Atypical Shone's complex diagnosed by echocardiography.

Shone's complex is a rare and severe type of congenital left-sided obstructive lesion of multiple cardiovascular levels. This report aims to present the authors' experience diagnosing atypical Shone's complex using echocardiography. Atypical Shone's complex was diagnosed for 38 consecutive patients (18 boys and 20 girls, ages 1 day to 15 years) using echocardiography. All the diagnoses were confirmed by cardioangiography, surgery, or both. Among the congenital left-sided obstructive lesions, four levels of obstruction coexisted in 3 cases (7.9%), three levels in 10 cases (26.3%), and two levels in 25 cases (65.8%). Supra-annular mitral stenosis caused by a supravalvular mitral ring was diagnosed in 1 case. Mitral valvular stenosis was diagnosed in 24 cases including a parachute mitral valve (4 cases), a double-orifice mitral valve (1 case), and partly fused thickened mitral valvular leaflets (19 cases). Subaortic stenosis was diagnosed in 10 cases including circumferential membranous subaortic stenosis (1 case), tunnel-type subaortic narrowing (2 cases), and asymmetric obstructive fibrous ridge below the aortic valve (7 cases). Aortic stenosis was diagnosed in 25 cases including the bicuspid aortic valve (12 cases), the hypoplasia aortic annulus (3 cases), and partly fused or thickened tri-leaflet aortic valves (10 cases). Supra-aortic stenosis was diagnosed in 6 cases including the localized type (4 cases) and the diffused type (2 cases). Coarctation of the aorta was diagnosed in 26 cases. Of these, focal coarctation was described in 15 cases, long segment coarctation in 7 cases, and dysplastic isthmus and/or descending aorta in 4 cases. Secondary changes in Shone's complex manifested as left atrial dilation (26 cases), left ventricular hypertrophy (26 cases), and pulmonary hypertension (19 cases). Echocardiography plays an important role in the diagnosis of atypical Shone's complex, in comprehensive evaluation of the number, position, morphology, and severity of left-sided obstructions.