Background: Absence of semilunar valves is a rare congenital anomaly. Absent pulmonary valve leaflets (APVL) is associated with tetralogy of Fallot (ToF), pulmonary insufficiency, pulmonary artery dilation and respiratory failure. APVL can occur with other malformations, and little is known about absent aortic valve leaflets (AAVL).
Objective: Review our experience with prenatal diagnosis and outcome of absent semilunar valves.
Methods/Results: Eighteen cases were identified between 2001-8; two AAVL, 16 APVL. Initial evaluation occurred at 26±6 wks. Of the AAVL, 1 had cystic hygroma with Turner’s syndrome and 1 had VSD with interrupted aortic arch - both died in-utero at 15 and 37 wks, respectively. Of APVL, 10 had ToF and 6 had non-ToF anatomy including 5 with unique right-sided disease: tricuspid/RV hypoplasia, intact ventricular septum and subaortic stenosis due to bulging septum (3); tricuspid atresia, VSD and complete heart block (1); tricuspid atresia, intact ventricular septum (1). One fetus with APVL had two good size ventricles, aorto-pulmonary window and intact ventricular septum. Of the 10 ToF group, 3 terminated pregnancy, and 5 are alive after surgery, 1 with tracheostomy. Of the 6 non-ToF group, 1 died in-utero, 2 died after birth, 2 survived surgical palliation - both with tracheostomy - and 1 received a heart transplant. Of 12 live-born APVL, only 4 are repaired and breathing spontaneously.
Conclusions: Congenital absence of semilunar valves can be diagnosed prenatally. AAVL is rare and lethal. APVL with non-ToF anatomy is commonly associated with right heart hypoplasia and has high morbidity and mortality.