Case presentation
A female infant with a birth weight of 2,231 g was delivered vaginally at a gestational age of 37 weeks and 6 days. A fetal echocardiogram revealed a heart abnormality with severe aortic and pulmonary stenosis. Tracheobronchial tree and lung abnormality were not reported in fetal diagnosis. After birth, she was tachydyspneic and cyanotic with a loud “to-and-fro” murmur over the left sternal border. Hepatomegaly was observed. Chest radiography revealed a cardiothoracic ratio of 80%. Echocardiography showed the absence of pulmonary valve with pulmonary insufficiency and stenosis, L-TGA, dextrocardia, double outlet left ventricle, hypoplastic anatomical right ventricle, valvular aortic stenosis, atrial septal defect, and patent ductus arteriosus with a bidirectional shunt. Computed tomography (CT) showed a severe hypertrophic anatomical left ventricle connected to the left displaced and dilated main pulmonary artery, with dilation of both branches (Figure 1). The compression of the left main bronchus by the dilated pulmonary artery was diagnosed as tracheomalacia (Figure 2A). The left lung was compressed by the enlarged heart and was suspected to be hypoplastic. It had a less vascular shadow than the right lung.
A tracheal tube was placed immediately after birth because the spontaneous breathing effort was severe, and left lung sounds could not be heard on auscultation. A Ventricular arrhythmia requiring adrenalin infusion immediately after birth indicated severe heart failure. Six hours after delivery, the patent ductus arteriosus was ligated because of increased pulmonary insufficiency and exacerbation of heart failure. On postnatal day 5, percutaneous balloon aortic valvuloplasty was performed for critical aortic valve stenosis. This reduced the peak pressure gradient from 25 mmHg to 20 mmHg. At 4 months age, anatomical left ventricle to pulmonary artery shunt using an 8-mm expanded polytetrafluoroethylene bicuspid-valved conduit with bulging sinuses (Stretch Vascular Graft, W.L. Gore & Associates, Inc., Flagstaff, AZ, USA) and pulmonary artery plication were performed. Although pulmonary insufficiency could be controlled completely with the operation, tracheomalacia of the left main bronchus remained (Figure 2B), and a high positive ventilation setting was still required after the operation. Tracheostomy was performed at the age of five months. There was poor postoperative weight gain and repeated necrotizing enterocolitis. Cartelization showed that her Qp:Qs was 1.6:1, and aortopulmonary collaterals were observed from the right intrathoracic artery. Embolization of the aortopulmonary collateral was performed to decrease the pulmonary blood flow at the age of nine months. Conduit was clipped at the age of ten months to decrease pulmonary blood flow. There was good weight gain, and positive ventilation was not required after the surgery, although tracheomalacia of the left main bronchus persisted on CT. Despite recurrent respiratory tract infections, the patient was discharged at the age of 14 months in a stable condition while waiting for the Glenn procedure until getting her parent’s permission.