Congenital Heart Defects Flashcards
What are the congenital heart defects?
- Ventricular septal defect
- Pulmonary stenosis
- Atrial septal defect
- Persistent ductus arteriosus
- Aortic valve stenosis
- Coarctation of the aorta
- Transposition of the great arteries
- Tetralogy of Fallot
- Hypoplastic left heart syndrome
What congenital heart diseases are acyanotic?
- ASD
- VSD
- PDA
- PV stenosis
- Coarctation of the aorta
- Aortic stenosis
What congenital heart diseases are cyanotic?
- Tetralogy of Fallot
- Pulmonary atresia
- Tricuspid atresia
- Hypoplastic left heart syndrome
- Transposition of the great arteries
- Total anomalous pulmonary venous return
What is acyanotic heart disease?
Heart defects presenting without cyanosis caused by fetal heart malformation. Can lead to heart failure
What can ASD, PDA, and VSD cause?
all acyanotic heart disease
- Left to right shunt
- Oxygenated blood flows redundantly through pulmonry circulation and becomes Eisenmenger syndrome over time
Signs and symptoms of acyanotic heart disease
- Sometimes asymptomatic, can lead to heart failure, Eisenmenger syndrome
- Poor feeding/failure to thrive
- Fluid retention
- Pulmonary congestion
- Hepatomegaly
- Respiratory distress
- Elevated JVP
What is Eisenmenger syndrome?
Cyanosis, palpitations, dyspnea, chest pain, and syncope with exertion
What are 2 categories of acyanotic congenital heart disease?
Left to right shunts and outflow obstruction
What causes outflow obstruction leading to acyanotic heart disease?
- Pulmonary stenosis
- Aortic stenosis
- Coarctation of aorta
Left to right shunt lesions leading to acyanotic heart disease
- Atrial septal defect
- Ventricular septal defect
- Atrioventricular septal defect
- Patent ductus arteriosus
Hole in heart wall dividing left and right atria
Atrial septal defect
Signs and symptoms of atrial septal defect
- Fixed, split S2 and pulmonic ejection murmur (louder with age)
- Infants and children: respiratory infections, failure to thrive
- Adults (before 40): palpitations, exercise intolerance, dyspnea, fatigue
Development of the atrial septum
- Septum primum develops leaving ostium primum “first opening”
- Septum primum closes
- Ostium secundum “second opening” develops in septum primum
- Septum secundum has opening for foramen ovale
- Complete closure at birth
What are types of ASD?
- Ostium secundum - at site of foramen ovale and ostium secundum, most common, associated with fetal alcohol syndrome
- Ostium primum - at level of TV and MV endocardial cushion defect found in 25% of Down’s syndrome
Diagnosis of ASD
- Chest x ray: right heart dilation and prominent pulmonary vascularity
- Transesophageal echocardiography: visualize size and location accurately
- Right heart catheterization shows increased oxygen saturation in right atrium, right ventricle, pulmonary artery
Treatment of ASD
- Surgery
- Percutaneous surgical closure
- In asymptomatic child with hemodynamically significant defect, closure performed electively at 1-3 years before late complications of RV dysfunction and dysrhythmias occur
- Closure of moderate to large defect when child between 4 and 6 (defects >8 mm unlikely to close on own)
- Adults: surgery in cases of R ventricular enlargement, paradoxical embolism, right to left shunt
Hole in septum dividing lower two chambers of heart leading to more blood pumped into lung and pulmonary artery
Ventricular septal defect
What does increased blood pumped into lung and pulmonary artery in VSD cause?
- Heart failure
- Pulmonary HTN
- Arrhythmias
- Stroke
Development of ventricles
Membranous region grows downward and muscular ridge grows upward, they don’t match up in VSDs (majority in membranous region)
3 types of VSD
- Membranous: upper septum (MC)
- Muscular: lower septum
- Intlet: posterior portion of the V septum beneath the TV
What is the most common congenital heart disease?
VSD
What does VSD cause?
Acyanotic left to right shunt between ventricles
How is size related to treatment of VSD
- Small- moderate: 3-6 mm usually asymptomatic and 50% close spontaneously by 2
- Moderate- large: almost always have symptoms and will require surgical repair
What does increased blood volume in the right ventricle due to VSD lead to?
Pulmonary hypertension and Eisenmenger syndrome
Signs and symptoms of VSD
- Asymptomatic in utero
- At birth: holosystolic murmur (loud, high-pitched) located at lower left sternal border
- Small –> asymptomatic, murmur
- Large –> sweating, poor feeding/failure to thrive, respiratory infections, murmur plus thrill and diastolic rumble in mitral
- Signs of congestive heart failure
- Eisenmenger’s syndrome
What are signs of congestive heart failure in VSD?
- Dyspnea
- Persistent cough
- Pulmonary vascular resistance
VSD diagnostic imaging
- Chest X ray: unreliable but may indicate left atrial enlargement, right ventricular hypertrophy, left ventricular hypertrophy, or pulmonary artery enlargement
- Echocardiogram determines location and size
- MRI used if echo does not diagnose
If echo and MRI do not diagnose and individual still has pulmonary hypertension in suspected VSD, what diagnostic tool should be used?
- Cardiac catheterization
What would be seen on ECG in VSD?
Left ventricular hypertrophy, may also see right ventricular hypertrophy and left and right atrial enlargement
Treatment of VSDs
- Most small close on own
- Medical management with diuretics and higher calorie feeds for symptomatic patients
- Surgery for larger shunts by age 2 to prevent pulmonary hypertension with patch (preferred) or transcatheter closure
Indications for surgical closure of VSD
- Large VSD with medically uncontrolled symptomatology and continued FTT
- Pulmonary HTN
- Aortic insufficiency
- LA/LV dilation
Persistence of normal fetal vessel that joins the PA to the aorta, normally closes in 1st weeks of life
Patent ductus arteriosus
Risk factors for patent ductus arteriosus
Preterm infants <1500 grams and infants born at higher altitudes >10,000 ft
Females > Males
Can be associated with other defects, ie coarctation or VSD
What does ductus arteriosus become after birth?
Ligamentum arteriosum
Signs and symptoms of small PDA
- Usually asymptomatic
- Neonates: holosystolic “machine-line” murmur on auscultation
- infants, children, adults: continuous murmur
Signs and symptoms of moderate PDA
- Exercise intolerance
- Continuous murmur
- Wide systemic pulse pressure
- Displaced ventricular apex
Signs and symptoms of larger PDA
- Infants: leads to heart failure
- Children: shortness of breath, fatigability, Eisenmenger syndrome
Diagnoses of PDA
- Echocardiogram: 2D suprasternal
- CXR: normal/cardiomegaly
- ECG: left ventricular hypertrophy, left atrial enlargement
Treatment of PDA
- Small asymptomatic PDA: monitor
- Neonates (10-14 days): close PDA using prostaglandin inhibitor
- Symptomatic/large PDA during heart failure: digoxin, furosemide
- Surgery for symptomatic moderate/large PDA
Symptomatic moderate/large PDA surgery recommendations
- Closure for symptoms of left to right shunting, left sided volume overload, reversible pulmonary arteries hypertension
- Children < 5 kg/11 lbs: surgical ligation
- > 5 kg/11 lbs: percutaneous occlusion, surgical ligation for large PDA
What are 3 possible scenarios arising from pulmonary stenosis
- Stenosis of valve itself: 3 leaflets either thickened or fused
- Thickened muscle below valve makes tight
- Stenosis of pulmonary artery below valve
What does pulmonary stenosis lead to?
- Right-sided heart failure
- Microangiopathic hemolytic anemia –> schistocytes (d/t going through tight valve)
Pathophysiology of pulmonary stenosis
- Obstruction of blood flow across pulmonary valve
- Increased work by R ventricle –> hypertrophy
- If obstruction severe, R-L shunt (Eisenmenger syndrome) at atrial level through PFO
- If critical pulmonary stenosis in neonates, only way to get blood to lungs is through PDA —> prostaglandin given at time of birth to keep PDA open
Signs and symptoms of pulmonary stenosis
- Asymptomatic with normal health if mild to moderate PS
- Normal pulses
- May show symptoms later in adolescence or adulthood
- Systolic ejection murmur at the LUSB that increases with inspiration
- S2 followed by opening click that becomes louder with expiration
- RV life on palpation of precordium