Congenital Heart DiseasesIntro and classification
- About 1% of live births.
- Commoner among males but ASD and PDA are commoner among females.
Aetiology
- The aetiology is often unknown but there are recognized associations such as
–maternal rubella infection: PDA, PS, AS
–maternal alcohol abuse: septal defects
–maternal drug treatment and radiation
–genetic abnormalities: familial forms of ASD and heart blocks.
–chromosomal abnormalities: septal defects, mitral and tricuspid valve defects associated with Down’s syndrome (trisomy 21) and coarctation of aorta in Turner’s syndrome (45,XO)
Classification and evaluation
*check for syndromes if CHD detected
*this evaluation can be used to describe features too!
Atrial Septal Defect (ASD)
- Represents 1/3 of all adult congenital heart disease.
- Two-three times commoner in women than men.
Types
Pathophysiology
one missing slide
Septum Secundum Defect
Septum Primum defect
Symptoms
- Most children with ASD are asymptomatic
- Prone to chest infections
- Dyspnoea on exertion
- Tiredness
- Palpitations due to atrial arrhythmia
- Symptoms of right heart failure
- Poor growth and heart failure during infancy with large septum primum defects.
Signs
Investigations
- ECG – Right atrial dilatation, right ventricular hypertrophy. Right axis deviation is likely with septum secundum defects and left axis deviation is like with septum primum defects. RBBB.
- Chest X ray – pulmonary artery dilatation and pulmonary plethora. Right ventricular enlargement.
- Echocardiography
- Cardiac catheterization
*trans oesophageal US more clarity
Treatment
Done only when Qp/Qs is greater than 2:1
*in open heart surgery closed with piece of tissue with pericardium or artificial
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- when doing echo (even MO cardio should be able to do), focus on AV cushion and ventircles for septum primum defects. *Septum primum majority seen in downs. (but not commonest CHD in downs!!! Even septum secndum beats this) * must be able to match syndromes and commonest CHD
- any child with FTT needs to have an echo done
Patent Foramen Ovale (PFO)
- Small defect in the inter atrial septum – not a true ASD.
- Usually asymptomatic
- Paradoxical embolus may occur causing increased incidence of stroke.
- very low flow so doesnt cause pelmonary A high * not true ASD since nothing wrong with SP and SS but not fused after birth and thats the problem
Ventricular Septal Defect
- Most common congenital cardiac anomaly (1 in 500 live births).
- Small VSDs are asymptomatic and 90% closes spontaneously by the age of 10.
- There is a future risk of developing aortic regurgitation or infective endocarditis even after spontaneous closure.
Hemodynamics
- Left to right shunt (LV → RV → pulmonary artery)
- RA - normal in size
- RV dilates as does main PA, LA and LV
- A large VSD eventually causes pulmonary hypertension leading to Esenmenger’s complex.
Types
Clinical Features
Moderate VSDs produce
- Poor growth in children
- Fatigue
- Dyspnoea on exertion
Physical Signs
- Right ventricular heave
- Systolic thrill
- Pansystolic murmur - heard best at the 4th left intercostal space. Cart wheel radiation.
–Small VSDs – (maladie de Roger) loud and sometimes long systolic murmur
–Moderate VSDs - loud ‘tearing’ murmur
–Large VSDs – Soft murmur
Investigations
- ECG – Both left and right ventricular hypertrophy.
- Chest X ray – Cardiomegaly. Prominent PA.
- Echocardiography – To assess the size, location and hemodynamic effects of the VSD.
Treatment
- Infective endocarditis prophylaxis.
- Moderate and large VSD s should be repaired surgically or closed percutaneously before development of pulmonary hypertension.
- -----------------------------
- no point doing treatment after eisenmengers syndrome since all damage done. so must monitor and get it done before it develops *VSD most common CHD but in adults most common is ASD because most VSD is corrected (not died!)
Patent Ductus Arteriosus (PDA)
- More common among females
- Associations
–Maternal rubella
–Premature babies
–Prenatal hypoxaemia
–High-altitude environments
Anatomy
- In fetal life, ductus serves as a functioning connection between the pulmonary artery and aorta.
- After birth, the partial pressure of O2 rises and the reduced pulmonary vascular resistance trigger closure of the ductus.
- Ultimately, the ductus fibroses and becomes the ligamentum arteriosum.
- When it doesn’t close it is called a patent ductus arteriosus (redundant).
Hemodynamics
- High pressure aorta communicates with low pressure pulmonary artery (L → R shunt)
- Increases volume in lungs and subsequently in to LV.
- RA, RV - no change
- Main PA, pulmonary vessels, LA, LV and aorta dilate.
- Eventually develops pulmonary hypertension leading to Esenmenger’s complex.
- Clinical Features
- No symptoms until later in life.
- Large volume, collapsing pulse.
- Initially, the murmur is systolic, but as diastolic equilibration occurs, murmur becomes a classic to and fro or continuous murmur.
(Murmur best heard at left sternal edge at 2nd or 3rd interocstal spaces and radiates along sternum and pulmonary artery)
- Displace apex due to increased volume with a thrust.
Treatment
- Premature infants with persistent PDA are be treated with indomathacin, which inhibits prostaglandin synthesis and stimulates duct closure.
- Surgical or percutaneous closure should be performed early as possible when indicated and generally before the age of 5 years.
Prognosis
- Good long-term prognosis after closure of PDA.
- Uncorrected PDA - 1/3 by 40 years and 2/3 by 60 years die from heart failure, pulmonary hypertension or endocarditis.
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*go through paediatric CHD lectures as well
- first ICS is coartation of aorta
- echo can be used to monitor and wait and see (close before PH or else eisenmenger syndrome) * PDA low mortalityt might very modality
Coarctation of Aorta
More common in males (M:F = 2:1).
- Improper development of aorta at the area of patent ductus leaving a restricted lumen.
- Location: proximal, at or distal to insertion of ductus.
- Associated with Turner’s syndrome.
- Associated with bicuspid aortic valves in 80% of the cases.
Types
Depending on the location in relation to ligamentum arteriosum (duct) - preductal, periductal, postductal
Pathophysiology
- Severe obstruction to the blood flow in the descending aorta.
- Formation of collateral circulations involving peri scapular and inter costal arteries.
- Decreased renal perfusion leads to systemic hypertension, which persists even after the surgical correction.
- Rib notching occurs due to physical erosion of the undersurface of the ribs as a result of intercostal collateral circulation
Clinical features
- Headaches and nose bleeds – due to severe hypertension
- Cold legs and claudication – due to poor blood circulation in the lower limbs
- Radio-femoral delay
- Weak pulses in the lower extremities
- Mid-late systolic murmur – heard over upper precodium and back.
Investigations
- ECG – LVH
- Chest X ray – dilated aorta indented at the site of coarctation (‘figure 3’ appearance) and ‘rib notching’
- Contrast CT of aorta
Treatment
- Treatment is usually indicated if the pressure gradient across the coarctation is > 30 mmHg.
- Treatment options
–Surgical correction
–Percutaneous balloon dilatation and stenting
- Hypertension is usually resolved completely when the surgery is performed in the childhood.
- Hypertension persists in about 70% of the cases when the surgery perfomed in adulthood.
Prognosis
- Surgical correction in childhood – 25-year survival rate is 83%.
- Surgical correction in adulthood (20-40 years) – 25-year survival rate is 75%.
- If coarctation left uncorrected – only 25% of the patients survive up to 50 years.
- if coarctation must look for bicuspid aortic valve and vice versa
- rib notching because of increased collateral flow from the enlarging arteries causing rib nothing
- bruit can be heard in chest wall especially in posterior wall
Eisenmenger’s Complex
- Clinical situation where in a patient with any left to right shunt develops sufficient pulmonary vascular disease and pulmonary hypertension to produce reversal of flow and therefore a right to left shunt.
Hemodynamics
- Equalization of pressures.
- Murmur diminishes due to less shunting.
- Right ventricular ejection time diminishes permitting the pulmonary valve to close sooner and intensity of S2 increases.
- With time, pulmonary resistance increases and exceeds systemic resistance and the shunt reverses resulting in cyanosis.
Clinical Features
- Cyanosis
- Polycythemia
- Clubbing
- Syncope
- Heart failure
- Arrhythmia
- Bleeding disorders
- Haemoptysis
- Stroke
- Gout
Treatment
- Medical therapy to reduce pulmonary hypertension
–ChCh blockers: Nifidipine
–Sildenafil
–Prostaglandins
–
- Venesections
- Heart-lung transplantation or lung transplantation with surgical closure of the shunt are the only definitive treatments.
* Differiential cyanosis and stuff seen in PDA?
*all these medical management might help reduce PA hypertension but might jst change the level and hypertension develops again!
Tetralogy of Fallot
- RVOT obstruction
- VSD
- RVH
- Overriding of the aorta
- Patients are more likely to survive up to adulthood. (Without intervention, 66% survive to 1 year and 11% survive to 20 years).
- The level of RVOT obstruction may be sub valvular, valvular or supra valvular.
- Most common obstruction is sub valvular stenosis (50%) or in combination with valvular stenosis (25%).
Hemodynamics
- Due to the stenosis of the infundibulum, pulmonary flow is diminished.
- Right to left shunt through VSD.
- The overriding aorta accepts most of the RV blood.
- Diminished blood flow to the lungs and increased blood flow to the body.
Clinical Features
- Right to left shunt produces peripheral cyanosis.
- Children present with cyanotic hands and feet.
- Children squat to enhance flow back to heart to oxygenate. (it reduces peripheral resistance and LV pressure increases and increases venous return shunt reduces...but total cardiac output reduces..and it may cause collapse..but still asked to keep squat when having cyanotic spell)
- Growth retardation
- Fatigue
- Shortness of breath on exertion
- Fallot’s spells – deep cyanosis and possible syncope
- Seizures
- Clubbing – obvious after 1 year
Complications
- Strokes
- Infective endocarditis
- Sudden cardiac death
Investigations
- ECG - RVH
- Chest X ray – Large RV and small pulmonary artery (boot-shaped heart)
- Echocardiogram
- Cardiac catheterization
Treatment
Antibiotic prophylaxis.
- Fallot’s spells may need beta blockers to relieve RVOT obstruction.
- Surgical correction – possible even in infancy.
- Blalock shunt – A palliative procedure (anastomosis between subclavian artery and pulmonary artery) is performed in very young infants or premature babies to improve blood supply to lungs. *to prevent atrophy of pulmonary artery ..otherwise cant do surgery if PA size collapses
Transposition of Great Arteries
- TGA is more common during neonatal period but more like to be fatal.
- 2-3/10,000 live births (M:F = 2:1).
- 50% are associated with a VSD.
- Usually, presents at birth as a blue baby.
Treatment
- Atrial septostomy – Rashkind procedure.
- Balloon dilatation of the foramen ovale could be performed.
- Prostaglandins may be given to maintain a PDA.
- Arterial switch operation – can be performed in first two weeks of life.
- if not associated with VSD then definetly not compatible with life and then cause intra uterine death * vs TOF which doesnt cause blue baby at birth
OTHER CHDS!
Truncus Arteriosus
- Single trunk giving rise to Aorta, Pulmonary artery and Coronary arteries
- Complex defect; most commonly diagnosed in the neonatal period or early infancy.
- 99% have VSD
- Incidence is <0.5% of CHD
- Associated defects
–Right aortic Arch (33%)
–Interrupted Aortic Arch(29%)
- Significant operative morbidity & mortality
Tricuspid Atresia
- Complete agenesis of tricuspid valve.
- 3% of CHD
- 3rd most common cause of Cyanotic CHD
- An ASD is always present +/- VSD (otherwise not compatible with life!)
- Extra cardiac anomalies present in 20%
Total Anomalous Pulmonary Venous Drainage
- Various classifications and varieties
- 1-2% CHD
- Early corrective surgery is the TOC
- Atrial Septostomy is a temporary measure.
- qp/qs measures pulmonary flow..of high then shunt ... *neck arteries anatomy * PDA and eisenmengers how?