal pulmonary
connections - Pulmonary atresia
- Tricuspid atresia
- Arterial Trunk
- Ebstein anomaly
- Univentricular heart
Physiopathological classification:
– Intra/extracardiac shunts:
ASD, VSD, AVSD,PDA
Physiopathological classification
Conotrunkal anomalies:
Increased pulmonary flow: TGA, PAT
Decreased pulmonary flow: TOF, TA, PA
Obstructive lessions:
Left: Mi St, HLHS, Ao S, Co Ao
▪ R: TA, PA
ASD
◼ Anatomical classification:
◼ ostium secundum defect;
◼ ostium primum defect;
◼ sinus venosus defects;
◼ defect of the coronary sinus.
◼ Hemodinamics
– Left to right shunt – with PHT with increased vascular resistance
– Right cavities dilation
ASD – clinical manifestations
◼ Asymptomatic
◼ Repeated respiratory infections (increased pulmonary flow)
◼ Systolic murmur of low intensity or absent - sweet,
ejection, protomezosistolic maximum in the II-III
intercostal space (relative pulmonary valve stenosis).
◼ Strong 1st sound
◼ Fixed duplicated 2nd sound
ASD - paraclinic
Chest – X Rays
– pulmonary hipervascularization
– moderated cardiomegaly (dilatation of the RA, RV, and PA)
◼ ECG
- Right ax deviation + 90/+ 180
- RVH or RBBB with pattern rSR‘ in V1
◼ Eco
- The position and size of the defect
- Evaluation of the ratio Systemic/pulmonary flow
- Right ventricular dilatation
- Abnormal ventricular septum movement.
ASD - management
◼ Spontaneous closure in 40% of cases in the first 4
years of life
◼ The small defects closure rate is > 80% in the first 18
months of life
◼ If the defect is large and it is not closed, complications
can occur:
– Pulmonary hypertension
– Cyanosis
– Heart failure
– Atrial arrhythmias - in the third - fourth decade of life
– Stroke by paradoxical embolism
ASD - treatment
Medical + surgical
◼ Medical:
- No need for fluid restriction nor endocarditis prophylaxis
◼ Surgical:
– in all situations where blood flow ratio P/S ≥1.5; at 3-5 years old
– Surgical mortality <1%
– Open heart surgery - closing the hole with a patch of Dacron/Goretex
– CI: elevated PVR (>10 units/m2)
ASD treatment
Intervational + complications
Interventional
Closing by an occluder consisting of two discs, 1.5-2 times the size
of the defect
◼ Complications
- Especially in the sinus venosus atrial septal defect - atrial or nodal
disorders in 7-20%
- Rarely sick sinus syndrome - pacemaker
- Residual shunt especially in the interventional method
VSD
Prevalence + Types
Prevalence: 20-25%, except for those
included in the cyanotic CHD
Types of VSD
- perimembranous - 70%
- musclular - 5-20%
- subarterial (doubly committed)
VSD - hemodynamics
◼ Shunt left - right which in time will increase vascular
resistance with pulmonary hypertension
◼ Hemodynamic consequences
depend on the size of the
defect and pulmonary vascular
resistance and systemic ratio
◼ Dilation and hypertrophy of the
left cavities (LA, LV)
◼ If the shunt is great - PHT -
biventricular hypertrophy, may
reverse the shunt from right to
left
DSV – clinical findings
SMALL
◼ Normal physical development, asymptomatic.
◼ Holosystolic murmur 3 - 5/6, sp IV-V auscultation, “like a steam”
In 30-50% of cases the defect closes spontaneously
DSV - clinical findings
LARGE
◼ Delate in growth and development occurs early
◼ Frequent respiratory infections, heart failure,
◼ Respiratory signs:
tachypnea,
dyspnea with cough,
systolic murmur,
heard throughout the chest area, “the wheel spokes”
◼ Clinic: shortness of breath, difficulty in feeding, chest deformity, sweating, hepatomegaly.
VSD
Investigations
◼ Chest X ray
- Cardiomegaly
– Increased pulmonary flow
◼ ECG:
- small VSD: normal
- Moderate VSD: LVH, LAD
- Large VSD: biventricular hypertrophy, LAD
- Pulmonary vascular obstructive disease: RVH
◼ Eco
– The position and size of VSD
– Size of the LA, LV - indirect indicators of shunting
– Doppler signal at the PA level, and tricuspid regurgitation
VSD management
◼ Spontaneous closure in 30-40% of VSD, most frequently
those small, muscular, and early in life
◼ The large defects tend to become smaller with age
The inlet or infundibular defects do not close spontaneously nor diminish
◼ CHF occurs in children with large VSD but not before 6-8
weeks of age
◼ Pulmonary vascular obstructive disease start to emerge
at 6 to 12 months of life in patients with large VSD but
reversal of the shunt appears in the second decade of life
◼ Infective endocarditis is rare
VSD -treatment
◼ Medical
Treatment with digitalis and diuretics for CHF
◼ No effort limitation is necessary in the absence
of PHT
◼ Maintaining good dental hygiene and
prevention of endocarditis
VSD
Surgical Procedures
Palliative - PA banding, rarely – for associated lessions
◼ Direct closure –cardiopulmonary bypass with atrial approach, preferable, than right ventriculotomy
– Indications and timing
▪ Qp/Qs > 2,
– At 12-18 months in those who respond to medical treatment.
– At 2-4 years in asymptomatics.
– Having HF or growth deficiency – nonresponsive to medical treatment even as infants.
▪ If the PVR is increasing as soon as possible
– Contraindications: RVP/RVS ≥ 0.5 or vascular obstructive pulmonary disease with right to left shunt.
◼ Postoperatively – cardiac blocks, residual shunt
Patent Ductus Arteriosus
(PDA)
◼ Ductal closure occurs on the aortic side
because of
the higher oxygen tension in the aorta.
◼ Physiologic closure is evident by about 16 hours of life; however, anatomic closure may not be complete for 2–3 weeks.
PDA epidemiology
◼ PDA is common in premature infants;
patency may remain for some months after birth.
◼ In the presence of hypoxia, the DA tends to remain open – a continuous “machinery murmur” is heard over the DA.
PDA – clinical manifestations
◼ Asymptomatic – small PDA
◼ Heart failure – large PDA
◼ Continuous murmur: 1-4/6 left infraclavicular
PCA
◼ ECG: like VSD
◼ Rx P: like VSD
◼ 2D and Doppler echocardiography– the
magnitude of the shunt, hemodynamic
impact, sPAP
PDA - evolution
– Large shunt
▪ HF, recurrent pneumonia, PHT with vascular
obstruction pulmonary disease
– Spontaneous closure - the term newborn -
more frequent (about 30%) if the diameter of the AD is <2.5 mm in the 3rd day of life
PDA - treatment
◼ Medical
– In the absence of PHT physical exercises are not forbidden
– Indomethacin, ineffective in term newborn, is effective only in premature, if taken in the first 10-14 days of life from 0.1 to 0.25 mg/kc/D, 12 hours, 3 doses,
– IV endocarditis prophylaxis
– Large PCA - HF - diuretics, fluid restriction
– Catheterization – device closure: coil, Amplazer - Good results for PCA diameter <2.5 mm
– Surgical - for PCA> 3 mm - ligation via thoracotomy
posterolaterally without bypass. Surgical mortality <1%
AVSD
◼ A large left-to-right shunt results in severe
congestive heart failure and pulmonary hypertensive vascular changes that may appear in the first year of life.
◼ Conduction abnormalities with left axis deviation and RV hypertrophy are present.
AVSD may accompany other defects, including visceral asymmetry and poly/asplenia syndromes.
AVSD
Epidemiology and Investigations
◼ 30% of the defects apear in children with Down sd
◼ 2 forms: complet (ASD I, VSD inlet, cleft MiV, cleft
TricV) and partial (without VSD)
◼ Shunt left/right – PHT
◼ Holosystolic murmur 3-4/6
◼ ECG: ax qrs – superior (-40→-150), characteristic,
RVH, LVH, BAV gr I
◼ Chest X-Rays: cardiomegaly+increased vasculary flow
◼ Echo - dgn
Coarctation of the Aorta
◼ Coarctation may be preductal or ductal
◼ In the preductal type there is a tubular hypoplasia of the
aortic arch. Symptoms become manifest early in
infancy.
◼ The ductal type consists of a localized constriction of the
aorta in the region of the closure of the ductus arteriosus.
◼ Symptoms in this type usually are delayed until adolescence or later.
CoAo - paraclinic
◼ ECG:
– In the first 2 years of life – RVH, RBBB
– After 2 years - LVH
◼ Chest X Rays:
– cardiomegaly, venous congestion
– Collaterals: mamar, intercostal –continuous
murmur
◼ Echo: place, expansion, associated defects
Doppler aspect in “sawtooth”
CoAo Treatment
◼ Medical
– HF: positive inotropics– catecolamins; diuretics, oxygen
– Continuous PEV with PGE1 – for reopening of the duct
◼ Balloon angioplasty – controversial – 50%
recoarct
◼ Stent implantation: bare stent/covered stent (>20 kg)
◼ Surgery:
– Mortality – 5%
◼ Post operator:
– EB prophylaxis
– Reevaluation in 6 months
Complete Transposition of Great Vessels (TGA)
◼ Complete TGA accounts for 6% of all CHD
◼ The coronary arteries arise from the sinuses of the aortic valve and thus receive blood from the RV, resulting in a
desaturated blood supply and ischemia of the myocardium.
◼ Severe pulmonary vascular changes occur
in 40% of patients by 1 year of age.
TGA – “parallel circulations”
◼To be compatible with life there must be an exchange of blood between the two circulations, through either a patent foramen ovale, an ASD, a VSD, or a PDA.
TGA - clinically
◼ Cyanosis
◼ HF signs (dyspnea, fatigability
◼ Severe hypoxemia non-responsive to oxygen
TGA - paraclinic
◼ ECG
– Right ax deviation, RVH.
– If there is a large VSD - signs of LVH
◼ Chest X -Rays
– Cardiomegaly, increased pulmonary flow
– Appearance of “egg lying on the diaphragm” with a narrowed mediastinum
– Echo – diagnostic – aspect of “two circles”
TGA - treatment
◼ Medical
- treatment of hypoglicemia/acidosis/hypocalcemia
- PGE1 IV- reopening duct
- oxygen
◼ Interventional
– Septostomie atrial balloon Rashkind
– Treatment with digitalis and diuretics for HF
◼ Surgical
Switch
– atrial - Senning - many post-op complications
– Ventricular - Rastelli
– Arterial - of choice.
Complications: IAO, coronary artery disease
Tetralogy of Fallot (TOF)
◼ TOF is the most common form of
cyanotic CHD, asround 10% of all
CHD.
◼ The components of tetralogy are
– Infundibular pulmonic stenosis,
- VSD,
- aortic valve dextroposition,
- RV hypertrophy.
◼ However, it is the result of a single
embryologic defect due to malalignment with anterior
deviation of the conus (infundibular) septum, which
creates infundibular narrowing, a perimembranous VSD, and a dextroposition with overriding of the aorta above the VSD.
◼ Associated anomalies include ASD (pentalogy of Fallot), right aortic arch, and absence of the DA.
Tetralogia Fallot - clinic
◼ Central cyanosis
◼ Hippocratic fingers
◼ Dyspnea, anoxic crises
◼ Systolic murmur, grd 3-5/6 – VSD, P St
◼ Complications:
– Cerebral Abscess, stroke, bacterial
endocardites
Tetralogia Fallot -
paraclinic
◼ ECG
– RH deviation of the ax, RVH
◼ Rx
◼ A “coeur en sabot” (boot-shaped
heart) appearance due to RV hypertrophy and an upward tilting of the LV apex is seen by X-ray.
Decreased pulmonary blood flow results in the clear appearance of the chest radiograph because of decreased vascular markings.
◼ Right aortic arch in 25% of the cases
◼ Echo: dgn
Tetralogia Fallot - treatment
◼ Medical
– Anoxic crises – morphine, propranolol, oxygen, position
– Propranolol po, 2-4 mg/kg/day
– Bacterial endocarditis prophylaxis
– Treatment of the iron deficiency
◼ Surgical
– Palliative procedures - systemic-pulmonary
shunts
- Blalock Taussig
(anastomosis between the subclavian artery and ipsilateral pulmonary artery)
– Correction - usually at 3-4 months/asymptomatic - 3-24 months
VSD Closure with Patch, infundibular P St resection/widening
ABNORMALITIES OF POSITION AND SITUS
◼ Dextroposition describes a heart displaced to the right
side of the thorax with a left-sided apex
◼ Dextrocardia implies that the heart is
located in the right chest with a right-sided apex.
PERSISTENT LEFT SUPERIOR VENA CAVA (PLSVC)
◼ This can be an isolated condition or
associated with poly/asplenia
◼ When present it drains into the
coronary sinus, which is large and dilated.
ECTOPIA CORDIS
◼ The heart is located partially or totally outside the chest
◼ Thoracoabdominal or abdominal ectopia is associated with a defect in the lower sternum, diaphragm, and abdominal wall with omphalocele and heart defects (pentalogy of Cantrell)
VASCULAR RINGS
These include
– double aortic arch due to persistence of the
right 4th branched arch
– an anomalous right subclavian artery vessel coursing behind the trachea and esophagus
