Pulmonary Stenosis - Atresia
1. Critical Pulmonary Valve Stenosis in Neonates - Morphology
Pulmonary valve
Uniform fibrous cone with stenotic orifice
Shortened, thickened, with rigid leaflet tissue (Pulmonary valvar dysplasia)
Right ventricle
Mild to moderate reduction of cavity size
Tricuspid valve
Normal tricuspid valve dimensions = 50%
Right ventricle to coronary artery fistula
Sinusoids = 10%
RV coronary arterial fistulae = 2%
RV dependent coronary circulation is rare
Right atrium
Large, ASD/PFO
2. Clinical Features
Critically ill, irritable, tachypneic, severely hypoxic
CXR - normal or enlarged cardiac silhouette, clear lung fields
ECHO is diagnostic
EKG - diminished RV potentials due to small cavity size
3. Natural History
Presentation within two weeks after birth
Neonates with severe hypoxia die without treatment
Early death in treated neonates = 6%
4. Operative Intervention
Percutaneous catheter balloon valvotomy
Open pulmonary valvotomy with/or without cardiopulmonary bypass
Transannular patch
Aorto-pulmonary artery shunt
Balloon Valvotomy
Open Pulmonary Volvotomy
Transannular Patch
Aorto-Pulmonary Shunt
PULMONARY STENOSIS - INFANTS, CHILDREN, & ADULTS
5. Morphology
Pulmonary valve
Fairly well formed with partial commissural fusion
Pulmonary artery
70% have post stenotic dilatation
Right ventricle
Important hypoplasia uncommon
Tricuspid valve
Usually morphologically normal
Right atrium
75% have PFO or ASD
6. Clinical Features
10% of congenital heart disease
Female greater than male
Symptoms
Infants have less symptoms than neonates
Older than 1 year--murmur only
Second, third, and fourth decade of life chronic right heart failure
30-40% with severe pulmonary stenosis are asymptomatic when first examined
Dyspnea of exertion is most common
7. Signs
Harsh systolic murmur
Ejection click
Right ventricular heave
Electrocardiogram
Prominent P waves
Right axis deviation
ECHO
Diagnostic
8. Natural History
Patients presenting in infancy
Infundibular narrowing adds to RVOTO
Severe RVOTO
Congestive heart failure and cyanosis is common
Prognosis poor
Moderate RVOTO
Congestive heart failure present in some
9. Patients presenting after infancy
Mild right ventricular obstruction
Normal probability of survival
RV to PA gradient = 25 mmHg
Peak RV pressure = 50 mmHg
Moderately severe right ventricular obstruction
Excellent survival to 25 years
RV to PA gradient = 25-50 mmHg
RV pressure = 50-80 mmHg
Severe RV obstruction
Susceptible to CHF and primature death
10. Treatment Plan and Results
Balloon valvuloplasty
Results
Mortality should approach zero
PULMONARY ATRESIA & INTACT VENTRICULAR SEPTUM
11. Definition
Congenital malformation in which the pulmonary valve is atretic, ventricular septum is intact, with a variable degree of right ventricular and tricuspid valve hypoplasia
12. Morphology
Pulmonary valve
Commissural ridges suggest a remnant of pulmonary valve
Pulmonary Arteries
Usually near normal size
Right Ventricle
Cavity size is variable
Cavity enlarged = 5%
Cavity severely reduced = 60%
13. Right Ventricle to coronary artery fistula
Inversely related to tricuspid valve dimensions and incompetence
Directly related to ventricular pressure
Right ventricular dependent coronary circulation = 10%
Tricuspid Valve
Leaflets thickened and chordae abnormal
Dimensions correlate to the size of right ventricular cavity size
Right atrium
Enlarged, with an ASD or PFO
14. Clinical Features
1-1.5% of congenital heart disease
Symptoms and Signs
Cyanosis is present, progressive as ductus closes
Chest x-ray--clear lung fields, flat pulmonary artery segment
ECHO-- diagnostic
CATH-- look for right ventricular/coronary artery fistulae
Image- Catheterization
Image- Catheterization
15. Treatment Strategy
Size of tricuspid valve or right ventricular cavity size
TV Z-score < -4
Systemic to pulmonary shunt alone
Fontan (single ventricle)
TV Z-score -1 to -4
Systemic - pulmonary shunt and RVOT procedure (transannular patch or valvotomy)
Test occlude shunt in 6-12 months
Z = [observed dimension - mean normal dimension]
Standard deviation around mean normal dimension
16. Results
Hospital deaths = 20%
Risk Factors
Dimensions of the tricuspid valve
Right ventricular dependent coronary circulation
Aorto-pulmonary artery shunt
Birth weight
17. Operation, Second Stage
Approach depends on growth of right ventricle and tricuspid valve
Normal or moderately reduced RV size
RV outflow tract reconstruction
Maintains two ventricles
Severely reduced RV size
Fontan procedure
