Echocardiography in the diagnosis of patients with absent pulmonary valve syndrome: a review study of 12 years.

Absent pulmonary valve syndrome (APVS) is a rare congenital heart disease that is easily misdiagnosed as tetralogy of Fallot (TOF). We herein discuss the echocardiographic features of APVS, compare its two subtypes, and clarify some differences between APVS and TOF. From July 1998 to October 2011, 31 patients diagnosed with APVS at Fuwai Hospital underwent echocardiography, computed tomography, or cardiac angiography. APVS was clinically categorized as either infant-type or child-type. We compared the echocardiographic similarities and differences between APVS and TOF and between the two subtypes of APVS. Although enlargement or aneurysmal dilatation was present in the main pulmonary artery (PA) and its branch in most patients, pulmonary dysplasia or even an absent left PA was found in a few patients. Four important echocardiographic features of APVS useful for distinguishing this syndrome from TOF were (1) absence of the pulmonary valve or presence of pulmonary valve dysplasia, (2) concurrent stenosis and regurgitation at the pulmonary annulus, (3) significant aneurysmal dilatation in the areas of the PAs, and (4) increased rather than decreased PA pressure. 10 patients had infant-type APVS and 21 had child-type APVS. Compared with child-type APVS, infant-type APVS was usually characterized by a lower oxygen saturation, more dilated main PA and right PA, lower aorta-PA ratio, higher diastolic PA pressure, and lower incidence of an absent left PA. Echocardiography is important for diagnosing APVS and distinguishing it from TOF. There are minimal differences in the echocardiographic features between infant-type and child-type APVS.