Pulmonary Stenosis Flashcards
Definition?
Narrowing of the pulmonary valve, obstructing flow between the right ventricle and pulmonary arteries.
RF?
• Noonan syndrome • LEOPARD syndrome • Williams syndrome • Alagille syndrome Congenital rubella syndrome
ddx ?
• Innocent murmur-asymptomatic, soft and short murmur
• Straight back syndrome-no click but RV systolic murmur on left sternal edge
• Pulmonary artery dilation
• Pulmonary artery stenosis-mid to late systolic murmur radiating to back and lateral lung fields no click
• Aortic valve stenosis-systolic ejection murmur in upper right sternal border, radiating into carotids and left ventricular apex.
• ASD-On auscultation, systolic RV outflow track murmur of functional PS, wide and fixed splitting of S2, no ejection click.
• VSD-On auscultation, pansystolic regurgitant murmur typically at lower sternal border
• Ebstein’s anomaly-Active pre-cordium; on auscultation, softer systolic murmur at lower left sternal border, sometimes ‘quadruple’ rhythm.
• Tetrology of Fallot-more cyanosis, no click
Pulmonary valve atresia-no murmur
aetiology?
Congenital disorders-see risk factors
CP?
• Parasternal crescendo-decrescendo ejection systolic murmur • Radiates to back • Early systolic pulmonary ejection click or wide S2 split • Rheumatic fever • Signs of congenital disorders • Chest pain • Fatigue • Syncope Signs of RHF-heave and thrills
pathophysiology?
• Systole-opens to allow flow from RV into pulmonary artery and in diastole it is closed to allow filling of ventricles
• In systole it doesn’t open fully so as the pressure increases with blood flow, the pitch changes as the turbulence does
• In S2- it takes a high pressure to close the vlave-hence the split
• In congenital conditions it is malformed so is unable to open fully
• Thickening of leaflets in previous MI
• Leaflets not separated before birth
• Rheumatic fever causes fibrosis
The increased pressure needed to force blood through in systole causes right V hypertrophy and increased metabolic demands on it, predisposing it to RHF
Investigations ?
• ECG-
• Right axis deviation, large R wave, tall P wave in II and V1 to V3
• CXR-
• Pulmonary artery shadow, cardiomegaly, R heart enlargement, low pulmonary vascularity
• Echo with Doppler-morphology, increased transvalvular gradient across valve
• Hb and Hct-increased if cyanosis
• Pulse oximetry-low sats if cyanosed
ABG-low in central cyanosis
Management mild?
observation
management moderate first line?
• Percutaneous balloon pulmonary valvuloplasty
• Considered if Doppler pressure gradient above 60, RV hypertrophy and clinical symptoms
Less invasive and decreases neonatal mortality
management moderate second line?
• Surgical valvuloplasty
• Cuts valve to relieve obstruction if no balloon dilation, many fixed obstructions or re-obstructions
Endocarditis prophylaxis prior to high-risk procedures
management severe first line?
- Percutaneous balloon pulmonary valvuloplasty
- Considered if Doppler pressure gradient above 60, RV hypertrophy and clinical symptoms
- Less invasive and decreases neonatal mortality
management severe second line?
- Surgical valvuloplasty
- Cuts valve to relieve obstruction if no balloon dilation, many fixed obstructions or re-obstructions
- Endocarditis prophylaxis prior to high-risk procedures
management severe cyanosis first line?
- Oxygen and alprostadil (PGE1)
- Dilates arterioles and allows patency of ductus arteriosus increasing blood flow and perfusion to the lungs-
- Percutaneous balloon pulmonary valvuloplasty
- Considered if Doppler pressure gradient above 60, RV hypertrophy and clinical symptoms
- Less invasive and decreases neonatal mortality
- Endocarditis prophylaxis prior to high-risk procedures
management severe cyanosis second line?
- Surgical valvuloplasty
- Cuts valve to relieve obstruction if no balloon dilation, many fixed obstructions or re-obstructions
- Endocarditis prophylaxis prior to high-risk procedures
Prognosis?
- If mild, normal survival
- Percutaneous has good prognosis
- Surgery has less re-interventions but more complications
- Risk factors include pressure age of intervention
