Introduction: Dysplastic pulmonary valve, sometimes loosely termed ' Absent Pulmonary Valve Syndrome' (APVS), is a rare abnormality which is usually not diagnosed antenatally.
Case Report: Patient was a 24 year old Malay woman, G1P0. She had cystectomy of an endometriotic cyst in 2004. She conceived spontaneously in 2007. She was seen in our department at 7 weeks amenorrhoea. Nuchal translucency measured 1.1 mm at 12.4 weeks. She had a fetal anomaly screening scan at 22.6 weeks amenorrhoea. The abnormalities seen included (i) Dilatation of the pulmonary artery which measured 6.5 mm, (ii) Aorta measured 4.6 mm . Colour Doppler detected turbulent flow, suggestive of pulmonary regurgitation, in the main pulmonary artery with peak velocity of 80.5 cm/s. The pulmonary valves appeared tethered. Impression was that the pulmonary valves were dysplastic. A repeat scan was performed for her a week later and no abnormality was noted.
She went into spontaneous labour at 40 weeks amenorrhoea . A female baby was delivered, weight 3500gms. A cardiac murmur was detected and the baby underwent a 2-dimensional echocardiography on day 3 of life. The pulmonary valves were found to be thickened and tethered, and domed during systole. Findings were in keeping with dysplastic pulmonary valves. In addition there were a small PDA and ASD.
Conclusion: The ultrasound evaluation of dysplastic pulmonary valves in the mid-second trimester may be difficult, probably due to the incomplete expression of the disease at this stage.